Three new steroidal sulfate pentaglycosides (asterosaponins), goniopectenos
ides A-C (1-3), were isolated from the polar extract of the starfish Goniop
ecten demonstrans. The pentasaccharide moiety Linked to C-6 of 3 beta -sulf
ated steroidal aglycones, consists of D-xylose, D-fucose, D-quinovose, and
the unprecedented 3-O-methyl-D-quinovose. The three asterosaponins differ f
rom each other in the side chains. Their structures were elucidated by exte
nsive NMR experiments including H-1-H-1 (COSY, TOCSY, ROESY) and H-1-C-13 (
HMQC and HMBC) spectroscopy as well as chemical evidence. The isolated aste
rosaponins have been found to significantly inhibit the settlement of the b
iofouling marine brown macroalga Hincksia irregularis.