Cryptotethya crypta

Spongoadenosine (Ara-A, Vira-A) Vidarabin, Vira-A Cryptotethya crypta Sponge Antiviral (herpes) Arabinoside 1972... 

Cimino, G., De Rosa, S., and De Stefano, S. (1984c) Antiviral agents from a gorgonian, Eunicella cavolini one previously found in the sponge Cryptotethya crypta. Experientia, 40, 339-340. 

In this connection it is important to note that the unusual arabinosyl derivatives of thymine and uracil (222 and 223), so far detected in only one sponge species, Cryptotethya crypta 18), have served as a model for the synthesis of D-arabinosylcytosine, which has potent anticancer activity it inhibits the growth of Sarcoma 180, Ehrlich carcinoma and L-1210 Leukemia in mice 63, 64, 124). However, human tests of this compound for antitumor activity have been disappointing 175). 

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