SESQUITERPENE DERIVATIVES

摘要

This invention relates to a novel sesquiterpene derivative expressed by the general formula (I): (I) wherein R1 represents a hydrogen atom, a lower alkyl group or a lower alkanoyl group; R2 and R3, which may be the same or different, each represents a formyl group, a hydroxymethyl group, a hydroxyl group, a carboxyl group, a lower alkanoyloxymethyl group, or a group having the formula -CH=CR7R8 in which R7 and R8, which may be the same or different, each represents a hydrogen atom, a cyano group, a lower alkoxycarbonyl group or a carboxyl group, or R2 and R3 may combine and form a lactone ring of the formula in which R9 represents a hydrogen atom or a hydroxyl group; R4 and R6, which may be the same or different, each represents a hydroxyl group or a lower alkanoyloxy group; R5 represents a hydrogen atom; R4 and R5 may together form an oxo group; and R4 and R6 may combine to form a lower alkylidenedioxy group; and the pharmaceutically acceptable salts thereof, and processes for the preparation thereof. These compounds have an excellent inhibitory activity against the complement system of animals and antitumor activity. These derivatives have a low toxicity level and are useful as active ingredients in therapeutic compositions useful in the treatment of such conditions as autoimmuno diseases, nephritis, rheumatism, collagen diseases, allergic diseases and cancer, or as intermediates for producing such active ingredients. The combined low toxicity and high anticomplementary activity provides distinct advantages over the prior known compounds.