| 摘要 |
PURPOSE:To obtain the titled compound which is an intermediate for synthesizing medicines in high selectivity without using expensive raw materials nor forming by-products, by reacting a 1-amidino-4-formylpiperazine with a 1,1,3,3- tetraalkoxypropane as raw materials, and hydrolyzing the reaction product. CONSTITUTION:A 1-amidino-4-formylpiperazine expressed by formula I (R<1> and R<2> are H or lower alkyl) or a mineral acid salt thereof (specific example; 1-amidino-2-methyl-4-formylpiperazine, etc.) is reacted with a 1,1,3,3- tetraalkoxypropane expressed by formula II (R<3>-R<6> are lower alkyl) in a molar amount within preferably equimolar-2 times range based on the compound expressed by formula I at 0-30 deg.C, perferably in a mineral acid and further, as necessary, an adequate amount of a solvent and the resultant product is then hydrolyzed with an alkali to afford the aimed compound expressed by formula III. The molar amount of the mineral acid to be used is preferably within equimolar-5 times range. |
