摘要：

The structures of three new briaran based diterpenes are reported from the gorgonian coral Junceela gemmacea. Their structures were deduced on the basis of extensive one- and two-dimensional high-field n.m.r. experiments. The metabolites were (1R,2R,5Z,7R,8S,9R,10R,11R,14R,17S)-2,14-diacetoxy-8,17:11,20-bisepoxy-9-hydroxybriar-5-en-18-one (3), (1R,2R,5Z,7R,8S,9R,10R,11Z,14R,17S)-2,14-diacetoxy-8,17-epoxy-9-hydroxybriara-5,11-dien-18-one (4), and 1R,2R,5Z,7R,8S,9R,10R,12R,14R,17S)-2,14-diacetoxy-8,17-epoxy- 9,12-dihydroxybriara-5,11(20)-dien-18-one (5). The compounds are closely related to recently reported metabolites from Briareum species of soft corals.

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