Bromopyrrole Alkaloids from a Marine Sponge <i>Agelas</i> sp.

Abstract

Five new bromopyrrole alkaloids, 2-bromokeramadine (1), 2-bromo-9,10-dihydrokeramadine (2), tauroacidins C (3) and D (4), and mukanadin G (5), were isolated from an Okinawan marine sponge Agelas sp. The structures of 1-5 were elucidated on the basis of spectroscopic data and conformational analysis. Mukanadin G (5) has a tricyclic skeleton consisting of a fused tetrahydrobenzaminoimidazole and 2,5-dioxopyrrolidine moieties. Antimicrobial activities of 1-3, and 5 as well as three related known bromopyrrole alkaloids, keramadine (6), tauroacidin A (7), and taurodispacamide A (8) were evaluated.Key words bromopyrrole alkaloid; marine sponge; Agelas sp.Marine sponges have been recognized as a rich source of bioactive metabolites with unique chemical structures.

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

“…Analyses of the NMR spectra implied that tauroacidins C-E (10-12) 21,23) were monomeric bromopyrrole alkaloids with an N-ethanesulfonic acid moiety (Fig. 5), and their structures were closely related to those of tauroacidin A, 24) previously isolated by our group from the Okinawan marine sponge Hymeniacidon sp.…”

“…25) Chiral HPLC analyses disclosed tauroacidins C-E (10-12) and mukanadin G (13) to be racemates. The structures of 14 and 15 were assigned as 2-bromo and 2-bromo-9,10-dihydro analogues 23) of keramadine, 26) respectively (Fig. 5).…”

Marine Pharmacology in 2014–2015: Marine Compounds with Antibacterial, Antidiabetic, Antifungal, Anti-Inflammatory, Antiprotozoal, Antituberculosis, Antiviral, and Anthelmintic Activities; Affecting the Immune and Nervous Systems, and Other Miscellaneous Mechanisms of Action

“…strain SNM55 [50]; a new glycolipid ieodoglucomide C (40) from the Korean marine-derived bacterium Bacillus licheniformis strain 09IDYM23 [51]; a new polycyclic tetramic acid macrolactam isoikarugamycin (41) from Equatorial Guinean Streptomyces zhaozhouensis strain CA-185989 [52]; a bromopyrrole alkaloid keramadine (42), isolated from the Okinawan marine sponge Agelas sp. [53]; "unprecedented" 9,11 secosterols with "the 2-ene-1,4-dione moiety" (43,44) from the Korean marine sponge Ircinia sp. [54,55]; two polybrominated diphenyl ethers (45,46) from the Papuan New Guinea marine sponge Lendenfeldia dendyi and the soft coral Sinularia dura [56]; a novel polyketide lindgomycin (47) from the Baltic sea and Arctic Lindgomycetaceae family marine fungal strains KF970 and LF327 [57]; a novel cycloheptadepsipeptide marfomycin D (48), isolated from a South China marine Streptomyces drozdowiczii SCSIO 10141 [58]; an glycohexadepsipeptide-polyketide mollemycin A (49) from an Australian marine-derived Streptomyces sp.…”

“…strain CMB-M0244 [59]; a novel laurene-type sesquiterpene neolaurene (50) from a Bornean marine alga Laurencia nangii [60]; a new polyketide and ambuic acid analogue penicyclone A (51), isolated form an extract from a deep-sea derived fungus Penicillium sp. F23-2 [61]; a new phenolic enamide (52), characterized from the Chinese marine alga Codium fragile-derived endophytic fungus Penicillium oxalicum strain EN-290 [62]; a novel meroterpenoid puupehenol (53), isolated from a Hawaiian sponge Dactylospongia sp. [63]; a new scalarane sesterpene phyllospongin E (54), isolated from the Egyptian Red sea sponge Phyllospongia lamellosa [64]; two new rare pyrane-based cembranoids sarcotrocheliol acetate (55) and sarcotrocheliol (56), isolated from the Red sea soft coral Sarcophyton trocheliophorum [65]; a novel depsidone-based analogue spiromastixone J (57), isolated from the fermentation broth of a deep-sea Spiromastix sp.…”

New bromopyrrole alkaloids from the marine sponge Agelas sp.

“…[21][22][23][24] The sponge Agelas sp. has proven to be a rich source of monomeric and dimeric bromopyrrole alkaloids, [25][26][27] diterpene alkaloids, 28,29 and glycosphingolipids. 30 In our search for structurally unique and bioactive alkaloids from marine sponges collected off the Xisha Islands in the South China Sea, we have identified a series of monomeric bromopyrrole alkaloids and diterpene alkaloids from the genus Agelas, 31,32 but not the dimeric bromopyrrole alkaloids.…”