Pyrrolidinoöxazolidine alkaloids from two species of ladybird beetles.

Abstract

From the mixture of alkaloids obtained from adults of two species of ladybird beetles, Epilachna varivestis and Epilachna borealis, a novel bicyclic alkaloid, 5-(12'-aminotridecyl)pyrrolidinoöxazolidine [(5 alpha, 7 a beta)-hexahydro-alpha-methylpyrrolo[2,1-b]oxazole-5-dodecaneami ne] (2) was characterized on the basis of spectrometric and synthetic investigations. This new alkaloid is related structurally to a monocyclic congener 1-(2-hydroxyethyl)-2-(12'-aminotridecyl)pyrrolidine (1), previously characterized from E. varivestis. Two additional alkaloids (lower homologs of 1 and 2) from E. borealis were characterized as 5-(10'-aminoündecyl)pyrrolidinoöxazolidine [(5 alpha,-7 a beta)-hexahydro-alpha-methylpyrrolo[2,1-b]oxazole-5-decaneamine ] (7) and 1-(2-hydroxyethyl)-2-(10'-aminoündecyl)pyrrolidine (8), on the basis of their mass spectra.