Phyllidia varicosa

A novel series of marine isonitriles is represented by three related tricyclic compounds, 76-78. 9-Isocyanopupukeanane (76) was isolated chiefly from a Ciocalypta sp. after the nudibranch Phyllidia varicosa was observed feeding on the off-white sponge [15]. Most of the sponges which at first had been identified... 

In the early 1960s, the secretion of a shell-less, brightly colored Hawaiian mollusk, Phyllidia varicosa Lamarck, was investigated by a marine biologist [70]. It seemed fitting that our interest in marine toxins led to an examination of the chemical constituents. 

Nudibranchs of the family PhylUdiidae often contain isonitriles which are derived from their dietary sources (sponges) (ref. P. Karuso s review). The Hawaiian nudibranch Phyllidia varicosa and its sponge prey Cioclapta sp. were found to eontain 9-siocyanopupukeanane [87] (71,72). 

Pupukeanone. c,sH240, Mr 220.35. A fish toxic metabolite from the nudibranch Phyllidia varicosa with the isotwistane skeleton. The sponges Ciocalypta spp. contain isocyano and Phycopsis terpnis thiocya-nato derivatives of pupukeanone. 

According to Scheuer (88), pupukeanane (10), the defensive chemical secretion of the nudibranch Phyllidia varicosa, must be regarded as a kairomone as well as an allomone, since the mollusks obtain it through association with a sponge tentatively identified as Hymena-cion sp. on which the nudibranch feeds. 

SPECTRAL data IR, PMR, Mass Spec organism Phyllidia varicosa (Mollusca) and Hymeniacidon sp. (Porifera) reference 60... 

Hagadone, M.R., Burreson, B.J., Scheuer, P.J., Einer, J.S., and Clardy, J. (1979) Defense allomone of the nudribranch Phyllidia varicosa. Help. Chim. Acta, 62, 2484-2494. 

Vhyllidia varicosajHymeniacidon sp. Phyllidia varicosa Burreson et al. 1975 Hagadone et al. 1979... 

Phyllidia varicosa 2- and 9-lsocyano-pupukeanane Hymeniacidon sp. Adinolfi eto/., 1977 Hagadone et o/., 1979... 

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