GB1324687A - 3-amino-delta2-pyrazoline derivatives and process for the preparation thereof - Google Patents

Abstract

1324687 Substituted pyrazolines CHINOIN GYOGYSZER - ES VEGYESZETI TERMEKEK GYARA RT 6 Aug 1970 [7 Aug 1969] 38061/70 Heading C2C [Also in Division G2] Compounds having one of the Formulae I (wherein R represents a straight or branched chain alkyl group or a cycloalkyl group the said groups being optionally substituted by one or more halogen atoms or by one or more amino, alkylamino, dialkylamino, nitro, hydroxy or aryl groups, or represents an aralkyl group (the alkyl portion of which contains 1 to 5 carbon atoms) and the aryl portion of which may be optionally substituted by one or more halogen atoms or by one or more nitro, alkyl, alkoxy, amino, alkylamino, or dialkylamino groups or represents an aryl group which may be substituted by one or more halogen, nitro, alkyl, alkoxy, amino, alkylamino and dialkylamino groups (aryl also includes heteroaryl); R<SP>1</SP> and R<SP>2</SP>, which may be the same or different, each represents a hydrogen atom or an alkyl group optionally substituted by one or more halogen atoms or by one or more amino, alkylamino, dialkylamino, nitro, hydroxy or aryl groups or an aryl group optionally substituted by one or more halogen atoms or by one or more nitro, alkyl, alkoxy, amino, alkylamino and dialkylamino groups; and R<SP>4</SP> represents a hydrogen atom or the acyl radical of an organic carboxylic acid) and salts thereof are prepared either (a) by reaction of a compound of Formula II (wherein R, R<SP>1</SP> and R<SP>2</SP> are as herein defined and R<SP>3</SP> represents an alkyl group optionally substituted by one or more halogen atoms or by one or more amino, alkylamino, dialkylamino, nitro, hydroxy or aryl groups or represents an optionally substituted aryl group (as hereinbefore defined) and R<SP>5</SP> represents an acyl group) or a salt thereof with a base, and if desired deacylating a compound of Formula I (wherein R<SP>4</SP> represents an acyl group) thus obtained whereby a compound of Formula I (wherein R<SP>4</SP> represents a hydrogen atom) is obtained; and/or if desired converting the compound of Formula I thus obtained into a salt thereof or converting the salt of the compound of Formula I thus obtained into the compound of Formula I or (b) by reacting a compound of Formula III or a salt thereof with an acylating agent or with an ester of formula R<SP>6</SP>OR<SP>7</SP> (wherein R<SP>6</SP> represents an acyl radical of an organic carboxylic acid and R<SP>7</SP> represents an alkyl group) and if desired N-acylating the compound of Formula I (wherein R<SP>4</SP> represents a hydrogen atom) thus obtained or if desired deacylating a compound of Formula I (wherein R<SP>4</SP> represents an acyl group) thus obtained whereby a compound of Formula I (wherein R<SP>4</SP> represents a hydrogen atom) is obtained; and/or if desired converting the compound of Formula I thus obtained into a salt thereof or converting the salt of the compound of Formula I thus obtained into the compound of Formula I. The compounds, with the exception of those wherein R is aryl, are novel. Intermediates of Formula II above are prepared from compounds of Formula III above wherein R 5 is H by ring closure. Intermediates of Formula III above are prepared by reaction of the required nitrile or an N-acyl derivative thereof with hydroxylamine and optionally acylating the product. Pharmaceutical compositions in conventional forms for oral or parenteral administration having central nervous system and antispasmodic activities comprise an above novel compound and a carrier or excipient.