Abstract:
PURPOSE: Provided is a method for manufacturing a 5-(4-substituted-£1,2,5|thiadiazol-3-il)-3-methyl-1,2,3,4-tetrahydropyrimidine derivative which is effective on improving memory and treating Alzheimer's disease. CONSTITUTION: A 5-(4-substituted-£1,2,5|thiadiazol-3-il)-3-methyl-1,2,3,4-tetrahydropyrimidine derivative represented by the formula (1) is manufactured by the following steps of: i) reacting 5-pyrimidine carboxylaldehyde of the formula (2) with KCN/HOAc to synthesize hydroxy-pyrimidine-5-il-acetonitrile of the formula (3); ii) reacting hydroxy-pyrimidine-5-il-acetonitrile of the formula (3) with ammonium chloride and ammonium hydroxide to obtain amino-pyrimidine-5-il-acetonitrile of the formula (4) and reacting again amino-pyrimidine-5-il-acetonitrile with S2CL2 to obtain 5-(4-chloro-£1,2,5|thiadiazol-3-il)pyrimidine of the formula (5); iii) reacting 5-(4-chloro-£1,2,5|thiadiazol-3-il)pyrimidine with NaSH and alkylhalide to obtain a compound of the formula (6a); iv) reacting the compound of the formula (6a) with CH3L or methylfluoromethansulfonate at room temperature to obtain 5-(4-substituted sulfanil-£1,2,5|thiadiazol-3-il)-3-methylpyrimidium iodide of the formula (7a); and v) reducing 5-(4-substituted sulfanil-£1,2,5|thiadiazol-3-il)-3-methylpyrimidium iodide with NaBH4 to obtain a 5-(4-substituted-£1,2,5|thiadiazol-3-il)-3-methyl-1,2,3,4-tetrahydropyrimidine derivative. In the formula (1), X is oxygen atom or sulfur atom; R is hydrogen atom, low alkyl group having 1-5 carbon, propargyl group, benzil group, 4-methylbenzil group, or 4-chlorobenzil group.
Abstract:
PURPOSE: Title derivatives are prepared which has a good therapeutic activity of dys-mnesia and senile athymia. CONSTITUTION: Title compounds (formula 1; R is -H, -CH3, -CH2CH3, -CH2(CH2)3CH3, -CH2CH=CH2, etc.) and their pharmaceutical salt are prepared. Thus, 1.24 g of hydroxylamine hydrochloride is dissolved in water, and controlled to pH 7 by NaHCO3 saturated aqueous solution. The solution is refluxed for 2 hours in a mixed solution of 5-acetylpyrimidine and 50 ml of benzene using Dean-Stark column. Obtained solution is concentrated under reduced pressure to give 1.28 g of 1-pyrimidin-5-yl-(E)-ethanone oxime(yield 78 %).