Holothuria mexicana

A novel two carbon analog of 8, namely the 7-methyl-6(Z)-octadecenoic acid was recently identified in the holothurian Holothuria mexicana [27]. However, both Z and E stereoisomers were later shown to originate from the bacterium Vibrio alginolyticus [27]. Therefore, the real source of 7-methyl-6-octadecenoic acid is also bacterial. Both Z and E isomers of 7-methyl-6-octadecenoic acid were synthesized as shown in Fig. (9). In this short synthesis (little more than one step) a Wittig coupling of (6-carboxyhexyl)triphenylphosphonium bromide with 2-tridecanone readily afforded a 1 1 mixture of 7-methyl-6(Z)-octadecenoic... 

Carballeira, N.M., Cruz, C., and Sostre, A. (1996) Identification of the novel 7-methyl-6-octadecenoic acid in Holothuria mexicana. J. Nat. Prod., 59,1076-1078. 

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