Abstract: A process for the efficient production of a D-amino acid from the corresponding DL-5-substituted hydantoin by one-step reaction which comprises using a composite immobilized enzyme at a pH about neutrality, said composite immobilized enzyme being obtained by immobilizing a hydantoinase having its optimal pH within an alkaline range and a D-N-carbamyl-.alpha.-amino acid amidohydrolase having its optimal pH about neutrality in a coexisting state on an immobilizing support, simultaneously, is disclosed.

Abstract: An object of the present invention is to provide a safe method of commercially producing optically active aminoalcohol derivatives, which serve as intermediates for the synthesis of medicinal chemicals such as the immunopotentiating anticancer agent bestatin, in a simple and easy manner in high yields and with high levels of selectivity.The present invention consists in a method of producing 3-amino-1-nitro-4-phenyl-2-butanol derivatives of the general formula (1) ##STR1## wherein R.sup.1 and R.sup.2 each independently represents a hydrogen atom or an amino group protecting group, and a method of producing 3-amino-2-hydroxy-4-phenylbutyric acid derivatives derivable therefrom.

Abstract: A process for preparing an enol silyl ether compound from a diazoacetoacetic acid ester having the general formula (IV): ##STR1## wherein R.sup.1 is a lower alkyl group having 1 to 6 carbon atoms, phenyl group, a substituted phenyl group, an aralkyl group or allyl group, and R.sup.2, R.sup.3 and R.sup.4 are the same or mutually different and each is a lower alkyl group having 1 to 6 carbon atoms, which comprises reacting a diazoacetoacetic acid ester having the general formula (I): ##STR2## wherein R.sup.1 is the same as defined above, with a trialkylsilyl chloride having the general formula (II): ##STR3## wherein R.sup.2, R.sup.3 and R.sup.4 are the same as defined above, in an inert solvent in the presence of an organic base and an alkali halide having the general formula (III):MX (III)wherein M is an alkaline metal and X is bromine atom or iodine atom. The desired compound is useful as an intermediate for synthesis of carbapenem .beta.-lactam antibiotics.

Abstract: A novel process for effectively preparing an optically active cyanohydrin comprising asymmetrically cyanating an aldehyde by reacting the aldehyde with a cyanating agent in the presence of a titanate of an optically active tartaric acid derivative.

Abstract: A process for preparing trans-.beta.-benzoylacrylic acid ester having the general formula (I): ##STR1## wherein R is alkyl group or aralkyl group, which comprises dealcoholizing .beta.-benzoyl-.alpha.-alkoxypropionic acid ester having the general formula (II): ##STR2## wherein R is above, in the presence of an acid catalyst to give trans-.beta.-benzoylacrylic acid ester having the general formula (I).According to the process of the present invention, the by-product (II) produced in the esterification reaction of .beta.-benzoylacrylic acid (III) with the alcohol (V) by the dehydration reaction can be converted into the compound (I) by the dealcoholization reaction in the presence of the acid catalyst and thus trans-.beta.-benzoylacrylic acid ester (I) with a high purity can be produced in an industrially advantageous manner.

Abstract: Ethyl-.beta.-benzoyacrylate is reacted with an alkali metal salt of (S)-alanine or an alkali metal salt of N.sup.6 -trifluoroacetyl-L-lysine to form the corresponding Michael addition product, and not less than an equivalent amount of acid is added after completion of the Michael addition to prevent conversion of the (S,S) form of the product to the (R,S) form.

Abstract: A process for preparing a 4-acetoxy-3-hydroxyethylazetidin-2-one derivative having the formula (II): ##STR1## wherein R.sup.1 is a protective group for the hydroxyl group, which comprises reacting a .beta.-lactam compound having the formula (I): ##STR2## wherein R.sup.1 is as defined above, and R.sup.2, R.sup.3 and R.sup.4 are a lower alkyl group having 1 to 6 carbon atoms, phenyl group or an aralkyl group, with acetic anhydride in an organic solvent in the presence of a low concentration of a substituted pyridine. According to the present invention, there can be obtained 4-acetoxy-3-hydroxyethylazetidin-2-one derivatives, which are useful intermediates for preparing carbapenem .beta.-lactam antibiotics.

