New bromo-pyrrole derivatives from the sponge Agelas oroides

Abstract

The sponge Agelas oroides contains 4,5-dibromopyrrole-2-carboxylic acid (4), the corresponding nitrile and amide; oroidin contains an amide derived from (4) and a substituted 2-aminoimidazole.

Structure of debromo-carteramine A, a novel bromopyrrole alkaloid from the Mediterranean sponge Axinella verrucosa

“…[1][2][3][4][5][6][7] Historically, these compounds, which have been found only in the marine environment to date, have attracted the attention of natural product chemists because of their structural complexity. Today, the interest is sparked not only by the wide structural diversity, ranging from simple molecules like oroidin 8,9 to complex structures like palau'amine 10,11 and stylissadine A and B, 12 but also by their organic synthesis, 13 bio-synthesis, 14 and pharmacological activities. 6,7,15 Furthermore, these compounds have a chemo-ecological interest due to their role in chemically mediated interactions such as in the chemical defense against predators 16,17 and fouling organisms.…”

Chemotaxonomy of Agelas (Porifera: Demospongiae)

“…The methanol extract of the sponge yielded 0.1 g of Fr A, 1.7 g of Fr B, 5.5 g of Fr C and 3.2 g of Fr D. Fraction B (310 mg) was chromatographed on Sephadex LH-20 (MeOH), C, 8 reversed phase (MeOH-H~O 0/100 to 100/0) and silica gel (CHCI3-MeOH-NH 3 25% 10/3/1) successively. This yielded 28 (Nakamura et al, 1984c;Kobayashi et al, 1986b) and 16 (Forenza et al, 1971) identified on the basis of their spectral properties (IR, UV, 1H and ~3C NMR). Moreover, TLC of Fr B showed the presence of 29.…”

Bromopyrrole Alkaloids from Okinawan Marine Sponges <i>Agelas</i> spp.

“…4). Nagelamide W (9) (6) and Nagelamides U-W (7)(8)(9) might be biogenetically generated by the addition of guanidine to oroidin.…”

“…15) As part of that research project, bromopyrrole alkaloids in sponges Agelas spp. (SS-162, SS-307) were investigated, resulting in the isolation of 18 unique alkaloids including five dimeric bromopyrrole alkaloids (1-5), ten monomeric bromopyrrole alkaloids (6)(7)(8)(9)(10)(11)(12)(13)(14)(15), and three conjugates of monomeric bromopyrrole alkaloid and hydroxykynurenine (16)(17)(18). In this mini-review, we describe the isolation, structure elucidation, and antimicrobial activities of these alkaloids.…”

“…Representative bromopyrrole alkaloids, oroidin 8,9) and hymenidin, 10) are composed of an aminoimidazole moiety and a brominated pyrrole-amide moiety linked through a C 3 unit (Fig. 1).…”