共查询到17条相似文献,搜索用时 137 毫秒
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本文以樟脑衍生物(-)-莰烷磺内酰胺(2)为原料,经N-烷酰基莰烷-2,10-磺内酚胺(3)与碘代烷的不对称烷基化反应,用二锂代乙基苯基砜取代磺内酰胺助剂以及铝汞还原性脱硫反应等三步合成(S)和(R)一切叶蚁警戒信息素(1),其光学纯度高达95%e.e以上。 相似文献
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(2S,3R)┐谷象虫聚集信息素的合成黄锦霞*李焰马兴泉陈祖兴徐章煌(湖北大学化学系武汉430062)关键词(2S,3R)-谷象虫聚集信息素,合成,不对称顺式醇醛缩合反应,N-莰烷-磺内酰胺1997-07-14收稿,1997-09-29修回湖北省自然... 相似文献
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Subsequent treatment of N-crotoyl-(1S,2R)-bornane-10,2-sultam with EtMgCl, recrystallization of the product and saponification, afforded R-(-)-3-methylpenthanoic acid which was used for acylation of (1R,2S)-bornane-10,2-sultam. The product was converted into N-[(2S,3R)-2-amino-3-methylpentanoyl]-(1R,2S)-bornane-10,2-sultam by hydroxyamination with 1-chloro-1-nitrosocyclohexane, followed by reduction of the hydroxylamine grouping. Saponification of the sultam imide provided (+)-alloisoleucine. 相似文献
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Four new pyrrolidine alkaloids, broussonetines R, S, T, and V and a new pyrroline alkaloid, broussonetine U were isolated from the branches of Broussonetia kazinoki SIEB. (Moraceae) in low yield. Broussonetines R, S and T were formulated as (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R)-1-hydroxy-3-[6-(4-hydroxybutyl)-cyclohexy-2-on-1(6)-enyllpropyl] pyrrolidine (1), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R,10S)-1,10,13-trihydroxytridecyl] pyrrolidine (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R,5S)-1,5, 13-trihydroxy-10-oxo-tridecyl] pyrrolidine (3). And broussonetines U and V were proposed to be (2S,3S,4S)-2-hydroxymethyl-3, 4-dihydroxy-5-(9-oxo-13-hydroxytridecyl)-5-pyrroline (4), (2R,3S,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)-9-oxo-13-hydroxy-3-tridecenyl] pyrrolidine (5), respectively, by spectroscopic and chemical methods. 相似文献
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Structural determination of two new sesquiterpenes biotransformed from germacrone by Mucor alternata
Jia N Xiao Chi M Xiu Lan X Hong Wei J Dean G 《Magnetic resonance in chemistry : MRC》2008,46(2):178-181
Eight transformed sesquiterpenes of germacrone by Mucor alternata were obtained. Their structures were characterized on the basis of spectral methods including 2D NMR. Among them, (1S, 4S, 5S, 10R)-isozedoarondiol (2) and (1R, 4S, 5S, 10R)-diepoxy-12-hydroxygermacrone (3) are new compounds. 相似文献
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The synthesis of isofagomine lactams (2-oxoisofagomines) corresponding to the biologically important hexoses is presented. The D-glucose/D-mannose analogue (3S,4R,5R)-3,4-dihydroxy-5-hydroxymethylpiperidin-2-one (9) was synthesised in 9 steps from D-arabinose, the D-galactose analogue (3S,4S,5R)-3,4-dihydroxy-5-hydroxymethylpiperidin-2-one (10) was synthesised in 11 steps from D-arabinose and the L-fucose analogue (3R,4R,5R)-3,4-dihydroxy-5-methylpiperidin-2-one (11) was synthesised in 12 steps from L-arabinose. The three lactams 9-11 were found to be glycosidase inhibitors with micro- to nanomolar inhibition constants. The lactam 10 showed slow onset inhibition of beta-galactosidase from A. Oryzae. The rate constants for this process were determined to be k(on) = 2.55 x 10(4) M-1 s-1 and k(off) = 1.7 x 10(-3) s-1. The activation energies and standard thermodynamic functions were also determined. 相似文献
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Two new sesquiterpenes, 1S*, 4R*, 5S*, 6R*, 7S*, 10S*-1(5), 6(7)-diepoxy-4-guaiol (1) and 1S*, 4S*, 5S*, 10R*-4,10-guaianediol (2) have been isolated from the ethyl acetate soluble portion of the soft coral Sinularia sp., and their stereostructure were determined by spectroscopic methods and by X-ray single crystal analysis. Both compounds showed antioxidant and cytotoxic activities. 相似文献
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Asymmetric Synthesis and Crystal Structure of (-)-N-[(3R)-3-Cyclohexyl]-3-phenylpropananoyl]bornane-10,2-sultam 总被引:1,自引:1,他引:0
The title compound (-)-N-[(3R)-3-cyclohexyl]-3-phenylpropananoyl]bornane-10,2sultam (C 25 H 35 NO 3 S,M r=429.60),a derivative of camphorsultam,crystallizes in the monoclinic space group P2 1 /c with a=10.3301(7),b=19.4040(13),c=11.8106(8),β=100.5580(10)°,V=2327.3(3) 3,Z=4,D c=1.226 g/cm 3,λ=0.71073,μ(MoKα)=0.165 mm-1 and F(000)=928.X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat form (Fig.1).The planes constructed by (C(4),C(5),C(6),C(7)) and (C(7),C(8),C(9),C(4)) form a dihedral angle of 69.5°.The C(1)-C(2)-C(3) plane forms dihedral angles to the aforementioned planes of 89.8(1) and 85.9(3)°,respectively.And molecules are linked via hydrogen bonding (C-H···N/O) interactions. 相似文献
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As the glycosyl constituents of Ficus pumila L. fruits (Moraceae), three new sesquiterpenoid glucosides, pumilasides A, B and C were isolated together with benzyl beta-D-glucopyranoside, (E)-2-methyl-2-butenyl beta-D-glucopyranoside and rutin. Their structures were characterized as (1S,4S,5R,6R,7S,10S)-1,4,6-trihydroxyeudesmane 6-O-beta-D-glucopyranoside, (1S,4S,5S,6R,7R,10S)-1,4-dihydroxymaaliane 1-O-beta-D-glucopyranoside and 10 alpha, 11-dihydroxycadin-4-ene 11-O-beta-D-glucopyranoside by spectral and chemical methods. 相似文献