Biomedical subjects
Publications and source records attributed to M Kelly-Borges.
A new tetramic acid glycoside, aurantoside C (3), was isolated from the sponge Homophymia conferta and the structure was determined by detailed 1D and 2D NMR analysis of the natural product and a hexaacetate derivative.
Chemical investigation of the sponge Spongia matamata collected in Yap, Micronesia, has resulted in the isolation of six new spongian diterpenoids, 2-7, along with the known compound, spongia-13(16), 14-dien-19-oic acid (1). The structures were determined by spectroscopic methods.
Bioassay-guided isolation of serine protease inhibitors from a marine sponge, Coscinoderma mathewsi, has yielded 1-methylherbipoline salts of halisulfate-1 and of suvanine. Structures of these compounds were identified by spectroscopic analyses and literature data. Antithrombin and antitrypsin activity was determined.
Four new imidazole alkaloids, 2-5, along with the known isonaamidine B (1) were isolated from a Pacific sponge, Leucetta cf. chagosensis, collected from Yap, Federated States of Micronesia. Among these, 4 and 5 are zinc complexes derived from isonaamidine B and isonaamidine D. The structures of the new compounds were elucidated from spectral data. Isonaamidine D (3) showed weakly antifungal activity against Aspergillus niger with MIC = 100 micrograms/mL.
Two new diterpenes possessing a 9-methyladeninium substituent, agelasines H (5) and I (6), along with five related known ones, 1-4 and 7, were isolated from a sponge, Agelas sp. The structures of the new compounds were determined from spectral data. Compounds 2-4, 6, and 7 exhibited varying degrees of antimicrobial activity.
A novel lysine derivative, 1, has been isolated from the marine sponge Axinyssa terpnis, in addition to 4alpha-isocyanogorgon-11-ene and related compounds (2-4). From the marine sponge Axinella carteri, the new 3-bromopyrrole carboxylic acid derivative, 5, was obtained along with the known compounds aldisin (6) and 2-bromoaldisin (7). Both sponges were collected from Chuuk Atoll, Federated States of Micronesia. The compounds were characterized by spectroscopic and chemical methods.
Three indole alkaloids, dilemmaones A-C (1-3), were isolated from a mixture of sponges that was collected near Cape Town, South Africa. The structures of dilemmaones A-C (1-3) were elucidated by interpretation of spectroscopic data. The dilemma caused by faulty differentiation of similar specimens in the field is discussed in detail.
Twelve new polychlorinated diketopiperazines (7-18), along with six known ones (1-6) and a known sterol (19), were isolated from the sponge Dysidea chlorea, collected from Yap, Federated States of Micronesia. The structures of dysamides I-T (7-18) were elucidated by spectroscopic methods, and one (8) was confirmed by chemical conversion. The stereochemistry of the dysamides is discussed.
As the result of a structurally guided isolation to identify lead compounds for the treatment of opportunistic infections of AIDS, the dihydrochloride salt of a new symmetrical pyrrole dimer debromosceptrin (1), and two known pyrrole analogues (2 and 3) were isolated from the Caribbean sponge Agelas coniferacollected from Belize. The structure of debromosceptrin was identified by analysis of spectral data. 15N spectral data assignments were made for compounds 1-3. Compounds 2 and 3 showed marginal inhibition of Mycobacterium tuberculosis.
A new member of the psammaplysin family, psammaplysin F (6) has been isolated from an undescribed species of Aplysinella sponge, along with the four known psammaplysins A-C (1-3) and E (5). The structure of psammaplysin F was determined by spectral analysis.
24(R)-Methyl-5 alpha-cholest-7-enyl 3 beta-methoxymethyl ether (1), a new sterol ether, has been isolated from a deep-water marine sponge Scleritoderma sp. cf. paccardi. Compound 1 exhibited in vitro cytotoxicity against the cultured murine P-388 tumor cell line with an IC50 of 2.3 micrograms/mL. The isolation and structure elucidation of 1 by NMR spectroscopy is described.
Two new substituted pyrrolecarboxylic acids, makaluvic acids A (5) and B (6), were isolated from the sponge Zyzzya fuliginosus, which was collected in Chuuk Atoll, Federated States of Micronesia. The known alkaloids 3,7-dimethylisoguanine (1) and makaluvamines A (2), E (3), and K (4) were also isolated.
The previously described manzamine A [1] and the new 8-hydroxymanzamine A [2] were isolated from an undescribed sponge, Pachypellina sp. Both compounds exhibit moderate antitumor and anti-HSV-II activity.
Three new peroxylactones, plakortolides B [6], C [7], and D [8], and a new peroxy ester, epiplakinic acid E methyl ester [9], were isolated and characterized from a previously unstudied marine sponge, Plakinastrella onkodes. A mixture of steroidal peroxides was also found in this organism. Plakortolides B [6] and D [8], and epiplakinic acid E methyl ester [9], were evaluated for biological activity and found to show cytotoxicity against the A549 human lung carcinoma and P388 murine leukemia cell lines, and to effect adhesion in an assay employing the EL-4.IL-2 cell line, which correlates with signal transduction activity.
Hamacanthin A [1] and hamacanthin B [2] are two bioactive dihydropyrazinonediylbis(indole) alkaloids isolated from a new species of deep-water marine sponge, Hamacantha sp. The hamacanthins are growth inhibitors of Candida albicans and Cryptococcus neoformans. Isolation and structure elucidation of 1 and 2 by nmr spectroscopy are described.
Ophirapstanol trisulfate [1], a new steroid trisulfate related to sokotrasterol trisulfate was isolated from a deep water marine sponge Topsentia ophiraphidites. Compound 1 exhibited significant inhibition in the guanosine diphosphate/G-protein RAS exchange assay. The structure elucidation of 1 and ophirapstanol [2] by nmr spectroscopy is described.
Traditionally, lithistid sponges have been combined within one order linked by the common possession of an interlocking siliceous desma skeleton. However, molecular data, morphology, and paleontology confirm recent hypothesis of polyphyly for this enigmatic group of sponges. Parsimony and neighbor-joining analysis of partial 18S rDNA sequences derived from amplified genomic rDNA of lithistids and other demosponges suggest that tetracladinid and dicranocladinid lithistids are monophyletic and closely related to choristid demosponges. Rhizomorinid families, in contrast, are indicated as being polyphyletic, with a diversity of points of origin within the tetractinomorph and the ceractinomorph poriferan subclasses. These arrangements are discussed in light of several hypotheses of demosponge evolution.
A new bastadin 2 and the previously reported bastadins 5 [3], 7 [4], and 12 (formerly bastadin 9) [5] were isolated from the Verongid sponge Psammaplysilla purpurea collected in Pohnpei. Compound 2 is mildly cytotoxic against several cell lines and inhibits the enzymes topoisomerase II and dehydrofolate reductase.