list of phenyltropanes

{{Short description|none}}

{{cleanup|reason=unencyclopediac details in tables: compound-numbers specific to certain references ("7e", for example)|date=May 2019}}

Phenyltropanes (PTs) are a family of chemical compounds originally derived from structural modification of cocaine. The main feature differentiating phenyltropanes from cocaine is that they lack the ester functionality at the 3-position terminating in the benzene; thus, the phenyl is attached direct to the tropane skeleton (hence the name "phenyl"-tropane) with no further spacer that the cocaine benzoyloxy provided. The original purpose of phenyltropane-related research was to extirpate the cardiotoxicity inherent in the local anesthetic "numbing" capability of cocaine (which stems from the methylated benzoate ester being essential to cocaine's blockage of sodium channels, and which causes topical anesthesia) while retaining stimulant function.{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#5 Page #929 (5th page of article)] § II}}

Phenyltropane compounds present promising avenues of research into therapeutic applications, particularly in regard to addiction treatment. These compounds' uses vary depending on their construction and structure-activity relationship ranging from the treating of cocaine dependency to understanding the dopamine reward system in the human brain to treating Alzheimer's and Parkinson's diseases. (Since 2008 there have been continual additions to the list and enumerations of the plethora of types of chemicals that fall into the category of this substance profile.[http://v3.espacenet.com/publicationDetails/originalDocument?CC=US&NR=2008153870A1&KC=A1&FT=D&date=20080626&DB=EPODOC&locale=en_gb U.S. Patent Application Publication # US 2008/0153870 A1] M. J. Kuhar, et al. Jun. 26, 2008. Research Triangle Institute.) Certain phenyltropanes can even be used as a smoking cessation aid (cf. RTI-29). Many of the compounds were first elucidated in published material by the Research Triangle Institute and are thus named with "RTI" serial-numbers (in this case the long form is either RTI-COC-n, for 'cocaine' "analog", or specifically RTI-4229-n of the subsequent numbers given below in this article){{efn|Many of the RTI phenyltropanes are "RTI-4229-×××" where × is the specific phenyltropane code number.

e.g. RTI-55 is in-fact RTI-4229-55 but given below as simply RTI-55 for the sake of simplicity in shorthand (following as is done in the literature itself) as the subject matter in context is wholly within the scope of the phenyltropane coded category herein. Sometimes (more rarely) it is given as RTI-COC-××× for "cocaine derivative."

Worth mentioning in notation as to explain that other compounds entirely unrelated can be found with the same "RTI-×××" short-numbered assignation. Therefore it is to be expected that within different contexts a compound or chemical of the same name very possibly could be in reference to an entirely other substance of another chemical series non-analogous to those in this topic.}} Similarly, a number of others are named for Sterling-Winthrop pharmaceuticals ("WIN" serial-numbers) and Wake Forest University ("WF" serial-numbers). The following includes many of the phenyltropane class of drugs that have been made and studied.

File:Phenyltropane.gif|3D rendering of troparil; which comprises a privileged scaffold of among the phenyltropane class of compounds.

File:Troparil structure.png|Troparil structure: cf. {{US patent|5,496,953}}

2-Carboxymethyl esters (phenyl-methyl[[ecgonine]]s)

File:Epibati-tropane.svg|Epibatropane{{US patent|6479509}} containing a nitrogen heteroatom in the benzene ring formation.

File:Tamagnan.png|Tamagnan:{{cite journal | doi = 10.1016/j.bmcl.2004.12.014 | title=Synthesis and monoamine transporter affinity of new 2β-carbomethoxy-3β-[4-(substituted thiophenyl)]phenyltropanes: discovery of a selective SERT antagonist with picomolar potency | journal=Bioorganic & Medicinal Chemistry| date=2005 | volume=15 | issue=4 | pages=1131–1133 | first=Gilles | last=Tamagnan | pmid=15686927}} SSRI, SERT = 17(pM) = 10 times the strength of paroxetine for 5HT.

File:RTI-298.svg|RTI-298

File:RTI-11W.svg|(4′-)para-cis-propenyl-phenyl-methylecgonine. A rare SDRI compound with negligible NET affinity (>2,800.0nM displacement value for NET ligand) that retains significant DAT & SERT (15.0nM & 7.1nM) affinity.

File:Carroll 15.svg|C2-C3 unsaturated (non-isomeric, neither α nor β orientated) 2-naphthyl-tropane

File:Carroll 13.svg|1-naphthyl-tropane in its usual (comparably non-standard) boat formation of its tropane ring.

Like cocaine, phenyltropanes are considered a 'typical' or 'classical' (i.e. "cocaine-like") DAT re-uptake pump ligands in that they stabilize an "open-to-out" conformation on the dopamine transporter; despite the extreme similarity to phenyltropanes, benztropine and others are in suchwise not considered "cocaine-like" and are instead considered atypical inhibitors insofar as they stabilize what is considered a more inward-facing (closed-to-out) conformational state.{{cite journal | date = Jul 2013 | title = Nonclassical Pharmacology of the Dopamine Transporter: Atypical Inhibitors, Allosteric Modulators, and Partial Substrates| journal = J Pharmacol Exp Ther | volume = 346 | issue = 1| pages = 2–10 Fig. 1 | doi = 10.1124/jpet.111.191056 | pmc=3684841 | pmid=23568856 | last1 = Schmitt| first1 = K. C.| last2 = Rothman| first2 = R. B.| last3 = Reith| first3 = M. E.}}

Considering the differences between PTs and cocaine: the difference in the length of the benzoyloxy and the phenyl linkage contrasted between cocaine and phenyltropanes makes for a shorter distance between the centroid of the aromatic benzene and the bridge nitrogen of the tropane in the latter PTs. This distance being on a scale of 5.6 Å for phenyltropanes and 7.7 Å for cocaine or analogs with the benzoyloxy intact.{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#46 Page #970 (46th page of article)] §B, 10th line}} The manner in which this sets phenyltropanes into the binding pocket at MAT is postulated as one possible explanation to account for PTs increased behavioral stimulation profile over cocaine.{{efn|{{Cite journal|url=https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf|doi=10.1002/chin.200020238|title=Chem Inform Abstract: Chemistry, Design, and Structure-Activity Relationship of Cocaine Antagonists|journal=ChemInform|volume=31|issue=20|pages=no|year=2000|last1=Singh|first1=Satendra}} [https://www.scribd.com/doc/77191354/Satendra-Singh-Chemistry-Design-and-Structure-Activity-Relationship-of-Cocaine-Antagonists Mirror hotlink.] ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#47 Page #971 (47th page of article)] 1st ¶, 10th line}}

Blank spacings within tables for omitted data use "no data", "?", "-" or "" interchangeably.

{{sort under}}

class="wikitable sortable sort-under"

|+2β-carbmethoxy-3β-(4′-substituted phenyl)tropanes ({{IC50}} values)
monohalogen halide-phenyltropanes (11a—11e) alkyl-, & alkenyl-phenyltropanes (11r—11x) alkynyl-phenyltropanes (11y & 11z)

! Structure x100px

! Short Name
i.e. Trivial IUPAC
(non-systematic) Name
(Singh's #)

! R (para-substitution)
of benzene

! DA
[3H]WIN 35428
IC50 nM
(Ki nM)

! 5HT
[3H]paroxetine
IC50 nM
(Ki nM)

! NE
[3H]nisoxetine
IC50 nM
(Ki nM)

! selectivity
5-HTT/DAT

! selectivity
NET/DAT

cocaine
(benzoyloxytropane)
H102 ± 12
241 ± 18ɑ
1045 ± 89
112 ± 2b
3298 ± 293
160 ± 15c
10.2
0.5d
32.3
0.7e
x100px(para-hydrogen)phenyltropane
WIN 35,065-2 (β-CPT{{efn|Beta (i.e. 2,3 Rectus)-Carbmethoxy-Phenyl-Tropane}}) Troparil
11a
H23 ± 5.0
49.8 ± 2.2ɑ
1962 ± 61
173 ± 13b
920 ± 73
37.2 ± 5.2c
85.3
3.5d
40.0
0.7e
x100pxpara-fluorophenyltropane
WIN 35,428 (β-CFT{{efn|Beta (i.e. 2,3 Rectus)-Carbmethoxy-Fluorophenyl-Tropane}})
11b
F14 (15.7 ± 1.4)
22.9 ± 0.4ɑ
156 (810 ± 59)
100 ± 13b
85 (835 ± 45)
38.6 ± 9.9c
51.6
4.4d
53.2
1.7e
x100pxpara-nitrophenyltropane
11k
NO210.1 ± 0.10????
x100pxpara-aminophenyltropane
RTI-29{{US patent|6479509}} Method of promoting smoking cessation.
11j
NH29.8
24.8 ± 1.3g
5110151521.415.4
x100pxpara-chlorophenyltropane
RTI-31
11c
Cl1.12 ± 0.06
3.68 ± 0.09ɑ
44.5 ± 1.3
5.00 ± 0.05b
37 ± 2.1
5.86 ± 0.67c
39.7
1.3d
33.0
1.7e
x100pxpara-methylphenyltropane
RTI-32 Tolpane
11f
Me1.71 ± 0.30
7.02 ± 0.30ɑ
240 ± 27
19.38 ± 0.65b
60 ± 0.53e
8.42 ± 1.53c
140
2.8d
35.1
1.2e
x100pxpara-bromophenyltropane
RTI-51 Bromopane
11d
Br1.81 (1.69) ± 0.3010.6 ± 0.2437.4 ± 5.25.820.7
x100pxpara-iodophenyltropane
RTI-55 (β-CIT) Iometopane
11e
I1.26 ± 0.04
1.96 ± 0.09ɑ
4.21 ± 0.3
1.74 ± 0.23b
36 ± 2.7
7.51 ± 0.82c
3.3
0.9d
28.6
3.8e
x100pxpara-hydroxyphenyltropane
11h
OH12.1 ± 0.86
x100pxpara-methoxyphenyltropane
11i
OCH38.14 ± 1.3
x100pxpara-azidophenyltropane
11l
N32.12 ± 0.13
x100pxpara-trifluoromethylphenyltropane
11m
CF313.1 ± 2.2
x100pxpara-acetylaminophenyltropane
11n
NHCOCH364.2 ± 2.6
x100pxpara-propionylaminophenyltropane
11o
NHCOC2H5121 ± 2.7
x100pxpara-ethoxycarbonylaminophenyltropane
11p
NHCO2C3H5316 ± 48
x100pxpara-trimethylstannylphenyltropane
11q
Sn(CH3)3144 ± 37
x100pxpara-ethylphenyltropane
RTI-83
11g
Et55 ± 2.128.4 ± 3.8
(2.58 ± 3.5)
4030 (3910) ± 381
(2360 ± 230)
0.573.3
x100pxpara-n-propylphenyltropane
RTI-282i
11r
n-C3H768.5 ± 7.170.4 ± 4.13920 ± 1301.057.2
x100pxpara-isopropylphenyltropane
11s
CH(CH3)2597 ± 52191 ± 9.575000 ± 58200.3126
x100pxpara-vinylphenyltropane
RTI-359
11t
CH-CH21.24 ± 0.29.5 ± 0.878 ± 4.17.762.9
x100pxpara-methylethenylphenyltropane
RTI-283j
11u
C(=CH2)CH314.4 ± 0.33.13 ± 0.161330 ± 3330.292.4
x100pxpara-trans-propenylphenyltropane
RTI-296i
11v
trans-CH=CHCH35.29 ± 0.5311.4 ± 0.281590 ± 932.1300
x100pxpara-allylphenyltropane
11x
CH2CH=CH232.8 ± 3.128.4 ± 2.42480 ± 2290.975.6
x100pxpara-ethynylphenyltropane
RTI-360
11y
C≡CH1.2 ± 0.14.4 ± 0.483.2 ± 2.83.769.3
x100pxpara-propynylphenyltropane
RTI-281i
11z
C≡CCH32.37 ± 0.215.7 ± 1.5820 ± 466.6346
x100pxpara-cis-propenylphenyltropane
RTI-304
11w
cis-CH=CHCH315 ± 1.27.1 ± 0.712,800k ± 3000.5186.6k
x140pxpara-(Z)-phenylethenylphenyltropanecis-CH=CHPh11.7 ± 1.12
x100pxpara-benzylphenyltropane|
CH2-Ph526 ± 657,240 ± 390
(658 ± 35)
6670 ± 377
(606 ± 277)
13.712.6
x100pxpara-phenylethenylphenyltropaneCH2

-C-Ph
474 ± 1332,710 ± 800
(246 ± 73)
7,060 ± 1,760
(4,260 ± 1,060)
5.714.8
x100pxpara-phenylethylphenyltropanel|
(CH2)2-Ph5.14 ± 0.63234 ± 26
(21.3 ± 2.4)
10.8 ± 0.3
(6.50 ± 0.20)
45.52.1
x100pxpara-(E)-phenylethenylphenyltropanel
RTI-436
trans–CH=CHPh3.09 ± 0.75335 ± 150
(30.5 ± 13.6)
1960 ± 383
(1180 ± 231)
108.4634.3
x120pxpara-phenylpropylphenyltropanel|
(CH2)3-Ph351 ± 521,243 ± 381
(113 ± 35)
14,200 ± 1,800
(8,500 ± 1,100)
3.540.4
x120pxpara-phenylpropenylphenyltropanel|
CH=CH-CH2-Ph15.8 ± 1.31781 ± 258
(71 ± 24)
1,250 ± 100
(759 ± 60)
49.479.1
x100pxpara-phenylbutylphenyltropanel|
(CH2)4-Ph228 ± 214,824 ± 170
(439 ± 16)
2,310 ± 293
(1,390 ± 177)
21.110.1
x100pxpara-phenylethynylphenyltropanel
RTI-298{{Cite journal

| pmid = 12190324

| year = 2002

| last1 = Blough | first1 = B. E.

| last2 = Keverline

| last3 = Nie

| last4 = Navarro

| last5 = Kuhar

| last6 = Carroll

| title = Synthesis and transporter binding properties of 3β-4′-(phenylalkyl, -phenylalkenyl, and -phenylalkynyl)phenyltropane-2β-carboxylic acid methyl esters: evidence of a remote phenyl binding domain on the dopamine transporter

| volume = 45

| issue = 18

| pages = 4029–4037

| journal = Journal of Medicinal Chemistry

| doi = 10.1021/jm020098n | first2 = K. I. | first3 = Z. | first4 = H. | first5 = M. J. | first6 = F. I.

}}

–≡–Ph3.7 ± 0.1646.8 ± 5.8
(4.3 ± 0.53)
347 ± 25
(209 ± 15)
12.693.7
x100pxpara-phenylpropynylphenyltropanel{{Cite journal|doi=10.1021/jm020098n|pmid=12190324|title=Synthesis and Transporter Binding Properties of 3β-[4'-(Phenylalkyl, -phenylalkenyl, and -phenylalkynl)phenyl]tropane-2β-carboxylic Acid Methyl Esters: Evidence of a Remote Phenyl Binding Domain on the Dopamine Transporter|journal=Journal of Medicinal Chemistry|volume=45|issue=18|pages=4029–37|year=2002|last1=Blough|first1=Bruce E.|last2=Keverline|first2=Kathryn I.|last3=Nie|first3=Zhe|last4=Navarro|first4=Hernán|last5=Kuhar|first5=Michael J.|last6=Carroll|first6=F. Ivy}}–C≡C-CH2Ph1.82 ± 0.4213.1 ± 1.7
(1.19 ± 0.42)
27.4 ± 2.6
(16.5 ± 1.6)
7.115
x100pxpara-phenylbutynylphenyltropanel
RTI-430
–C≡C(CH2)2Ph6.28 ± 1.252180 ± 345
(198 ± 31)
1470 ± 109
(885 ± 66)
347.1234
x100pxpara-phenylpentynylphenyltropanel–C≡C-(CH2)3-Ph300 ± 371,340 ± 232
(122 ± 21)
4,450 ± 637
(2,680 ± 384)
4.4614.8
x100pxpara-trimethylsilylethynylphenyltropane
x100pxpara-hydroxypropynylphenyltropane
x100pxpara-hydroxyhexynylphenyltropanel–C≡C-(CH2)4OH57 ± 4828 ± 29
(75 ± 2.6)
9,500 ± 812
(5,720 ± 489)
14.5166.6
x100pxpara-(thiophen-3-yl)phenyltropane
Tamagnan
p-thiophene120.0171890.00141615.7
x100pxpara-biphenyltropane
11aa
Ph10.3 ± 2.6f
29.4 ± 3.8ɑ
15.6 ± 0.6
95.8 ± 36
(8.7 ± 3.3)
1,480 ± 269
(892 ± 162)
6.194.8
x110px3β-2-naphthyltropane
RTI-318
11bb
3β-2-naphthyl0.51 ± 0.03
3.32 ± 0.08f
3.53 ± 0.09ɑ
0.80 ± 0.06
(0.07 ± 0.1)
21.1 ± 1.0
(12.7 ± 0.60)
1.541.3
x100pxpara-bimethoxyphenyltropane
15
OCH2OCH3h

* ɑ[3H]DA uptake displacement Ki value.

  • b[3H]5-HT uptake displacement Ki value.
  • c[3H]NE uptake displacement Ki value.

|

  • d[3H]5-HT uptake to [3H]DA uptake ratio.
  • e[3H]NE uptake to [3H]DA uptake ratio.
  • fIC50 for displacement of [3H]cocaine.
  • gValues from alternate data-set differing from that used in rest of table.
  • hOriginal source (Scheme 4, page 931, 7th of article) name given for compound (bottom of first ¶) is at variance with formula in scheme on same page: i.e. "methoxymethyl" versus "methoxymethoxy"

|

  • iProtonated as the (-)—tartrate salt (isomer)
  • jProtonated as the tartrate salt
  • kWas cited by S. Singh as 28,000nM for SERT or a DAT/SERT ratio of 1,867. However, in Singh's paper he cited J. Med. Chem. 1996, 39, 4030, Table 1{{cite journal | last1 = Blough |display-authors=etal | date = Sep 1996 | title = Synthesis and transporter binding properties of 3β-(4'-alkyl-, 4'-alkenyl-, and 4'-alkynylphenyl)nortropane-2 β-carboxylic acid methyl esters: serotonin transporter selective analogs | journal = J Med Chem | volume = 39 | issue = 20| pages = 4027–35 | pmid = 8831768 | doi=10.1021/jm960409s|s2cid=21616809 }} which shows a ten times lower value, which is consistent with numerous RTI patents published showing the ten-× lower value.
  • lWhereas many bulky additions to the arene unit of phenyltropanes hinder and impair affinity, it has been observed that the para-substituted rigid triple bond analogs terminating in a second phenyl (off of the initial C3 position phenyl) have a high-binding affinity, putatively attesting to the existence of another binding domain that extends beyond the usual ending point where the benzene accords to the acceptor somewhere along the length of range inhabited by the DAT, corresponding to a 180° extension outward from the para area of the aryl of these type of ligands.

