Patent GB-1416459-A (GB)
Title: 2-benzoyl-3-amino-pyridines
IPC: C07D213/57
Filed: 1973-05-10
Abstract: 1416459 2 - Benzoyl - 3 - aminopyridines DEUTSCHE GOLDUND SILBER-SCHEIDEANSTALT 10 May 1973 [10 May 1972] 22298/73 Heading C2C Novel compounds of formula in which R<SP>1</SP> is a halogen atom; R<SP>2</SP> and R<SP>3</SP>, which may be the same or different, each represent a hydrogen atom, a halogen atom, a trifluoromethyl group, a hydroxy group, a cyano group, a low molecular weight C 1-6  alkyl group or a low molecular weight C 1-6  alkoxy group; R<SP>4</SP> is a hydrogen atom or a low molecular weight C 1-6  alkyl group and R<SP>5</SP> is a hydrogen atom, a low molecular weight C 1-6  alkyl group, a benzoyl group, a substituted benzoyl group, a low molecular weight carbalkoxy group or a group of the formula in which A represents an oxygen or a sulphur atom, an imino group or a low molecular weight C 1-6  alkylimino group, and R<SP>6</SP> represents a low molecular weight alkyl group with 1 to 7 carbon atoms, an alkyl group with 1 to 7 carbon atoms substituted one to three times by a halogen atom, a low molecular weight alkenyl group with 2 to 7 carbon atoms, a hydroxymethyl group, a carboxymethyl group, a carbalkoxymethyl group with 3 to 7 carbon atoms, an aminoalkyl group with 1 to 7 carbon atoms or an alkylamino alkyl group with a total of 2 to 13 carbon atoms, in which case a hydroxy group or a primary or secondary amino group can also be substituted by an alkanoyl group with 2 to 8 carbon atoms, a carbalkoxy group with 2 to 6 carbon atoms, a carbophenoxy group or a carbobenzyloxy group, and their salts are prepared by (a) reacting a compound of general Formula I, in which R<SP>4</SP> represents a hydrogen atom and R<SP>5</SP> represents a hydrogen atom or a low molecular weight alkyl group whilst R<SP>1</SP> to R<SP>3</SP> are as defined above, with a compound corresponding to the formula in which A and R<SP>6</SP> are as defined above and E is a halogen atom, especially chlorine or bromine, a hydroxy group or an acylated hydroxy group, or with an aliphatic lactone containing 3 to 8 carbon atoms; or (b) converting the radical R<SP>4</SP> and/or R<SP>5</SP> in a compound of general Formula I, in which R<SP>4</SP> and R<SP>6</SP> are as defined above, but in which R<SP>5</SP> can in addition also represent any other acyl group of the kind normally used in peptide chemistry, into another meaning corresponding to Formula I by alkylation, acylation, hydrolysis, catalytic hydrogenation or by reaction with phosphorus pentasulphide or ammonia or a low molecular weight monoalkylamine with 1 to 6 carbon atoms; or (c) by reducing the nitro group in compounds corresponding to the formula  in which R<SP>1</SP>, R<SP>2</SP> and R<SP>3</SP> are as defined above, into an amino group and optionally alkylating the amino group formed by low molecular weight C 1-6  alkyl radicals and/or acylating it with a compound corresponding to the Formula II above in which the symbols E, A and R<SP>6</SP> are as defined above, or with an aliphatic lactone containing 3 to 8 carbon atoms. 2 - [α - (Cyano) - o - chlorobenzyl] - 3 - nitro - 6- chloropyridine is prepared by reacting NaH with o-chlorobenzylcyanide and with 2,6-dichloro-3-nitropyridine. 2 - Benzoyl - 3 - nitro - 6 - chloropyridine is prepared by reaction of KOH 2 H 2 O with 2 - (α - cyanobenzyl) - 3 - nitro - 6 - chloropyridine which has been prepared by reaction of NaH 2,6-dichloro-3-nitropyridine and benzylcyanide or 2-benzoyl-3-nitro-6-hydroxypyridine prepared as a by-product in the oxylation may be halogenated. Pharmaceutical compositions in conventional forms for oral, perlingual, rectal, topical or parenteral administration having antiphlogistic, sedative and angiolytic properties comprise an above novel compound and a carrier or diluent.