Search results for "Spongia"
showing 8 items of 8 documents
Synthesis of spongian diterpenes: (−)-spongian-16-oxo-17-al and (−)-acetyldendrillol-1
2001
Abstract An efficient diastereoselective synthesis of the spongian diterpenes (−)-spongian-16-oxo-17-al ( 1 ) and (−)-acetyldendrillol-1 ( 13 ) is described starting from (+)-podocarp-8(14)-13-one ( 6 ) via the ester-dialdehyde 11 as key intermediate. The absolute configuration at C-17 in synthetic compound 13 has conclusively been proved by NOE experiments.
Cytotoxic drimane meroterpenoids from the Indonesian marine sponge Dactylospongia elegans
2017
Abstract Chemical investigation of the methanol extract of an Indonesian marine sponge Dactylospongia elegans (family Thorectidae) afforded two undescribed drimane meroterpenoidal metabolites, dactylospongenones G and H (1 and 2) together with thirteen known compounds (3–15) including pelorol, 5-epi-ilimaquinone, 5-epi-smenospongine, 5-epi-smenospongidine, nakijiquinone D, smenospongine C, isospongiaquinone, isosmenospongine, nakijiquinones A-C, G and 5-epi-nakijiquinone Q. The structures of the new metabolites were unambiguously determined by 1D and 2D NMR spectroscopy and by HRESIMS. All isolated compounds were assessed for their antimicrobial, antitubercular and cytotoxic activities. Sev…
Diastereoselective synthesis of spongian diterpenes. Total synthesis of the furanoditerpene (−)-spongia-13(16),14-diene
1999
Abstract An effective diastereoselective synthesis of the marine-sponge metabolite (−)-spongia-13(16),14-diene 1 is achieved starting from S-(+)-carvone via a homochiral phenanthrenone as the key intermediate for the construction of the furan ring system. S-(+)-Carvone was transformed into the phenanthrenone 2a in six steps (53% overall yield), using an intramolecular Diels-Alder reaction as the key step. Conversion of the enone function in 2a into an epoxyaldehyde function followed by cyclisation and aromatisation in acid conditions completed the construction of ring D.
Strombine dehydrogenase in the demosponge Suberites domuncula: Characterization and kinetic properties of the enzyme crucial for anaerobic metabolism
2008
Previously, the cDNA and the respective gene for a presumed tauropine dehydrogenase (TaDH) from Suberites domuncula (GenBank accession nos. AM712888, AM712889) had been annotated. The conclusion that the sequences encode a TaDH had been inferred from the 68% identity with the TaDH protein from the marine demosponge Halichondria japonica. However, subsequent enzymatic assays shown here indicate that the presumed S. domuncula opine dehydrogenase is in fact a strombine dehydrogenase (StDH). The enzyme StDH is highly specific for glycine and is inhibited by an excess of the substrate pyruvate. Besides kinetic data, we report in this study also on the predicted tertiary and quaternary structure …
Sekundāro metabolītu izdalīšana no sūkļa Smenospongia aurea
2015
Darba mērķis bija jaunu sekundāro metabolītu izolēšana no sūkļa Smenospongia aurea un to ķīmiskās struktūras noteikšana. Tomēr, uzsākot darbu, nolēmām izdalīt oriģinālus, neribosomālus hibrīdu peptīdu/poliketīdu savienojumus – smenamīdu A, smenamīdu B, smenotiazolu A un smenotiazolu B –, kas jau iepriekš izdalīti no S. aurea sūkļa un kam noteikta augsta citotoksiska aktivitāte. Interesējošos savienojumus izdalījām no lipofīla sūkļa S. aurea ekstrakta, izmantojot augsti efektīvo šķidrumu hromatogrāfijas (AEŠH) metodi, to ķīmisko struktūru noteicām ar augstas izšķirtspējas masspektrometrijas (ESI/MS), 1H kodolu magnētiskās rezonanses (KMR) un 13C KMR metodēm, un iegūtos datus salīdzinājām ar …
CCDC 605711: Experimental Crystal Structure Determination
2006
Related Article: A.J.Blake, M.A.Gonzalez, M.J.Gil-Gimeno|2006|Acta Crystallogr.,Sect.C:Cryst.Struct.Commun.|62|o208|doi:10.1107/S0108270106006366
ChemInform Abstract: Diastereoselective Synthesis of Spongian Diterpenes. Total Synthesis of the Furanoditerpene (-)-Spongia-13(16),14-diene.
2010
Abstract An effective diastereoselective synthesis of the marine-sponge metabolite (−)-spongia-13(16),14-diene 1 is achieved starting from S-(+)-carvone via a homochiral phenanthrenone as the key intermediate for the construction of the furan ring system. S-(+)-Carvone was transformed into the phenanthrenone 2a in six steps (53% overall yield), using an intramolecular Diels-Alder reaction as the key step. Conversion of the enone function in 2a into an epoxyaldehyde function followed by cyclisation and aromatisation in acid conditions completed the construction of ring D.
Speciation of sponges in Baikal-Tuva region: an outline
2006
Lake Baikal is known for its high percentage of endemic fauna and flora. The most abundant sessile animal taxa in the littoral zone of Baikal are the photosymbiotic sponges. These endemic sponges are grouped to the family Lubomirskiidae and are separated, based on molecular data, from the cosmopolitan family Spongillidae Gray 1867. In the present review, recent data on the potential driving forces of the rapid speciation in Lake Baikal have been unified. Current data suggest that the genetic repertoire of the sponges was sufficiently large to cope with the major cold events, occurring 2.8–2.5 and 1.8–1.5 Ma. It is proposed that during those periods of climatic incisions founder populations …