Abstract: A series of compounds capable of deriving an intermediate for the production of a compound (A) of the following formula, ##STR1## which is an anti-HIV drug, and a production method thereof. To be specific, 4-(pyridin-2-yl)benzaldehyde hydrazone, a production method of this compound, and a production method from this compound to N-(tert-butoxycarbonyl)-N'-[4-(pyridin-2-yl)phenylmethyhidene]hydrazine. In addition, a salt of 2-(4-bromomethylphenyl)pyridine, 2-(4-dibromomethylphenyl)pyridine and a salt thereof, production methods of these compounds, and production methods to derive 4-(pyridin-2-yl)benzaldehyde which is a production intermediate for 4-(pyridin-2-yl)benzaldehyde hydrazone from these compounds.

Abstract: A method of producing a 2-(p-alkylphenyl)pyridine compound economically, easily and industrially, which comprises adding manganese dioxide and trimethylchlorosilane, or adding manganese chloride to an organic ether solvent, and reacting p-alkylphenylmagnesium halide and 2-halopyridine in the obtained organic ether solvent.

Abstract: A method for producing alkylated cyanoacetylurea from an easily obtainable starting material. An industrially available cyanoacetylurea and a carbonyl compound are reacted in a polar solvent under reducing conditions to alkylate cyanoacetylurea In addition, a reaction of cyanoacetylurea and acetone under reducing conditions affords isopropylation of cyanoacetylurea.

Abstract: A method for producing potassium oxonate which comprises dissolving allantoin in an aqueous potassium hydroxide solution or an aqueous potassium carbonate solution, and oxidizing said allantoin with an alkali metal hypohalogenite in the presence of potassium iodide is provided and, according to the method, potassium oxonate can be efficiently produced without requiring a manganese compound which may entail environmental pollution.

Abstract: A process for preparing a 2-cyanobiphenyl compound represented by the formula (II): ##STR1## wherein R.sup.1 is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or hydrogen atom, from a phenylmagnesium chloride compound represented by the formula (I): ##STR2## wherein R.sup.1 is as defined above. According to the process, a 2-cyanobiphenyl compound represented by the formula (II) can be economically, simply, industrially and advantageously prepared.

Abstract: The process for preparing 2-amino-6-iodopurine including the steps of suspending at least one chloropurine compound selected from 2-formylamino-6-chloropurine, 2-formylamino-6-chloropurine acetate and 2-amino-6-chloropurine in a solution comprising aqueous hydriodic acid and an alkyl ketone having 3 to 7 carbon atoms; and stirring the resulting suspension at 0.degree. to 50.degree. C. According to the process of the present invention, 2-amino-6-iodopurine can be simply, industrially, and advantageously prepared.

Abstract: A piperidine derivative, which can be used as an intermediate for pharmaceuticals such as paroxetine useful as antidepressants, represented by the general formula (I): ##STR1## wherein R.sup.1 is hydrogen atom, benzyloxycarbonyl group or tert-butoxycarbonyl group; R.sup.2 is hydroxymethyl group, an alkylsulfonyloxymethyl group having an alkyl moiety of 1 to 2 carbon atoms, phenylsulfonyloxymethyl group which may have methyl group at the 4-position, (3,4-methylenedioxyphenyl)oxymethyl group, carboxyl group or --CO.sub.2 R.sup.7 group in which R.sup.7 is an alkyl group having 1 to 5 carbon atoms, and Z is methylene group or carbonyl group.

Abstract: A method for producing 5-isopropyluracil at a high yield in a short time, wherein N-(2-cyano-3-methylbutanoyl)urea is reduced in a 10-15% aqueous sulfuric acid solution in the presence of palladium carbon at 30-45.degree. C., heated for ring closure reaction and added to a 50-70% aqueous sulfuric acid solution to give 5-isopropyluracil having a high purity.

Abstract: Process for preparing 1,3-disubstituted urea of the formula: ##STR1## wherein R.sup.5 is the same as or different from R.sup.6, and each of R.sup.5 and R.sup.6 is independently linear or branched, alkyl of 1-20 carbon atoms, alkenyl group having 2 to 20 carbon atoms or alkynyl group having 2 to 20 carbon atoms, which may have phenoxy, alkoxy of 1-13 carbon atoms, monocycloalkyl of 3-8 carbon atoms, bicycloalkyl of 6-12 carbon atoms, aryl of 6-13 carbon atoms, furyl, pyridyl, or aralkyl of 7-20 carbon atoms, comprising reacting cyclic carbonic acid ester with an amine using alkali metal alkoxide or trialkylamine as base, in safety and high yield.