=(4′-Monosubstituted 2,3-Thiophene phenyl)-tropanes=

{{sort under}}

class="wikitable sortable sort-under"

|+Tamagnan (thiophene) analogues of para-phenyltropanes.

! Compound structure

! Alphanumeric code
(name)

! para-substitution

! N8

! SERT

! DAT

! NET

! Selectivity
SERT versus DAT

! Selectivity
SERT versus NET

1
(cocaine)
(—)-CocaineCH310508933200.083.2
2
(β-CIT), (Iometopane)
IodoCH30.46 ± 0.060.96 ± 0.152.80 ± 0.402.16.1
(R,S-Citalopram)1.6016,5406,19010,3383,869
x100px4a2-ThiopheneCH30.15 ± 0.01552 ± 12.8158 ± 123461,053
x100px4b
(Tamagnan)
3-ThiopheneCH30.017 ± 0.00412.1 ± 3189 ± 8271011,118
x100px4c2-(5-Br)-ThiopheneCH30.38 ± 0.0086.43 ± 0.9324 ± 1917853
x100px4d2-(5-Cl)-ThiopheneCH30.64 ± 0.044.42 ± 1.64311 ± 256.9486
x100px4e2-(5-I)-ThiopheneCH34.56 ± 0.8422.1 ± 3.21,137 ± 1234.9249
x100px4f2-(5-NH2)-ThiopheneCH364.7 ± 3.7>10,000>30,000>155>464
x100px4g2-(4,5-NO2)-ThiopheneCH35,000>30,000>10,000>6.0>2.0
x100px4h3-(4-Br)-ThiopheneCH34.02 ± 0.34183 ± 69>10,00046>2,488
x100px5a2-ThiopheneH0.11 ± 0.00612.2 ± 0.975.3 ± 9.6111685
x100px5b3-ThiopheneH0.23 ± 0.026.4 ± 0.2739 ± 0.828170

= (3′,4′-Disubstituted phenyl)-tropanes =

File:RTI-318 structure.png

File:RTIthreefivethree.png

File:Phenyltropane 17c.svg

File:RTI-112.svg

class="wikitable"

!Compound
(+ S. Singh's name)!!X
(4′-para)!!Y
(3′-meta)!! 2 Position !! config !! 8 !! DA !! 5-HT !! NE

RTI-318
11bb
colspan=2|β-naphthylCO2Meβ,βNMe0.50.8120
Dichloropane (RTI-111ɑ)
17c
ClClCO2Meβ,βNMe0.793.1318.0
RTI-88 [recheck]
17e
NH2ICO2Meβ,βNMe1.351329c320c
RTI-97
17d
NH2BrCO2Meβ,βNMe3.91181282
RTI-112b
17b
ClMeCO2Meβ,βNMe0.8210.536.2
RTI-96
17a
FMeCO2Meβ,βNMe2.9576520
RTI-295EtICO2Meβ,βNMe21.32.961349
RTI-353 (EINT)EtICO2Meβ,βNH3310.69148
RTI-279MeICO2Meβ,βNH5.981.0674.3
RTI-280MeICO2Meβ,βNMe3.126.81484
Meltzer{{Cite journal | doi = 10.1016/j.bmcl.2003.07.014| pmid = 14592523| title = Synthesis and biological activity of 2-Carbomethoxy-3-catechol-8-azabicyclo[3.2.1]octanes| journal = Bioorganic & Medicinal Chemistry Letters| volume = 13| issue = 22| pages = 4133–4137| year = 2003| last1 = Meltzer | first1 = P. C. | last2 = McPhee | first2 = M. | last3 = Madras | first3 = B. K. }}colspan=2|catecholCO2Meβ,βNMe>100??
MeltzerOAcOAcCO2Meβ,βNMe???

  • ɑas ·HCl (salt)
  • bas ·HCl·2 H2O (salt)
  • cSingh gives the reverse value with respect to i.e. 1,329 for NET & 320 for 5-HT

{{sort under}}

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|+Para-meta-substituted 2β-carbomethoxy-3α-(4′-substituted phenyl)tropanes

! Compound 150px

! Short Name
(S. Singh)

! R2

! R1

! DA

! 5HT

! NE

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

150pxmeta-fluorophenyltropane
16a
FH23 ± 7.8|
150pxmeta-chlorophenyltropane
16b
ClH10.6 ± 1.8|
150pxmeta-bromophenyltropane
16c
BrH7.93 ± 0.08ɑ|
|150pxmeta-iodophenyltropane
16d
IH26.1 ± 1.7|
160pxmeta-tributylstannylphenyltropane
16e
SnBu3H1100 ± 170|
160pxmeta-ethynylphenyltropaneC≡CHH|
150pxmeta-methyl-para-fluorophenyltropane
RTI-96
17a
CH3F2.95 ± 0.58|
150pxmeta-methyl-para-chlorophenyltropane
RTI-112c
17b
CH3Cl0.81 ± 0.0510.5 ± 0.0536.2 ± 1.013.044.7
150pxmeta-para-dichlorophenyltropane
RTI-111b{{cite journal|doi=10.1021/jm00059a010|pmid=8464040|title=Substituted 3-phenyltropane analogs of cocaine: Synthesis, inhibition of binding at cocaine recognition sites, and positron emission tomography imaging|journal=Journal of Medicinal Chemistry|volume=36|issue=7|pages=855–62|year=1993|last1=Meltzer|first1=P. C.|last2=Liang|first2=A. Y.|last3=Brownell|first3=A. L.|last4=Elmaleh|first4=D. R.|last5=Madras|first5=B. K.}} Dichloropane
17c
ClCl0.79 ± 0.08b3.13 ± 0.36b18.0 ± 0.8
17.96 ± 0.85bd
4.0b22.8b
160pxmeta-bromo-para-aminophenyltropane
RTI-97
17d
BrNH23.91 ± 0.5918128246.272.1
160pxmeta-iodo-para-aminophenyltropane
RTI-88
17e
INH21.35 ± 0.11120 ± 41329 ± 12488.9984
160pxmeta-iodo-para-azidophenyltropane
17f
IN34.93 ± 0.32|

{{sort under}}

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|+3β-(4-alkylthio, -methylsulfinyl, and -methylsulfonylphenyl)tropanes{{cite journal|last1=Jin|first1=Chunyang|last2=Navarro|first2=Hernán A.|last3=Ivy Carroll|first3=F.|title=Synthesis and structure–activity relationship of 3β-(4-alkylthio, -methylsulfinyl, and -methylsulfonylphenyl)tropane and 3β-(4-alkylthiophenyl)nortropane derivatives for monoamine transporters|journal=Bioorganic & Medicinal Chemistry|volume=17|issue=14|year=2009|pages=5126–5132|issn=0968-0896|doi=10.1016/j.bmc.2009.05.052|pmid=19523837|pmc=2747657}}

! Structure 150px

! Compound

! R

! X

! n

! Inhibition of [3H]WIN 35,428
@ DAT
IC50 (nM)

! Inhibition of [3H]Paroxetine
@ 5-HTT
Ki (nM)

! Inhibition of [3H]Nisoxetine
@ NET
Ki (nM)

! NET/DAT
(uptake ratio)

! NET/5-HTT
(uptake ratio)

CocaineDes-thio/sulfinyl/sulfonyl
H
HDesmethyl
0
89.19519902221
para-methoxyphenyltropane
Singh: 11i
Des-thio/sulfinyl/sulfonyl
OCH3
H06.5 ± 1.34.3 ± 0.51110 ± 64171258
190px7aCH3H09 ± 30.7 ± 0.2220 ± 1024314
200px7bC2H5H0232 ± 344.5 ± 0.51170 ± 3005260
200px7cCH(CH3)2H016 ± 223 ± 2129 ± 287
200px7dCF3H0200 ± 708 ± 21900 ± 30010238
180px7eCH3Br010.1 ± 10.6 ± 0.2121 ± 1212202
180px7fCH3Br176 ± 183.2 ± 0.4690 ± 809216
180px7gCH3H191 ± 164.3 ± 0.6515 ± 606120
180px7hCH3H2>10,000208 ± 45>10,000148

= (2′,4′-Disubstituted phenyl)-tropanes =

{{sort under}}

class="wikitable sortable sort-under"

|+Ortho-para-substituted (2′,4′-disubstituted phenyltropanes)

! Compound structure
x130px

! Trivial IUPAC
(non-systematic)
Name

! R2
ortho

! R1
para

! DA

! 5HT

! NE

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

185pxortho,para-dinitrophenyltropane{{cite journal|author=R. H. Kline, Davies, E. Saikali, T. Sexton & S.R. Childers|title=Novel 2-substituted cocaine analogs: Binding properties at dopamine transport sites in rat striatum|journal=European Journal of Pharmacology|volume= 244|issue=1|pages= 93–97|year=1993|pmid=8420793|doi=10.1016/0922-4106(93)90063-f}}NO2NO2 |

= (3′,4′,5′-Trisubstituted ''para''-methoxyphenyl)-tropanes =

{{sort under}}

class="wikitable sortable sort-under"

|+Para-meta(3′)-meta(5′)-(di-meta)-substituted 2β-carbomethoxy-(3′,4′,5′-substituted phenyl)tropanes{{Cite journal|pmc=2841478|id=Table 1|year=2008|last1=Jin|first1=C|title=Development of 3-Phenyltropane Analogs with High Affinity for the Dopamine and Serotonin Transporters and Low Affinity for the Norepinephrine Transporter|journal=Journal of Medicinal Chemistry|volume=51|issue=24|pages=8048–8056|last2=Navarro|first2=H. A.|last3=Carroll|first3=F. I.|doi=10.1021/jm801162z|pmid=19053748}}
Para-methoxy/(ethoxy)-meta-substituted phenyltropanes

! Structure
210px

! {{verth|va=middle|Short Name
(All compounds tested
as HCl salts)}}

! {{verth|va=middle|R2
3′-(meta)}}

! {{verth|va=middle|R3
5′-(di-meta)}}

! {{verth|va=middle|OR1
4′-(para)}}

! DAT
IC50
{{chem2|[^{3}H]}}(compound #)12

! 5-HTT
Ki
{{chem2|[^{3}H]}}Paroxetine

! NET
Ki
{{chem2|[^{3}H]}}Nisoxetine

! Selectivity
NET/DAT
Ratio
Ki/IC50

! Selectivity
NET/5-HTT
Ratio
Ki/Ki

Cocaine|
|89.19519902221
6
RTI-112|
|0.82 ± 0.050.95 ± 0.0421.8 ± 0.62723
File:Cocaine analog Carroll 7a.svg7a
11i
HHCH36.5 ± 1.34.3 ± 0.51110 ± 64171258
File:Cocaine analog Carroll 7b.svg7bHHC2H592 ± 81.7 ± 0.41690 ± 5018994
File:Cocaine analog Carroll 7c.svg7cFHCH316 ± 14.8 ± 0.5270 ± 501756
File:Cocaine analog Carroll 7d.svg7dBrHCH347 ± 153.1 ± 0.1160 ± 20352
File:Cocaine analog Carroll 7f.svg7fBrBrCH392 ± 222.9 ± 0.14100 ± 400ɑ451413
File:Cocaine analog Carroll 7e.svg7eIHCH3170 ± 603.5 ± 0.4180 ± 20151
File:Cocaine analog Carroll 7g.svg7gIICH31300 ± 2007.5 ± 0.8180 ± 204667

ɑN=2

= (2′,4′,5′-Trisubstituted phenyl)-tropanes =

{{sort under}}

class="wikitable sortable sort-under"

|+Ortho-para(4′)-meta(5′)-trisubstituted 2β-carbomethoxy-(2′,4′,5′-substituted phenyl)tropanes

! Structure

! Short Name

! {{verth|va=middle|R1
2′-(ortho)}}

! {{verth|va=middle|R2
4′-(para)}}

! {{verth|va=middle|R3
5′-(meta)}}

! {{verth|va=middle|DAT}}

! {{verth|va=middle|5-HTT}}

! {{verth|va=middle|NET}}

! Selectivity
NET/DAT
Ratio

! Selectivity
NET/5-HTT
Ratio

x130pxpara-ethyl-ortho, meta-diiodophenyltropaneiodoethyliodo{{sdash}}{{sdash}}{{sdash}}{{sdash}}{{sdash}}

2-Carbmethoxy modified (replaced/substituted)

= General 2-carbmethoxy modifications =

== 2β-substitutions of ''p''-methoxy-phenyltropanes ==

{{sort-under}}

class="wikitable sortable sort-under"

|+Para-OCH3-(3β-(4-Methoxyphenyl)tropane-2β-carboxylic acid ester analogues{{cite journal|pmc=2841478|id=Table 2|year=2008|last1=Jin|first1=C|title=Development of 3-Phenyltropane Analogs with High Affinity for the Dopamine and Serotonin Transporters and Low Affinity for the Norepinephrine Transporter|journal=Journal of Medicinal Chemistry|volume=51|issue=24|pages=8048–8056|last2=Navarro|first2=H. A.|last3=Carroll|first3=F. I.|doi=10.1021/jm801162z|pmid=19053748}}

! Structure
200px

! {{verth|Short Name
(All compounds tested
as HCl salts)}}

! CO2R (2β-substituted)
(compound 9 is 2β=R)

! DAT
IC50
{{chem2|[^{3}H]}}(compound #)12

! 5-HTT
Ki
{{chem2|[^{3}H]}}Paroxetine

! NET
Ki
{{chem2|[^{3}H]}}Nisoxetine

! Selectivity
NET/DAT
Ratio
Ki/IC50

! Selectivity
NET/5-HTT
Ratio
Ki/Ki

File:Cocaine analog Carroll 7a.svg7a
11i
CH36.5 ± 1.34.3 ± 0.51110 ± 64171258
File:Cocaine analog Carrol 8a.svg8a(CH3)2CH14 ± 3135 ± 352010 ± 20014415
File:Cocaine analog Carrol 8b.svg8bcyclopropane6.0 ± 229 ± 31230 ± 14020542
File:Cocaine analog Carrol 8c.svg8ccyclobutane13 ± 3100 ± 8>300023130
File:Cocaine analog Carrol 8d.svg8dO2N...1,4-xylene...(CH2)242 ± 82.9 ± 0.2330 ± 208114
File:Cocaine analog Carrol 8e.svg8eH2N...1,4-xylene...(CH2)27.0 ± 28.3 ± 0.42200 ± 300ɑ314265
File:Cocaine analog Carrol 8f.svg8fCH3CONH...1,4-xylene...(CH2)26.0 ± 15.5 ± 0.51460 ± 30243265
File:Cocaine analog Carrol 8g.svg8gH2N...2-bromo-1,4-dimethylbenzene...(CH2)23.3 ± 1.44.1 ± 0.61850 ± 90561451
File:Cocaine analog Carrol 8h.svg8hH2N...1,3-dibromo-2,5-dimethylbenzene...(CH2)215 ± 62.0 ± 0.42710 ± 250ɑ1811360
File:Cocaine analog Carrol 8i.svg8iH2N...2-iodo-1,4-dimethylbenzene...(CH2)22.5 ± 0.73.5 ± 12040 ± 300ɑ816583
File:Cocaine analog Carrol 8j.svg8jH2N...1,3-diiodo-2,5-dimethylbenzene...(CH2)2102 ± 151.0 ± 0.12600 ± 200ɑ252600
File:Cocaine analog Carroll 9.svg93-(4-methylphenyl)-1,2-oxazole18 ± 6860 ± 170>30001673

ɑN=2

== 2β-carboxy side-chained (''p''-chloro/iodo/methyl) phenyltropanes ==

class="wikitable sortable"

|+Multi-substituted structures of 2β-ester-3β-phenyltropanes

! Compound
150px

! Short Name
(S. Singh)

