α-Amino Acids andN-Protected α-Amino Aldehydes by Stereoselective Additions of a Chiral Vinyllithium Reagent to Sulfonylimines
作者:Manfred Braun、Kersten Opdenbusch
DOI:10.1002/jlac.199719970121
日期:1997.1
proven by conversion into the oxazolidinones 16a–d whose optical purity is determined to exceed 92% e.e. by 1H-NMR measurements in the presence of chiralshiftreagents. The sulfonylimine 21a and a series of para-substituted derivatives 21b–h are also allowed to react with the vinyllithium reagent 1b to give mixtures of diastereomers 22/23. The logarithms of the diastereomeric ratios 22:23 correlate with
Substituted benzamides. 1. Potential nondopaminergic antagonists of chemotherapy-induced nausea and emesis
作者:Ivo Monkovic、David Willner、Michael A. Adam、Myron Brown、R. R. Crenshaw、Carl E. Fuller、Peter F. Juby、George M. Luke、John A. Matiskella、Thomas A. Montzka
DOI:10.1021/jm00403a011
日期:1988.8
A series of new substitutedbenzamides has been synthesized and evaluated for dopamine antagonist activity and for antagonism of cisplatin-induced emesis in the dog and in the ferret. It was found that modification of the 2-methoxy substituent of metoclopramide was detrimental to dopaminergic D2 antagonism but not necessarily to antagonism of cisplatin-induced emesis. A number of analogues having a
A Useful Preparation of<i>O</i>-Protected α-Hydroxyketones of Defined Enantiomeric Purity from 2-Hydroxyalkanoic Esters
作者:Marc Larchevêque、Yves Petit
DOI:10.1055/s-1986-31478
日期:——
α-Hydroxyketones (OH-protected) are prepared in high enantiomeric purity by reaction of chiral O-protected 2-hydroxyalkanoic esters with organolithium compounds in ether/pentane at - 100°C or by conversion of 2-hydroxyalkanoic esters into 2-hydroxy-N,N-dimethylalkanamides, O-protection of these amides, and reaction with organomagnesium bromides in tetrahydrofuran/ether at 5°C.