Asymmetric Trasformation of Symmetrical Epoxides to Allylic Alcohols by Lithium (<i>S</i>)-2-(<i>N</i>,<i>N</i>-Disubstituted aminomethyl)pyrrolidide
作者:Masatoshi Asami
DOI:10.1246/bcsj.63.721
日期:1990.3
Enantioselective deprotonation of symmetrical epoxides was studied by using chiral lithium amide, prepared from (S)-2-(N,N-disubstituted aminomethyl)pyrrolidine and butyllithium. Chiral allylic alcohols were obtained with moderate to high enantiomeric excesses (ee’s) (41–92% ee) from several cyclic and acyclic epoxides employing lithium (S)-2-(1-pyrrolidinylmethyl)pyrrolidide in tetrahydrofuran (THF) in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).
Asymmetric aldol-type reaction between both achiral ketene silyl acetals of acetic acid esters and aldehydes by the use of a chiral promoter
作者:Teruaki Mukaiyama、Shū Kobayashi、Tetsuya Sano
DOI:10.1016/s0040-4020(01)85587-3
日期:——
aldol-type reaction between achiral ketene silyl acetals of acetic acid esters and achiral aldehydes is successfully carried out by the use of a chiral promoter, a combined use of chiral diamine coordinated tin(II) trifluoromethanesulfonate (tin(II) triflate) and tributyltin fluoride. The structure of this new promoter and the mechanism of the present asymmetric aldol-type reaction are discussed.
Selective reduction of secondary amides to amines in the presence of tertiary amides
作者:Byung H. Lee、Michael F. Clothier
DOI:10.1016/s0040-4039(98)02509-x
日期:1999.1
Secondary amides activated with a Cbz group can be reduced to their corresponding hemiaminals using lithium borohydride. Hydrogenation then removes the Cbz and hydroxyl groups to produce the related amine. Tertiary amides are not affected.
The invention relates to a cholinesterase activator comprising, as an active ingredient, a compound represented by the following general formula (I):
wherein A means a group such as a phenyl group or indanyl group, B denotes a group such as a prolyl group or thioprolyl group, and m stands for an integer of 0-5.
The cholinesterase activator according to the invention has a strongly activating action on cholinesterase, in particular, a selectively activating action on peripheral cholinesterase and is also high in safety. It is hence useful as an agent for preventing and treating the side effects of central cholinesterase inhibitors, in particular, hepatopathy, and an agent for preventing and treating the side effects of various medicines manifested on the basis of a cholinesterase-inhibiting action.
本发明涉及一种胆碱酯酶激活剂,其活性成分包括由以下通式(I)代表的化合物:
其中 A 表示苯基或茚基等基团,B 表示脯氨酰基或噻丙酰基等基团,m 代表 0-5 的整数。
本发明的胆碱酯酶激活剂对胆碱酯酶有强烈的激活作用,特别是对外周胆碱酯酶有选择性激活作用,而且安全性高。因此,它可用作预防和治疗中枢性胆碱酯酶抑制剂副作用(尤其是肝病)的药物,以及预防和治疗以胆碱酯酶抑制作用为基础的各种药物副作用的药物。