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 novel phosphoric acid-amino acid complex salt is provided which manifests insolubility in a neutral or alkaline aqueous solution and solubility in an acidic aqueous solution and has a basic amino acid, an alkaline earth metal, and phosphoric acid as main components thereof. An additive composition containing the complex salt and used in a feed for ruminant mammals excels in protection in the first compartment of the stomach of a ruminant mammal and solubility in the fourth compartment of the stomach. This additive composition improves the nutrition of the feed with respect to such a basic amino acid as lysine, a substance frequently missing in the feed for ruminant mammals.

Abstract: A ruminant feed additive composition comprises a phosphoric acid-amino acid composite salt and a water-insoluble salt of a polyvalent-metal-sensitive water-soluble high-molecular weight substance. The composite salt contains a basic amino acid, an alkaline-earth metal and phosphoric acid, and is insoluble in neutral or alkaline aqueous solution, but is soluble in acidic aqueous solution.

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: A ruminant feed additive composition in the form of a powder or granules comprises as active ingredients a gastric antacid, a phosphoric acid-amino acid-polyvalent metal composite salt and optionally a water-insoluble salt of a polyvalent metal-sensitive water-soluble high-molecular weight substance. The phosphoric acid-amino acid-polyvalent metal composite salt is composed of a phosphoric acid such as orthophosphoric acid, a polyphosphoric acid or a metaphosphoric acid, a basic amino acid such as lysine or methionine, an alkaline earth metal such as calcium or magnesium and, optionally, a polyvalent metal such as aluminum.

Abstract: A crude 2',3'-dideoxynucleoside compound is purified by extracting with an organic solvent, or crystallizing, the 2',3'-dideoxynucleoside compound from a basic aqueous solution having a pH of not less than 12 containing the same. In another embodiment of purification a basic aqueous solution having a pH of not less than 11 of a crude 2',3'-dideoxynucleoside derivative is brought into contact with a nonpolar porous resin, whereby the derivative is adsorbed on the resin, and then the thus adsorbed derivative is desorbed with an aqueous alcoholic solution.2',3'-Dideoxynucleoside compounds which have utility as anti-AIDS drugs or anti-virus drugs can be isolated and purified in high purity and in high yield from their crude products containing impurities.

Abstract: A readily soluble 2',3'-dideoxyinosine composition is prepared by combining 80 to 1 parts by weight of a basic amino acid and 20 to 99 parts by weight of 2',3'-dideoxyinosine. The greater solution velocity of this composition improves solubility for therapeutic uses.

Abstract: A method of purifying .alpha.-L-aspartyl-L-phenylalanine methyl ester as a hydrochloride salt thereof which comprises:i) contacting a mixture of .alpha.-L-aspartyl-L-phenylanaline methyl ester and .beta.-L-aspartyl-L-phenylalanine methyl ester with an aqueous medium containing (a) hydrogen chloride in an amount not more than ca. 2 mol., per liter of said aqueous medium, but not less than 1 mol., per mole of said of said mixture of .alpha.-L-aspartyl-L-phenylalanine methyl ester and .beta.-L-aspartyl-L-phenylalanine methyl ester, and (b) an inorganic chloride selected from the group consisting of NaCl, KCl, NH.sub.4 Cl, CaCl.sub.2, and ZnCl.sub.2 in an amount of at least ca. 50 g., per liter of said aqueous medium, to form crystals of .alpha.-L-aspartyl-L-phenylalanine methyl ester hydrochloride, andii) recovering the .alpha.-L-aspartyl-L-phenylalanine methyl ester hydrochloride crystals therefrom.

Abstract: The present invention is directed to a process for producing L-aspartyl-L-phenylalanine and/or L-aspartyl-L-phenylalanine diketopiperazine comprising contacting and reacting a culture, cell or a cell-treated product of a microorganism capable of hydrolyzing DKP into AP or capable of performing intramolecular condensation of AP into DKP with DKP and/or AP, in an aqueous medium.

