Abstract: The present invention provides a novel crystal of alanine alkyl ester sulfonate having low hygroscopicity and low corrosiveness, which can be produced industrially economically. The present invention provides crystals of alanine alkyl ester sulfonates represented by formula (1): wherein R1 is a methyl group or an ethyl group, provided that when R1 is a methyl group, R2is an ethylphenyl group or a dimethylphenyl group; and when R1 is an ethyl group, R2 is a methyl group, a phenyl group, a chlorophenyl group, an ethylphenyl group, or a dimethylphenyl group.

Abstract: The present invention provides a novel crystal of alanine alkyl ester sulfonate having low hygroscopicity and low corrosiveness, which can be produced industrially economically. The present invention provides crystals of alanine alkyl ester sulfonates represented by formula (1): wherein R1 is a methyl group or an ethyl group, provided that when R1 is a methyl group, R2is an ethylphenyl group or a dimethylphenyl group; and when R1 is an ethyl group, R2 is a methyl group, a phenyl group, a chlorophenyl group, an ethylphenyl group, or a dimethylphenyl group.

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: 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: Spherical aggregate crystals of a phosphoric acid/lysine/magnesium composite salt represented by formula (1):R.sub.a Mg.sub.b H.sub.c PO.sub.4.(H.sub.2 O).sub.n (1)whereR is a lysine cation;a is 0.15 to 1.0;b is 1.0 to 1.42;c is 0 to 0.3;n is 0 to 10; anda+(2.times.b)+c=3.

Abstract: A process for optical resolution of a racemic substituted benzylamine is provided that involves reacting the racemic substituted benzylamine in a solvent with an optically active N-acyl-phenylalanine, -aspartic acid, or -glutamic acid, and separating the diastereomers formed by making use of the difference in the mutual solubilities of the two diastereomer salts which are generated therein.

Abstract: The present specification discloses a ruminant feed additive composition which contains as an active ingredient a phosphoric acid-amino acid-polyvalent metal composite salt (final composite salt) which is insoluble in neutral or alkaline water and is soluble in acidic water and which can be obtained by treating a composite salt composed of a basic amino acid, magnesium and phosphoric acid with a salt of a divalent or trivalent (polyvalent) metal other than magnesium, or by treating the above-mentioned composite salt with the polyvalent metal salt and a condensed phosphoric acid component (alone) or the condensed phosphoric acid component and a phosphoric acid component (in combination), this composition taking the form of a powder or granules.

Abstract: An economical process for producing .alpha.-L-aspartyldipeptide amide derivatives useful as sweeteners, by using amino protecting groups which can be removed by hydrolysis under acidic conditions, resulting in conversion of a .beta.-carboxyl acid ester to a carboxylic acid.

Abstract: L-amino acid amides are converted to the corresponding D-amino acid amides. An amide formed from an L-amino acid and an optically active (S)-.alpha.-alkylbenzylamine is subjected to dehydration condensation with an aryl aldehyde to form a Schiff's base, which is racemized at the amino acid moiety in the presence of a base to yield an N-allylidene-D-amino acid-(S)-amide. The less-soluble diastereomer N-allylidene-D-amino acid-(S)-amide is crystallized from the reaction mixture and recovered by means of solid/liquid separation. The N-allylidene form is readily hydrolyzed into the amino acid-(S)-amide and the starting aldehyde.

Abstract: To produce optically active .alpha.-arylalkylamine from optically impure .alpha.-arylalkylamine.Optically impure .alpha.-arylalkylamine is mixed with optically active N-acyl-aspartic acid or glutamic acid in a solvent and the resulting two types of diastereomer salts are optically resolved utilizing difference in solubility.

Abstract: The present invention provides crystals of L-phenylalanine monomethyl sulfate which have low solubility compared to L-tyrosine and D-phenylalanine. The L-phenylalanine monomethylsulfate crystals are obtained by subjecting a solution containing monomethyl sulfuric acid and phenylalanine to crystallization.Further, the present invention also provides a process for recovering L-phenylalanine from a water layer by neutralizing the esterified reaction, extracting an ester of L-phenylalanine therefrom with an organic solvent, and recovering remaining L-phenylalanine in the water layer as L-phenylalanine monomethylsulfate. L-phenylalanine monomethyl sulfate is obtained by esterifying L-phenylalanine and methanol in the presence of sulfuric acid, neutralizing the esterified solution with a base in the presence of water, extracting the produced L-phenylalanine methyl ester from the neutralized solution with an organic solvent, and then crystallized the resultant water layer under acidic condition.

