| abstract |
FIELD: organic chemistry, natural compounds. n SUBSTANCE: invention describes derivatives of betulin of the general formula (I): , n wherein R 1 and R 2 mean similar or different groups and mean in common independently -SO 2 (OH) and their salts; -P(O)(OH) 2 and their salts; -CH 2 COOH and their salts wherein R 3 means -C(CH 3 )(=CH 2 ), -CH(CH 3 ) 2 , n n n n that are used as inhibitors of complement. Compounds of the formula (I) elicit higher activity and they are obtained from available triterpene betulin isolating from birch bark. n EFFECT: valuable properties of betulin derivatives. n 2 cl, 5 tbl, 8 ex |