ABSTRACT
A novel series of esters 8-10 and hydrazones 4-6 was synthesized from 4-aryl-2-phenacylidene-1,3,4,5-tetrahydropyrido[2,3-b][1,4]diazepine (1-3). Subsequent treatment of hydrazone 4 with p-chlorbenzaldehyde furnished azine 7. Long-standing heating of ester 8 with hydrazine hydrate afforded 3-[1-(p-chlorophenylene)-2-(5-phenyl-1H-pyrazol-3-yl)-ethyl]-1,3-dihydroimidazo[4,5-b]pyridin-2-one (11). The structures of 4-6 and 8-10 were identified by the results of elemental analysis and their IR, 1H-NMR and MS spectra. Additionally, the structure of 11 was confirmed by X-ray diffraction method. Compounds 8-10 and 11 were examined for their antiproliferative activity in vitro against the cells of 5 human cancer cell lines, using SRB or MTT technique. Among tested compounds, only 11 revealed cytotoxic activity in vitro against all cell lines applied with ID50 (inhibitory dose 50%) values lower than 4 microg/mL, which is an international activity criterion for synthetic compounds. All compounds inhibit the proliferation of HL-60 human promyelocytic leukemia cell line.
Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Imidazoles/chemical synthesis , Imidazoles/pharmacology , Pyridines/chemical synthesis , Pyridines/pharmacology , Crystallography, X-Ray , HL-60 Cells , Hep G2 Cells , Humans , Inhibitory Concentration 50 , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Structure , Structure-Activity RelationshipABSTRACT
A novel series of Schiff bases 1-11, the derivatives of 2-aminobenzimidazole and substituted aromatic aldehydes, has been synthesised. Compounds 1-11 reduced by NaBH(4) formed 2-benzylaminobenzimidazoles 12-21. 2-(o-Bromobenzylamino)benzimidazole (15) acylated by cinnamoyl chloride gave 2-(o-bromobenzylamino)-1-cinnamoylbenzimidazole (22). Long heating of 15 and 19 with p-nitrocinnamoyl or cinnamoyl chloride led to the formation of pyrimido[1,2-a]benzimidazol-4-ones 23 and 24. The structures of 1-24 were identified by the results of elemental analysis and their IR, (1)H NMR and MS spectra. Among the compounds 1-24 evaluated for their antiproliferative activity in vitro, 16, 19, 20 and 22 exhibited cytotoxic activity against the cells of human cancer cell lines, namely SW707 (rectal), HCV29T (bladder), A549 (lung) and T47D (breast cancer).