! R

! X

! IC50 (nM)
DAT
[3H]WIN 35428

! IC50 (nM)
5-HTT
[3H]paroxetine

! IC50 (nM)
NET
[3H]nisoxetine

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

x100px23aCH(CH3)2H85.1 ± 2.523121 ± 397632047 ± 1491272376
x120px23bC6H5H76.7 ± 3.6106149 ± 725619262 ± 5931384251
x100px24aCH(CH3)2Cl1.4 ± 0.13
6.04 ± 0.31ɑ
1400 ± 7
128 ± 15b
778 ± 21
250 ± 0.9c
1000
21.2d
556
41.4e
x100px24bcyclopropylCl0.96 ± 0.10168 ± 1.8235 ± 8.39175245
x120px24cC6H5Cl1.99 ± 0.05
5.25 ± 0.76ɑ
2340 ± 27
390 ± 34b
2960 ± 220
242 ± 30c
1176
74.3d
1.3
41.6e
x150px24dC6H4-4-ICl32.6 ± 3.91227 ± 176967.6 ± 26.337.629.7
x120px24eC6H4-3-CH3Cl9.37 ± 0.522153 ± 1432744 ± 140230293
x140px24fC6H4-4-CH3Cl27.4 ± 1.51203 ± 421277 ± 11843.946.6
x120px24gC6H4-2-CH3Cl3.91 ± 0.233772 ± 3844783 ± 3879651223
x140px24hC6H4-4-ClCl55 ± 2.316914 ± 10564883 ± 28830788.8
x150px24iC6H4-4-OCH3Cl71 ± 5.619689 ± 18431522 ± 9427721.4
x150px24j(CH2)2C6H4-4-NO2Cl2.71 ± 0.13----
x150px24k(CH)2C6H4-4-NH2Cl2.16 ± 0.25----
x150px24l(CH2)2C6H3-3-I-4-NH2Cl2.51 ± 0.25----
x150px24m(CH2)2C6H3-3-I-4-N3Cl14.5 ± 0.94----
x150px24n(CH2)2C6H4-4-N3Cl6.17 ± 0.57----
x150px24o(CH2)2C6H4-4-NCSCl5.3 ± 0.6----
x170px24p(CH2)2C6H4-4-NHCOCH2BrCl1.73 ± 0.06----
x100px25aCH(CH3)2I0.43 ± 0.05
2.79 ± 0.13ɑ
66.8 ± 6.53
12.5 ± 1.0b
285 ± 7.6
41.2 ± 3.0c
155
4.5d
663
14.8e
x100px25bcyclopropylI0.61 ± 0.0815.5 ± 0.72102 ± 1125.4167
x120px25cC6H5I1.51 ± 0.34
6.85 ± 0.93ɑ
184 ± 22
51.6 ± 6.2b
3791 ± 149
32.7 ± 4.4c
122
7.5d
2510
4.8e
x100px| 26aCH(CH3)2CH36.45 ± 0.85
15.3 ± 2.08ɑ
6090 ± 488
917 ± 54b
1926 ± 38
73.4 ± 11.6c
944
59.9d
299
4.8e
x120px26bCH(C2H5)2CH319.1 ± 14499 ± 5573444 ± 44235180
x100px26ccyclopropylCH317.8 ± 0.76485 ± 212628 ± 25227.2148
x110px26dcyclobutylCH33.74 ± 0.522019 ± 1334738 ± 3225401267
x120px26ecyclopentylCH31.68 ± 0.141066 ± 109644 ± 28634383
x120px26fC6H5CH33.27 ± 0.06
9.13 ± 0.79ɑ
24500 ± 1526
1537 ± 101b
5830 ± 370
277 ± 23c
7492
168d
1783
30.3e
x120px26gC6H4-3-CH3CH38.19 ± 0.905237 ± 4532136 ± 208639261
x140px26hC6H4-4-CH3CH381.2 ± 1615954 ± 6144096 ± 12119650.4
x120px26iC6H4-2-CH3CH323.2 ± 0.9711040 ± 50425695 ± 13944761107
x150px26jC6H4-4-ClCH3117 ± 7.942761 ± 23999519 ± 86436581.3
x150px26kC6H4-4-OCH3CH395.6 ± 8.882316 ± 78523151 ± 28286133.0

  • ɑKi value for displacement of [3H]DA uptake.
  • bKi value for displacement of [3H]5-HT uptake.
  • cKi value for displacement of [3H]NE uptake.
  • d[3H]5-HT uptake to [3H]DA uptake ratio.
  • e[3H]NE uptake to [3H]DA uptake ratio.

= Carboxyaryl =

File:RTI-204 structure.png

File:RTIoneonethree.png

File:RTI-120 structure.png

class="wikitable"

!Compound!!X!!2 Position!!config!!8!! DA !! 5-HT !! NE

RTI-122I |
CO2Phβ,βNMe1.501843,791
RTI-113Cl |
CO2Phβ,βNMe1.982,3362,955
RTI-277NO2 |
CO2Phβ,βNMe5.942,9105,695
RTI-120 [recheck]Me |
CO2Phβ,βNMe3.2624,4715,833
RTI-116Cl |
CO2(p-C6H4I)β,βNMe331,227968
RTI-203ClCO2(m-C6H4Me)β,βNMe9.3721532744
RTI-204Cl |
CO2(o-C6H4Me)β,βNMe3.913,7724,783
RTI-205Me |
CO2(m-C6H4Me)β,βNMe8.195,2372,137
RTI-206Cl|
CO2(p-C6H4Me)β,βNMe27.41,2031,278

== 2-Phenyl-3-Phenyltropanes ==

{{sort under}}

class="wikitable sortable sort-under"

|+2-Phenyl-3-phenyltropane binding affinities and inhibition of DA & 5-HT Uptake

! Compound Structure

! {{verth|Short Name
(S. Singh)}}

! {{verth|Stereochemistry}}

! X
(para)

! DAT
[3H]WIN 35428 IC50 (nM)

! DAT
[3H]Mazindol Ki (nM)

! 5-HTT
[3H]Paroxetine IC50 (nM)

! [3H]DA uptake Ki (nM)

! [3H]5-HT uptake Ki (nM)

! Selectivity
{{nowrap|[3H]5-HT}}/{{nowrap|[3H]DA}}

Cocaine(2β,3β)(H)89 ± 4.82811050 ± 894231550.4
x105px67a2β,3βH12.6 ± 1.814.921000 ± 332028.9110038.1
x155px67b2β,3αH-13.8|
|11.775364.3
x135px67c2α,3αH690 ± 37|
|41300 ± 5300|
x170px682β,3αF |
|6.00|
|4.5812226.6
x100px69a2β,3βCH31.96 ± 0.082.5811000 ± 832.8773.825.7
x170px69b2β,3αCH3 |
|2.87|
|4.1628769.0
x145px69c2α,3αCH3429 ± 59|
|15800 ± 3740|

= Carboxyalkyl =

File:RTI-77 structure.png

File:RTI-121.png

File:RTI-150.png

class="wikitable"

!Code!!X!!2 Position!!config!!8!! DA !! 5-HT !! NE

RTI-77ClCH2C2(3-iodo-p-anilino)β,βNMe2.512247
RTI-121 IPCITI |
CO2Priβ,βNMe0.4366.8285
RTI-153I |
CO2Priβ,βNH1.063.59132
RTI-191I |
CO2Prcycβ,βNMe0.6115.5102
RTI-114Cl |
CO2Priβ,βNMe1.401,404778
RTI-278NO2 |
CO2Priβ,βNMe8.142,1474,095
RTI-190Cl |
CO2Prcycβ,βNMe0.96168235
RTI-193Me |
CO2Prcycβ,βNMe1.681,066644
RTI-117Me |
CO2Priβ,βNMe6.456,0901,926
RTI-150Me |
CO2Bucycβ,βNMe3.742,0204,738
RTI-127Me |
CO2C(H)Et2β,βNMe1945003444
RTI-338ethyl|
CO2C2Phβ,βNMe11047.413366

Use of a cyclopropyl ester appears to enable better MAT retention than does the choice of isopropyl ester.

Use of a cycBu resulted in greater DAT selectivity than did the cycPr homologue.

== 2-Alkyl Esters & Ethers ==

=== Esters (2-Alkyl) ===

class="wikitable sortable"

|+2β-Alkyl Ester Phenyltropanes

! Structure

! Short Name
(S. Singh)

! 2β=R

! Ki (nM)
DAT
[3H]WIN 35428

! IC50 (nM)
[3H]DA uptake

! Selectivity
uptake/binding

x110px59aCH=CHCO2CH322 ± 2123 ± 655.6
x110px59bCH2CH2CO2CH323 ± 2166 ± 687.2
x120px59c(CH2)2CH=CHCO2CH320 ± 2203 ± 7710.1
x120px59d(CH22)4CO2CH330 ± 2130 ± 74.3
x90px59eCH=CHCH2OH26 ± 3159 ± 436.1
x90px59fCH2CH2CH2OH11 ± 164 ± 325.8
x110px59gCH2CH2COC6H528 ± 247 ± 151.7

=== Ethers (2-Alkyl) ===

{{See also|{{PAGENAME}}#Paroxetine homologues|l1=N-desmethyl Paroxetine homologues|selfref=y}}

{{sort under}}

class="wikitable sortable sort-under"

|+2-Alkyl Ether Phenyltropanes

! Molecular Structure

! Short Name
(S. Singh)

! {{verth|Stereochemistry}}

! DAT
[3H]WIN 35428 IC50 (nM)

! 5-HTT
[3H]Paroxetine IC50 (nM)

! NET
[3H]Nisoxetine IC50 (nM)

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

Paroxetine623 ± 250.28 ± 0.02535 ± 150.00040.8
x130pxR-60a2β,3β308 ± 20294 ± 185300 ± 4500.917.2
x115pxR-60b2α,3β172 ± 8.852.9 ± 3.626600 ± 12000.3155
x195pxR-60c2β,3α3.01 ± 0.242.2 ± 16123 ± 9.514.140.9
x130pxS-60d2β,3β1050 ± 4588.1 ± 2.827600 ± 11000.0826.3
x115pxS-60e2α,3β1500 ± 74447 ± 472916 ± 19500.31.9
x195pxS-60f2β,3α298 ± 17178 ± 1312400 ± 7200.641.6

= Carboxamides =

{{US Patent|5736123}}

File:RTI-183 structure.png

File:RTI-229 structure.png

File:RTI-227 structure.png

{{sort-under}}

class="wikitable sortable sort-under"

!Structure
x100px!!{{verth|va=middle|Code
(S. Singh #)}}!!X!!2 Position!!{{verth|va=middle|config}}!!8!!DA
[3H]WIN 35428
(IC50 nM)
!!NE
[3H]nisoxetine!!5-HT
[3H]paroxetine
(IC50 nM)
!!Selectivity
5-HTT/DAT!!Selectivity
NET/DAT

x100pxRTI-106
27b
ClCON(H)Meβ,βNMe12.4 ± 1.171584 ± 621313 ± 46106128
x100pxRTI-118
27a
ClCONH2β,βNMe11.5 ± 1.64270 ± 3591621 ± 110141371
x100pxRTI-222
29d
Memorpholinylβ,βNMe11.7 ± 0.8723601 ± 1156>100K>85472017
x100pxRTI-129
27e
ClCONMe2β,βNMe1.38 ± 0.1942 ± 481079 ± 102792683
x100pxRTI-146
27d
ClCONHCH2OHβ,βNMe2.05 ± 0.23144 ± 397.8 ± 1047.770.2
x100pxRTI-147
27i
ClCON(CH2)4β,βNMe1.38 ± 0.033,950 ± 7212400 ± 120789852862
x100pxRTI-156ClCON(CH2)5β,βNMe6.6158323468
x100pxRTI-170ClCON(H)CH2C≡CHβ,βNMe16.518394827
x100pxRTI-172ClCON(H)NH2β,βNMe44.139143815
x130pxRTI-174ClCONHCOMeβ,βNMe158>43K>125K
x160pxRTI-182ClCONHCH2COPhβ,βNMe7.791722827
x110pxRTI-183
27 g
ClCON(OMe)Meβ,βNMe0.85 ± 0.06549 ± 18.5724 ± 94852646
x110pxRTI-186
29c
MeCON(OMe)Meβ,βNMe2.55 ± 0.43422 ± 263402 ± 3531334165
x100pxRTI-198
27h
ClCON(CH2)3β,βNMe6.57 ± 0.67990 ± 4.8814 ± 57124151
x100pxRTI-196
27c
ClCONHOMeβ,βNMe10.7 ± 1.259907 ± 63243700 ± 19604084926
x160pxRTI-201ClCONHNHCOPhβ,βNMe91.8>20K>48K
x110pxRTI-208
27j
ClCONO(CH2)3β,βNMe1.47 ± 0.131083 ± 762470 ± 561680737
x110pxRTI-214
27l
ClCON(-CH2CH2-)2Oβ,βNMe2.90 ± 0.38545 ± 20688769 ± 1855306102946
x110pxRTI-215
27f
ClCONEt2β,βNMe5.48 ± 0.195532 ± 2999433 ± 77017211009
x150pxRTI-217ClCONH(m-C6H4OH)β,βNMe4.78>30K>16K
x100pxRTI-218ClCON(Me)OMeβ,βNMe1.195201911
x150pxRTI-226
27 m
ClCONMePhβ,βNMe45.5 ± 32202 ± 49523610 ± 212851948.4
x100pxRTI-227ICONO(CH2)3β,βNMe0.75446230
x100pxRTI-229{{cite journal|doi=10.1002/(SICI)1099-1344(199903)42:3<281::AID-JLCR188>3.0.CO;2-X|title=Synthesis of 3β-(4-[125I]iodophenyl)tropane-2-β-pyrrolidine carboxamide ([125I]RTI-229)|journal=Journal of Labelled Compounds and Radiopharmaceuticals|volume=42|issue=3|pages=281–286|year=1999|last1=Zhong|first1=Desong|last2=Kotian|first2=Pravin|last3=Wyrick|first3=Christopher D.|last4=Seltzman|first4=Herbert H.|last5=Kepler|first5=John A.|last6=Kuhar|first6=Michael J.|last7=Boja|first7=John W.|last8=Carroll|first8=F. Ivy}}
28a
ICON(CH2)4β,βNMe0.37 ± 0.04991 ± 211728 ± 3946702678
x100px27k6.95 ± 1.211752 ± 2023470 ± 226499252
x100px28b1.08 ± 0.15103 ± 6.273.9 ± 8.168.495.4
x110px28c0.75 ± 0.02357 ± 42130 ± 15.8173476
x100px29a41.8 ± 2.454398 ± 2716371 ± 374152105
x110px29b24.7 ± 1.936222 ± 72933928 ± 21921374252

✲RTI-183 and RTI-218 suggest possible copy-error, seeing as "CON(OMe)Me" & "CON(Me)OMe" difference between methyl & methoxy render as the same.

class="wikitable sortable sort-under"

|+2β-Carboxamide-3β-Phenyltropanes

! Compound

! Short Name
(S. Singh)

! R

! X

! IC50 (nM)
DAT
[3H]WIN 35428

! IC50 (nM)
5-HTT
[3H]Paroxetine

! IC50 (nM)
NET
[3H]Nisoxetine

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

rowspan=5|x100px
29aNH2CH341.8 ± 2.456371 ± 3744398 ± 271152105
29bN(CH2CH3)2CH324.7 ± 1.9333928 ± 21926222 ± 7291374252
29c
RTI-186
N(OCH3)CH3CH32.55 ± 0.433402 ± 353422 ± 261334165
29d
RTI-222
4-morpholineCH311.7 ± 0.87>10000023601 ± 1156>85472017

==Carboxamide linked phenyltropanes dimers==

File:Phenyltropane para chloro dimer.svg

File:Phenyltropane para methyl dimer.svg

File:PhenyltropaneDimerC2Benzenelink.svg

File:PhenyltropaneDimerC2amide.svg

File:PhenyltropaneDimer.svg

Dimers of phenyltropanes, connected in their dual form using the C2 locant as altered toward a carboxamide structural configuring (in contrast and away from the usual inherent ecgonine carbmethoxy), as per Frank Ivy Carroll's patent inclusive of such chemical compounds, possibly so patented due to being actively delayed pro-drugs in vivo.

= Heterocycles =

These heterocycles are sometimes referred to as the "bioisosteric equivalent" of the simpler esters from which they are derived. A potential disadvantage of leaving the ββ-ester unreacted is that in addition to being hydrolyzable, it can also epimerize{{Cite journal

| pmid = 8411004

| year = 1993

| last1 = Carroll | first1 = F. I.

| last2 = Gray

| last3 = Abraham

| last4 = Kuzemko

| last5 = Lewin

| last6 = Boja

| last7 = Kuhar

| title = 3-Aryl-2-(3′-substituted-1′,2′,4'-oxadiazol-5′-yl)tropane analogues of cocaine: affinities at the cocaine binding site at the dopamine, serotonin, and norepinephrine transporters

| volume = 36

| issue = 20

| pages = 2886–2890

| journal = Journal of Medicinal Chemistry

| doi = 10.1021/jm00072a007

}} to the energetically more favorable trans configuration. This can happen to cocaine also.

File:HeterocyclicMEPCmpndModel34.png

Several of the oxadiazoles contain the same number and types of heteroatoms, while their respective binding potencies display 8×-15× difference. A finding that would not be accounted for by their affinity originating from hydrogen bonding.

To explore the possibility of electrostatic interactions, the use of molecular electrostatic potentials (MEP) were employed with model compound 34 (replacing the phenyltropane moiety with a methyl group). Focusing on the vicinity of the atoms @ positions A—C, the minima of electrostatic potential near atom position A (ΔVmin(A)), calculated with semi-empirical (AM1) quantum mechanics computations (superimposing the heterocyclic and phenyl rings to ascertain the least in the way of steric and conformational discrepancies) found a correlation between affinity @ DAT and ΔVmin(A): wherein the values for the latter for 32c = 0, 32g = -4, 32h = -50 & 32i = -63 kcal/mol.

In contrast to this trend, it is understood that an increasingly negative ΔVmin is correlated with an increase of strength in hydrogen bonding, which is the opposing trend for the above; this indicates that the 2β-substituents (at least for the heterocyclic class) are dominated by electrostatic factors for binding in-the-stead of the presumptive hydrogen bonding model for this substituent of the cocaine-like binding ligand.{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#16 Page #940 (16th page of article)] underneath Table 8., above § 4}}

== 3-Substituted-isoxazol-5-yl ==

File:3-R-isoxazol-5-yl.svg

class="wikitable sortable"

|+N-methylphenyltropanes with 1R β,β stereochemistry.

! Code
(S.S. #)

! X

! R

! DA

! NE

! 5HT

RTI-165Cl3-methylisoxazol-5-yl0.59181572
RTI-171Me3-methylisoxazol-5-yl0.932543818
RTI-180I3-methylisoxazol-5-yl0.7367.936.4
RTI-177 β-CPPIT
32g
Cl3-phenylisoxazol-5-yl1.28 ± 0.18504 ± 292420 ± 136
RTI-176Me3-phenylisoxazol-5-yl1.583985110
RTI-181I3-phenylisoxazol-5-yl2.57868100
RTI-184Hmethyl43.36208
RTI-185HPh285>12K
RTI-334Cl3-ethylisoxazol-5-yl0.501203086
RTI-335Clisopropyl1.199542318
RTI-336Cl3-(4-methylphenyl)isoxazol-5-yl4.0917145741
RTI-337Cl3-t-butyl-isoxazol-5-yl7.31632137K
RTI-345Clp-chlorophenyl6.425290>76K
RTI-346Clp-anisyl1.577625880
RTI-347Clp-fluorophenyl1.869187257
RTI-354Me3-ethylisoxazol-5-yl1.622996400
RTI-366MeR = isopropyl4.52523 (1550)42,900 (3900)
RTI-371Mep-chlorophenyl8.74>100K (60,200)>100K (9090)
RTI-386Mep-anisyl3.93756 (450)4027 (380)
RTI-387Mep-fluorophenyl6.45917 (546)>100K (9400)

== 3-Substituted-1,2,4-oxadiazole ==

File:RTI-130 structure.png

File:RTI-126.png

{{sort under}}

class="wikitable sortable sort-under"

|+Heterocyclic (N-methyl)phenyltropanes with 1R stereochemistry.

