Ascomycin

{{Short description|Chemical compound}}

{{Drugbox

| Verifiedfields = changed

| verifiedrevid = 457820106

| IUPAC_name = (3S,4R,5S,8R,9Z,12S,14S,15R,16S,18R,19R,26aS)-8-ethyl-5,19-dihydroxy-3-{(E)-2-[(1R,3R,4R)-4-hydroxy-3-methoxycyclohexyl]-1-methylvinyl}-14,16-dimethoxy-4,10,12,18-tetramethyl-4,5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a-heptadecahydro-3H-15,19-epoxypyrido[2,1-c][1,4]oxazacyclotricosine-1,7,20,21(23H)-tetrone

| image = Ascomycin structure.png

| tradename =

| pregnancy_AU =

| pregnancy_US =

| pregnancy_category =

| legal_AU =

| legal_CA =

| legal_UK =

| legal_US =

| legal_status =

| routes_of_administration =

| bioavailability =

| protein_bound =

| metabolism =

| elimination_half-life =

| excretion =

| CAS_number_Ref = {{cascite|correct|CAS}}

| CAS_number = 104987-12-4

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = AUF4U5NSJK

| ATC_prefix = none

| ATC_suffix =

| PubChem = 5282071

| DrugBank_Ref = {{drugbankcite|correct|drugbank}}

| DrugBank =

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 4445297

| ChEBI_Ref = {{ebicite|changed|EBI}}

| ChEBI = 29582

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 8597

| C=43 | H=69 | N=1 | O=12

| smiles = O=C3C(=O)N1CCCC[C@H]1C(=O)O[C@H](C(=C/[C@@H]2CC[C@@H](O)[C@H](OC)C2)/C)[C@H](C)[C@@H](O)CC(=O)[C@@H](/C=C(\C[C@@H](C[C@H](OC)[C@H]4O[C@]3(O)[C@H](C)C[C@@H]4OC)C)C)CC

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C43H69NO12/c1-10-30-18-24(2)17-25(3)19-36(53-8)39-37(54-9)21-27(5)43(51,56-39)40(48)41(49)44-16-12-11-13-31(44)42(50)55-38(28(6)33(46)23-34(30)47)26(4)20-29-14-15-32(45)35(22-29)52-7/h18,20,25,27-33,35-39,45-46,51H,10-17,19,21-23H2,1-9H3/b24-18+,26-20+/t25-,27+,28+,29-,30+,31-,32+,33-,35+,36-,37-,38+,39+,43+/m0/s1

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = ZDQSOHOQTUFQEM-NURRSENYSA-N

| synonyms = 17-ethyl-1,14-dihydroxy-12-[2-(4-hydroxy-3-methoxy-cyclohexyl)-1-methyl-vinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-aza-tricyclo[22.3.1.04,9]octacos-18-ene-2,3,10,16-tetraone

}}

Ascomycin, also called Immunomycin, FR-900520, FK520, is an ethyl analog of tacrolimus (FK506) with strong immunosuppressant properties. It has been researched for the treatment of autoimmune diseases and skin diseases, and to prevent rejection after an organ transplant.{{cite journal | vauthors = Andexer JN, Kendrew SG, Nur-e-Alam M, Lazos O, Foster TA, Zimmermann AS, Warneck TD, Suthar D, Coates NJ, Koehn FE, Skotnicki JS, Carter GT, Gregory MA, Martin CJ, Moss SJ, Leadlay PF, Wilkinson B | display-authors = 6 | title = Biosynthesis of the immunosuppressants FK506, FK520, and rapamycin involves a previously undescribed family of enzymes acting on chorismate | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 108 | issue = 12 | pages = 4776–4781 | date = March 2011 | pmid = 21383123 | pmc = 3064383 | doi = 10.1073/pnas.1015773108 | doi-access = free | bibcode = 2011PNAS..108.4776A }}

Ascomycin acts by binding to immunophilins, especially macrophilin-12. It appears that Ascomycin inhibits the production of Th1 (interferon- and IL-2) and Th2 (IL-4 and IL-10) cytokines. Additionally, ascomycin preferentially inhibits the activation of mast cells, an important cellular component of the atopic response. Ascomycin produces a more selective immunomodulatory effect in that it inhibits the elicitation phase of allergic contact dermatitis but does not impair the primary immune response when administered systemically.{{cite journal | vauthors = Paul C, Graeber M, Stuetz A | title = Ascomycins: promising agents for the treatment of inflammatory skin diseases | journal = Expert Opinion on Investigational Drugs | volume = 9 | issue = 1 | pages = 69–77 | date = January 2000 | pmid = 11060661 | doi = 10.1517/13543784.9.1.69 | s2cid = 19730971 }}

Ascomycin is produced by the fermentation of certain strains of Streptomyces hygroscopicus.{{cite journal | vauthors = Yu Z, Lv H, Wu Y, Wei T, Yang S, Ju D, Chen S | title = Enhancement of FK520 production in Streptomyces hygroscopicus by combining traditional mutagenesis with metabolic engineering | journal = Applied Microbiology and Biotechnology | volume = 103 | issue = 23–24 | pages = 9593–9606 | date = December 2019 | pmid = 31713669 | doi = 10.1007/s00253-019-10192-8 | s2cid = 207955563 }}