Abstract: Indene derivatives that are utilizable as intermediates in the synthesis of the vitamin D2 derivative paricalcitol, which is useful as pharmaceutical are efficiently prepared by subjecting a vitamin D2 derivative such as 25-hydroxyvitamin D2 to a two-steps oxidation reaction using an oxidizing agent such as potassium permanganates and sodium periodate in a suitable solvent such as methanol and ethanol.

Abstract: The invention offers a method of hydrogenating camptothecin in inert solvent in the presence of nickel catalyst, whereby selective hydrogenation of camptothecin can be very efficiently accomplished using the low-cost catalyst.

Abstract: A cyclovitamin D derivative produced from 25-hydroxyvitamin D is reacted with osmium tetraoxide or a permanganic acid salt to produce a 10,19-diolcyclovitamin D derivative. The 10,19-diolcyclovitamin D derivative is reacted with a perhalogenic acid salt or lead tetraacetate to produce a 10-oxocyclovitamin D derivative. A 1-hydroxycyclovitamin D derivative is produced from the 10-oxocyclovitamin D derivative via a cyclovitamin D derivative and a 1,10-olefincyclovitamin D derivative. The 1-hydrocyclovitamin D derivative is subjected to solvolysis, thereby producing a 1-hydroxy-19-norviatmin D derivative. Thus provided are a novel process for production of 1-hydroxy-19-norcyclovitamin D derivative that is utilizable as an intermediate in the synthesis of 1-hydroxy-19-norvitamin D derivative which is useful as a pharmaceutical agent; and an intermediate for the production.

Abstract: The invention offers a method of hydrogenating camptothecin in inert solvent in the presence of nickel catalyst, whereby selective hydrogenation of camptothecin can be very efficiently accomplished using the low-cost catalyst.

Abstract: Indene derivatives that are utilizable as intermediates in the synthesis of the vitamin D2 derivative paricalcitol, which is useful as pharmaceutical are efficiently prepared by subjecting a vitamin D2 derivative such as 25-hydroxyvitamin D2 to a two-steps oxidation reaction using an oxidizing agent such as potassium permanganates and sodium periodate in a suitable solvent such as methanol and ethanol.

Abstract: A method for manufacturing (R)-tetrahydrothiophene-3-ol denoted by formula (II): by bioconversion of tetrahydrothiophene-3-one denoted by formula (I): to (R)-tetrahydrothiophene-3-ol denoted by formula (II). It comprises the steps of: (A) incubating the tetrahydrothiophene-3-one denoted by formula (I) in the presence of a strain, or a preparation of a cultured cell thereof, belonging to Penicillium, Aspergillus, or Streptomyces that is capable of said bioconversion; and (B) collecting the (R)-tetrahydrothiophene-3-ol denoted by formula (II) from incubated solution. A method for crystallization of optically active tetrahydrothiophene-3-ol of improved optical purity, characterized by maintaining a solution comprising optically active tetrahydrothiophene-3-ol and organic solvent at equal to or lower than 1° C.

Abstract: Provided is a method of preparing a hydroxyamino acid derivative, particularly in an optically active form thereof with high efficiency.

Abstract: Provided is a process for producing an isocoumarin-3-yl-acetic acid derivative, characterized by reacting a homophthalic acid derivative represented by a formula: (wherein Rc, R2 and R are mainly protecting groups) with a malonic acid derivating represented by a formula: (wherein R is an organic group including a lower alkyl group; R3 is a protecting group for a carboxyl group; and X is a halogen atom or a —OM group (wherein M is alkaline metal or alkaline earth metal)). According to the above process, various isocoumarin-3-yl-acetic acid derivatives can efficiently be provided.

Abstract: Provided is a process for producing an isocoumarin-3-yl-acetic acid derivative, characterized by reacting a homophthalic acid derivative represented by a formula: 1

Abstract: Provided is a process for producing an isocoumarin-3-yl-acetic acid derivative, characterized by reacting a homophthalic acid derivative represented by a formula: (wherein Rc, R2 and R are mainly protecting groups) with a malonic acid derivating represented by a formula: (wherein R is an organic group including a lower alkyl group; R3 is a protecting group for a carboxyl group; and X is a halogen atom or a —OM group (wherein M is alkaline metal or alkaline earth metal)). According to the above process, various isocoumarin-3-yl-acetic acid derivatives can efficiently be provided.