! Structure

! Code
(Singh's #)

! X

! R

! DAT (IC50 nM)
displacement of {{chem2|[^{3}H]}}WIN 35428

! NET (IC50 nM)
{{chem2|[^{3}H]}}nisoxetine

! 5-HTT (IC50 nM)
{{chem2|[^{3}H]}}paroxetine

! {{verth|Selectivity
5-HTT/DAT}}

! {{verth|Selectivity
NET/DAT}}

160pxααRTI-87H3-methyl-1,2,4-oxadiazole20436K30K
160pxβαRTI-119H3-methyl-1,2,4-oxadiazole1677K41K
160pxαβRTI-124H3-methyl-1,2,4-oxadiazole102871K33K
170pxRTI-125
(32a)
Cl3-methyl-1,2,4-oxadiazole4.05 ± 0.57363 ± 362584 ± 80063789.6
145pxββRTI-126Methods for controlling invertebrate pests using cocaine receptor binding ligands. {{US patent|5935953}}
(31)
H3-methyl-1,2,4-oxadiazole100 ± 67876 ± 5513824 ± 42038.3788
170pxRTI-130
(32c)
Cl3-phenyl-1,2,4-oxadiazole1.62 ± 0.02245 ± 13195 ± 5120151
170pxRTI-141
(32d)
Cl3-(p-anisyl)-1,2,4-oxadiazole1.81 ± 0.19835 ± 8337 ± 40186461
170pxRTI-143
(32e)
Cl3-(p-chlorophenyl)-1,2,4-oxadiazole4.06 ± 0.2240270 ± 180
(4069)
404 ± 5699.59919
170pxRTI-144
(32f)
Cl3-(p-bromophenyl)-1,2,4-oxadiazole3.44 ± 0.361825 ± 170106 ± 1030.8532
170pxβRTI-151
(33)
Me3-phenyl-1,2,4-oxadiazole2.33 ± 0.2660 ± 21074 ± 13045925.7
160pxαRTI-152Me3-phenyl-1,2,4-oxadiazole4941995
170pxRTI-154
(32b)
Cl3-isopropyl-1,2,4-oxadiazole6.00 ± 0.55135 ± 133460 ± 25057722.5
160pxRTI-155Cl3-cyclopropyl-1,2,4-oxadiazole3.411774362

{{multiple image

| align = center

| perrow = 2

| image1 = RTI-470 structure.png

| width1 = 220

| caption1 = RTI-4229-470 structure. Highly excited 94 pM DAT signal.{{Cite journal

| last1 = Carroll | first1 = F.

| last2 = Howard | first2 = J.

| last3 = Howell | first3 = L.

| last4 = Fox | first4 = B.

| last5 = Kuhar | first5 = M.

| title = Development of the dopamine transporter selective RTI-336 as a pharmacotherapy for cocaine abuse

| journal = The AAPS Journal

| volume = 8

| issue = 1

| pages = E196–E203

| year = 2006

| pmid = 16584128

| doi = 10.1208/aapsj080124

| pmc = 2751440

}}

above: 2D skeletal depiction.

below: 3D tube model.

| image3 = RTI-4229-470 with tube model.png

| width3 = 220

| image4 = Heterocyclic tropanes.png

| width4 = 220

| image2 = RTI-371 structure.png

| width2 = 220

}}

class="wikitable sortable sort-under"

|+N-methylphenyltropanes with 1R β,β stereochemistry.

! Structure

! Code

! X

! 2 Group

! DAT (IC50 nM)
displacement of {{chem2|[^{3}H]}}WIN 35428

! NET (IC50 nM)
displacement of {{chem2|[^{3}H]}}nisoxetine

! 5-HTT (IC50 nM)
displacement of {{chem2|[^{3}H]}}paroxetine

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

150pxRTI-157Metetrazole1557>37K>43K
170pxRTI-163Cltetrazole9115456
170pxRTI-178Me5-phenyl-oxazol-2-yl35.46771699
170pxRTI-188Cl5-phenyl-1,3,4-oxadiazol-2-yl12.69303304
170pxRTI-189
(32i)
Cl5-phenyl-oxazol-2-yl19.7 ± 1.98496 ± 421120 ± 10756.825.5
170pxRTI-194Me5-methyl-1,3,4-oxadiazol-2-yl4.452534885
170pxRTI-195Me5-phenyl-1,3,4-oxadiazol-2-yl47.51310>22,000
170pxRTI-199Me5-phenyl-1,3,4-thiadiazol-2-yl35.9>24,000>51,000
170pxRTI-200Cl5-phenyl-1,3,4-thiadiazol-2-yl15.34142>18,000
170pxRTI-202Clbenzothiazol-2-yl1.374031119
170pxRTI-219Cl5-phenylthiazol-2-yl5.71851610,342
RTI-262Cl188.2 ± 5.01595.25 ± 57385207 ± 48831628
170pxRTI-370Me3-(p-cresyl)isoxazol-5-yl8.746980>100K
170pxRTI-371Cl3-(p-chlorophenyl)isoxazol-5-yl13>100K>100K
170pxRTI-436Me|
CH=CHPh{{Cite journal| last1 = Carroll | first1 = F.| last2 = Howard | first2 = J.| last3 = Howell | first3 = L.| last4 = Fox | first4 = B.| last5 = Kuhar | first5 = M.| title = Development of the dopamine transporter selective RTI-336 as a pharmacotherapy for cocaine abuse| journal = The AAPS Journal| volume = 8| issue = 1| pages = E196–E203| year = 2006| pmid = 16584128 | doi = 10.1208/aapsj080124| pmc = 2751440}}3.091960 (1181)335 (31)
170pxRTI-470Clo-Cl-benzothiazol-2-yl0.0941590 (994)1080 (98)
170pxRTI-451Mebenzothiazol-2-yl1.53476 (287)7120 (647)
170px32g1.28 ± 0.18504 ± 292420 ± 1361891394
170px32h12.6 ± 10.3929 ± 88330 ± 19626273.7

File:Heterocyclic phenyltropane syntheses p2.png, Kuhar, et al. {{US patent|5,935,953}} (1999).]]

N.B There are some alternative ways of making the tetrazole ring however; Cf. the sartan drugs synthesis schemes. Bu3SnN3 is a milder choice of reagent than hydrogen azide (cf. Irbesartan).

= Acyl (C2-propanoyl) =

File:WF-23.svg|

File:WF-31.svg|

File:WF-11.svg|

File:WF-33.svg|

File:3ß-(5-Indolyl)-8-azabicyclo(3.2.1)octanes.png|Indolyl{{cite journal|last1=Davies|first1=Huw M.L|last2=Ren|first2=Pingda|last3=Kong|first3=Norman|last4=Sexton|first4=Tammy|last5=Childers|first5=Steven R|title=Synthesis and monoamine transporter affinity of 3β-(4-(2-pyrrolyl)phenyl)-8-azabicyclo[3.2.1]octanes and 3β-(5-Indolyl)-8-azabicyclo[3.2.1]octanes|journal=Bioorganic & Medicinal Chemistry Letters|volume=11|issue=4|year=2001|pages=487–489|issn=0960-894X|doi=10.1016/S0960-894X(00)00701-0|pmid=11229754}}
cf. the Tamagnan series of phenyltropanes for examples with a methylene unit spacer breaking up the indole.

{{sort-under}}

class="wikitable sort-under"

!#
(#)!!X!!Y!!2 Position!!config!!8!!DA!!5-HT!!NE

WF-23
(39n)
colspan=2|β-naphthylC(O)Etβ,βNMe0.1150.394No data
WF-31 PIT |
PriHC.O.Etβ,βNMe61554.5No data
WF-11 PTT
(39e)
MeH|
C.O.Etβ,βNMe8.2131No data
WF-25
(39a)
HH|
C.O.Etβ,βNMe48.31005No data
WF-33colspan=2| 6-MeoBNC(O)Etα,βNMe0.132.24No data
colspan=9|Compound WF-11 has been shown, under consistent exposure, to elicit a biological response opposite of cocaine i.e. tyrosine hydroxylase gene expression down-regulation (instead of up-regulation as has been observed to be the case for chronic cocaine administration)

class="wikitable sortable sort-under"

|+2β-acyl-3β-phenyltropane structures{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#17 Page #941 (17th page of article)] Figure 10}}

! Structure

! S. Singh's
alphanumeric
assignation
(name)

! R1

! R2

! DAT

[125I]RTI-55 IC50 (nM)

! 5-HTT

[3H]Paroxetine Ki (nM)

! Selectivity

5-HTT/DAT

cocaine173 ± 19
Troparil
11a
(WIN 35065–2)
98.8 ± 12.2
x100pxWF-25
39a
C2H5C6H548.3 ± 2.81005 ± 11220.8
x100px39bCH3C6H5114 ± 221364 ± 61612.0
x100px39cC2H5C6H4-4-F15.3 ± 2.8630 ± 6741.2
x100px39dCH3C6H4-4-F70.8 ± 13857 ± 18712.1
rowspan=3|x100pxWF-11
39e
C2H5C6H4-4-CH38.2 ± 1.6131 ± 116.0
(+)-39eC2H5C6H4-4-CH34.21 ± 0.0574 ± 1217.6
(-)-39eC2H5C6H4-4-CH31337 ± 122>10000
x100px39fCH3C6H4-4-CH39.8 ± 0.5122 ± 2212.4
x100px39gCH3C6H4-4-C2H5152 ± 2478.2 ± 220.5
x100px39hC2H5C6H4-4-CH(CH3)2436 ± 4135.8 ± 4.40.08
x100px39iC2H5C6H4-4-C(CH3)32120 ± 6301771 ± 4740.8
x100px39jC2H5C6H4-4-C6H52.29 ± 1.084.31 ± 0.011.9
x130px39kC2H5C6H4-2-CH31287 ± 322710000>7.8
x130px39lC2H51-naphthyl5.43 ± 1.2720.9 ± 2.93.8
x130px39mCH31-naphthyl10.1 ± 2.225.6 ± 5.12.5
x100pxWF-23
39n
C2H52-naphthyl0.115 ± 0.0210.394 ± 0.0743.5
x100px39oCH32-naphthyl0.28 ± 0.111.06 ± 0.363.8
x100px39pC2H5C6H4-4-CH(C2H5)2270 ± 38540 ± 512.0
x100px39qC2H5C6H4-4-C6H11320 ± 5597 ± 120.30
x100px39rC2H5C6H4-4-CH=CH20.90 ± 0.343.2 ± 1.33.5
x100px39sC2H5C6H4-4-C(=CH2)CH37.2 ± 2.10.82 ± 0.380.1

== 2β-Acyl-3β-naphthyl substituted ==

class="wikitable sortable sort-under"

|+2β-Acyl-3β-(substituted naphthyl)-8-azabicyclo[3.2.1]octanes{{Cite journal|doi=10.1021/jm000363+|pmid=11334561|title=Synthesis of 2β-Acyl-3β-(substituted naphthyl)-8-azabicyclo[3.2.1]octanes and Their Binding Affinities at Dopamine and Serotonin Transport Sites|journal= Journal of Medicinal Chemistry|year=2001|volume= 44|issue=10|pages= 1509–1515|last1=Davies|first1=H. M.|last2=Gilliatt|first2=V|last3=Kuhn|first3=L. A.|last4=Saikali|first4=E|last5=Ren|first5=P|last6=Hammond|first6=P. S.|last7=Sexton|first7=T|last8=Childers|first8=S. R.}}

! Structure

! Short Assignation
(Numeric code, Davies UB)
S. Singh

! R

! DAT
[125H]RTI-55ɑ
IC50 nM

! SERT
[3H]paroxetineb
Ki nM

! NET
[3H]nisoxetinec
Ki nM

! potency ratio
SERT/DAT

! potency ratio
SERT/NET

File:WF-11.svgWF-11
(6)
4′-Me8.2 ± 1.6131 ± 1065 ± 9.20.060.5
File:WF-31.svgWF-31
(7)
4′-iPr436 ± 4136 ± 4>10,00012>250
File:WF-23.svgWF-23
(8)
2-naphthalene0.12 ± 0.020.39 ± 0.072.9 ± 0.50.37
x150px2β-acyl-3β-1-naphthalene
(9a)
4′-H5.3 ± 1.321 ± 2.949 ± 100.318
x150px(9b)4′-Me25.1 ± 0.58.99 ± 1.70163 ± 36318
x150px(9c)4′-Et75.1 ± 11.9175 ± 254769 ± 6880.727
x150px(9d)4′-iPr225 ± 36136 ± 64>10,0002>73.5
x110px(10a)6′-Et0.15 ± 0.040.38 ± 0.1927.7 ± 9.60.474
x110px(10b)6′-iPr0.39 ± 0.041.97 ± 0.33no data0.2
x110px(10ce)6′- OMe0.13 ± 0.042.24 ± 0.34no data0.05
x110px(10d)5′-Et, 6′-OMe30.8 ± 6.67.55 ± 1.573362 ± 1484.1445
x110px(10e)5′-C(Me)=CH2, 6′-OMe45.0 ± 3.788.0 ± 13.32334 ± 3780.526.5
x110px(10f)6′-I0.35 ± 0.070.37 ± 0.02no data1.0
x120px(10g)7′-I0.45 ± 0.050.47 ± 0.02no data0.5d
x110px(10h)5′-NO2, 6′-OMe148 ± 5015 ± 1.6no data10
x110px(10i)5′-I, 6′-OMe1.31 ± 0.332.27 ± 0.31781 ± 1810.6344
x110px(10j)5′-COMe, 6′-OMe12.6 ± 3.815.8 ± 1.65498 ± 240.832
x145px(11a)2β-COCH3, 1-naphthyl10 ± 2.226 ± 5.1165 ± 400.46.3
x135px(11b)2α-COCH3, 1-naphthyl97 ± 21217 ± 55no data0.45
x120px(11c)2α-COCH2CH3, 2-naphthyl2.51 ± 0.8216.4 ± 2.068.0 ± 10.80.154.1
x110px(11d)2β-COCH3, 2-naphthyl1.27 ± 0.151.06 ± 0.364.9 ± 1.21.24.6
x110px(11e)2β-COCH(CH3)2, 2-naphthyl0.25 ± 0.082.08 ± 0.8037.6 ± 10.50.1218.1
x110px(11f)
79a
2β-COCH2CH3, 2-naphthyl, N8-demethyl0.03 ± 0.010.23 ± 0.072.05 ± 0.90.138.9

* ɑ nonspecific binding was determined in the presence of 1.0 μM WF-23
(source equates WF-23 as analogue 3a, but table gives # as analogue 8)

  • b nonspecific binding was determined in the presence of 10.0 μM fluoxetine

|

  • c nonspecific binding was determined in the presence of 1.0 μM desipramine
  • d ratio shown as halved; a possible copy-error due to closeness to 1:1 of other indicated values
  • e sources differ on whether C2 position acyl is alpha or beta configured

= Ester reduction =

Note: p-fluorophenyl is weaker than the others. RTI-145 is not peroxy, it is a methyl carbonate.

File:RTI-123 structure.png

class="wikitable"

!Code!!X!!2 Position!!config!!8!! DA !! 5-HT !! NE

RTI-100F |
CH2OHβ,βNMe474741no data
RTI-101I |
CH2OHβ,βNMe2.226no data
RTI-99Br |
CH2OHβ,βNMe1.4951no data
RTI-93Cl |
CH2OHβ,βNMe1.5320443.8
RTI-105Cl |
CH2OAcβ,βNMe1.60143127
RTI-123Cl |
CH2OBzβ,βNMe1.783.53393
RTI-145Cl|
CH2OCO2Meβ,βNMe9.602.931.48

= 2-Alkane/Alkene =

class="wikitable sortable"

|+ 2-Alkane/Alkene-3-Phenyltropanes

! Structure

! Singh's #

! R

! X

! DAT
mazindol displacement

! DA uptake

! 5-HT Uptake

! Selectivity
DA uptake/DAT binding

File:WIN 35,065-2.svg11a
WIN 35062-2
89.453.71860.6
File:Chlorophenyltropane.png11c0.83 ± 00.728.5 ± 0.934.3
File:RTI-32 structure.png11f5.766.9223.21.2
File:Cocaine analog 41a.svg41a(CH2)2CH3H12.26.8986.80.6
File:Cocaine analog 41b.svg41b(CH2)3C6H5H16 ± 2a43 ± 13b2.7
File:Cocaine analog 42.svg42(CH2)2CH3F5.281.9921.70.4
File:Cocaine analog 43a.svg43aCH=CH2Cl0.59 ± 0.152.47 ± 0.54.2
File:Cocaine analog 43b.svg43bE-CH=CHClCl0.42 ± 0.041.13 ± 0.272.7
File:Cocaine analog 43c.svg43cZ-CH=CHClCl0.22 ± 0.020.88 ± 0.054.0
File:Cocaine analog 43d.svg43dE-CH=CHC6H5Cl0.31 ± 0.040.66 ± 0.012.1
File:Cocaine analog 43e.svg43eZ-CH=CHC6H5Cl0.14 ± 0.070.31 ± 0.092.2
File:Cocaine analog 43f.svg43fCH2CH3Cl2.17 ± 0.202.35 ± 0.521.1
File:Cocaine analog 43g.svg43 g(CH2)2CH3Cl0.94 ± 0.081.08 ± 0.051.1
File:Cocaine analog 43h.svg43h(CH2)3CH3Cl1.21 ± 0.180.84 ± 0.050.7
File:Cocaine analog 43i.svg43i(CH2)5CH3Cl156 ± 15271 ± 31.7
File:Cocaine analog 43j.svg43j(CH2)2C6H5Cl1.43 ± 0.031.54 ± 0.081.0
File:Cocaine analog 44a.svg44a(CH2)2CH3CH31.571.1010.30.7
File:Cocaine analog 44b.svg44b(CH2)3CH3CH31.821.3115.10.7
File:Cocaine analog 45.svg45(CH2)2CH3H74.930.23890.4
File:Cocaine analog 46.svg46(CH2)2CH3F21.112.199.60.6
File:Cocaine analog 47a.svg47a(CH2)2CH3CH38.9111.850.11.3
File:Cocaine analog 47b.svg47b(CH2)3CH3CH311.410.151.00.9

aKi value for displacement of WIN 35428.

bIC50 value.