Abstract: Process for preparing 4'-methyl-2-cyanobiphenyl, comprising, catalytically hydrogenating at least one brominated cyanobiphenyl compound selected from 4'-dibromomethyl-2-cyanobiphenyl and 4'-bromomethyl-2-cyanobiphenyl; and process for regenerating 4'-methyl-2-cyanobiphenyl, comprising, catalytically hydrogenating at least one brominated cyanobiphenyl compound selected from 4'-dibromomethyl-2-cyanobiphenyl and 4'-bromomethyl-2-cyanobiphenyl, contained in a filtrate prepared by brominating 4'-methyl-2-cyanobiphenyl in a solvent; crystallizing 4'-bromomethyl-2-cyanobiphenyl from the resulting reaction mixture; and removing the resulting crystals from the reaction mixture by filtration. 4'-Methyl-2-cyanobiphenyl can be used as starting materials for 4'-bromomethyl-2-cyanobiphenyl.

Abstract: The present invention is directed to a method for preparing 2-amino-6-chloropurine having a double cone-like crystal form, comprising the steps of:(A) suspending 2-amino-6-chloropurine having an acicular or irregular-shaped crystal form in a liquid consisting essentially of water having a pH of from 3 to 10; and(B) heating the resulting suspension at a temperature of from 70.degree. to 100.degree. C. to complete the double cone-like crystal form conversion.

Abstract: A method for producing 4'-bromomethyl-2-cyanobiphenyl by the step of treating 4'-methyl-2-cyanobiphenyl with Br.sub.2 in a halogenated hydrocarbon solvent or an alkane solvent having 5 to 7 carbon atoms.

Abstract: A method for producing 1,4-dihydroxy-2-naphthoic acid which comprises the steps of: subjecting 1,4-dihydroxynaphthalene into an alkali metal salt formation reaction in an organic medium capable of dissolving 1,4-dihydroxynaphthalene using an alkali metal alcoholate; and subjecting the salt formation reaction mixture to carboxylation using carbon dioxide gas.

Abstract: A method for producing an alkyl 3-phthalidylideneacetate has the step of treating phthalic anhydride with a monoalkyl malonate or a salt thereof having the following formula:MOCO--CH.sub.2 --COOR,wherein M represents a hydrogen atom, K, Na, Li, or NH.sub.4, and R represents a lower alkyl group having 1 to 5 carbon atoms. By using the above method, the desired alkyl 3-phthalidylideneacetate can be obtained at a high yield.

Abstract: The present invention is directed to a method for production of a 2-amino-6-halogenopurine, a novel synthesis intermediate therefor and a method for production of said synthesis intermediate. The desired 2-amino-6-halogenopurine is an intermediate for the production of the compounds useful as antiviral agents, and by using the compound of the present invention as a starting material, the 2-amino-6-halogenopurine can be produced in high yield.

Abstract: The present invention is directed to a method for production of a 2-amino-6-halogenopurine, a novel synthesis intermediate therefor and a method for production of said synthesis intermediate. The desired 2-amino-6-halogenopurine is an intermediate for the production of compounds useful as an antiviral agent, and by using the compound of the present invention as a starting material, the 2-amino-6-halogenopurine can be produced in high yield.

Abstract: The present invention is directed to a method for production of a 2-amino-6-halogenopurine, a novel synthesis intermediate therefor and a method for production of said synthesis intermediate. The desired 2-amino-6-halogenopurine is an intermediate for the production of compounds useful as antiviral agents, and by using the compound of the present invention as a starting material, the 2-amino-6-halogenopurine can be produced in high yield.

Abstract: A method for producing 2,6-dihydroxybenzoic acid, which comprises heating an aqueous solution which contains a mixture of 2,6-dihydroxybenzoic acid and 2,4-dihydroxybenzoic acid and has a pH value of 4 or more, to selectively decompose 2,4-dihydroxybenzoic acid, and separating 2,6-dihydroxybenzoic acid from the decomposition reaction mixture.

Abstract: A process for producing 2-methyl-1,3-cyclohexanedione which comprises subjecting 1,3-cyclohexanedione, formaldehyde and a dialkylamine to Mannich reaction to obtain a 2-dialkylaminomethyl-1,3-cyclohexanedione, and subjecting the 2-dialkylaminomethyl to hydrogenolysis, and a process for producing 2-methylresorcinol which comprises aromatizing 2-methyl-1,3-cyclohexanedione obtained. According to these processes, it is possible to produce high-purity 2-methylresorcinol and 2-methyl-1,3-cyclohexanedione commercially easily and advantageously.