共查询到20条相似文献,搜索用时 109 毫秒
1.
JimGuiDAI MengZHANG MinYE WeiHuaZHU JiYuGUO XiaoTianLIANG 《中国化学快报》2003,14(8):804-806
14-Deacetoxy-13-oxo sinenxan A (1) was converted to 9α-hydroxy-13-oxo-2α, 5α,10β-triacetoxy-4(20),ll-taxadiene (2) and 10β-hydroxy-13-oxo-2α,5α,9α-triacetoxy- 4(20), ll-taxadiene (3) by Ginkgo cell suspension cultures in 45% and 15% yields, respectively. 相似文献
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A New Asterosaponin from the Starfish Culcita novaeguineae 总被引:1,自引:0,他引:1
HaiFengTANG YangHuaYI LingLI PengSUN DaZhengZHOU BaoShuLIU 《中国化学快报》2005,16(5):619-622
A new asterosaponin named novaeguinoside A, along with a known saponin, asteronyl pentaglycoside sulfate, was isolated from the starfish Culcita novaeguineae. The new compound was identitied to be sodium 6α-O-{β-D-fucopyranosyl-(1→2)-β-D-fucopyranosyl-(1→4)-[β-D-quinovopyranosyl-(1→2)]-β-D-xylopyranosyl-(1→3)-[β-D-quinovopyranosyl}-5α-pregn-9(11)-en-20-one-3β-yl-sulfate by extensive spectral analysis and chemical evidence. 相似文献
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A new Sequiterpenoid from Eupatorium adenophorum Spreng 总被引:1,自引:0,他引:1
A new sequiterpenoid compound 8aα-hydroxy-1-isopropyl-4,7-dimethyl-1,2,3,4,6,8a-hexahydro-naphthalene-2,6-dione(1),together with seven known compounds anti-HH-dimer-coumarin(2),(-)-5-exo-hydroxy-bomeol(3),O-hydroxyl cinnamic acid(4),9β-hydroxy-ageraphorone(5),10Hα-9-oxo-ageraphorone(6),10Hβ-9-oxo-ageraphorone(7)and 9-oxo-10,11-dehydroageraphorone 8,was isolated from the leaves of Eupatorium adenopho-rum Spreng.The structures were elucidated by IR,~1H and ~(13)C NMR,EIMS,HMBC and single-crystal X-ray spec-tral data. 相似文献
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QingAnZHENG ChongRenYANG 《中国化学快报》2003,14(12):1261-1264
Two new C-22 steroidal lactone glycosides, named dracaenoside A and B were isolated from the methanol extract of the fresh stem of Dracaena cochinchinensis. Their structures were established as (20S)3β,14α,16β-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-α-L-rhamnopyranosyl (1→2)[ α-L-rhamnopyranosyl (l→4)]-β-D-glucopyranoside and (20S)3β, 14α,16β-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-α-L-rhamnopyranosyl (1→2)[β-D-glucopyranosyl(1→3)]-β-D-glucopyranoside by means of 2D NMR spectral and chemical methods. It is the first time that steroidal lactone glycosides were isolated from the genus Dracaena. 相似文献
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A new triterpene and a saponin from Centella asiatica 总被引:1,自引:0,他引:1
Quan Lin Yu Hong Quan Duan Wen Yuan Gao Yoshihisa Takaishi 《中国化学快报》2007,18(1):62-64
A new triterpene and a saponin,named 2α,3β,23-trihydroxyurs-20-en-28-oic acid(1)and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester(2),have been isolated from the aerial part of Centella asiatica.Their structures were elucidated by spectral methods,including 2D-NMR spectra. 相似文献
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<正>A new 5α-adynerin-type cardenolide,named funingenoside U(1),together with its aglycone,(17R)-3β-hydroxy-4β-acetoxy-8, 14β-epoxy-5α-card-20(22)-enolide,was isolated from the roots of Parepigynumfuningense.Their structures were established on the basis of spectral(MS,1D and 2D NMR) measurements and chemical evidences. 相似文献
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A new polyhydroxysteroidal glycoside,(20R,24R)-16-O-(4-O-methyl-2-acetamido-2-deoxy-β-D-galactopyranosyl)-24-ethyl- 5α-cholest-8(14)-en-3β,6β,7β,16α-tetrol(anthenoside A,1),was isolated from the starfish Anthenea chinensis.Its structure was elucidated by extensive spectral analysis and chemical evidences.1 exhibited significant cytotoxicity against human tumor K-562, BEL-7402 and U87MG cells. 相似文献
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Two new guaianolide-type sesquiterpenoids,4β,9β-dihydroxy-1α,5α-H-guaia-6,10(14)-dien(1) and 4β,9β,10α-trihydroxy-1α,5α-H-guaia-6-en(2),along with four known sesquiterpenoids(3a,3b,4 and 5),were isolated from Kadsura interior.Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR and HR-MS techniques.Compounds 3a and 3b were obtained as a pair of enantiomers,and their structure and absolute configuration were established from their extensive NMR spectra and by single-crystal X-ray analysis. 相似文献
9.
