丙二腈与3-硫代氨基甲酰基色酮的反应伴有重排,导致形成2,5-二氢-1 H-色胺[2,3 - b ]吡啶-3-甲腈或2-亚氨基-5-氧代-1 -苯基-2,5-二氢-1 H-铬[2,3 - b ]吡啶-3-碳硫酰胺,具体取决于硫代氨基甲酰基部分中取代基的性质。该反应与丙二腈与3-氨基甲酰基色酮的反应截然不同,后者产生香豆素-吡啶。
Mechanism of unusual formation of 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones and 4-oxo-4H-chromene-3-carbothioic acid N-phenylamides and their antimicrobial evaluation
摘要:
6/6,7-Substituted 3-formylchromones (9a-e) react with 2 equivalents of 2-phenyl-4-dimethylamino-1-thia-3-azabuta-1,3-diene (10) or thiobenzamide (11) in refluxing toluene to furnish novel substituted 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones (12a-e). However, reactions of substituted 2-anilino-3-formylchromones (15a-d) with thiobenzamide (11, 2 equivalents) in refluxing xylene furnish 4-oxo-4H-chromene-3-carbothioic acid N-phenylamide (17a-d) in high yields. A mechanistic rationalization of the conversion of 2-anilino-3-formylchromones (15a-d) to N-phenylamides (17a-d), and 3-formylchromones (9a-e) to the corresponding thioaldehydes, is proffered. All the compounds (12a-e, 17a-d) display very high antifungal and antibacterial activities against a number of strains. Dithiazole 12d exhibits a very high antifungal activity (MIC 5 mu g/ml) against Geotrichum candidum, better than fluconazole (MIC 09 mu g/ml) and also possesses good antibacterial activity (MIC 52 mu g/ml) against Shigella flexneri. (C) 2009 Elsevier Masson SAS. All rights reserved.
6/6,7-Substituted-3-formylchromones (8a-g) were reacted with 2 equivalents thiobenzamide (9) in refluxing toluene to furnish substituted -3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones (10a-g) in high yields. Similarly, when substituted-2-anilino-3-formylchromones (8a-d) were reacted with thiobenzamide (9, 2 equivalents) in refluxing xylene, 4-oxo-4H-chromene-3-carbothioic acid N-phenylamides (11a-d) were obtained in high yields. All the compounds (10a-g) and (11a-d) display significant cytotoxic activity against a number of human cancer cell lines. Among these compounds 10e (IC50 = 10 mu M), 10b (IC50 = 14.6 mu M) and 10a (IC50 = 10.5 mu M) showed maximum cytotoxic activity on neuroblastoma. Also, the compound 10c (IC50 = 10.5 mu M) showed maximum cytotoxic activity on ovarian cancer cell line. (C) 2009 Elsevier Masson SAS. All rights reserved.