Abstract: A process for preparing a 4-acetoxy-3-hydroxyethylazetidin-2-one derivative having the formula (II): ##STR1## wherein R.sup.1 is a protective group for the hydroxyl group, which comprises reactig a .beta.-lactam compound having the formula (I): ##STR2## wherein R.sup.1 is as difined above and R.sup.2, R.sup.3 and R.sup.4 are the same or different and each is a lower alkyl group having 1 to 4 carbon atoms or an aralkyl group, with acetic anhydride in the presence of a base and a catalyst selected from the group consisting of an organic strong acid, a mineral acid, a Lewis acid, a halogenated acyl compound having the formula (IV):R.sup.8 --CO--X (IV)wherein R.sup.8 is an alkyl group, an aralkyl group or phenyl group and X is a halogen atom, a halogenated sulfonyl compound having the formula (V):R.sup.9 --SO.sub.2 --X (V)wherein R.sup.9 is an alkyl group, an aralkyl group or phenyl group and X is a halogen atom, and a compound having the formula (VI):(R.sup.10).sub.4-n --Si(X').sub.n (VI)wherein R.sup.

Abstract: A process for preparing optically active indoline-2-carboxylic acid by an optical resolution, which comprises subjecting a racemic ester of (R,S)-indoline-2-carboxylic acid having the general formula [(R,S)-I] to the action of an enzyme or a microorganism having a stereo-selective esterase activity, which is capable of asymmetrically hydrolyzing the racemic ester [(R,S)-I] to give optically active indoline-2-carboxylic acid having the formula [II*] so as to produce the hydrolysis product, i.e. optically active indoline-2-carboxylic acid [II*] and an unreacted optically active ester of indoline-2-carboxylic acid having the general formula [I*], isolating each optically active form, and further, if necessary, hydrolyzing the obtained optically active ester [I*] to give an optical antipode of the acid [II*].According to the process of the present invention, optically active indoline-2-carboxylic acid with a high optical purity can be prepared in a simple process with a good yield.

Abstract: A process for preparing optically active glycerol derivatives by a biochemical resolution which comprises (i) subjecting an ester having the general formula [(R,S)-I]: ##STR1## wherein X is a halogen atom, R is an aliphatic hydrocarbon group of C.sub.1 to C.sub.8 and R' is an aromatic hydrocarbon group or an aliphatic hydrocarbon group of C.sub.1 to C.sub.2, to the action of enzymes derived from either microorganisms or animal organs, wherein said enzymes have a stereo selective esterase activity to asymmetrically hydrolyze the ester having the general formula [(R,S)-I] to give a mixture of an optically active alcohol having the general formula (II)*: ##STR2## wherein X and R' are as above and an optically active ester having the general formula (I)*: ##STR3## wherein X, R and R' are as above, and (ii) obtaining the optically active alcohol having the general formula (II)* and the optically active ester having the general formula (I)* by separating operations.

Abstract: A process for preparing a 4-acetoxy-3-hydroxyethylazetidin-2-one derivative having the formula (II): ##STR1## wherein R.sup.1 is a protective group for the hydroxyl group, which comprises reacting a .beta.-lactam compound having the formula (I): ##STR2## wherein R.sup.1 is as defined above, R.sup.2, R.sup.3 and R.sup.4 are a lower alkyl group having 1 to 6 carbon atoms, phenyl group or an aralkyl group and R is a protective group for N, with acetic anhydride in an organic solvent in the presence of a base, and removing the protective group for N.4-Acetoxy-3-hydroxyethylazetidin-2-one derivatives are useful intermediates for preparing carbapenem .beta.-lactam antibiotics such as thienamycin and penem .alpha.-lactam antibiotics.

Abstract: A process for preparing 3-halogeno-2-hydroxy-propyltrimethylammonium halide or especially one having the (S)-configuration, which comprises reacting 2,3-dihydroxypropyltrimethylammonium halide or one having the (S)-configuration, which is obtained by reacting (R)-3-halogeno-1,2-propanediol with trimethylamine, with a halogenating reagent.According to the present invention, 3-halogeno-2-hydroxypropyltrimethylammonium halide or one having the (S)-configuration, which is a useful intermediate for the synthesis of carnitine or especially (l)-carnitine, can be obtained economically, efficiently and easily.

