Carboline-containing Manzamine Alkaloids

Carboline-containing Manzamine Alkaloids 8.2.1.1 Manzamine A Type... 

Manzamine alkaloids can be isolated from marine sponges. They often contain /3-carboline. This group has a diverse range of bioactivities. It also has its own way of establishing its structures. An intramolecular Diels-Adler reaction for manzamines has been proposed. The a is bisdihydropyridine (derived probably from amonia), and the (3 is intramolecular cycloaddition in a pentacyclic... 

The motuporamines are considered as manzamine-related alkaloids owing to their structural relationship with manzamine C (57), the simplest alkaloid of this family of compounds. Baldwin and Whitehead have proposed a plausible biogenesis for these 3-alkylpiperidine alkaloids, suggesting that they could be formed from three basic building blocks ammonia, a C3 unit, and a Cio unit [54]. The motuporamines, which contain a spermidine-like side chain instead of the alkylated p-carboline substructure of manzamine C, appear to be biogenetically derived from the same precursors, ammonia, acrolein, and a long-chain dialdehyde involved in the Baldwin-Whitehead pathway (Scheme 9.2). 

ABSTRACT Marine sponges have frequently afforded a wide variety of alkaloids. Polycyclic amines (3-alkylpiperidine alkaloids) are secondary metabolites that are profusely found in Indo-Pacific sponges. These compounds contain complicated skeletons with several macrocyclic rings. One of the first members of these exclusively sponge-derived alkaloids is manzamine A, which was described independently by Riga in 1986 and by Nakamura in 1987. This compound possesses an unusual pentacyclic diamine fused ring joined to Cl of a )S-carboline moiety. 

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