Anti-cryptococcal and nitric oxide synthase inhibitory imidazole alkaloidsfrom the calcareous sponge Leucetta cf chagosensis

Antifungal imidazole alkaloids were isolated from the Egyptian Red Sea spon ge Leucetta cf chagosensis using HPLC. These compounds were the previously reported naamidine A, B, D and G and the unreported symmetric imidazole alk aloid naamine D. Naamine D possesses moderate antifungal and nitric oxide s ynthase inhibitory activity. The structure of naamine D was determined usin g 1D and 2D NMR experiments including H-1-N-15 HMBC and high resolution mas s spectrometry. (C) 2000 Elsevier Science Ltd. All rights reserved.