Salvadenosine, a 5'-deoxy-5'-(methylthio) nucleoside from the Bahamian tunicate Didemnum sp.

Salvadenosine, (1) a rare 5'-deoxy-5'-(methylthio) nucleoside, was isolated from the deep-water Bahaman tunicate Didemnum sp. The structure was solved by integrated analysis of MS and 1D and 2D NMR data. We revise the structure of the known natural product, hamiguanosinol, which is a constitutional isomer of 1, to 5 by interpretation of the spectroscopic data and comparison with synthesized nucleosides.