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A new furanoterpene designated dehydrofurodendin and nine scalarane sesterterpenes of which four are new, were isolated from two different species of Madagascan sponges of the genus Lendenfeldia, both of which seem to be yet undescribed. The structure of the compounds was elucidated by interpretation of 1D and 2D NMR data. Dehydrofurodendin was found to be a potent inhibitor of HIV-1 RT. Several of the isolated scalaranes exhibited cyctotoxicity against several human tumor cells. 相似文献
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A. S. Antonov A. I. Kalinovskii V. A. Stonik E. V. Evtushenko G. B. Elyakov 《Russian Chemical Bulletin》1994,43(7):1265-1269
A new triterpenoid glycoside, (20S,22S,23R,24S)-3,22,23-trihydroxy-3-O-[O-(-D-glucuronopyranosyl)-(16)-(-D-glucopyranosyl)]-14-nor-24-methyllanost-8(9)-en-31-oic acid (ulososide A), has been isolated from the sponge Ulosa sp. and characterized.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1326–1329, July, 1994. 相似文献
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Margarida Costa Rogelio Fernández Marta Pérez Margrét Thorsteinsdottir 《Natural product research》2020,34(8):1053-1060
AbstractTwo new marine natural compounds, 3β-acetoxy-15-hydroxyspongia-12-en (1) and 3-methylspongia-3,12-dien-16-one (2), were isolated from the marine sponge Acanthodendrilla sp., collected in Pulau-Pulau. Compounds 1 and 2 represent new chemical entities of the known spongian diterpene family. Compound 1 is a new 3-acetoxyspongia and compound 2 presents an unreported rearranged 3-methylspongia-3-en. Their structures, including relative configurations, were fully elucidated based on 1D and 2D NMR analyses, as well as HRESTOFMS experiments. No significant bioactivities were found for these compounds. This work reports two new chemical structures, compounds 1 and 2, together with the first isolation of spongian diterpenes from Acanthodendrilla genus. 相似文献
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Mylene M UyShinji Ohta Mihoko YanaiEmi Ohta Toshifumi HirataSusumu Ikegami 《Tetrahedron》2003,59(6):731-736
Three new spirocyclic sesquiterpenes designated exiguamide (1), exicarbamate (2) and exigurin (3), together with (−)-10-epi-axisonitrile-3 (4), have been isolated from the marine sponge Geodia exigua. All four compounds possess the spiro[4.5]decene skeleton and their structures were determined on the basis of spectroscopic data. The structure of 1 was confirmed by X-ray crystallographic analysis and the absolute configuration was determined by applying the modified Mosher's method on its amine derivative. Exiguamide (1) inhibited cell fate specification during sea urchin embryogenesis at a minimum inhibitory concentration of 0.4 μM. 相似文献
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Christopher Cox Harald Wack Thomas Lectka 《Angewandte Chemie (International ed. in English)》1999,38(6):798-800
N-Protonated amides have been proposed as intermediates in several biologically important reactions, but they have yet to be identified spectroscopically. The first step toward this goal is now reported in the form of spectroscopic and crystallographic proof of a strong intramolecular hydrogen bond between a charged proton donor and an amide nitrogen atom in the “proton sponge” derivative 1 ; novel reactivity results from this interaction. TfO−=trifluoromethanesulfonate. 相似文献
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Theoretical calculations at the B3LYP/6-31G* level were carried out on a family of 1,8-diR-naphthalenes, which include the proton sponge (1,8-bisdimethylaminonaphthalene, R = NMe2) and other substituents (R = NH2, R = OH, R = CH3, R = F). Their basicity was compared with that of the corresponding monosubstituted benzenes. The dianion of 1,8-dihydroxynaphthalene should be a compound of extraordinary high basicity. The barriers to proton transfer, geometry, and density at the bond critical point of the hydrogen bond have been calculated and compared with experimental data when available. 相似文献
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This review highlights recently discovered antimalarial natural products from marine and freshwater sources described in the literature from 2006 to 2008. The structures as well as bioactivities of compounds against the malaria parasites such as Plasmodium falciparum are discussed, including, for example, agelasine, xestoquinone, alisiaquinone, crambescidin, venturamide, dragomabin, gragonamide, viridamide, salinosporamide, chaetoxanthone, nodulisporacid, tumonoic acid, girolline, oroidin, nostocarboline, aerucyclamide, and microcylamide 7806 and its revised structure. Synthetic derivatives of natural products are presented including plakortin, isoaaptamine, curcuphenol, pseudopyronine, manzamine, and nostocarboline. Consequences of these discoveries for the development of novel natural product agents against malaria are discussed. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 187–198; 2009: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.200900001 相似文献
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《Angewandte Chemie (International ed. in English)》2017,56(49):15520-15538
Low‐density macroporous sponges with densities less than 100 mg cm−3 are both a challenge and an opportunity for advanced chemistry and material science. The challenge lies in the precise preparation of the sponges with property combinations that lead to novel applications. Bottom‐up and top‐down chemical and engineering methods for the preparation of sponges are a major focus of this Review, with an emphasis on carbon and polymer materials. The light weight, sustainability, breathability, special wetting characteristics, large mass transfer, mechanical stability, and large pore volume are typical characteristics of sponges made of advanced materials and could lead to novel applications. Some selected sponge properties and potential applications are discussed. 相似文献