| 摘要 |
<p>PURPOSE:To readily obtain the titled substance useful as an anesthetic agent, analgesic agent, antitussive agent, etc., in good yield, by reacting an aldoxime with a disubstituted cyanamide. CONSTITUTION:An aldoxime expressed by formula I (R<1> is alkyl, aryl, etc.) is reacted with a disubstituted cyanamide expressed by formula II (R<2> and R<3> are alkyl, aryl, etc., or may together link at the terminals thereof), as neces sary, in an inert organic solvent, e.g. THF, benzene, etc., at 50-150 deg.C to afford a 5-amino-3-substituted 1,2,4-oxadiazole expressed by formula III and 5-(N,N- disubstituted guanidino)-3-substituted 1,2,4-oxadiazole (novel substance) expressed by formula IV. In order to mainly obtain the compound expressed by formula III, the compounds expressed by formulas I and II are reacted at <=1:1 molar ratio in a short time. In order to mainly obtain t he compound expressed by formula IV, the reaction is carried out at >=1:2 above-mentioned molar ratio of the compounds expressed by formula I to II under a high pressure for a long time.</p> |
