Synthesis of novel coumarin derivatives bearing heterocyclic substituents for chemoprophylactic evaluation

ABSTRACT

A series of coumarin derivatives bearing heterocyclic substituents was synthesized. Bromination of the key compound 8-acetyl-7-hydroxy-4-methylcoumarin [I] under varied conditions gave the brominated derivatives II, III and IV, Conversions of III by several cyclocondensations gave the corresponding thiazole V, quinoxaline VI, quinoxalinone VIII and furanone IX derivatives. Also, methylation and cyclocondensation of the methylene-active acetyl groups of II with several aldehydes gave the corresponding pyridone various amines gave the corresponding amino side chains. Some of these newly synthesized products were studied for their chemoprophylatic effect on Schistosoma mansoni infected mice. Compound Xc a showed moderate effect