Colensolide A: a new nitrogenous bromophenol from the New Zealand marine red alga Osmundaria colensoi

A new nitrogenous bromophenol, colensolide A, is isolated from the New Zealand red alga Osmundaria colensoi together with the known bromophenol lanosol and four of its derivatives. In this study, a novel technique is employed to identify potentially new compounds in semi-purified mixtures containing a plethora of structurally similar, known metabolites, using NMR spectroscopy. The structure and relative configuration of colensolide A is determined using standard spectroscopic techniques. Several of the known bromophenols exhibit antibacterial activity and one shows moderate cytotoxicity.