:Iminocoumarin

Iminocoumarins are a group of chemicals consisting of a coumarin with an attached imine group.

Many derivatives of 2-iminocoumarin are applied as luminescence indicators,Nikolov, P.; Tyutyulkov, N.; Dryanska, V. Zeitschrift für Naturforschung. 1987, 42 (9), 987-993 laser dyes,{{cite journal | last=Asimov | first=M.M. | last2=Nikitchenko | first2=V.M. | last3=Novikov | first3=A.I. | last4=Rubinov | first4=A.N. | last5=Bor | first5=Zs. | last6=Gaty | first6=L. | title=New high-efficiency biscoumarin laser dyes | journal=Chemical Physics Letters | publisher=Elsevier BV | volume=149 | issue=2 | year=1988 | issn=0009-2614 | doi=10.1016/0009-2614(88)87210-5 | pages=140–144}}{{cite journal | last=Liepouri | first=F. | last2=Foukaraki | first2=E. | last3=Deligeorgiev | first3=T.G. | last4=Katerinopoulos | first4=H.E. | title=Iminocoumarin-based low affinity fluorescent Ca2+ indicators excited with visible light | journal=Cell Calcium | publisher=Elsevier BV | volume=30 | issue=5 | year=2001 | issn=0143-4160 | doi=10.1054/ceca.2001.0240 | pages=331–335}}Krimova A. I.; Petuchov V. A.; Popov M.B. Quant. Electronica (Moscow) 1985, 12 (10), 2163-2166 also they are known as biologically active compounds.{{cite journal | last=Bylov | first=Igor E | last2=Vasylyev | first2=Maksym V | last3=Bilokin | first3=Yaroslav V | title=Synthesis and anti-inflammatory activity of N-substituted 2-oxo-2H-1-benzopyran-3-carboxamides and their 2-iminoanalogues | journal=European Journal of Medicinal Chemistry | publisher=Elsevier BV | volume=34 | issue=11 | year=1999 | issn=0223-5234 | doi=10.1016/s0223-5234(99)00119-1 | pages=997–1001}}{{cite journal | last=Huang | first=Chi-Kuang | last2=Wu | first2=Feng-Ying | last3=Ai | first3=You-Xi | title=Polyhydroxylated 3-(N-phenyl) carbamoyl-2-iminochromene derivatives as potent inhibitors of tyrosine kinase p60c-src | journal=Bioorganic & Medicinal Chemistry Letters | publisher=Elsevier BV | volume=5 | issue=20 | year=1995 | issn=0960-894X | doi=10.1016/0960-894x(95)00422-p | pages=2423–2428}}Hadfield, J. A.; Pavlidis, V. H.; Perry, P. J.; McGown, A. T. Anti-Cancer Drugs. 1999, 10 (6), 591-595 Furthermore, structural features of 2-iminopyrane cycle cause unusual reactivity of these compounds.{{cite journal | last=Zhuravel' | first=Irina O. | last2=Kovalenko | first2=Sergiy M. | last3=Ivachtchenko | first3=Alexandre V. | last4=Chernykh | first4=Valentin P. | last5=Shinkarenko | first5=Pavlo E. | title=Synthesis of substituted 3-(5-amino-[1,3,4]thiadiazol-2-yl)-2H-pyrano[2,3-c]pyridin-2-ones | journal=Journal of Heterocyclic Chemistry | publisher=Wiley | volume=41 | issue=4 | year=2004 | issn=0022-152X | doi=10.1002/jhet.5570410407 | pages=517–524}}O'Callaghan C.N. Proc. R. Ir. Acad. 1973, 73 (17), 291-297 Most of the reported transformations affect directly the iminopyrane cycle, and the iminogroup is the main target for nucleophilic and electrophilic attacks in many cases. However furthermore the iminogroup these compounds can contain other functional groups, which can participate in such interactions. Thus, vicinal arrangement of the imino and amide nucleophilic groups in 2-iminocoumarin-3-(thio)carboxoamides 4, 5 produces great opportunity to utilize these compounds as building blocks to construct different heterocyclic systems.

Iminocoumarins can be formed by a variation of the Knoevenagel condensation by reaction of salicylaldehyde with substituted acetonitriles.{{cite journal | last=O'Callaghan | first=Conor N. | title=Isomerisation of 2-aryl-4-oxo-2,3-dihydrobenzopyrano[2,3-d]pyrimidines to 2-aryl-4-hydroxy-5H-benzopyrano[2,3-d]pyrimidines | journal=Journal of the Chemical Society, Perkin Transactions 1 | publisher=Royal Society of Chemistry (RSC) | year=1980 | issn=0300-922X | doi=10.1039/p19800001335 | page=1335-1337}}