{{multiple image

| align = left

| direction = horizontal

| header = Compound 48

| image1 = Compound 48-H.svg

| width1 = 220

| caption1 = para-hydro

| image2 = Compound 48-Cl.svg

| width2 = 260

| caption2 = para-chloro

}}

{{clear}}

= Irreversible covalent (''cf.'' ionic) C2 ligands =

300px

Irreversible (phenylisothiocyanate) binding ligand ({{Cite journal

| last1 = Murthy | first1 = V.

| last2 = Martin | first2 = T. J.

| last3 = Kim | first3 = S.

| last4 = Davies | first4 = H. M. L.

| last5 = Childers | first5 = S. R.

| title = In Vivo Characterization of a Novel Phenylisothiocyanate Tropane Analog at Monoamine Transporters in Rat Brain

| doi = 10.1124/jpet.108.138842

| journal = Journal of Pharmacology and Experimental Therapeutics

| volume = 326

| issue = 2

| pages = 587–595

| year = 2008

| pmid = 18492949

| s2cid = 5996473

}}){{Cite journal

| pmid = 1588560

| year = 1992

| last1 = Carroll | first1 = F. I.

| last2 = Gao

| last3 = Abraham

| last4 = Lewin

| last5 = Lew

| last6 = Patel

| last7 = Boja

| last8 = Kuhar

| title = Probes for the cocaine receptor. Potentially irreversible ligands for the dopamine transporter

| volume = 35

| issue = 10

| pages = 1813–1817

| journal = Journal of Medicinal Chemistry

| doi = 10.1021/jm00088a017

}} RTI-76:{{Cite journal

| author1 = Wu| first2 = M.| first3 = Q.| first4 = C.| first5 = F.| first6 = P.

| title = Concurrent autoreceptor-mediated control of dopamine release and uptake during neurotransmission: an in vivo voltammetric study

| journal = Journal of Neuroscience

| volume = 22

| issue = 14

| pages = 6272–6281

| year = 2002

| pmid = 12122086

| pmc = 6757948| last2 = Reith

| last3 = Walker

| last4 = Kuhn

| last5 = Carroll

| last6 = Garris

| doi = 10.1523/JNEUROSCI.22-14-06272.2002}} 4′-isothiocyanatophenyl (1R,2S,3S,5S)-3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3.2.1]octane-2-carboxylate. Also known as: 3β-(p-chlorophenyl)tropan-2β-carboxylic acid p-isothiocyanatophenylmethyl ester.

==C2 Acyl, N8 phenylisothiocyanate==

x170px

HD-205 (Murthy et al., 2007){{cite journal | doi = 10.1124/jpet.108.138842 | pmid=18492949 | volume=326 | title=In vivo characterization of a novel phenylisothiocyanate tropane analog at monoamine transporters in rat brain | date=August 2008 | journal=J. Pharmacol. Exp. Ther. | pages=587–95 | last1 = Murthy | first1 = V | last2 = Martin | first2 = TJ | last3 = Kim | first3 = S | last4 = Davies | first4 = HM | last5 = Childers | first5 = SR| issue=2 | s2cid=5996473 }}

Note the contrast to the phenylisothiocyanate covalent binding site locations as compared to the one on p-Isococ, a non-phenyltropane cocaine analogue.

= Benztropine based (C2-position hetero-substituted) phenyltropanes =

500px280px

class="wikitable sortable"

|+2-(Diarylmethoxymethyl)-3β-aryltropanes & 2β-[3-(Diarylmethoxy)propyl]-3β-aryltropanes.{{Cite journal | doi = 10.1021/jm030430a| pmid = 15027858| title = Synthesis and Monoamine Transporter Binding of 2-(Diarylmethoxymethyl)-3β-aryltropane Derivatives| journal = Journal of Medicinal Chemistry| volume = 47| issue = 7| pages = 1676–82| year = 2004| last1 = Xu | first1 = L. | last2 = Kulkarni | first2 = S. S. | last3 = Izenwasser | first3 = S. | last4 = Katz | first4 = J. L. | last5 = Kopajtic | first5 = T. | last6 = Lomenzo | first6 = S. A. | last7 = Newman | first7 = A. H. | last8 = Trudell | first8 = M. L. | url = https://figshare.com/articles/Synthesis_and_Monoamine_Transporter_Binding_of_2_Diarylmethoxymethyl_3_aryltropane_Derivatives/3345022}}{{cite journal|last1=Hong|first1=W. C.|last2=Kopajtic|first2=T. A.|last3=Xu|first3=L.|last4=Lomenzo|first4=S. A.|last5=Jean|first5=B.|last6=Madura|first6=J. D.|last7=Surratt|first7=C. K.|last8=Trudell|first8=M. L.|last9=Katz|first9=J. L.|title=2-Substituted 3 -Aryltropane Cocaine Analogs Produce Atypical Effects without Inducing Inward-Facing Dopamine Transporter Conformations|journal=Journal of Pharmacology and Experimental Therapeutics|volume=356|issue=3|year=2016|pages=624–634|issn=1521-0103|doi=10.1124/jpet.115.230722|pmid=26769919|pmc=4767397}} [https://www.ncbi.nlm.nih.gov/pubmed/26769919 nih.gov article (inclu. structural depictions)]

! Structure

! Compound

! R

! X

! Y

! [3H]WIN 35,428
@ DAT
Ki (nM)

! [3H]Citalopram
@ SERT
Ki (nM)

! [3H]Nisoxetine
@ NET
Ki (nM)

! [3H]Pirenzepine
@ M1
Ki (nM)

rowspan=10|200px
9aCH3HH34 ± 2121 ± 19684 ± 10010,600 ± 1,100
9bFHH49 ± 12
9cClHH52 ± 2.1147 ± 81,190 ± 7211,000 ± 1,290
9dCH3ClH80 ± 9443 ± 604,400 ± 23831,600 ± 4,300
9eFClH112 ± 11
9fClClH76 ± 7462 ± 362,056 ± 23639,900 ± 5,050
9gCH3FF62 ± 7233 ± 241,830 ± 17715,500 ± 1,400
9hFFF63 ± 13
9iClFF99 ± 18245 ± 162,890 ± 22216,300 ± 1,300
rowspan=7|200px
10aCH3HH455 ± 36530 ± 722,609 ± 19512,600 ± 1,790
10cClHH478 ± 72408 ± 163,998 ± 25611,500 ± 1,720
10dCH3ClH937 ± 841,001 ± 10922,500 ± 2,82118,200 ± 2,600
10fClClH553 ± 1061,293 ± 405,600 ± 1839,600 ± 600
10gCH3FF690 ± 76786 ± 6716,000 ± 6379,700 ± 900
10iClFF250 ± 40724 ± 10052,300 ± 13,6009,930 ± 1,090
rowspan=7|200px
12aHHH139 ± 1561 ± 9207 ± 307,970 ± 631
12bHClH261 ± 1945 ± 324,600 ± 2,930
12cHFF60 ± 7

= F&B series (Biotin side-chains etc.) =

One patent claims a series of compounds with biotin-related sidechains are pesticides.

class="talk collapsed collapsible"
Images of the biotin C2 side-chained phenyltropanes, click to
style="text-align: left;"

|

x170px

x170px

x170px

x170px

x240px

x200px

x290px

x290px

x280px

x240px

x200px

x200px

x260px

x260px

class="wikitable"

!Structure!!Code!!para-X!!C2-Tropane Position!!config!! DA !! NE!! 5-HT

x150pxHF1β,β
x140pxRTI-224MeF1cβ,β4.49155.6
x160pxRTI-233MeF2β,β4.3851673.6
x160pxRTI-235MeF3dβ,β1.7540272.4
x150pxF3β,β
x140pxRTI-236MeB1dβ,β1.6386.8138
x140pxRTI-237MeB2dβ,β7.27258363
x160pxRTI-244MeB3dβ,β15.6180933.7
x140pxRTI-245ClF4cβ,β77.3
RTI-246MeF4cβ,β50.33000
x150pxF5β,β
x120pxRTI-248ClF6cβ,β9.7346746.96
x140pxRTI-249ClF1cβ,β8.32502381.6
RTI-266MeF2β,β4.80836842
RTI-267MeF7 wrongβ,β2.52324455
x210pxRTI-268MeF7 rightβ,β3.891014382
x220pxRTI-269MeF8β,β5.55788986

800px

800px

= Miscellany (''i.e.'' Misc./Miscellaneous) C2-substituents =

File:Phenyltropane FMOC-hydrazide.svg

File:Phenyltropane pyrene.svg

File:Phenyltropane dimethylaminonaphthalene.svg

File:Phenyltropane pyrene hydroxamide.svg

class="wikitable"

!Structure!!Code!!X!!2 Position!!config!!8!! DA !! 5-HT !! NE

170pxRTI-102ICO2Hβ,βNMe474192843,400
170pxRTI-103BrCO2Hβ,βNMe278307017,400
170pxRTI-104FCO2Hβ,βNMe2744>100K>100K
170pxRTI-108Cl |
CH2Clβ,βNMe2.6498129.8
170pxRTI-241Me |
CH2CO2Meβ,βNMe1.02619124
170pxRTI-139Cl |
CH3β,βNMe1.678557
170pxRTI-161Cl |
C≡Nβ,βNMe13.118872516
170pxRTI-230ClH3C–C=CH2β,βNMe1.2857141
170pxRTI-240Cl |
CHMe2β,βNMe1.3838.484.5
170pxRTI-145Cl |
CH2OCO2Meβ,βNMe9.602,9321,478
170pxRTI-158Me |
C≡Nβ,βNMe5750951624
170pxRTI-131Me |
CH2NH2β,βNMe10.5855120
170pxRTI-164Me |
CH2NHMeβ,βNMe13.62246280
170pxRTI-132Me |
CH2NMe2β,βNMe3.48206137
170pxRTI-239Me |
CHMe2β,βNMe0.6111435.6
180pxRTI-338Et |
CO2CH2Phβ,βNMe11047.413366
150pxRTI-348H |
Phβ,βNMe28.2>34,0002670

C2-truncated/descarboxyl (non-ecgonine w/o 2-position-replacement tropanes)

= Aryl-Tropenes =

{{Cite patent |country= WO |number= 2004113297|title=Aza-ring derivatives and their use as monoamine neurotransmitter re-uptake inhibitors|pubdate=2004-12-29|assign=NeuroSearch AS|inventor1-last=Peters|inventor1-first=Dan |inventor2-last= Olsen|inventor2-first=Gunnar M.|inventor3-last=Nielsen|inventor3-first=Elsebet Oestergaard |inventor4-last=Scheel-Krueger|inventor4-first=Joergen}}

class="wikitable"

!Test compound!!DA-uptake IC50(μM)!!NA-uptake IC50(μM)!! 5-HT-uptake IC50(μM)

(+)-3-(4-Chlorophenyl)-8-H-aza-bicyclo[3.2.1]oct-2-ene0.260.0280.010
(+)-3-Napthalen-2-yl-8-azabicyclo[3.2.1]oct-2-ene0.0580.0130.00034
(–)-8-Methyl-3-(naphthalen-2-yl)-8-azabicylo[3.2.1]oct-2-ene0.0340.0180.00023

File:WO9713770.svg

class="wikitable" style="text-align:center"

|+ 8-AZABICYCLO[3.2.1]OCT-2-ENE DERIVATIVES

Test Compound

! DA uptake IC50(μM)

! NE uptake IC50(μM)

! 5-HT uptake IC50(μM)

(±)-3-(3,4-Dichlorophenyl)-8-methyl-8-azabicyclo[3.2.1]oct-2-ene0.0790.0260.0047

{{US patent|2001047028}}

class="wikitable"
Test Compound

! DA uptake IC50(μM)

! NE uptake IC50(μM)

! 5-HT uptake IC50(μM)

(±)-3-(4-cyanophenyl)-8-methyl-8-azabicyclo[3.2.1]oct-2-ene184.90.047
(±)-3-(4-nitrophenyl)-8-methyl-8-azabicyclo[3.2.1]oct-2-ene1.50.50.016
(±)-3-(4-trifluoromethoxyphenyl)-8-methyl-8-azabicyclo[3.2.1]oct-2-ene22.008.000.0036

Enantioselective nonstandard configurations (non-2β-,3β-)

= β,α Stereochemistry =

File:RTI-319 structure.png

File:RTI-274 Structure.png

class="wikitable"

!Structure 100px!!Compound
(RTI #)

(S. Singh's #)!!X!!2 Group!!config!!8!!DAT IC50 (nM)
[3H]WIN 35428 !!5-HTT IC50 (nM)
[3H]paroxetine !!NET IC50 (nM)
[3H]nisoxetine !! selectivity
5-HTT/DAT !! selectivity
NET/DAT

100pxRTI-140
20a
HCO2Meβ,αNMe101 ± 165,701 ± 7212,076 ± 28556.420.6
100pxRTI-352ɑ
20d
ICO2Meβ,αNMe2.86 ± 0.1664.9 ± 1.9752.4 ± 4.922.818.4
100pxRTI-549BrCO2Meβ,αNMe
100pxRTI-319b3α-2-naphthylCO2Meβ,αNMe1.1 ± 0.0911.4 ± 1.370.2 ± 6.28
100pxRTI-286c
20b
FCO2Meβ,αNMe21 ± 0.575062 ± 4851231 ± 9124158.6
140pxRTI-274dFCH2O(3′,4′-MD-phenyl)β,αNH3.965.6214.4
100pxRTI-287EtCO2Meβ,αNMe327168717,819
100px20cClCO2Meβ,αNMe2.4 ± 0.2998 ± 12060.1 ± 2.441625.0
100px20eMeCO2Meβ,αNMe10.2 ± 0.084250 ± 422275 ± 2441727.0
120pxBnCO2Meβ,αNMe

{{center|ɑ{{US Patent|6358492}}b{{US Patent|7011813}}c{{US Patent|7011813}}d{{US Patent|7291737}}}}

800px

= α,β Stereochemistry =

{{Cite patent|country=CA|number=2112084}}

File:Brasofensine.svg

File:Tesofensine chemical structure.png

File:NStwothreefivenine.png

class="wikitable"

!Compound!!DA (μM)!!M.E.D. (mg/kg)!!Dose (mg/kg)!!Activity !!Activity

(2R,3S)-2-(4-chlorophenoxymethyl)-8-methyl-3-(3-chlorophenyl)-8-azabicyclo[3.2.1]octane0.39<15000
(2R,3S)-2-(carboxymethyl)-8-methyl-3-(2-naphthyl)-8-azabicyclo[3.2.1]octane0.112500
(2R,3S)-2-(carboxymethyl)-8-methyl-3-(3,4-dichlorophenyl)-8-azabicyclo[3.2.1]octane0.0160.2550++++

== di-chloro; ''para''- & ''meta''- in tandem (α,β configured phenyltropanes) ==

{{US patent|2001047028}}

class="wikitable"

!Compound!!X!!2 Group!!config!!8!! DA!!5-HT!!NE

BrasofensineCl2methyl aldoximeα,βNMe
TesofensineCl2ethoxymethylα,βNMe65111.7
NS-2359 (GSK-372,475)Cl2Methoxymethylα,βNH

== fumaric acid salts (of α,β configured phenyltropanes) ==

{{Cite patent|country=WO|number=2004072075|title=Novel 8-aza-bicyclo[3.2.1]octane derivatives and their use as monoamine neurotransmitter re-uptake inhibitors

|pubdate=2004-08-26|assign=NeuroSearch AS|inventor1-last=Peters|inventor1-first=Dan |inventor3-last= Olsen|inventor3-first=Gunnar M.|inventor2-last=Nielsen|inventor2-first=Elsebet Oestergaard |inventor4-last=Scheel-Krueger|inventor4-first=Joergen}}

class="wikitable"
Test Compound

! DA uptake IC50(μM)

! NE uptake IC50(μM)

! 5-HT uptake IC50(μM)

(2R,3S)-2-(2,3-dichlorophenoxymethyl)-8-methyl-3-(3-chlorophenyl)-8-azabicyclo[3.2.1]octane fumaric acid salt0.0620.0350.00072
(2R,3S)-2-(Naphthaleneoxymethane)-8-methyl-3-(3-chlorophenyl)-8-azabicyclo[3.2.1]octane fumaric acid salt0.0620.150.0063
(2R,3S)-2-(2,3-dichlorophenoxymethyl)-8-H-3-(3-chlorophenyl)-8-azabicyclo[3.2.1]octane fumaric acid salt0.100.0480.0062
(2R,3S)-2-(Naphthlyloxymethane)-8-H-3-(3-chlorophenyl)-8-azabicyclo[3.2.1]octane fumaric acid salt0.0880.0510.013

Arene equivalent alterations

= ''η''<sup>6</sup>-3β-(transition metal complexed phenyl)tropanes =

File:Cocaine analog 21ab alternate.pngs and perrhenate by a double ligand transfer (DLT) reaction.{{cite journal | pmid = 11792176 | volume=13 | issue=1 | title=Synthesis of cyclopentadienyltricarbonyl rhenium phenyltropanes by double ligand transfer: organometallic ligands for the dopamine transporter | journal=Bioconjug Chem | pages=29–39 | last1 = Cesati | first1 = RR 3rd | last2 = Tamagnan | first2 = G | last3 = Baldwin | first3 = RM | last4 = Zoghbi | first4 = SS | last5 = Innis | first5 = RB | last6 = Kula | first6 = NS | last7 = Baldessarini | first7 = RJ | last8 = Katzenellenbogen | first8 = JA | doi=10.1021/bc010011x | year=2002}}]]

Unlike metal complexed PTs created with the intention of making useful radioligands, 21a & 21b were produced seeing as their η6-coordinated moiety dramatically altered the electronic character and reactivity of the benzene ring, as well as such a change adding asymmetrical molecular volume to the otherwise planar arene ring unit of the molecule. (cf. the Dewar–Chatt–Duncanson model). In addition the planar dimension of the transition metal stacked arene becomes delocalized (cf. Bloom and Wheeler.{{cite journal | journal = Angew. Chem. | year = 2011 | volume = 123 | pages = 7993–7995 | doi = 10.1002/ange.201102982 | title = Taking the Aromaticity out of Aromatic Interactions | last1 = Bloom | first1 = Jacob W. G. | last2 = Wheeler | first2 = Steven E. | issue = 34| bibcode = 2011AngCh.123.7993B }}).

