Chemical studies of british columbia nudibranchs

The chemical constituents of the skin extracts of several nudibranchs have been examined. Extracts of Archidoris montereyensis contain the diterpenoic acid glyceride 20, its two monoacetates 24 and 25, the drimane sesquiterpenoic acid glyceride 26, the monoacetate 28, the monocyclofarnesic acid glyceride 30 and the glyceryl ether 31. Glyceride 20 has also been isolated from extracts of Archidoris odhneri. The odoriferous principle of Amsodoris nobilis extracts was shown to be the degraded sesquiterpenoid 33. Polycera tricolor extracts contain triophamine (19) as their major constituent. ¹⁴C labelled mevalonic acid is incorporated into the diterpenoic add glyceride 20 and the sesquiterpenoic acid glyceride 26 by A. montereyensis, and into the famesic add glyceride 12 by A. odhneri. The drimenoic add glyceride 26 and the glyceryl ether 31 show antifeedant activity against the tide pool sculpin Oligocottus maculosus.