共查询到19条相似文献,搜索用时 84 毫秒
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(S)-3-hydroxy-tetrahydrofuran was synthesized from L-malic acid by esterification,reduction,cyclization.The chemical structures of the target compound was identified by element analysis,IR,NMR andMS spectra.The total yield and the purity of the product were 41% and 99.2%,the optical purity was 95.8%.This optimal synthetic procedure with lower cost and mild reaction conditions be worthy to have a further pilot manufacture. 相似文献
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以L-脯氨酰胺为起始原料,经氯乙酰氯酰化及三聚氰氯脱水一锅法制得(S)-N-氯乙酰基-2-氰基吡咯烷(4); 4与3-氨基-1-金刚烷醇经亲核取代反应合成了维格列汀,总收率75%,其结构经1H NMR和MS(ESI)确证。 相似文献
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1-苄氧羰基-3-叔丁氧羰酰氨基氮杂环丁烷的合成工艺改进 总被引:1,自引:0,他引:1
以苄胺和环氧氯丙烷为原料,经开环、关环、取代、还原、脱苄等反应合成了1-苄氧羰基-3-叔丁氧羰酰氨基氮杂环丁烷,总收率22.9%.其结构经1H NMR,13C NMR和MS表征. 相似文献
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Optically active (+)-(S)-5-sec-butyl- and (-)-(S)-3-sec-butyl-2(1H)-pyridinone are synthesized and the relationship between optical activity and minimum optical purity of the latter is determined. 相似文献
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A short synthesis of the enantiomer of the polyacetylenic natural product siphonodiol is described. The synthesis is based on the strategy of taking advantage of the hidden symmetry of the target molecule and minimizing the use of protecting groups, thereby reducing the total number of steps and increasing the overall efficiency. 相似文献
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R. Ya. Kharisov R. R. Gazetdinov G. Yu. Ishmuratov G. A. Tolstikov 《Chemistry of Natural Compounds》2001,37(2):140-142
The versatile chiral synthon methyl (R)-5,5-dimethoxy-3-methylpentanoate has been prepared for the first time via ozonolytic decyclization of (R)-4-menthenone, which is available from L-(-)-menthol. The optically pure juvenoid (S)-(+)-hydroprene can be prepared from the synthon 相似文献
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(+)-(1S,2S,5R)-8-联苯薄荷醇的合成 总被引:4,自引:0,他引:4
以(R)-( )-pu legone为起始原料,经1,4-加成,还原两步反应合成了手性辅助试剂( )-(1S,2S,5R)-8-联苯薄荷醇及其差向异构体(-)-(1R,2S,5R)-8-联苯薄荷醇,总产率95%。其结构经1H NMR,13C NMR,IR,MS和X-射线衍射仪表征。 相似文献
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A stereospecific requirement for hallucinogenesis applies to certain molecules containing an asymmetric center. Thus, only the R-isomers of substituted phenylisopropylamines and lysergic acid diethylamide are psychotomimetic. The enantiomers of a minor hallucinogen, S(+)- and R(-)-3-(2-aminopropyl)indole (α-methyltryptamine) ( 6a and 6b ) were synthesized via a 5-step manipulation from D - and L -tryptophan ethyl ester hydrochloride, respectively. Optical purity of these two isomers was determined by pmr spectroscopy of their complexes with a europium chiral shift reagent using the indole C2 H signal. 相似文献