A new spiro-sesquiterpene from the sponge Dysidea fragilis

A new spiro-sesquiterpene, spirofragilin (1), along with a known related sesquiterpene, dehydroherbadysidolide (2), have been isolated from the marine sponge Dysidea fragilis collected in the South China Sea. The structure of 1 was elucidated on the basis of detailed spectroscopic analysis.