Abstract: A process for preparing optically active alcoholic compounds wherein a carbonyl compound is assymmetrically reduced in an economical and practical manner. The process comprises treating a prochiral carbonyl compound represented by the general formula (1) with an optically active organoaluminum compound represented by the general formula (2) to conduct asymmetric reduction, thereby preparing an optically active alcoholic compound represented by the general formula (3).

Abstract: The present invention provides a process for reducing carbonyl compounds to hydroxy compounds, in particular stereoselectively reducing .alpha.-aminohaloketone derivatives, under mild conditions in an easy and simple manner, which comprises reacting a carbonyl compound of the general formula (1) with an organoaluminum compound of the general formula (4) to provide the corresponding alcohol compound of the general formula (5).

Abstract: The present invention has for its object to provide a commercially useful, expedient and efficient method for purification and isolation of an N-protected (2S,3R)-1-halo-2-hydroxy-3-amino-4-phenylthiobutane (1) or its enantiomer, which is capable of removing the various contaminants, particularly said byproducts, whereby the problem of instability of the compound (1) or its enantiomer can be overcome and a high product yield can be insured.The present invention relates to a method of purifying and isolating an N-protected (2S,3R)-1-halo-2-hydroxy-3-amino-4-phenylthiobutane (1): ##STR1## (wherein X represents a halogen atom; one of P.sup.1 and P.sup.2 represents a hydrogen atom and the other represents an amino-protecting group, or P.sup.1 and P.sup.

Abstract: An object of the present invention is to provide a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative via efficient and industrially utilizable steps.The present invention provides a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative represented by the general formula (2) given below which comprises hydrolyzing an .alpha.-amino-.alpha.', .alpha.-dihaloketone derivative of the general formula (1) given below in the presence of a base, followed by protecting the amino group or without protecting the same.

Abstract: An object of the present invention is to provide a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative via efficient and industrially utilizable steps.The present invention provides a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative represented by the general formula (2) given below which comprises hydrolyzing an .alpha.-amino-.alpha.', .alpha.'-dihaloketone derivative of the general formula (1) given below in the presence of a base, followed by protecting the amino group or without protecting the same.

Abstract: The present invention provides a process for producing 1,2-epoxy-3-amino-4-phenylbutane derivatives which comprises treating a 1-halo-2-hydroxy-3-amino-4-phenylbutane derivative with a base in an aprotic polar organic solvent or a mixed solvent composed of an aprotic polar organic solvent and water and then causing the resulting epoxide to crystallize out from a mixed solvent composed of an aprotic polar organic solvent and water.

Abstract: Processes for efficiently producing .alpha.-halo ketones, .alpha.-halohydrins and epoxides on an industrial scale. The prosesses include one for producing an .alpha.-halo ketone of general formula (3) by decarboxylating a product of reaction between a carboxilic acid derivative of general formula (1) and a metal enolate prepared from an .alpha.-haloacetic acid of general formula (2) or an acceptable salt thereof, one for producing an by reducing the .alpha.-halo ketone (3), and one for producing an epoxide (13) by treating the .alpha.-halohydrin (11) with a base to effect ring closure. The above prosesses are particularly suitable for producing optically active .alpha.-halo ketones, .alpha.-halohydrins and epoxides from the corresponding .alpha.-amino acid derivatives.

Abstract: A process for producing optically active 1-halo-3-amino-4-phenyl-2-butanol derivatives from optically active 1-halo-3-amino-4-phenyl-2-butanone derivatives stereoselectively in a high yield by bringing the butanone derivatives into contact with microorganisms.