Unusual conversion of substituted-3-formylchromones to 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones: a facile and efficient route to novel 1,2,4-dithiazoles
摘要:
Substituted 3 -formylchromones react with 2-phenyl-4-dimethylamino-1-thia-3-azabuta-1,3-diene(4) or thio-benzamide (7) by heating their toluene solution in a sealed tube to give novel substituted 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones (6a-e) in high yields. (c) 2007 Elsevier Ltd. All rights reserved.
Unusual conversion of substituted-3-formylchromones to 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones: a facile and efficient route to novel 1,2,4-dithiazoles
作者:Tilak Raj、M.P.S. Ishar、Vivek Gupta、Ajay Pal Singh Pannu、Priyanka Kanwal、Gurpinder Singh
DOI:10.1016/j.tetlet.2007.11.081
日期:2008.1
Substituted 3 -formylchromones react with 2-phenyl-4-dimethylamino-1-thia-3-azabuta-1,3-diene(4) or thio-benzamide (7) by heating their toluene solution in a sealed tube to give novel substituted 3-(5-phenyl-3H-[1,2,4]dithiazol-3-yl)chromen-4-ones (6a-e) in high yields. (c) 2007 Elsevier Ltd. All rights reserved.
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
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.
Cytotoxic activity of 3-(5-phenyl-3 H -[1,2,4]dithiazol-3-yl)chromen-4-ones and 4-oxo-4 H -chromene-3-carbothioic acid N -phenylamides
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.