Abstract: The present invention relates to .beta.-lactam compound having the formula (I): ##STR1## wherein R.sup.1 is a trialkylsilyl group, dimethyl-1,1,2-trimethylpropylsilyl group, acetyl group, benzyloxycarbonyl group, O-nitrobenzyloxycarbonyl group, p-nitrobenzyloxycarbonyl group or t-butyl group, R.sup.2, R.sup.3 and R.sup.4 are a member selected from the group consisting of a lower alkyl group having 1 to 6 carbon atoms, phenyl group and an aralkyl group and a process for preparing the compound which comprises reacting enolsilylethers having the formula (III): ##STR2## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are as above, with chlorosulfonylisocyanate and then reducing the obtained product. The .beta.-lactam compound of the present invention is a useful intermediate for preparing carbapenem .beta.-lactam compound.

Abstract: An inorganic acid salt of N-[1(S)-ethyoxycarbonyl-3-phenylpropyl]-L-alanylchloride having the formula (I): ##STR1## A process for preparing an inorganic acid salt of N-[1(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanylchloride having the formula (I) ##STR2## which comprises reacting an inorganic acid salt of N-[1(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanine with phosphorous pentachloride in an inactive organic solvent. According to the present invention, ACEI can be economically and easily prepared.

Abstract: A method for producing optically active glycol derivatives by biochemical resolution which comprises contacting a racemic ester of the general formula 1 ##STR1## (wherein R.sub.1 is an aliphatic hydrocarbon group of 1 to 16 carbon atoms, R.sub.2 is an aliphatic hydrocarbon group of 1 to 8 carbon atoms, and R.sub.3 is an aromatic hydrocarbon group such as phenyl, tolyl or naphtyl) with a microorganism- or animal organ-derived enzyme having stereoselective hydrolytic activity to asymmetrically hydrolyze said racemic ester of general formula 1 to produce an optically active alcohol of general formula 2* ##STR2## (wherein R.sub.1 and R.sub.3 have the same meanings as defined above) and an unreacted ester of the general formula 1* ##STR3## (wherein R.sub.1, R.sub.2 and R.sub.

Abstract: A process for preparing N-[1(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanyl-L-proline, which comprises reacting N-carboxyanhydride of N-[1(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanine with L-proline in the presence of a base. According to the process, enalapril can be prepared economically, easily and effectively.

Abstract: A sulfate of tetrahydrobiopterin having the formula (I): ##STR1## and a process for preparing the same, which comprises crystallizing tetrahydrobiopterin from an aqueous medium containing sulfuric acid.

Abstract: A process for preparing tetrahydrobiopterin which is rich in the (6R)-form, which comprises hydrogenating L-erythrobiopterin in a basic medium in the presence of a platinum group catalyst. According to the process, tetrahydrobiopterin improved in (6R)/(6S) ratio can be easily obtained in the high yield.

Abstract: An improved process for preparation of an optically active N-(3-mercapto-2-D-methylpropanoyl)-L-amino acid represented by formula (I): ##STR1## from an N-(3-chloro-2-D-methylpropanoyl)-L-amino acid represented by formula (II): ##STR2## (Y in (I) and (II): CH.sub.2 or sulfur; Q in (II): hydrogen, Na, K or NH.sub.4),which is characterized by reacting the compound (II) with an alkali trithiocarbonate, of which the molar ratio to the compound (II) is not less than 1.5, in an aqueous medium at a temperature of from about 60.degree. C. to about 90.degree. C., and hydrolyzing the resulting product with an acid.It is preferable to use sodium trithiocarbonate as the alkali trithiocarbonate, mineral acid as the acid, or water or aqueous alcohol as an aqueous medium.

Abstract: An object of the present invention is to provide a safe method of commercially producing optically active aminoalcohol derivatives, which serve as intermediates for the synthesis of medicinal chemicals such as the immunopotentiating anticancer agent bestatin, in a simple and easy manner in high yields and with high levels of selectivity.The present invention consists in a method of producing 3-amino-1-nitro-4-phenyl-2-butanol derivatives of the general formula (1) ##STR1## wherein R.sup.1 and R.sup.2 each independently represents a hydrogen atom or an amino group protecting group, and a method of producing 3-amino-2-hydroxy-4-phenylbutyric acid derivatives derivable therefrom.