The syntheses of the marine metabolites 3-bromoverongiaquinol and 5-monobromocavernicolin

Abstract

Recebido em 5/5/10; aceito em 27/6/10; publicado na web em 18/10/10 An efficient synthesis of the marine metabolite 3-bromoverongiaquinol (1) and the first total synthesis of 5-monobromocavernicolin (2), both isolated from the marine sponge Aplysina cavernicola, have been described based on the 1,2 addition of the lithium enolate of N,O-bistrimethylsilylacetamide (BSA, 4) to 1,4-benzoquinone (3). Bromination and purification of the crude product on silica gel chromatography provided 3-bromoverongiaquinol (1) in 50% overall yield. Under alkaline conditions, the crude product of the bromination reaction was converted to 5-monobromocavernicolin (2) in 20% yield which was also obtained in 13% yield (25% yield based on recovered starting material) from 3-bromoverongiaquinol (1).

Marine natural products

“…554 A racemic synthesis of 5-monobromocavernicolin (Aplysina cavernicola) 555 has been achieved. 556 DBU 501 has been reported for the first time from a natural source, the sponge Niphates digitalis (Boca de Calderas, Cuba). 557 Investigation of Haliclona tulearensis (Salary Bay, Madagascar) resulted in the isolation of haliclorensins B 502 and C 503.…”

Natural Products from Marine Invertebrates and Microorganisms in Brazil between 2004 and 2017: Still the Challenges, More Rewards

“…55 The sponge Haliclona tubifera provided the known halisphingosine A (106, Figure 13) and the new halisphingosine B (107, Figure 13), long-chain sphingoid bases derivatives, which possess an uncommon L-threo configuration for this class of natural products. 56 Cyclic alkylpyridine oligomers ( Figure 13) haliotoxin (108) and amphitoxin (109) have been isolated from the marine sponge Amphimedon sp. and displayed antifungal activity against Aspergillus flavus, a storage contaminant fungus affecting for commercial agricultural products.…”