Novel betulinic acid derivatives a-ring-condensed to a heterocyclic group

摘要

The invention relates to novel betulinic acid derivatives of formula (I), wherein R is C (=CH) CH or CH(CH) ; R together with the adjacent carbonyl group forms a carboxylic acid, carboxylic acid ester or amide or substituted amide; R or R are hydrogen or aryl with the proviso that both are not independently hydrogen or alkyl or R and R are combined together to form an aryl ring optionally substituted with a group X, wherein X is selected from halogen, alkyl, cyano, nitro, alkoxy, amino or substituted amine; Y is N or O; and R is zero when Y is O, and R is hydrogen, alkyl or aryl alkyl when Y is N, useful for inhibition of tumor cancer cells. Formula (I)