1177093-13-8Relevant articles and documents
AN IMPROVED PROCESS FOR THE PREPARATION OF ANTIHISTAMINIC DRUGS VIA A NOVEL CARBAMATE INTERMEDIATE
-
, (2012/08/08)
The present invention relates to a novel racemic or optically active carbamate intermediate of formula (IV A). This novel racemic or optically active carbamate intermediate of formula (IV A) can be used to prepare drugs having antihistaminic activity such as cetirizine (IA), meclizine (IB), chlorcyclizine (IC), clocinizine (ID), buclizine (IE) and enantiomers thereof such as levocetirizine (I). Further, disclosed herein is an improved process for the preparation of levocetirizine via a novel optically active intermediate i.e. compound of formula (IV). Also, disclosed herein is a novel process for the preparation of compound (II) and for crystallization of its salt.
NOVEL WATER BASED PROCESS FOR THE PREPARATION OF SUBSTITUTED DIPHENYLMETHYL PIPERAZINES
-
Page/Page column 8-9, (2011/08/03)
The present invention relates to a novel water based process for the preparation of substituted diphenylmethyl piperazines of Formula I and pharmaceutically acceptable salts wherein X1 and X2 represent independently a hydrogen, a halogen, a straight or branched chain lower alkyl, alkoxy or a hydroxyl radical and R is selected from groups such as acyl, alkyl, alkenyl, aralalkyl, aralalkenyl aralkyl, and aralalkenyl or aralkenyl hydroxyalkyl, aryloxyalkyl, alkoxyalkyl, aminoalkyl or its derivative comprising, reacting a compound of Formula II, with a compound of formula R—X where R is as defined above and X is suitable leaving group which includes halides, but not limiting use of other leaving groups such as tosylate, mesylate and activated acid groups such as acyl halide, anhydrides, mixed anhydrides etc. using water as a solvent, in presence of a catalyst and a base, at 25-100° C.;