21a was twice as potent as both cocaine and troparil in displacement of β-CFT, as well as displaying high & low affinity Ki values in the same manner as those two compounds. Whereas its inhibition of DA uptake showed it as comparably equipotent to cocaine & troparil. 21b by contrast had a one hundredfold decrease in high-affinity site binding compared to cocaine and a potency 10× less for inhibiting DA uptake. Attesting these as true examples relating useful effective applications for bioorganometallic chemistry.

File:Cocaine analog 21a alternate.png containing phenyltropane, having roughly twice the strength Ki affinity as parent compound at same mean affect.]]

The discrepancy in binding for the two benzene metal chelates is assumed to be due to electrostatic differences rather than their respective size difference. The solid cone angles, measured by the steric parameter (i.e. θ) is θ=131° for Cr(CO)3 whereas Cp*Ru was θ=187° or only 30% larger. The tricarbonyl moiety being considered equivalent to the cyclopenta dienyl (Cp) ligand.

File:Cocaine analog 21b alternate.png

class="wikitable sortable"

|+Displacement of Receptor-Bound [3H]WIN 35428 and Inhibition of [3H]DA Uptake by Transition Metal Complexes of 3β-Phenyltropanes

! Structure

! Compound #
(S. Singh)
Systematic name

! Ki (nM)ɑ

! IC50 (nM)

! selectivity
binding/uptake

File:Cocaine analog 21a.svg21ac17 ± 15b
224 ± 83
41824.6
File:Cocaine analog 21b.svg21bd2280 ± 18338901.7
colspan="2"|Cocaine32 ± 5
388 ±221
40512.6
colspan="2"|Troparil (11a)33 ± 17
314 ± 222
37311.3

  • ɑThe binding data fit a two-site model better than a one-site model
  • bThe Ki value for the one-site model was 124 ± 10 nM
  • cIUPAC: [η6-(2β-carbomethoxy-3β-phenyl)tropane]tricarbonylchromium
  • dIUPAC: [η5-(pentamethylcyclopentadienyl)]-[η6-(2β-carbomethoxy-3β-phenyl)tropane]ruthenium-(II) triflate

= 3-(2-thiophene) and 3-(2-furan) =

File:Cocaine analogs - thiophenes and furans.svg

{{Clear}}

class="wikitable"

! Code!!Compound!!DA (μM)!!NE (μM)!!5-HT (μM)

1(2R,3S)-2-(2,3-Dichlorophenoxymethyl)-8-methyl-3-(2-thienyl)-8-aza-bicyclo[3.2.1]octanefumaric acid salt0.300.00190.00052
2(2R,3S)-2-(1-Naphthyloxymethyl)-8-methyl-3-(2-thienyl)-8-aza-bicyclo-[3.2.1]octane fumaric acid salt0.360.00360.00042
3(2R,3S)-2-(2,3-Dichlorophenoxymethyl)-8-methyl-3-(2-furanyl)-8-aza-bicyclo-[3.2.1]octane fumaric acid salt0.310.000900.00036
4(2R,3S)-2-(1-Naphthyloxymethyl)-8-methyl-3-(2-furanyl)-8-aza-bicyclo-[3.2.1]octane fumaric acid salt0.920.00300.00053
5(2R,3S)-2-(2,3-Dichlorophenoxymethyl)-8-H-3-(2-thienyl)-8-aza-bicyclo[3.2.1]octane fumaric acid salt0.0740.00180.00074
6(2R,3S)-2-(1-Naphthyloxymethyl)-8-H-3-(2-thienyl)-8-aza-bicyclo[3.2.1]octane fumaric acid salt0.190.00160.00054

= Thiophenyltropanes =

= Diaryl =

File:Hanna et al.png|Fluoxetine homologue,[http://www.pubfacts.com/detail/23022052/A-novel-spirocyclic-tropanyl-%CE%94%C2%B2-isoxazoline-derivative-enhances-citalopram-and-paroxetine-binding- A novel spirocyclic tropanyl-Δ2-isoxazoline derivative enhances citalopram and paroxetine binding to serotonin transporters as well as serotonin uptake.] Bioorg Med Chem 2012 Nov 10;20(21):6344-55. Epub 2012 Sep 10. also: Hanna et al. (2007){{cite journal | doi = 10.1016/j.bmc.2007.08.055 | pmid=17870537 | title=Synthesis of some tropane derivatives of anticipated activity on the reuptake of norepinephrine and/or serotonin | journal=Bioorganic | date=2007 | volume=15 | issue=24 | pages=7765–7772 | first=Mona M. | last=Hanna}}
cf. the paroxetine homologue PTs

File:ZIENT.png|ZIENT:{{cite journal | doi = 10.1021/jm0100180 | pmid= 12620070 | title= Synthesis and Characterization of Iodine-123 Labeled 2β-Carbomethoxy-3β-(4′-((Z)-2-iodoethenyl)phenyl)nortropane. A Ligand for in Vivo Imaging of Serotonin Transporters by Single-Photon-Emission Tomography | journal=Journal of Medicinal Chemistry | date=2003 | volume=46 | issue=6 | pages=925–935 | first=Mark M. | last=Goodman}}

6/7-tropane position substituted

= 2β-carbomethoxy 6/7 substituted =

class="wikitable sortable"

|+6/7-Substituted 2-carbomethoxy-phenyltropanes

! Structure

! Compound #
(S. Singh)

! Substitution

! DAT (IC50 nM)
displacement of [H3]WIN 35428

! 5-HTT (IC50 nM)
[H3]Citalopram

! Selectivity
5-HTT/DAT

CocaineH65 ± 12|
160px103a3β,2β, 7-OMe
3′,4′-Cl2
86 ± 4.7884 ± 10010.3
160px103b3β,2β, 7-OH
3′,4′-Cl2
1.42 ± 0.0328.6 ± 7.820.1
130px103c3α,2β, 7-OH
3′,4′-Cl2
1.19 ± 0.161390 ± 561168
160px104a3β,2β, 6-OH
4′-Me
215ɑ|
160px104b3β,2α, 6-OH
4′-Me
15310ɑ|
130px104c3α,2β, 6-OH
4′-Me
930ɑ|
130px104d3α,2α, 6-OH
4′-Me
7860ɑ|

  • ɑIC50 value for displacement of [H3]mazindol. IC50 for cocaine 288 nM for displacement of [H3]mazindol

= 3-butyl 6/7 substituted =

class="wikitable sortable"

|+6/7-Substituted 3-butyl-phenyltropanes

! Structure

! Compound #
(S. Singh)

! Substituent

! Ki nM
displacement of [H3]mazindol binding

! Ki nM
[H3]DA uptake

! Selectivity
uptake/binding

CocaineH270 ± 0.03400 ± 201.5
x70px121a7β-CN2020 ± 10710 ± 400.3
x70px121b6β-CN3040 ± 4806030 ± 8802.0
x70px121c7β-SO2Ph4010 ± 3108280 ± 13402.1
x90px121d6β-SO2Ph4450 ± 4308270 ± 6901.8
x80px121e7α-OH830 ± 40780 ± 600.9
x130px121fH100 ± 1061 ± 100.6
x130px121g7β-CN24000 ± 342032100 ± 85401.3
x130px121h6β-CN11300 ± 154026600 ± 33302.3
x130px121i7β-SO2Ph7690 ± 27707050 ± 4500.9
x130px121j6β-SO2Ph4190 ± 7008590 ± 13602.0
x130px121k7α-SO2Ph3420 ± 1100|
x130px121l7β-SO2Ph, 7α-F840 ± 2602520 ± 2903.0
x130px121m7α-F200 ± 10680 ± 103.4
x130px121n7β-F500 ± 10550 ± 1401.1

= intermediate 6- & 7-position synthesis modified phenyltropanes =

class="wikitable sortable"

|+6/7-synthetic intermediates

! Structure

! Compound #
(S. Singh)

! Substituent W

! Substituent X

! Substituent Y

! Substituent Z

x120px(±)-122aCNHHH
x120px(±)-122bHHCHH
x120px(±)-122cHCHHH
x120px(±)-122dHHHCH
x120px(±)-122eSO2PhHHH
x120px(±)-122fHHSO2PhH
x120px(±)-122gHSO2PhHH
x120px(±)-122hSO2PhFHH
x120px(±)-122iFSO2PhHH
x120px(±)-122jHHSO2PhF

8-tropane (bridgehead) position modified

= Nortropanes (''N''-demethylated) =

File:NStwothreefivenine.png (GSK-372,475)]]

It is well established that electrostatic potential around the para position tends to improve MAT binding. This is believed to also be the case for the meta position, although it is less studied. N-demethylation dramatically potentiates NET and SERT affinity, but the effects of this on DAT binding are insignificant.{{Cite journal

| last2 = Abraham

| last6 = Carroll | first1 = B. | first2 = P. | first3 = A.

| last4 = Kuhar

| last3 = Lewin| first4 = M.

| last1 = Blough | first5 = J. | first6 = F.

| last5 = Boja

| title = Synthesis and transporter binding properties of 3β-(4′-alkyl-, 4′-alkenyl-, and 4′-alkynylphenyl)nortropane-2β-carboxylic acid methyl esters: serotonin transporter selective analogs

| journal = Journal of Medicinal Chemistry

| volume = 39

| issue = 20

| pages = 4027–4035

| year = 1996

| pmid = 8831768

| doi = 10.1021/jm960409s

| s2cid = 21616809 }} Of course, this is not always the case. For an interesting exception to this trend, see the Taxil document. There is ample evidence suggesting that N-demethylation of alkaloids occurs naturally in vivo via a biological enzyme. The fact that hydrolysis of the ester leads to inactive metabolites means that this is still the main mode of deactivation for analogues that have an easily metabolised 2-ester substituent. The attached table provides good illustration of the effect of this chemical transformation on MAT binding affinities. N.B. In the case of both nocaine and pethidine, N-demethyl compounds are more toxic and have a decreased seizure threshold.{{Cite journal

| pmid = 7205634

| date=Mar 1981 | last1 = Spealman | first1 = R. D.

| last2 = Kelleher | first2 = R. T.

| title = Self-administration of cocaine derivatives by squirrel monkeys

| volume = 216

| issue = 3

| pages = 532–536

| issn = 0022-3565

| journal = The Journal of Pharmacology and Experimental Therapeutics

}}

class="wikitable sortable"

|+Selected ββ Nortropanes

! Code
(S.S. #)

! X
para
{{smallsup|(unless position otherwise given inline)}}

! DA

! 5HT

! NE

RTI-142
75b
F4.3968.618.8
RTI-98
75d
Norɑ-RTI-55
I0.690.3611.0
RTI-110
75c
Cl0.624.135.45
RTI-173
75f
Et49.98.13122
RTI-279
Norɑ-RTI-280
para-Me
meta-I
5.98 ± 0.481.06 ± 0.1074.3 ± 3.8
RTI-305
Norɑ-RTI-360/11y
Ethynyl1.24 ± 0.111.59 ± 0.221.8 ± 1.0
RTI-307
Norɑ-RTI-281/11z
Propynyl6.11 ± 0.673.16 ± 0.33115.6 ± 5.1
RTI-309
Norɑ-11t
Vinyl1.73 ± 0.052.25 ± 0.1714.9 ± 1.18
RTI-330
Norɑ-11s
Isopropyl310.2 ± 2115.1 ± 0.97
RTI-353para-Et
meta-I
330.54 ± 17.120.69 ± 0.07148.4 ± 9.15

ɑThe N-demethylated variant of (i.e. compound code-name after dash)

class="wikitable sortable"

|+N-demethylating various β,β p-HC-phenyltropanes

!N-Me compound code#

N-demethylated derivative
compound code #

!para-X

![3H]Paroxetine

![3H]WIN 35,428

![3H]Nisoxetine

11 g75f

|Ethyl

|28.4 → 8.13

|55 → 49.9

|4,029 → 122

11t75i

|Vinyl

|9.5 → 2.25

|1.24 → 1.73

|78 → 14.9

11y75n

|Ethynyl

|4.4 → 1.59

|1.2 → 1.24

|83.2 → 21.8

11r75 g

|1-Propyl

|70.4 → 26

|68.5 → 212

|3,920 → 532

11v75k

|trans-propenyl

|11.4 → 1.3

|5.29 → 28.6

|1,590 → 54

11w75l

|cis-propenyl

|7.09 → 1.15

|15 → 31.6

|2,800 → 147

11x75 m

|Allyl

|28.4 → 6.2

|32.8 → 56.5

|2,480 → 89.7

11z75o

|1-Propynyl

|15.7 → 3.16

|2.37 → 6.11

|820 → 116

11s75h

|i-Propyl

|191 → 15.1

|597 → 310

|75,000 → ?

11u75j

|2-Propenyl

|3.13 → 0.6

|14.4 → 23

|1,330? → 144

class="wikitable"

|+N-Demethylating phenyltropanes to find a NRI

Isomer

!4′

!3′

!NE

!DA

!5HT

β,β

|Me

|H

|60 → 7.2

|1.7 → 0.84

|240 → 135

β,β

|F

|H

|835 → 18.8

|15.7 → 4.4

|760 → 68.6

β,β

|Cl

|H

|37 → 5.45

|1.12 → 0.62

|45 → 4.13

β,α

|Me

|H

|270 → 9

|10.2 → 33.6

|4250 → 500

β,α

|F

|H

|1200 → 9.8

|21 → 32.6

|5060 → 92.4

β,α

|Cl

|H

|60 → 5.41

|2.4 → 3.1

|998 → 53.3

β,α

|F

|Me

|148 → 4.23

|13.7 → 9.38

|1161 → 69.8

β,α

|Me

|F

|44.7 → 0.86

|7.38 → 9

|1150 → 97.4

"Interest in NET selective drugs continues as evidenced by the development of atomoxetine, manifaxine, and reboxetine as new NET selective compounds for treating ADHD and other CNS disorders such as depression" (FIC, et al. 2005).{{Cite journal

| last2 = Tyagi| first1 = F. | first2 = S.

| last4 = Kuhar

| last3 = Blough

| last5 = Navarro | first3 = B.

| last1 = Carroll | first4 = M. | first5 = H.

| title = Synthesis and monoamine transporter binding properties of 3α-(substituted phenyl)nortropane-2β-carboxylic acid methyl esters. Norepinephrine transporter selective compounds

| journal = Journal of Medicinal Chemistry

| volume = 48

| issue = 11

| pages = 3852–3857

| year = 2005

| pmid = 15916437

| doi = 10.1021/jm058164j

| url = https://figshare.com/articles/Synthesis_and_Monoamine_Transporter_Binding_Properties_of_3_Substituted_phenyl_nortropane_2_carboxylic_Acid_Methyl_Esters_Norepinephrine_Transporter_Selective_Compounds/3283483 }}

class="wikitable sortable"

|+N-norphenyltropanes

! Structure

! Short Name
(S. Singh)

! Para-X

! DAT
[3H]WIN 35428 IC50 (nM)

! 5-HTT
[3H]Paroxetine IC50 (nM)

! NET
[3H]Nisoxetine IC50 (nM)

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

NorcocaineH206 ± 29127 ± 13139 ± 90.60.7
x100px75aH30.8 ± 2.3156 ± 884.5 ± 7.55.12.7
x100px75bF4.39 ± 0.2068.6 ± 2.018.8 ± 0.715.64.3
x100px75cCl0.62 ± 0.094.13 ± 0.625.45 ± 0.216.78.8
x100px75dI0.69 ± 0.20.36 ± 0.057.54 ± 3.190.510.9
x110px75epara-I
&
2β-CO2CH(CH3)2
1.06 ± 0.123.59 ± 0.27132 ± 53.4124
x100px75fC2H549.9 ± 7.38.13 ± 0.30122 ± 120.22.4
x100px75gn-C3H7212 ± 1726 ± 1.3532 ± 8.10.12.5
x100px75hCH(CH3)2310 ± 2115.1 ± 0.97|
|0.05|
x100px75iCH=CH21.73 ± 0.052.25 ± 0.1714.9 ± 1.181.38.6
x100px75jC-CH3

CH2
23 ± 0.90.6 ± 0.06144 ± 120.036.3
x100px75ktrans-CH=CHCH328.6 ± 3.11.3 ± 0.154 ± 160.041.9
x100px75lcis-CH=CHCH331.6 ± 2.21.15 ± 0.1147 ± 4.30.044.6
x100px75mCH2CH=CH256.5 ± 566.2 ± 0.389.7 ± 9.60.11.6
x100px75nCH≡CH1.24 ± 0.111.59 ± 0.221.8 ± 1.01.317.6
x100px75oCH≡CCH36.11 ± 0.673.16 ± 0.33116 ± 5.10.519.0
x110px75pɑ3,4-Cl20.66 ± 0.241.4b|
|2.1|

ɑThese values determined in Cynomolgus monkey caudate-putamen

bThe radioligand used for 5-HTT was [3H]citalopram

class="wikitable sortable"

|+2β-Propanoyl-N-norphenyltropanes

! Compound Structure

! Short Name
(S. Singh)

