Abstract: A process of preparing an optically active halohydrin compound characterized by comprising asymmetric hydrogen transfer reduction of an ?-haloketone compound in the presence of a group 9 transition metal compound having a substituted or unsubstituted cyclopentadienyl group and an optically active diamine compound. The asymmetric hydrogen transfer reduction is preferably conducted in the presence of a base.

Abstract: The present invention provides a method for efficiently producing &bgr;-D-ribofuranose derivatives or optical isomers thereof, useful as synthetic intermediates of pharmaceutical nucleic acid-series products. The method comprises a step of producing 1-O-benzyl-&bgr;-D-ribofuranose-2,3,5-triacetate or an optical isomer thereof by allowing &bgr;-D-ribofuranose-1,2,3,5-tetraacetate or an optical isomer thereof to react with a benzyl alcohol in the presence of acid catalysts and a step of hydrolyzing the resulting 1-O-benzyl-&bgr;-D-ribofuranose-2,3,5-triacetate in the presence of a base to produce 1-O-benzyl-&bgr;-D-ribofuranose or an optical isomer thereof.

Abstract: An N-9-position alkylated form is selectively precipitated by subjecting a mixture containing the N-9-position alkylated form and an N-7-position alkylated form of 2-amino-6-halopurine to a crystallization step using a mixed solvent of an organic solvent and water. Then, this N-9-position alkylated form is reduced to give famciclovir. By this method of the present invention, famciclovir known as an antiviral agent, and an intermediate compound therefor can be efficiently produced.

Abstract: A process of preparing an optically active halohydrin compound characterized by comprising asymmetric hydrogen transfer reduction of an &agr;-haloketone compound in the presence of a group 9 transition metal compound having a substituted or unsubstituted cyclopentadienyl group and an optically active diamine compound. The asymmetric hydrogen transfer reduction is preferably conducted in the presence of a base.

Abstract: A process for producing &agr;-amino-dihalogenated methyl ketone derivatives by reacting an N-protected &agr;-amino acid ester with a dihalomethyl lithium is provided. This process is suitable for the production on an industrial scale and by this process, &agr;-amino-dihalogenated methyl ketone derivatives and &bgr;-amino-&agr;-hydroxycarboxylic acid derivatives can be obtained efficiently and economically advantageously.

Abstract: An N-9-position alkylated form is selectively precipitated by subjecting a mixture containing the N-9-position alkylated form and an N-7-position alkylated form of 2-amino-6-halopurine to a crystallization step using a mixed solvent of an organic solvent and water. Then, this N-9-position alkylated form is reduced to give famciclovir. By this method of the present invention, famciclovir known as an antiviral agent, and an intermediate compound therefor can be efficiently produced.

Abstract: The present invention provides a method for efficiently producing &bgr;-D-ribofuranose derivatives or optical isomers thereof, useful as synthetic intermediates of pharmaceutical nucleic acid-series products. The method comprises a step of producing 1-O-benzyl-&bgr;-D-ribofuranose-2,3,5-triacetate or an optical isomer thereof by allowing &bgr;-D-ribofuranose-1,2,3,5-tetraacetate or an optical isomer thereof to react with a benzyl alcohol in the presence of acid catalysts and a step of hydrolyzing the resulting 1-O-benzyl-&bgr;-D-ribofuranose-2,3,5-triacetate in the presence of a base to produce 1-O-benzyl-&bgr;-D-ribofuranose or an optical isomer thereof.

Abstract: A process for producing &agr;-amino-dihalogenated methyl ketone derivatives by reacting an N-protected &agr;-amino acid ester with a dihalomethyl lithium is provided. This process is suitable for the production on an industrial scale and by this process, &agr;-amino-dihalogenated methyl ketone derivatives and &bgr;-amino-&agr;-hydroxycarboxylic acid derivatives can be obtained efficiently and economically advantageously.

Abstract: A composite material wherein a mixture of a phenolic or furan resin and an inorganic filler as matrix materials is incorporated in an inorganic fiber or heat-resistant organic fiber in the form of a long fiber bundle. The composite material has excellent characteristics such as heat resistance, strength and alkali resistance. The present invention can provide substitutes used in place of concrete reinforcing steel bars or steel frames which can be used in structures for building and civil engineering.