Chemistry of Verongida Sponges. 10. Secondary Metabolite Composition of the Caribbean Sponge Verongula gigantea

Abstract

A detailed analysis of the secondary metabolites of the Caribbean sponge Verongula gigantea has been performed. A number of bromotyrosine derivatives, 1, 2, and 6-17, were identified, one of which (17) is a novel compound. Its structure was determined on the basis of spectroscopic evidence. Additionally, aureol (18) and 5, 6-dibromo-N,N-dimethyltryptamine (19) were isolated from one of the five analyzed specimens.

Chromone and Phenanthrene Alkaloids from Dennettia tripetala.

“…The AAЈBBЈ system resonated as a complex signal ought to the preferred anti conformation along the corresponding carbons bond. 11) In the HMQC spectrum, the protons resonanting at d 2.92 showed a heteronuclear connectivity with the signal at d 59.5 while the protons at d 3.39 showed HMQC with the carbon at d 30.2. The homonuclear correlation (COSY 45) beetwen d 9.08 (H-5) and d 7.81 (H-6) aided in establishing the location of the methoxy group in C-7 and the methylenedioxy group in C3-4 on the phenanthrene skeleton.…”

Metabólitos secundários das esponjas Aplysina fistularis e Dysidea sp. e atividade antituberculose da 11-cetofistularina-3

“…25 O ácido 6 e seu respectivo éster metílico 7 não foram anteriormente isolados de esponjas Verongida do Brasil, e sim das esponjas Verongula sp., 16 Pseudoceratina sp. 17 e Verongula gigantea 26 do Caribe. Todavia, o éster etílico de 6 foi por nós isolado de Aplysina sp.…”

“…24 Embora o nome sistemático IUPAC 7,9-dibromo-10-hidroxi-8-metoxi-1-oxa-2-azaspiro[4.5]deca-2,6,8-trieno-3-carboxílico possa ser utilizado para designar o composto 6, o grupo de Fattorusso não propôs outra designação para esta substância. 16,17,26 Desta forma, propomos aqui o nome ácido verongidoico para 6 e éster metílico do ácido verongidoico para 7. Tal designação se justifica pelo fato de o ácido 6 ser a unidade estrutural mais comumente encontrada em derivados da dibromotirosina isolados de esponjas marinhas da ordem Verongida.…”

Antiparasitic bromotyrosine derivatives from the Caribbean marine sponge Aiolochroia crassa

“…For this reason, bromotyrosine metabolites have been considered as potential chemotaxonomic markers of sponges of the order Verongida. 7 A wide range of biological activities have been reported for these compounds including antimicrobial, enzymatic, cytotoxic and antiparasitic activities. 8 A previous study on the sponge A. crassa led to the discovery of antimicrobial activity of its extracts, 9 and the isolation and identification of several bromotyrosine derivatives, namely:…”