Abstract: The present invention provides a method of preparing L-aspartyl-D-.alpha.-aminoalkane carboxylic acid-(S)-N-.alpha.-alkylbenzylamide which is less expensive and more efficient than previous methods using N-protected-L-aspartic anhydride.

Abstract: A process for improving the yield of crystallization of L-phenylalanine monomethyl sulfate from an aqueous solution containing L-phenylalanine and monomethyl sulfate, by adding an effective crystallization improving amount of a salt of an inorganic or organic acid with an alkali metal, an alkaline earth metal or ammonium, to the aqueous solution.

Abstract: Addition of a reaction mixture obtained by the mineral acid hydrolysis of at least one side flow generated from the production of .alpha.-L-aspartyl-L-phenylalanine methyl ester to a crystallization slurry containing L-phenylalanine while maintaining the pH of the slurry at 3-8 by adding aqueous alkali affords crystallized L-phenylalanine having a low water content in a high yield.

Abstract: The present invention provides crystals of L-phenylalanine monomethyl sulfate which have low solubility compared to L-tyrosine and D-phenylalanine. The L-phenylalanine monomethylsulfate crystals are obtained by subjecting a solution containing monomethyl sulfuric acid and phenylalanine to crystallization.Further, the present invention also provides a process for recovering L-phenylalanine from a water layer by neutralizing the esterified reaction, extracting an ester of L-phenylalanine therefrom with an organic solvent, and recovering remaining L-phenylalanine in the water layer as L-phenylalanine monomethylsulfate. L-phenylalanine monomethyl sulfate is obtained by esterifying L-phenylalanine and methanol in the presence of sulfuric acid, neutralizing the esterified solution with a base in the presence of water, extracting the produced L-phenylalanine methyl ester from the neutralized solution with an organic solvent, and then crystallized the resultant water layer under acidic condition.

Abstract: Disclosed herein is a process for separating N-protected-.alpha.-L-aspartyl-L-phenylalanine, more particularly a process for selectively separating N-protected-.alpha.-L-aspartyl-L-phenylalanine from a solution of N-protected-.alpha.-L-aspartyl-L-phenylalanine containing at least N-protected-.alpha.-L-aspartyl-D-phenylalanine as impurity.

Abstract: Tripeptide sweeteners represented by formula (I)X--Asp--Y--ORwhereinX is glycine or a D or DL-isomer of alanine, .alpha.-aminobutyric acid, serine, threonine, norvaline, asparagine, B-methyl aspartate, proline or pipecolic acid, andY is a D, L or DL-isomer of alanine, phenylalanine, phenylglycine, serine or .beta.-aminobutyric acid or a salt thereof, andR is methyl, ethyl, propyl or isopropyl, are disclosed.

Abstract: The invention relates to a process for producing N-protected-.alpha.L-aspartyl-L-phenylalanine methyl ester, which comprises esterifying L-phenylalanine with methanol in the presence of a strong acid catalyst, adding, to the resulting solution, an aqueous alkaline solution to neutralize the acid catalyst and a water-immiscible organic solvent to extract the free L-phenylalanine methyl ester thus formed, collecting the organic layer, and reacting the L-phenylalanine methyl ester dissolved in said collected organic layer with N-protected-L-aspartic anhydride.

Abstract: In a method for the manufacture of N-formylaspartic acid anhydride which comprises reacting a mixture of aspartic acid, formic acid and acetic anhydride in the presence of an entraining organic solvent, the improvement comprising adding to the mixture, prior to or during the course of reaction, an oxide, hydroxide, or a salt of a metal. The above compound is used as an intermediate in the manufacture of alpha-L-aspartyl-L-phenylalanine methyl ester which is a sweetening agent.

Abstract: An elevator passenger traffic measuring system distributes passengers whose destination floors cannot be determined to each of origin-destination floor pairs in accordance with an elevator car position, an incoming passenger number and an outgoing passenger number at each floor, and registered car calls, using probability weights for the origin-destination floor pairs which are determined by previous traffic measurements. The system then estimates the number of passengers for each of the origin-destination floor pairs in accordance with the distributed passengers, and the passengers who moved the corresponding one of the origin-destination floor pairs.