A process for production of 2-pyrazolin-5-ones having the formula (I): ##STR1## which comprises cyclizing hydrazone derivatives having the formula (II): ##STR2## in the presence of a base; wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represents a specific group; compounds having the formula (I) as well as compounds having the formula (II) and a process for production thereof.
生产具有
化学式(I)的2-
吡唑啉-5-酮的方法:在碱存在下,使具有
化学式(II)的腙酮衍
生物环化;其中R.sup.1、R.sup.2、R.sup.3和R.sup.4分别代表特定基团;具有
化学式(I)的化合物以及具有
化学式(II)的化合物及其生产方法。