α-and γ-Pyrone-poly·propionates from the mediterranean ascoglossan mollusc ercolania funerea

Abstract

Six polypropionic α- and γ-pyrones were isolated from the Stiligeridae ascoglossan mollusc Ercolania funerea . Their specific structures, elucidated by means of spectroscopic methods, are related to those of α- and γ-pyrones recently found in Polybranchioidea ascoglossans. Preliminary in vivo biosynthesis experiments conducted with ( 14C)-sodium propionate suggest that α- and γ-pyrones derive from an endogenous secondary metabolic pathway common to ascoglossan species belonging to the Polybranchioidea super-family.