Hodgsonal, a New Drimane Sesquiterpene from the Mantle of the Antarctic Nudibranch Bathydoris hodgsoni.

Abstract A new drimane sesquiterpene, hodgsonal ( 1 ), has been isolated from the mantle extract of the Antarctic opisthobranch mollusc Bathydoris hodgsoni . The structure of 1 , including the absolute stereochemistry, has been elucidated by spectroscopic and chemical methods. The localization of 1 in the mantle and the analogies with related drimane compounds may indicate a defensive role against predators.