! DAT
[125I]RTI-55 IC50 (nM)

! 5-HTT
[3H]Paroxetine Ki (nM)

! NET
[3H]Nisoxetine Ki (nM)

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

x100px79a0.07 ± 0.010.22 ± 0.162.0 ± 0.093.128.6
x100px79b4.7 ± 0.5819 ± 1.45.5 ± 2.04.01.2
x100px79c380 ± 1105.3 ± 1.03400 ± 2700.018.9
x100px79d190 ± 17150 ± 505100 ± 2200.826.8
x100px79e490 ± 12085 ± 164300 ± 11000.18.8
x100px79f1.5 ± 1.10.32 ± 0.0610.9 ± 1.50.27.3
x100px79g16 ± 4.90.11 ± 0.0294 ± 180.075.9

==Paroxetine homologues==

See the N-methyl paroxetine homologues

cf. di-aryl phenyltropanes for another SSRI approximated hybrid: the fluoxetine based homologue of the phenyltropane class.

class="wikitable sortable"

|+2-(3,4-(Methylenedioxy)phenoxy)methyl-norphenyltropane binding potencies

! Compound Structure

! Short Name
(S. Singh)

! Stereochemistry

! DAT
[3H]WIN 35428 IC50 (nM)

! 5-HTT
[3H]Paroxetine IC50 (nM)

! NET
[3H]Nisoxetine IC50 (nM)

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

x130pxParoxetine |
|623 ± 250.28 ± 0.02535 ± 150.00040.8
x130pxR-81a2β,3β835 ± 90480 ± 2137400 ± 14000.644.8
x130pxR-81b2α,3β142 ± 1390 ± 3.42500 ± 2500.617.6
x180pxR-81c2β,3α3.86 ± 0.25.62 ± 0.214.4 ± 1.31.43.7
x130pxS-81d2β,3β1210 ± 33424 ± 1517300 ± 18000.314.3
x130pxS-81e2α,3β27.6 ± 2.455.8 ± 5.731690 ± 1502.061.2
x180pxS-81f2β,3α407 ± 3319 ± 1.81990 ± 1760.054.9

= ''N''-replaced (S,O,C) =

{{multiple image

| align = center

| perrow = 2

| image1 = Phenyltropane R-97a.svg

| width1 = 220

| caption1 = R-97a (above) & S-97b (below), both examples of interim. synth. prod. in the R/S-90 & 91 series of phenyltropanes; showing the decay of the benzene structure during the synthetic process preceding the creation of like-series of PTs.

| image3 = Phenyltropane S-97b.svg

| width3 = 220

| image2 = Tropoxane.png

| width2 = 300

| image4 = Thia.png

| width4 = 400

| image5 = 10,10-dimethyl-4-((1R,5S)-8-methyl-8-azabicyclo(3.2.1)oct-2-ene-2-carbonyl)-3λ⁶-thia-4-azatricyclo(5.2.1.0¹,⁵)decane-3,3-dione.svg

| width5 = 220

| caption5 = Mid-synth stage in similar compound preparation as like to above.

| image6 = Meltzer.png

| width6 = 400

}}

The eight position nitrogen has been found to not be an exclusively necessary functional anchor for binding at the MAT for phenyltropanes and related compounds. Sulfurs, oxygens, and even the removal of any heteroatom, leaving only the carbon skeleton of the structure at the bridged position, still show distinct affinity for the monoamine transporter cocaine-target site and continue to form an ionic bond with a measurable degree of reasonable efficacy.

class="wikitable"

! Compound

! X

! 2 Group

! config

! 8

DA5-HTNE
TropoxaneCl,ClCO2Me(racemic) β,βO3.36.5No data
O-4210{{Cite journal|pmid=21146984|pmc=3015105|year=2011|last1=Purushotham|first1=M|title=The synthesis and biological evaluation of 2-(3-methyl or 3-phenylisoxazol-5-yl)-3-aryl-8-thiabicyclo3.2.1octanes|journal=Bioorganic & Medicinal Chemistry Letters|volume=21|issue=1|pages=48–51|last2=Sheri|first2=A|last3=Pham-Huu|first3=D. P.|last4=Madras|first4=B. K.|last5=Janowsky|first5=A|last6=Meltzer|first6=P. C.|doi=10.1016/j.bmcl.2010.11.076}}p-F3-methyl-5-isoxazoleβ,βS7.0>1000No data

==8-oxa bridgehead replacements==

class="wikitable sortable"

|+8-Oxanortropanes, binding inhibition using monkey caudate-putamen

! Structure

! Compound #
(S. Singh)

! Para-
(meta-)

! DAT (IC50 nM)
displacement of [H3]WIN 35428

! 5-HTT (IC50 nM)
[H3]Citalopram

! Selectivity
5-HTT/DAT

120pxR/S-90aH>1000>1000|
140pxR/S-90bF54625804.7
140pxR/S-90cCl1010710.7
140pxR/S-90dBr22301.4
140pxR/S-90eI7121.7
140pxR/S-90f3,4-Cl23.356.521.9
140pxR-90g3,4-Cl23.274.671.4
140pxS-90h3,4-Cl247581.2
90pxR/S-91aH1990114405.7
90pxR/S-91bF>1000>10000|
90pxR/S-91cCl28.581628.6
90pxR/S-91dBr927630.7
90pxR/S-91eI42721.7
100pxR/S-91f3,4-Cl23.0864.520.9
100pxR-91g3,4-Cl22.343113.2
100pxS-91h3,4-Cl256286051.1

==8-carba bridgehead replacements==

class="wikitable sortable"

|+8-carba 3-Aryl bicyclo[3.2.1]octanes

! Structure

! Compound #
(S. Singh)

! DAT (IC50 nM)
displacement of [H3]WIN 35428

! 5-HTT (IC50 nM)
[H3]Citalopram

! Selectivity
5-HTT/DAT

140pxR/S-98a7.1 ± 1.75160 ± 580726
140pxR/S-98b9.6 ± 1.833.4 ± 0.63.5
100pxR/S-98c14.3 ± 1.1180 ± 6512.6

= ''N''-alkyl =

File:RTI-242 structure.png

File:Altropane.svg

File:Ioflupane.png

class="wikitable"

!Compound!!X!!2 Group!!config!!8!! DAT!!SERT!!NET

FP-β-CPPITCl3′-phenylisoxazol-5′-ylβ,βNCH2CH2CH2F---
FE-β-CPPITCl(3′-phenylisoxazol-5′-yl)β,βNCH2CH2F---
Altropane (IACFT)FCO2Meβ,βNCH2CH=CHF---
FECNT{{cite journal|last1=Wu|first1=Xiaoai|last2=Cai|first2=Huawei|last3=Ge|first3=Ran|last4=Li|first4=Lin|last5=Jia|first5=Zhiyun|title=Recent Progress of Imaging Agents for Parkinson's Disease|journal=Current Neuropharmacology|volume=12|issue=6|year=2015|pages=551–563|issn=1570-159X|doi=10.2174/1570159X13666141204221238|pmc=4428027|pmid=25977680}}ICO2Meβ,βNCH2CH2F---
RTI-310 {{US patent|5736123}}ICO2Meβ,βN-Prn1.17--
RTI-311ICO2Meβ,βNCH2CH=CH21.79--
RTI-312 {{US patent|5736123}}ICO2Meβ,βNBun0.76--
RTI-313 {{US patent|5736123}}ICO2Meβ,βNCH2CH2CH2F1.67--
Ioflupane (FP-CIT)123ICO2Meβ,βNCH2CH2CH2F---
PE2IMeCO2Meβ,βNCH2CH=CHI---
RTI-251ClCO2Meβ,βNCH2CO2Et1.9310.1114
RTI-252ClCO2Meβ,βNCH2CH2CO2Et2.5635.2125
RTI-242Clcolspan=3| β,β (bridged) -C(O)CH(CO2Me)CH2N7.67227510

Bi- and tri-cyclic aza compounds and their uses.{{US patent|6150376}}{{Cite patent|country=WO|number=0007994|title=Novel bi- and tri-cyclic aza compounds and their uses|pubdate=2000-02-17|assign=Georgetown University|inventor1-last=Kozikowski|inventor1-first=Alan P.|inventor2-last=Smith|inventor2-first=Miles P.}}

class="wikitable sortable"

|+N-substituted 3β-phenylnortropanes
(including N-phthalimidoalkyl analogues of β-CIT)

! Structure

! Short Name
(S. Singh)

! Nitrogen side-chain
(N8)

! DAT
[3H]GBR 12935 Ki (nM)

! 5-HTT
[3H]Paroxetine Ki (nM)

! NET
[3H]Nisoxetine Ki (nM)

! Selectivity
5-HTT/DAT

! Selectivity
NET/DAT

CocaineH350 ± 80>10000>30000>28.6|
GBR 12909 |
|0.06 ± 0.0252.8 ± 4.4>20000880|
WIN 35428
11b
H14.7 ± 2.9181 ± 21635 ± 11012.343.2
RTI-55
11e
H1.40 ± 0.200.46 ± 0.062.80 ± 0.400.32
150px82aCH2CH=CH222.6 ± 2.9ɑ|
150px82bCH2CH2CH343.0 ± 17.7ɑ|
160px82cCH2C6H558.9 ± 1.65b1073c|
|18.2|
200px82d(CH2)3C6H51.4 ± 0.2b133 ± 7c|
|95.0|
210px82e(CH2)5C6H53.4 ± 0.83b49.9 ± 10.2c|
|14.7|
160px83aCH2CH2CH2F1.20 ± 0.2948.7 ± 8.41000040.68333
160px83bCH2CH2F4.40 ± 0.3521.7 ± 8.3>100004.9|
160px84aCH2CH2CH2F3.50 ± 0.390.110 ± 0.0263.0 ± 4.00.0318
160px84bCH2CH2F4.00 ± 0.730.140 ± 0.0293.0 ± 17.00.0323.2
160px84cCH2CHF215.1 ± 3.79.6 ± 1.5>50000.6|
170px84dCH2CH2CH2Cl3.10 ± 0.570.32 ± 0.0696.0 ± 29.00.131.0
170px84eCH2CH2CH2Br2.56 ± 0.570.35 ± 0.08164 ± 470.164.1
170px84fCH2CH2CH2I38.9 ± 6.38.84 ± 0.5350000.2128
170px84gCH2...methylcyclopropane4.30 ± 0.871.30 ± 0.25198 ± 9.60.346.0
180px84hCH2CH2CH2OH5.39 ± 0.212.50 ± 0.20217 ± 190.540.2
200px84iCH2CH2(OCH3)26.80 ± 1.101.69 ± 0.09110 ± 7.70.216.2
180px84jCH2CO2CH311.9 ± 1.40.81 ± 0.1029.1 ± 1.00.072.4
185px84kCH2CON(CH3)212.2 ± 3.86.40 ± 1.70522 ± 1450.542.8
200px84lCH2CH2CH2OMs36.3 ± 2.117.3 ± 1.250000.5138
170px84mCOCH(CH3)22100 ± 140102 ± 23>100000.05|
210px84n(CH2)2Pht4.23 ± 0.480.84 ± 0.02441 ± 66.00.2104
210px84o(CH2)3Pht9.10 ± 1.100.59 ± 0.0774.0 ± 11.60.068.1
230px84p(CH2)4Pht2.38 ± 0.220.21 ± 0.02190 ± 18.00.0979.8
230px84q(CH2)5Pht2.40 ± 0.170.34 ± 0.0360.0 ± 3.100.125.0
270px84r(CH2)8Pht2.98 ± 0.300.20 ± 0.0275.0 ± 3.60.0725.2
170px84sdCH2CH=CH-CH315 ± 175 ± 5400 ± 805.026.7
170px84tdCH2C(Br)=CH230 ± 5200 ± 40>10006.7|
170px84udCH2CH=CH2I(E)30 ± 5960 ± 60295 ± 3332.09.8
170px84vdCH2C≡CH14 ± 1100 ± 30>10007.1|
170px84wdCH2C6H542 ± 12100 ± 17600 ± 1002.414.3
170px84xdCH2C6H4-2-CH393 ± 19225 ± 40>10002.4|
160px85adpara-H113 ± 41100 ± 20>10000.9|
170px85bdpara-Cl, meta-Cl29 ± 450 ± 6500 ± 1201.717.2
170px85cdpara-Me17 ± 7500 ± 30>100029.4|
180px85ddpara-CH(CH3)2500 ± 120450 ± 80>10000.9|
190px85edpara-n-C3H7500 ± 100300 ± 12750 ± 1600.61.5

  • ɑIC50 for displacement of [3H]cocaine. IC50 for cocaine = 67.8 ± 8.7 (nM)
  • bIC50 values for displacement of [3H]WIN 35428
  • cIC50 values for displacement of [3H]citalopram
  • dThe standard Ki value for the displacement of [3H]GBR 12935, [3H]paroxetine, and [3H]nisoxetine were 27 ± 2, 3 ± 0.2, and 80 ± 28 nM, respectively, for these experiments

class="wikitable sortable"

|+3β-(4-alkylthiophenyl)nortropanes

! Structure 150px

! Compound

! R1

! R2

! Inhibition of [3H]WIN 35,428
@ DAT
IC50 (nM)

! Inhibition of [3H]Paroxetine
@ 5-HTT
Ki (nM)

! Inhibition of [3H]Nisoxetine
@ NET
Ki (nM)

! NET/DAT
(uptake ratio)

! NET/5-HTT
(uptake ratio)

rowspan=3|See 7a—7h table
7aCH3CH39 ± 30.7 ± 0.2220 ± 1024314
7bC2H5CH3232 ± 344.5 ± 0.51170 ± 3005260
160px8aCH3H28 ± 60.19 ± 0.0121 ± 60.8110
170px8bC2H5H177 ± 621.26 ± 0.05118 ± 130.794
210px9aCH3FCH2CH2CH2112 ± 23 ± 1960 ± 1009320
215px9bC2H5FCH2CH2CH21,200 ± 20027 ± 2>2,000274
200px10aCH3CH2=CH2CH271 ± 255.5 ± 0.82,000 ± 50028364
205px10bC2H5CH2=CH2CH21,100 ± 10047 ± 3>2,000243
200px11aCH3CH3CH2CH274 ± 205.7 ± 0.61,200 ± 14016211
205px11bC2H5CH3CH2CH2900 ± 30049 ± 6>2,000241

= Bridged ''N''-constrained phenyltropanes (fused/tethered) =

== ''p''-methyl aryl front & back ''N''-bridged phenyltropanes ==

{{US patent|6150376}}

File:Koz US6150376.png

{{multiple image|total_width=660|perrow=2|align=center

|image1=Alt2D-bridged-phenyltropane-no42a.png|width1=325|caption1=Alternate 2D rendering of compound "42a" (from among the above 'bridged' phenyltropanes) to elucidate the potential overlaying structure of the place inhabited by the constrained nitrogen. Compare JNJ-7925476, tametraline and similar compounds.

|image2=RTI-4229-242.png|width2=325|caption2=RTI-242

}}

{{sort-under}}

class="wikitable sortable sort-under"

|+Activity at monoamine transporters: Binding Affinities & MAT Inhibition of Bridged Phenyltropanes Ki (nM)

!Compound #
(S. Singh's #)

!2β=R

![3H]Mazindol
binding

![3H]DA
uptake

![3H]5-HT
uptake

![3H]NE
uptake

!selectivity
[3H]5-HT/[3H]DA

cocaineCO2CH3375 ± 68423 ± 147155 ± 4083.3 ± 1.50.4
(–)-40
(–)-128
54.3 ± 10.260.3 ± 0.41.76 ± 0.235.24 ± 0.070.03
(+)-40
(+)-128
79 ± 19114 ± 281.48 ± 0.074.62 ± 0.310.01
(±)-40
(±)-128
61.7 ± 8.560.3 ± 0.42.32 ± 0.232.69 ± 0.120.04
29β62014208030
30β18649297.7
31β47.021128.5
29α4140201003920
30α396088506961150
45
129
6.86 ± 0.4324.0 ± 1.31.77 ± 0.041.06 ± 0.030.07
42a
131a
n-Bu4.00 ± 0.072.23 ± 0.1214.0 ± 0.62.99 ± 0.176.3
41a
130a
n-Bu17.2 ± 1.1310.2 ± 1.478.9 ± 0.915.0 ± 0.47.8
42b
131b
Et3.61 ± 0.4311.3 ± 1.125.7 ± 4.34.43 ± 0.012.3
50a
133a
n-Bu149 ± 6149 ± 2810 ± 8051.7 ± 125.4
49a
132a
n-Bu13.7 ± 0.814.2 ± 0.1618 ± 873.84 ± 0.3543.5
(–)-41050016500189070900
(+)-41850027600463038300
(–)-597409050119004650
(+)-5677010500251004530
RTI-4229/Coc-242N8/2β-C(O)CH(CO2Me)CH2N para-chloro7.67 ± 0.31ɑ226.54 ± 27.37b510.1 ± 51.4c

  • ɑValue for displacement of [3H]WIN 35,428 binding @ DAT
  • bValue for displacement of [3H]paroxetine binding to SERT
  • cValue for displacement of [3H]nisoxetine from NET

Fused tropane-derivatives as neurotransmitter reuptake inhibitors. Singh notes that all bridged derivatives tested displayed 2.5—104 fold higher DAT affinity than cocaine. The ones 2.8—190 fold more potent at DAT also had increased potency at the other two MAT sites (NET & SERT); NET having 1.6—78× increased activity. (+)-128 additionally exhibited 100× greater potency @ SERT, whereas 132a & 133a had 4–5.2× weaker 5-HTT (i.e. SERT) activity. Front-bridged (e.g. 128 & 129) had a better 5-HT/DA reuptake ratio in favor of SERT, while the back-bridged (e.g. 130–133) preferred placement with DAT interaction.

