Euplexaura erecta

A guinea pig ileum bioassay was used to detect and aid in the isolation of a smooth-muscle-contracting substance from the Japanese gorgonian coral Euplexaura erecta [108]. This process led to the isolation of prostaglandin F2a (17) from the MeOH extract of the coral. Its identification was based on comparison with authentic PGF2a and its methyl ester by TLC, and comparison with authentic methyl PGF2a trimethylsilyl ether by mass spectrometry. Because of the nature of the techniques employed, some aspects of the stereochemistry in this isolate of PGF2a remain uncertain. 

Fusetani, N., S. Matsunaga, and S. Konosu Bioactive Marine Metabolites. I. Isolation of Guaiazulene from the Gorgonian Euplexaura erecta. Experientia 37, 680 (1981). 

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