Heteroaromatization with 4-phenyldiazenyl-1-naphthol. Part I: Synthesis of some new naphthopyrans and naphthopyranopyrimidines

Reaction of 4-phenyldiazenyl /or 4-(p-tolyldiazenyl)-1-naphthol (1) with various substituted α-cyanocinnamonitriles (2a-h) and ethyl α-cyanocinnamates (2i-p) afforded 2-amino-4-(aryl)-6-(phenyldiazenyl /or p-tolyldiazenyl)-4H-naphtho[1,2-b]pyrano-3-carbonitrile (3a-h) and ethyl 2-amino-4-(aryl)-6-(phenyldiazenyl /or p-tolyldiazenyl)-4H-naphtho[1,2-b]pyrano-3-carboxylate (3i-p). Reaction of compound 3a with Ac2O or PhCOCl and formic acid afforded N-acetylamino or N,N-dibenzoylamino and naphthopyranopyrimidine derivatives (4-8), respectively. The structures of these compounds were established on the basis of IR, UV, 1H NMR, 13C NMR, and MS data

Heteroaromatization with 4-phenyldiazenyl-1-naphthol. Part III: One-pot synthesis and DFT study of 4H-naphthopyran derivatives

A one pot three component reaction of 4-phenyldiazenyl-1-naphthol (1), p-chloro benzaldehyde (2) and malononitrile or ethyl cyanoacetate (3) in ethanol/piperidine under reflux afforded 2-amino-4-(p-chlorophenyl)-6-phenyldiazenyl-4H-naphtho[1,2-b]pyrano-3-carbonitrile (4a) and ethyl 2-amino-4-(p-chlorophenyl)-6-phenyldiazenyl-4H-naphtho[1,2-b]pyrano -3-carboxylate (4b). Structure of these compounds was established on the basis of IR, 1H NMR, 13C NMR, Mass and UV-Vis spectra. Molecular geometry of compounds 4a and b was obtained at B3LYP/6-31+G(d) level. Two tautomers and two conformers were geometrically optimized. The tautomers are separated by about 7.942 kcal/mol while rotational conformers are only separated by 0.511 kcal/mol. Molecular reactivity descriptors including global electrophilicity, hardness, softness and local condensed Fukui functions were computed and discussed. Frontier molecular orbitals (HOMO and LUMO) were also computed

Synthesis, reactions and biological evaluation of benzyltriazolophthalazine derivatives

A series of triazolophthalazine derivatives (4-22) were synthesized and characterized. The structures of the newly synthesized compounds were confirmed by spectral data. The newly synthesized compounds were also screened for their antimicrobial activity