从红豆杉(taxus chinensis)枝叶中分到五个微量紫杉烷类二萜, 其中四个为新二萜, 分别为: 1β, 5α, 13α-trihydroxy-9α,10β-diacetate-2α-benzoatetaxa-4(20), 11-diene(1), 1β,13α-dihydroxy-9α,10β-diacetate-2α-benzoate-5α-cinnamatetaxa-4(20), 11-diene(2), 1β,5α-dihydroxy-9α,10β,13α-triacetate-2α-benzoatetaxa-4(20), 11-diene(3)和1β,2α,5α,9α,10β,13α-hexahydroxytaxa-4(20), 11-diene(4), 另外一个为已知二萜19-hydroxybaccatin III(5)。 相似文献
10.
从红豆杉(taxus chinensis)枝叶中分到五个微量紫杉烷类二萜, 其中四个为新二萜, 分别为: 1β, 5α, 13α-trihydroxy-9α,10β-diacetate-2α-benzoatetaxa-4(20), 11-diene(1), 1β,13α-dihydroxy-9α,10β-diacetate-2α-benzoate-5α-cinnamatetaxa-4(20), 11-diene(2), 1β,5α-dihydroxy-9α,10β,13α-triacetate-2α-benzoatetaxa-4(20), 11-diene(3)和1β,2α,5α,9α,10β,13α-hexahydroxytaxa-4(20), 11-diene(4), 另外一个为已知二萜19-hydroxybaccatin III(5)。 相似文献
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In this paper, we report a total synthesis of a naturally occurring pyrrolo[2,3-d]pyrimidine nucleoside, mycalisine A. Our synthetic strategy uses D-xylose as the startingmaterial and Vorbrüggen glycosylation as the key step. Mycalisine A was synthesized in 11 steps with a 15% overall yield. 相似文献
15.
Joseph J. Romano 《Tetrahedron letters》2005,46(13):2323-2326
Advanced C-prenylated intermediates for three aromatase inhibitors, including morachalcone A, can be synthesized through a Claisen-Schmidt condensation followed by Florisil®-catalyzed [1,3]-sigmatropic rearrangement of a prenyl phenyl ether. 相似文献
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We achieved the total synthesis of the histone deacetylase inhibitor spiruchostatin A, as the prelude to the preparation of a combinatorial library of its analogues. Two key reactions were an asymmetric acetate aldol reaction using a Zr-enolate and macrolactonization using the Shiina method. 相似文献
17.
The preparation of two new synthons, 2,5- and 2,6-dibromotryptophan esters, and their use in diastereoselective intramolecular N-acyliminium ion spirocyclization methodology for the rapid construction of spirotryprostatin A and analogues are described. 相似文献
18.
Francisco A. Macías David Chinchilla Jose M.G. Molinillo Frank R. Fronczek Kozo Shishido 《Tetrahedron》2008,64(23):5502-5508
Both epimers of Heliannuol A, first heliannane reported in the literature, isolated from Heliannthus annuus, have been prepared individually in a stereoselective route using a ring closing metathesis (RCM) as a key step to obtain the eight-membered ring. Very good overall yield was obtained in both cases. 相似文献
19.
A total synthesis of phomactin A (1) based on a Cr(II)/Ni(II) macrocyclisation from the aldehyde vinyl iodide 11, leading to 12, followed by elaboration of the epoxyketone 16, which then undergoes spontaneous pyran-hemiacetal formation on deprotection, is described. 相似文献