SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SOME NOVEL 5-SUBSTITUTED AND 6-SUBSTITUTED FUROCOUMARINS

5-Hydroxybergapten 1a and 5-hydroxyisopimpinellin lb react with bromin e and hydrated aluminium nitrate to give 5-hydroxy-6-bromobergapten 2a , 5-hydroxy-6-bromoisopimpinellin 2b, 5-hydroxy-6-nitrobergapten 2c an d 5-hydroxy-6-nitroisopimpinellin 2d. While the reaction of la and Ib with ammonium acetate and sodium acetate yield 5-aminobergapten 3a, 5- aminoisopimpinellin 3b, 5-acetoxybergapten 3c and 5-acetoxyisopirnpin ellin 3d. The treatment of la and Ib with ethyl bromoacetate and allyl bromide affords 5-ethyl acetatoxybergapten 3i, 5-ethyl acetatoxyisopi mpinellin 3j, 5- allyloxybergapten 4a and 5-allyloxyisopimpinellin 4b. Also, 5- hydrazidobergapten 3g, 5-hydrazidoisopimpinellin 3h, 5-azido bergapten 3m and 5-azidoisopimpinellin 3n are prepared through 5-ethyl carboxy bergapten 3e, 5-ethylcarboxy isopimpinellin 3f, 5-acetanilido sulphonyloxy bergapten 3k and 5-acetanilido sulphonyloxy isopimpinelli n 3l. Claisen rearrangement of 4a-b afford 6-allyl-5-hydroxybergapten 5a and 6-allyl-5-hydroxyisopimpinellin 5b.