Some visnagin derivatives and related compounds Part I

ABSTRACT

Visnagin-9-sulphonyl chloride [II] was prepared and reacted * with ammonium acetate to give the corresponding sulphonamide [IIIa] which was acetylated to IV. Interaction of II with hydrazine hydrate gave V which reacted with aldehydes and with sulphonyl chlorides to give VI and VII respectively. Oxidation of visnagin [I] with chromic acid gave VIII which reacted with hydrazine hydrate to give the hydrazone [IX]. Interaction of IX with aldehydes and with sulphonyl chlorides gave X and XI respectively. Cyclization of VIII with ethylacetoacetate furnished the alpha.-pyrono -gamma- chomone [XIII] which reacted with aldehydes to give XIV