Abstract: A process for recovering .alpha.-L-aspartyl-L-phenylalanine methyl ester from a solution containing various methyl ester or demethylated derivatives of .alpha.-L-aspartyl-L-phenylalanine methyl ester and chloride ions is disclosed. This process uses a reverse osmosis membrane having a specific chloride inhibition rate to desalt and concentrate a solution containing a specified ratio of .delta.-L-aspartyl-L-phenylalanine methyl ester to its derivatives until a specific weight ratio of organic chloride ion to the sum of .alpha.-L-aspartyl-L-phenylalanine methyl ester and its derivatives is obtained. This desalted and concentrated solution is then contacted with an aqueous solvent containing methanol and hydrochloride acid to recover high yields of .alpha.-L-aspartyl-L-phenylalanine methyl ester hydrochloride.

Abstract: N-formyl-.alpha.-L-aspartyl-L-phenylalanine methyl ester is obtained by reacting L-phenylalanine methyl ester with N-formyl-L-aspartic acid anhydride in a reaction solvent containing acetic acid or acetic acid and formic acid in a complete mixing type continuous reaction mode.

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: A process is described for the synthesis of N-protected-L-.alpha.-aspartyl-L-phenylalanine by both (a) the rection of an N-protected-L-aspartic anhydride and a R.sub.1 -L-phenylalanine, and (b) the reaction of an N-protected-L-aspartic anhydride and L-phenylalanine in an aqueous medium in the presence of R.sub.2, where R.sub.1 may be an alkali metal salt, alkaline earth metal salt, ammonium salt or organic amine salt, and R.sub.2 may be an ammonium salt or an alkali or alkaline earth metal salt of an inorganic or organic acid.

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: A process is described for the synthesis of N-protected-L-.alpha.-aspartyl-L-phenylalanine by both (a) the reaction of an N-protected-L-aspartic anhydride and a R.sub.1 -L-phenylalanine, and (b) the reaction of an N-protected-L-aspartic anhydride and L-phenylalanine in an aqueous medium in the presence of R.sub.2, where R.sub.1 may be an alkali metal salt, alkaline earth metal salt, ammonium salt or organic amine salt, and R.sub.2 may be an ammonium salt or an alkali or alkaline earth metal salt of an inorganic or organic acid.

Abstract: A method for converting .beta.-aspartylphenylalanine derivative (1) to .alpha.-aspartylphenylalanine derivatives (2) and (3), said derivatives having the following structures: ##STR1## which comprises: reacting said .beta.-aspartylphenylalanine derivative (1) at a temperature of from 0.degree. to 200.degree. C. for a time period of from 30 minutes to 80 hours, in a C.sub.1 to C.sub.4 alcohol solvent with or without stirring, wherein R and R' represent hydrogen or an alkyl group having from 1 to 4 carbon atoms.

Abstract: A process for producing N-formylaspartic anhydride, which comprises, grinding solid aspartic acid into fine particles; and then reacting said finely ground aspartic acid with formic acid and acetic anhydride.

Abstract: A process for producing L-aspartyl-L-phenylalanine alkyl or aryl esters wherein L-aspartic acid and L-phenylalanine which is esterified with an alkyl group having at least two carbon atoms, an aryl group or an aralkyl group, are contacted in an aqueous medium with particular microorganisms or enzyme fractions from these microorganisms and the condensed product crystallizes out due to insolubility in the aqueous medium.

Abstract: A method for optical resolution of a DL-amino acid comprising reacting the DL-amino acid with an optically active N-acyl aspartic acid in a solvent or mixture of solvents, and separating the resulting two diasteromeric salts by way of the difference between their solubilities in the solvent or mixture of solvents. The difference in solubility may be enhanced by cooling, concentration, addition of a solubility-decreasing organic solvent, pH adjustment or salting out.