Chemical investigation of the octocoral Briareum stechei, collected in the Ie Island, Okinawa,Japan, resulted in the isolation of a new briarane-type diterpenoid, briastecholide A (1), as wellas the previously reported metabolites, solenolide C (2) and briarenolide S (3). The structures ofbriaranes 1–3 were characterized through spectroscopic analysis, and the absolute configuration of2 was corroborated by a single-crystal X-ray diffraction analysis. Briarane 3 exhibited bioactivityagainst the protein expression of inducible nitric oxide synthase (iNOS).