{{US patent|5998405}}

== 3,4-Cl<sub>2</sub> aryl front-bridged phenyltropanes ==

File:Fused Tropane.png A/S, Scheel-Krüger et al. {{US patent|5998405}}]]

File:Phenyltropane 140.svg

class="wikitable"

! Code!!Compound!!DA (μM)!!NE (μM)!!5-HT (μM)

1(1 S,2S,4S,7R)-2-(3,4-Dichloro- phenyl)-8-azatricyclo[5.4.0.04,8]- undecan-11 -one O-methyl-oxime0.0120.00200.0033
2(1 S,2S,4S,7R)-2-(3,4-Dichloro- phenyl)-8-azatricyclo[5.4.0.04,8]- undecan-11-one0.180.0350.0075
3(1 S,3S,4S,8R)-3-(3,4-Dichloro-phenyl)-7-azatricyclo[5.3.0.04,8]- decan-5-one O-methyl-oxime0.01600.00090.0032
4(1 S,2S,4S,7R)-2-(3,4-Dichloro-phenyl)-8-azatricyclo[5.4.0.04,8]- undecan-11-ol0.07500.00410.0028
5(1 S,3S,4S,8R)-3-(3,4-Dichloro-phenyl)-7-azatricyclo[5.3.0.04,8]- decan-5-one0.120.00520.0026
6(1 S,3S,4S,8R)-3-(3,4-Dichloro- phenyl)-7-azatricyclo[5.3.0.04,8]-decan-5-ol0.250.00740.0018
7(1S,3S,4S,8R)-3- (3,4-Dichloro- phenyl)-7-azatricyclo[5.3.0.04,8]dec- 5-yl acetate0.210.00610.0075
8(1S,3S,4S,8R)-3-(3,4-Dichlorophenyl)-5-methoxy-7- azatricyclo[5.3.0.04,8]decane0.0220.00140.0001

  1. 1-Chloroethyl chloroformate is used to remove N-methyl of trans-aryltropanes.
  2. 2° amine is reacted with Br(CH2)nCO2Et.
  3. Base used to abstract proton α- to CO2Et group and complete the tricyclic ring closure step (Dieckmann cyclization).

To make a different type of analog (see Kozikowski patent above)

  1. Remove N-Me
  2. Add ɣ-bromo-chloropropane
  3. Allow for cyclization with K2CO3 base and KI cat.

==C2 + C3 (side-chain) fused (carboxylate & benzene conjoined)==

File:(3S,5S,8R)-3-(4-methylphenyl)-9,18-diazapentacyclo(9.7.0.0²,⁸.0⁵,⁹.0¹²,¹⁷)octadeca-1(11),12(17),13,15-tetraene.svg

250px

(1R,2S,10R,12S)-15-methyl-15-azatetracyclo(10.2.1.02,10.04,9)pentadeca-4(9),5,7-trien-3-one

==C3 to 1′ + 2′ (''ortho'') tropane locant dual arene bridged==

250px

Parent compound of a series of spirocyclic cocaine benzoyl linkage modification analogs created by Suzuki coupling method of ortho-substituted arylboronic acids and an enol-triflate derived from cocaine; which technically has the three methylene length of cocaine analogues as well as the single length which defines the phenyltropane series. Note that the carbomethoxyl group is (due to constraints in synthetic processes used in the creation of this compound) alpha configured; which is not the usual, most prevalent, conformation favored for the PT cocaine-receptor binding pocket of most such sub-type of chemicals. The above and below depictions show attested compounds synthesized, additionally with variations upon the Endo–exo isomerism of their structures.{{cite journal | last1 = Sakamuri | first1 = Sukumar |display-authors=etal | year = 2000 | title = Synthesis of novel spirocyclic cocaine analogs using the Suzuki coupling | journal = Tetrahedron Letters | volume = 41 | issue = 13| pages = 2055–2058 | doi = 10.1016/S0040-4039(00)00113-1 }}

250px

Cycloalkane-ring alterations of the tropane ring system

= Azanonane (outer ring extended) =

3-Phenyl-9-azabicyclo[3.3.1]nonane derivatives

To better elucidate the binding requirements at MAT, the methylene unit on the tropane was extended by one to create the azanonane analogs.{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#43 Page #967 (43rd page of article)] 2nd column}} Which are the beginning of classes of modifications that start to become effected by the concerns & influences of macrocyclic stereocontrol.

Despite the loosened flexibility of the ring system, nitrogen constrained variants (such as were created to make the bridged class of phenyltropanes) which might better fit the rigid placement necessary to suit the spatial requirements needed in the binding pocket were not synthesized. Though front-bridged types were synthesized for the piperidine homologues: the trend of equal values for either isomers of that type followed the opposing trend of a smaller and lessened plasticity of the molecule to contend with a rationale for further constraining the pharmacophore within that scope. Instead such findings lend credence to the potential for the efficacy of fusing the nitrogen on an enlarged tropane, as like upon the compounds given below.

class="wikitable sortable"

|+[3.3.1]azanonane analogues
displacement of bound [3H]WIN 35428

! Structure

! Compound #
(S. Singh)

! Ki (nM)

File:Kokain - Cocaine.svgCocaine32 ± 5
390 ± 220
File:WIN 35,065-2.svgWIN 35065-233 ± 17
310 ± 220
File:Cocaine analog 146a.svg146a4600 ± 510
File:Cocaine analog 146b.svg146b5730 ± 570
File:Cocaine analog 146c.svg146c3450 ± 310
File:Cocaine analog 146d.svg146d3470 ± 350
File:Cocaine analog 147.svg14713900 ± 2010

= Azabornane (outer ring contracted) =

3-Phenyl-7-azabicyclo[2.2.1]heptane derivatives

Ring-contracted analogs of phenyltropanes did not permit sufficient penetration of the phenyl into the target binding site on MAT for an affinity in the efficacious range. The distance from the nitrogen to the phenyl centroid for 155a was 4.2 and 155c was 5.0 Å, respectively. (Whereas troparil was 5.6 & compound 20a 5.5 angstroms). However piperidine homologues (discussed below) had comparable potencies.{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#43 Page #967 (43rd page of article)] 2nd column}}

File:2-exo-phenyl-7-azabicyclo(2-2-1)heptane.png releaser of MAT & VMAT, yet similar to phenyltropanes (that usually are only re-uptake ligands)[http://www.ingentaconnect.com/content/els/00404039/1995/00000036/00000039/art01414 exo-2-Phenyl-7-azabicyclo[2.2.1]heptane-1-carboxylic Acid: A New Constrained Proline Analogue.] Source: Tetrahedron Letters, Volume 36, Number 39, 25 September 1995, pp. 7123-7126(4) cf. EXP-561 & BTQ.]]

Azabornanes with longer substitutions at the 3β-position (benzoyloxys alkylphenyls, carbamoyls etc.) or with the nitrogen in the position it would be on the piperidine homologues (i.e. arrangements of differing locations for the nitrogens being either distal or proximal within the terms required to facilitate the framework of the compound to a correlative proportion, functional for the given moiety), were not synthesized, despite conclusions that the nitrogen to phenyl length was the issue at variance enough to be the interfering factor for the proper binding of the compressed topology of the azabornane. Carroll, however, has listed benzoyloxy azabornanes in patents.

class="wikitable sortable"

|+[2.2.1]azabornane analogues
displacement of bound [3H]WIN 35428

! Structure

! Compound #
(S. Singh)

! Ki (nM)

File:Kokain - Cocaine.svgCocaine32 ± 5
390 ± 220
File:WIN 35,065-2.svgWIN 35065-233 ± 17
310 ± 220
File:Cocaine analog 155a.svg155a60,400 ± 4,800
File:Cocaine analog 155b.svg File:Cocaine analog 155b alt.svg155b96,500 ± 42
File:Cocaine analog 155c.svg155c5,620 ± 390
File:Cocaine analog 155d.svg155d18,900 ± 1,700

= Piperidine [[Homologous series|homologues]] (inner two-carbon bridge excised) =

Piperidine homologues had comparable affinity & potency spreads to their respective phenyltropane analogues. Without as much of a discrepancy between the differing isomers of the piperidine class with respect to affinity and binding values as had in the phenyltropanes.

== distal-nitrogen 'dimethylamine' (piperidine-like cyclohexyl homologues of phenyltropanes) ==

Radiolabeled

File:Radiolabel Tropane.png

File:LBT-999.svg, a radio-ligand.]]

class="wikitable"

! Code!!SERT Ki (nM)!!NET Ki (nM)!!DAT Ki (nM)!!Radiolabel!!In vivo study!!Refs.

10.2102.229.911CNon-human primate{{cite journal | doi = 10.1021/jm060641q | pmid= 17154506 | title= Synthesis, Radiosynthesis, and Biological Evaluation of Carbon-11 Labeled 2β-Carbomethoxy-3β-(3′-(( Z )-2-haloethenyl)phenyl)nortropanes: Candidate Radioligands for in Vivo Imaging of the Serotonin Transporter with Positron Emission Tomography | journal=Journal of Medicinal Chemistry | date=2006 | volume=49 | issue=23 | pages=6760–6767 | first=Jeffrey S. | last=Stehouwer| url= https://figshare.com/articles/Synthesis_Radiosynthesis_and_Biological_Evaluation_of_Carbon_11_Labeled_2_Carbomethoxy_3_3_i_Z_i_2_haloethenyl_phenyl_nortropanes_Candidate_Radioligands_for_in_Vivo_Imaging_of_the_Serotonin_Transporter_with_Positron_Emission_Tomography/3047263 }}
20.231.732.611CNon-human primate{{cite journal | doi = 10.1016/j.bmcl.2007.03.040 | title=Conformationally restricted homotryptamines 3. Indole tetrahydropyridines and cyclohexenylamines as selective serotonin reuptake inhibitors | journal=Bioorganic & Medicinal Chemistry | date=2007 | volume=17 | issue=11 | pages=3099–3104 | first=Jeffrey A. | last=Deskus | pmid=17391962}}
30.05243.47123IRat{{cite journal | doi = 10.1016/j.bmcl.2005.01.059 | pmid=15745809 | title=Homotryptamines as potent and selective serotonin reuptake inhibitors (SSRIs) | journal=Bioorganic & Medicinal Chemistry| date=2005 | volume=15 | issue=6 | pages=1619–1621 | first=William D. | last=Schmitz}}
40.08281318FNon-human primate{{cite journal | doi = 10.1021/jm061303s | pmid= 17705359 | title= Synthesis and in Vivo Evaluation of Fluorine-18 and Iodine-123 Labeled 2β-Carbo(2-fluoroethoxy)-3β-(4′-(( Z )-2-iodoethenyl)phenyl)nortropane as a Candidate Serotonin Transporter Imaging Agent | journal=Journal of Medicinal Chemistry | date=2007 | volume=50 | issue=19 | pages=4553–4560 | first=Christophe | last=Plisson}}
50.114502211CRat, monkey{{cite journal|pmc=2671940|year=2006|last1=McMahon|first1=C. G.|title=New agents in the treatment of premature ejaculation|journal=Neuropsychiatric Disease and Treatment|volume=2|issue=4|pages=489–503|last2=McMahon|first2=C. N.|last3=Leow|first3=L. J.|pmid=19412497|doi=10.2147/nedt.2006.2.4.489 |doi-access=free }}

File:N-3-iodoprop-(2E)-ene-2β-carbomethoxy-3β-(4′-chlorophenyl)tropane.png|IPT (N-3-iodoprop-(2E)-ene-2β-carbomethoxy-3β-(4′-chlorophenyl)tropane), can be radiolabeled with 123I or 125I and used as a ligand to map several MATs

File:N-4-Fluorobut-2-yn-1-yl-2β-carbomethoxy-3β-phenyltropane.png|N-4-Fluorobut-2-yn-1-yl-2β-carbomethoxy-3β-phenyltropane (PR04.MZ) often radiolabeled.{{cite journal | pmid = 22073420 | title=N-4-Fluorobut-2-yn-1-yl-2β-carbo-[11C]methoxy-3β-phenyltropane | last1 = Leung | first1 = K | year=2004}}{{cite journal | pmid = 2207342 | volume=61 | issue=2–3 | title=Treatment of refractory multiple myeloma with the vincristine-adriamycin-dexamethasone (VAD) regimen | journal=Blut | pages=55–9 | last1 = Stenzinger | first1 = W | last2 = Blömker | first2 = A | last3 = Hiddemann | first3 = W | last4 = de Loo | first4 = J | doi=10.1007/bf02076700 | year=1990| s2cid=25860357 }}

File:JHC 1-64.svg|JHC1-64.{{cite journal| pmc=5511133 | pmid=28710426 | doi=10.1038/s41598-017-05637-x | bibcode=2017NatSR...7.5399M | volume=7 | issue=1 | title=Targeting of dopamine transporter to filopodia requires an outward-facing conformation of the transporter | year=2017 | journal=Sci Rep | page=5399 | last1 = Ma | first1 = S | last2 = Cheng | first2 = MH | last3 = Guthrie | first3 = DA | last4 = Newman | first4 = AH | last5 = Bahar | first5 = I | last6 = Sorkin | first6 = A}} A fluorescent analog, similar in its long chain off of the nitrogen bridge similar to the transition metal phenyltropane types.

= Transition metal complexes =

These compounds include transition metals in their heteroatomic conformation, unlike non-radiolabel intended chelates where their element is chosen for intrinsic affectation to binding and function, these are tagged on by a "tail" (or similar) with a sufficient spacer to remain separated from known binding properties and instead are meant to add radioactivity enough to be easily tracked via observation methods that utilize radioactivity. As for anomalies of binding within the spectrum of the under-written kinds just mentioned: other factors not otherwise considered to account for its relatively lower potency, "compound 89c" is posited to protrude forward at the aryl place on its moiety toward the MAT ligand acceptor site in a manner detrimental to its efficacy. That is considered due to the steric bulk of the eight-position "tail" chelate substituted constituent, overreaching the means by which it was intended to be isolated from binding factors upon a tail, and ultimately nonetheless, interfering with its ability to bind. However, to broach this discrepancy, decreasing of the nitrogen tether at the eight position by a single methylene unit (89d) was shown to bring the potency of the analogous compound to the expected, substantially higher, potency: The N-methyl analog of 89c having an IC50 of 1.09 ± 0.02 @ DAT & 2.47 ± 0.14 nM @ SERT; making 89c upwards of thirty-three times weaker at those MAT uptake sites.{{efn| ←[https://www.erowid.org/archive/rhodium/pdf/cocaineanalogs.pdf#31 Page #955 (31st page of article)] 1st (left) column, 2nd ¶}}

class="wikitable sortable"

|+"Transition metal" chelated phenyltropanes

! Structure

! Compound #
(S. Singh)

! X = para- / 4′-
Substitution

! Configuration

! DAT (IC50 nM)
displacement of [H3]WIN 35428

! 5-HTT (IC50 nM)
[H3]Citalopram

! Selectivity
5-HTT/DAT

File:Phenyltropane 11b - WIN 35428.svgWIN 35428F-11.0 ± 1.0160 ± 2014.5
+2β-chelated phenyltropanes
File:Cocaine analog 73 - TRODAT-1.svg73
TRODAT-1ɑ
Cl-R=13.9, S=8.42b|
File:Cocaine analog 74 - TROTEC-1.svg74
TROTEC-1
F-high affinity site = 0.15 ± 0.04c
low affinity site = 20.3 ± 16.1c|
colspan=7 style="text-align:center;" |N-chelated phenyltropanes
File:Cocaine analog 89a.svg89aF5.99 ± 0.81124 ± 1720.7
File:Cocaine analog 89b.svg89bF2960 ± 1575020 ± 18801.7
File:Cocaine analog 89c.svg89c3,4-Cl237.2 ± 3.4264 ± 167.1
File:Cocaine analog 89d.svg89dCl-0.31 ± 0.03d- |

  • ɑIUPAC: [2-[[2-[[[3-(4-chlorophenyl)-7-methyl-8-azabicyclo[3,2,1]oct-2-yl]methyl]-(2-mercaptoethyl)amino]ethyl]amino]ethanethiolato-(3—)-N2, N2′, S2, S2′]oxo-[1R-(exo, exo)]-[99mTc]technetium
  • bR- & S- isomer values are Ki (nM) for displacement of [125I]IPT with technetium-99m replaced by rhenium
  • cIC50 (nM) values for displacement of [3H]WIN 35428 with ligand tricarbonyltechnetium replaced with rhenium. (IC50 for WIN 35428 were 2.62 ± 1.06 @ high affinity binding & 139 ± 72 @ low affinity binding sites)
  • dKi value for displacement of [125I]IPT radioligand.

{{clear}}

Select annotations of above

Phenyltropanes can be grouped by "N substitution" "Stereochemistry" "2-substitution" & by the nature of the 3-phenyl group substituent X.

Often this has dramatic effects on selectivity, potency, and duration, also toxicity, since phenyltropanes are highly versatile. For more examples of interesting phenyltropanes, see some of the more recent patents, e.g. {{US Patent|6329520}}, {{US Patent|7011813}}, {{US Patent|6531483}}, and {{US Patent|7291737}}.

Potency in vitro should not be confused with the actual dosage, as pharmacokinetic factors can have a dramatic influence on what proportion of an administered dose actually gets to the target binding sites in the brain, and so a drug that is very potent at binding to the target may nevertheless have only moderate potency in vivo. For example, RTI-336 requires a higher dosage than cocaine. Accordingly, the active dosage of RTI-386 is exceedingly poor despite the relatively high ex vivo DAT binding affinity.

Sister substances

Many molecular drug structures have exceedingly similar pharmarcology to phenyltropanes, yet by certain technicalities do not fit the phenyltropane moniker. These are namely classes of dopaminergic cocaine analogues that are in the piperidine class (a category that includes methylphenidate) or benztropine class (such as Difluoropine: which is extremely close to fitting the criteria of being a phenyltropane.) Whereas other potent DRIs are far removed from being in the phenyltropane structural family, such as Benocyclidine or Vanoxerine.

Most any variant with a tropane locant—3-β (or α) connecting linkage differing from, e.g. longer than, a single methylene unit (i.e. "phenyl"), including alkylphenyls (see the styrene analog, first image given in example below) is more correctly a "cocaine analogue" proper, and not a phenyltropane. Especially if this linkage imparts a sodium channel blocker functionality to the molecule.

See also

References

= Citations =

{{Reflist}}