Heterocyclic systems containing bridge head nitrogen atom: Reaction of 5-mercapto-4H-imidazo[4,5-e]-[2,1,3]benzothiadiazoles and 5,6-diamino[2,1,3]benzothiazole with 3-(2-bromoacetyl)coumarins

摘要

Condensation of 5-mercapto-4H-imidazo[4,5-e][2,1,3]benzothiadiazole (I) with various 3-(2-bromoacetyl)coumarins, followed by PPA cyclization of the intermediate ketones II, yielded 3-(2,8-dithia 1,3,5b, 9-tetraaza cyclopenta(b)-as-indacen-6-yl)chromen-2-ones III. Reaction of 5,6-diamino[2,1,3]benzothiadiazole with 3-(2-bromoacetyl)coumarin in anhydrous ethanol containing fused sodium acetate gave the corresponding 2-coumarinyl 3,4-dihydro-1,4-pyrazino[5,6-e][2,1,3]benzothiadiazoles IV.