Dictyoceratin-A and -B, Novel Antimicrobial Terpenoids from the Okinawan Marine Sponge [formula omitted] sp.

Abstract

Two new antimicrobial sesquiterpenoids, dictyoceratin-A ( 3a) and -B ( 4a) were isolated from the Okinawan marine sponge Hippospongia sp. along with known compounds, furospinulosin-1 ( 1) and ilimaquinone ( 2). The structures of dictyoceratin-A ( 3a) and -B ( 4a) were determined on the basis of spectral data and their absolute configurations were deduced to be antipodal to that of ilimaquinone ( 2) by comparing an ozonolysia product( 5) with that ( 6) derived from ilimaquinone ( 2).