Pantherinine, a cytotoxic aromatic alkaloid, and 7-deazainosine from the ascidian Aplidium pantherinum.

A new cytotoxic aromatic alkaloid, pantherinine [1], and a mixture of nucleosides including 7-deazainosine [3], have been isolated from the ascidian Aplidium pantherinum collected at Stenhouse Bay, South Australia. The structures were determined primarily from 1H- and 13C-nmr data, especially one-bond and multiple-bond proton-carbon correlations. Although 7-deazainosine [3] has been known as a synthetic compound for several decades, this appears to be the first report of its isolation as a natural product.