研究了1-丁基-3-甲基咪唑六氟磷酸盐[BMIM]PF6/缓冲液两相体系中,热带假丝酵母104细胞催化3,5-双三氟甲基苯乙酮不对称还原制备(S)-1-[3,5-双(三氟甲基)苯基]乙醇的反应过程。通过考察影响生物还原反应的主要因素,如离子液体浓度、辅助...研究了1-丁基-3-甲基咪唑六氟磷酸盐[BMIM]PF6/缓冲液两相体系中,热带假丝酵母104细胞催化3,5-双三氟甲基苯乙酮不对称还原制备(S)-1-[3,5-双(三氟甲基)苯基]乙醇的反应过程。通过考察影响生物还原反应的主要因素,如离子液体浓度、辅助底物种类和浓度、底物浓度、菌体浓度和转化时间等,发现上述因素对产率影响较大,但基本不影响产物手性醇的光学纯度。优化得到的较佳还原反应条件为:[BMIM]PF6体积分数5%,辅助底物为60 g L 1异丙醇,底物3,5-双三氟甲基苯乙酮浓度70 mmol L 1,菌体浓度350 g L 1,转化时间24 h。在优化条件下,产率达82.5%,产物(S)-1-[3,5-双(三氟甲基)苯基]乙醇的对映体过量值大于99.9%。与水相转化相比,采用[BMIM]PF6/缓冲液两相体系进行3,5-双三氟甲基苯乙酮的生物不对称还原可有效提高底物浓度和产率,且反应时间缩短了6 h。展开更多
[Objective]The study aimed to screen the starch-degrading bacterium in bagasse and carry on the identification of strains s2g5-1 and s3g4-8.[Method]By using a variety of selective media,varieties of starch degrading b...[Objective]The study aimed to screen the starch-degrading bacterium in bagasse and carry on the identification of strains s2g5-1 and s3g4-8.[Method]By using a variety of selective media,varieties of starch degrading bacterium were isolated from the sugar cane bagasse form different stages of natural fermentation,then,primary screening and secondary screening were performed.[Result] Starch-degrading strains s2g5-1 and s3g4-8 were screened,and they were identified as Bacillus amyloliquefaciens according to their morphological,physiological,biochemical and molecular characteristics.[Conclusion]The research provided theoretical basis for factory application of bagasse.展开更多
有机催化剂(S)-5-(吡咯烷-2-基)-1H-四唑为L-脯氨酸衍生物,可以高立体选择性的催化一些有机反应。报道了(S)-5-(吡咯烷-2-基)-1H-四唑的合成方法,以N-苄氧羰基-L-脯氨酸为原料,经过酰胺化反应、脱水反应、[3+2]环加成反应和氢化脱保护反...有机催化剂(S)-5-(吡咯烷-2-基)-1H-四唑为L-脯氨酸衍生物,可以高立体选择性的催化一些有机反应。报道了(S)-5-(吡咯烷-2-基)-1H-四唑的合成方法,以N-苄氧羰基-L-脯氨酸为原料,经过酰胺化反应、脱水反应、[3+2]环加成反应和氢化脱保护反应,并且最终产物以重结晶方法纯化,其结构经1 H NMR和13 C NMR表征。展开更多
文摘研究了1-丁基-3-甲基咪唑六氟磷酸盐[BMIM]PF6/缓冲液两相体系中,热带假丝酵母104细胞催化3,5-双三氟甲基苯乙酮不对称还原制备(S)-1-[3,5-双(三氟甲基)苯基]乙醇的反应过程。通过考察影响生物还原反应的主要因素,如离子液体浓度、辅助底物种类和浓度、底物浓度、菌体浓度和转化时间等,发现上述因素对产率影响较大,但基本不影响产物手性醇的光学纯度。优化得到的较佳还原反应条件为:[BMIM]PF6体积分数5%,辅助底物为60 g L 1异丙醇,底物3,5-双三氟甲基苯乙酮浓度70 mmol L 1,菌体浓度350 g L 1,转化时间24 h。在优化条件下,产率达82.5%,产物(S)-1-[3,5-双(三氟甲基)苯基]乙醇的对映体过量值大于99.9%。与水相转化相比,采用[BMIM]PF6/缓冲液两相体系进行3,5-双三氟甲基苯乙酮的生物不对称还原可有效提高底物浓度和产率,且反应时间缩短了6 h。
基金Supported by the Central Public-interest Scientific Institution Basal Research Fund(2008hzs1J021,2009hzs1J033)~~
文摘[Objective]The study aimed to screen the starch-degrading bacterium in bagasse and carry on the identification of strains s2g5-1 and s3g4-8.[Method]By using a variety of selective media,varieties of starch degrading bacterium were isolated from the sugar cane bagasse form different stages of natural fermentation,then,primary screening and secondary screening were performed.[Result] Starch-degrading strains s2g5-1 and s3g4-8 were screened,and they were identified as Bacillus amyloliquefaciens according to their morphological,physiological,biochemical and molecular characteristics.[Conclusion]The research provided theoretical basis for factory application of bagasse.
文摘有机催化剂(S)-5-(吡咯烷-2-基)-1H-四唑为L-脯氨酸衍生物,可以高立体选择性的催化一些有机反应。报道了(S)-5-(吡咯烷-2-基)-1H-四唑的合成方法,以N-苄氧羰基-L-脯氨酸为原料,经过酰胺化反应、脱水反应、[3+2]环加成反应和氢化脱保护反应,并且最终产物以重结晶方法纯化,其结构经1 H NMR和13 C NMR表征。
