ABSTRACT
A new class of Mannich bases 9-26, derivatives of 2-amino-1H-benzimidazole, were obtained in the condensation of Schiff bases 1-4 or 2-benzylaminobenzimidazoles 5-8 with selected secondary amines: morpholine, piperidine, N-methylpiperazine, N-phenylpiperazine, 1-(2-pyridyl)piperazine, 1(2-methoxyphenyl)piperazine, 1-(2-pyrimidinyl)piperazine and formaldehyde in ethanol. The pyrimido[1,2-albenzimidazole derivatives 27-29 have been synthesized in the reactions of Schiff base 2 with selected compounds containing active methylene group: acetylacetone, benzoylacetone and malononitrile. The structures 1-29 were confirmed by the results of elementary analysis and their IR, 1H- and 13C-NMR spectra. The products 1-29 are of interest for biological studies and can be substrates for further synthesis. All compounds were screened against the cells of MV4-11 human leukemia and then the most active of them 5, 7, 9-16, 24-26, 28, 29 were tested towards human T47D breast and A549 lung cancer cells as well as normal mouse fibroblasts (BALB/3T3). The most active compound against the cancer cell lines was 4-amino-3-cyano-2-(4-hydroxyphenylene)-1,2-dihydropyrimi-do[1,2-a]benzimidazole (29) (IC50 0.23 ± 0.05 µg/mL against MV4-11 cells) showing in parallel very low cytotoxicity towards mouse fibroblasts. Cisplatin was the control drug.
Subject(s)
Antineoplastic Agents/chemical synthesis , Benzimidazoles/chemical synthesis , Animals , Antineoplastic Agents/pharmacology , BALB 3T3 Cells , Benzimidazoles/chemistry , Benzimidazoles/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , MiceABSTRACT
Two series of 2-thioxoimidazo[4,5-b]pyridine derivatives have been synthesized from 2,3-diaminopyridine (1) and 5-halogenosubstituted-2,3-diaminopyridines 2, 3. Mannich bases 7 - 12 and 24 - 29, derivatives of 1-arylamino-6-halogeno-2-thioxoimidazo[4,5-b]pyridine were obtained with selected secondary amines: morpholine, piperidine, 2-methoxyphenylpiperazine, pyrimidyn-2-yl-piperazine and formaldehyde in ethanol. The structures 7 - 12 and 24 - 29 were confirmed by the results of elementary analysis and their IR, 1H-NMR and MS spectra. All given structures 7 - 12 have been optimized to get the most stable low energy conformers. Synthesized compounds were of interest for biological studies or can be substrates for further synthesis. The selected compounds 7 - 10, 12- 17, 22, 25, 27 - 29 were screened for their antiproliferative activity in vitro against human cancer and normal mouse fibroblast cell lines.
Subject(s)
Aminopyridines/chemistry , Aminopyridines/pharmacology , Cell Proliferation/drug effects , Pyridines/chemistry , Pyridines/pharmacology , Animals , BALB 3T3 Cells , Cell Line , Cell Line, Tumor , Humans , MCF-7 Cells , MiceABSTRACT
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.
