| 摘要 |
<p>1-[3-(4-m-Chlorophenyl-1-piperazinyl)-propyl]-3,4-diethyl- DELTA 2-1,2,4- triazolin-5-one of the formula (I) <IMAGE> shows tranquillising properties in human therapy. (I) is prepared by cyclisation of 2-[3-(4-m-chlorophenyl-1-piperazinyl)-propyl]-4-ethyl-1-propionyl-semi carbazide (III) <IMAGE> or, which is chemically equivalent, by reacting N-[3-(4-m-chlorophenyl-1-piperazinyl)-propyl]-N'-propionylhydrazine with ethyl isocyanate <IMAGE> In fact, in the reaction between (II) and ethyl isocyanate, (III) is formed as an intermediate which can easily be isolated. The most convenient way of synthesising (III), which is not described in the literature, is precisely the method just described. (I) is also prepared by reacting 3-(4-m-chlorophenyl-1-piperazinyl)-propyl-hydrazine (IV) with an alkylpropionylcarbamate (V) such as, for example, propionylurethane. <IMAGE> In the formula (V), R is lower alkyl. Equimolar mixtures of the two reagents are heated for several hours in an inert solvent in the presence of a dehydrating agent.</p> |
