A cyclized didemnimide alkaloid from the caribbean ascidian didemnumconchyliatum

J Nat Prod. 1999 Feb;62(2):389-91. doi: 10.1021/np980409q.

Abstract

A novel, cyclized alkaloid of the didemnimide class, 5, has been isolated from extracts of the Caribbean ascidian Didemnum conchyliatum. The structure of 5 was assigned using combined spectral methods that emphasized one- and two-dimensional NMR methods. The new alkaloid is the cyclization product of didemnimide A (1) formed via a C-2 indole condensation with the imidazole nitrogen.