Loprazolam (1) is a tricyclic benzodiazepine containing a new butazadiene moiety, which has not been investigated by polarography up to now. 1 is reduced in three waves at a DME over the whole pH-region. In BRP (pH 2-9) 10 electrons are consumed in this process. The first step is suitable for the determination of 1 in Loprazolam tablets containing 1 or 2 mg. These tablets are on the pharmaceutical market in several European countries. The mechanism of the electrode process will be reported in the communication XXXIV.

Loprazolam (1) wird an der Quecksilbertmpfelektrode in sauren Puffem (pH 2.8) in h i Stufen reduzien (DCT). Die e m Stufe (A) entspricht der Reduktion seiner N02-Gruppe zur Hydroxylaminmtufe (4 €3). die zweite Stufe (B)der Reduktion der X = N --Doppelbindung (5.6) (2 €3), und die Stufe bei dem negativsten Potential (C) ist der Reduktion der Butazadiengruppierung zuzuordnen (4 8). Erst 8).The first wave (A) cornsponds to the reduction of its NO2-group to the corresponding hydroxylamine (4 43). the second step (B) to the reduction of the X=N-double bond (5.6) (2 e) and the wave C at the most negative potential has to be ascribed to the reduction of the butazadiene grouping (4 €3). Only in strongly acid buffers (pH < 2.8) the pmtonated hydroxylamino group is reduced to R-NH2; consequently an overall 12 8 consumption has been observed here for the sum of all three waves.