Abstract: Citalopram can be industrially and economically produced and at a high yield by reacting a compound of the following formula [VI] with 3-(dimethylamino)propyl chloride in the presence of at least one of N,N,N′,N′-tetramethylethylenediamine and 1,3-dimethyl-2-imidazolidinone and a condensing agent. The compound of the following formula [III], which is a key compound for the production of citalopram, can be easily produced by subjecting the compound of the following formula [II] to reduction and cyclization.
Abstract: Methods for producing anhydrous mirtazapine crystals that are either (1) substantially free of lower alcohol insolubles or (2) substantially free of residual solvent and have an average particle diameter of from 10 to 50 &mgr;m, are provided, and the resulting anhydrous mirtazapine crystals produced thereby, which are useful in pharmaceuticals.
Abstract: The present invention provides a production method of a 5-phthalancarbonitrile compound, which comprises the use of a novel compound of the formula [I]
wherein X is chlorine atom, bromine atom or iodine atom, as a key intermediate. The method of the present invention imposes small environmental burden (without use of a reagent imposing great burden on the environment, such as heavy metal, metal cyanide, thionyl chloride and the like) and is safe. The inventive method is based on a completely new strategy which is different from conventional production methods of 5-phthalancarbonitrile compound.
Abstract: Citalopram can be industrially and economically produced and at a high yield by reacting a compound of the following formula [VI] with 3-(dimethylamino)propyl chloride in the presence of at least one of N,N,N′,N′-tetramethylethylenediamine and 1,3-dimethyl-2-imidazolidinone and a condensing agent. The compound of the following formula [III], which is a key compound for the production of citalopram, can be easily produced by subjecting the compound of the following formula [II] to reduction and cyclization.
Abstract: A production method of hydrazine derivative having a group of the formula (II)
which comprises subjecting a hydrazone derivative having a group of the formula (I)
to catalytic reduction and deactivating the reduction catalyst contained in the reaction mixture thereof.
Abstract: A pyridinemethanol compound is an important intermediate for a mirtazapine which is useful as an antidepressant. The pyridinemethanol compound is obtained by reducing potassium pyridinecarboxylate represented by the formula (I):
with a metal hydride.
Abstract: The present invention provides a production method of a 5-phthalancarbonitrile compound, which comprises the use of a novel compound of the formula [I] 1
Abstract: A process for preparing tert-butyl 4′-methyl-2-biphenylcarboxylate characterized in that 4′-methyl-2-biphenylcarboxylic acid is reacted with isobutene in the presence of an acid catalyst. According to the present invention, tert-butyl 4′-methyl-2-biphenylcarboxylate having high quality can be conveniently and industrially advantageously prepared in a high yield under mild reaction conditions such as ambient temperatures without complicated procedures or any hazardous solvents.
Abstract: The present invention provides a method for producing a hydrazine derivative of the formula [2]:
wherein R1 is alkyl group having 1-12 carbon atoms and the like, R2 is alkyl group having 1-12 carbon atoms and the like, and Ar is phenylene group and the like, from a hydrazone derivative of the formula [1]
wherein R1, R2 and Ar are as defined above, in the presence of at least one base selected from the group consisting of an organic base and an inorganic base, and a metal hydrogenating catalyst. By this method, reduction proceeds selectively and a hydrogenolysis reaction (side reaction) can be suppressed.
Abstract: The present invention provides a crystalline or crystallized acid addition salt of Losartan useful for obtaining highly pure 2-n-butyl-4-chloro-1-[[2′-(1H-tetrazol-5-yl)[1,1′-biphenyl]-4-yl]methyl]-1H-imidazole-5-methanol (Losartan), and a purification method of Losartan that includes production of the crystalline or crystallized acid addition salt.
Abstract: The present invention is directed to a process for preparing a cyclopropane ring-cleaved purine derivative represented by the following formula:
comprising hydrogenating a purine derivative having a cyclopropane ring represented by the following formula:
Abstract: A process for preparing 2,6-dichloropurine including chlorinating 2-amino-6-chloropurine with a chlorine source in the presence of a diazotizating agent.
Abstract: A process for preparing a tert-alkyl carboxylic acid ester represented by the formula (III):
wherein R1 is an organic group; and each of R2 and R3 is independently an alkyl group having 1 to 4 carbon atoms, comprising reacting a carboxylic acid represented by the formula (I):
R1—COOH (I)
wherein R1 is as defined above, with a vinylidene compound represented by the formula (II):
wherein R2 and R3 are as defined above, in the presence of a phosphorus halide. The tert-alkyl carboxylic acid ester can be used as intermediates for pharmaceuticals such as antibiotics.
Abstract: An L-tartrate of a trans-(−)-4-(4-fluorophenyl)-3-hydroxymethylpiperidine compound, represented by the formula (I):
wherein R1 is hydrogen atom, a substituted or unsubstituted, linear or branched alkyl group having 1 to 6 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms. The L-tartrate of trans-(−)-4-(4-fluorophenyl)-3-hydroxymethylpiperidine compound can be suitably used as an intermediate for pharmaceuticals such as paroxetine which is useful, for example, as an antidepressant.
Abstract: The present invention provides a production method of a 5-phthalancarbonitrile compound, which comprises the use of a novel compound of the formula [I]
wherein X is chlorine atom, bromine atom or iodine atom, as a key intermediate; intermediate; and the process of preparing intermediates.
Abstract: A series of compounds capable of deriving an intermediate for the production of compound (A) of the following formula,
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)phenylmethylidene]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 series of compounds capable of deriving an intermediate for the production of a compound (A) of the following formula,
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)phenylmethylidene]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.