Patent GB-855231-A (GB)
Title: Improvements in or relating to heterocyclic compounds
Inventor: WRAGG WILLIAM ROBERT
IPC: C07D221/12
Filed: 1956-07-13
Abstract: The invention comprises compounds of the formula: <FORM:0855231/IV(b)/1> (wherein R1 is an amino group or a phenyldiazoamino group containing an amido, sulphonamido, carboxy, nitro, dialkylamino or dialkylaminoethoxycarbonyl group or a halogen atom, R2 is a hydrogen atom, an amino group or a phenyldiazoamino group containing a substituent as defined above, such that at least one of R1 and R2 is a substituted phenyldiazoamino group, R3 is a phenyl group which may contain an amino or nitro group or a substituted phenyldiazoamino group as defined above as a substituent, R4 is an alkyl group and Y is an anion) and their preparation by coupling a phenanthridinium salt of the formula: <FORM:0855231/IV(b)/2> (wherein R5 is an amino group and R6 is hydrogen or an amino group) with the appropriate molecular proportion of a diazonium salt of the appropriate substituted aniline (giving, when R5 and R6 are both amino groups and only one of them is coupled, a mixture of isomers), or by diazotizing a salt of formula II and coupling it with the appropriate substituted aniline.  When in the final product the group R3 is required to be a substituted phenyldiazoaminophenyl group, the products may be obtained by commencing with the appropriate intermediate wherein R3 is a p-aminophenyl group.  In examples (1) m-aminobenzene-sulphonamide is diazotized and added to an aqueous solution of 2 : 7-diamino-10-ethyl-9-phenyl-phenanthridinium chloride to give, on working up, a mixture of two products, viz. 7(2)-amino-10-ethyl-9-phenyl-2(7)-(m-sulphamoylphenyldiazoamino) -pehnanthridinium chloride and 2(7)-amino-10-ethyl-9-phenyl-7(2)-(m-sulphamoylphenyldiazoamino) -phenanthridinium chloride, separated by exhaustive crystallization from methanol; (2) to (10) by similar processes, other phenanthridinium salts containing in place of the m-sulphamoyl group of (1) the following groups, m-carbamoyl, p-carboxy, p-sulphamoyl, p-carbamoyl, p-(2-diethylaminoethoxycarbonyl), p-dimethylamino, m-nitro, p-chloro and o-chloro, are prepared, in some cases only one isomer and in others both being isolated; (11) 2 : 7-diamino-10-ethyl-9-phenylphenanthridinium chloride is tetrazotized and mixed with a hydrochloric acid solution of 4-chloroaniline to give, on working up, 2 : 7-di-(4-chlorophenyldiazoamino)-10-ethyl-9-phenyl-phenanthridinium p chloride; (12) 4-chloroaniline is diazotized and added to an aqueous solution of 7-amino-9-(4-aminophenyl)-10-methylphenanthridinium isethionate to give, on working up, a mixture of 7-amino-9-(4-chlorophenyl-diazoaminophenyl) -10-methylphenanthridinium chloride and 7-(4-chlorophenyldiazoamino)-9-(4-aminophenyl) -10-methylphenanthridinium chloride; and (13) p-aminobenzamide is diazotized and added to an aqueous solution of 2 : 7-diamino-10-methyl-9-(4-nitrophenyl)-phenanthridinium isethionate (prepared from the corresponding chloride via the hydroxide) to give, on working up, the mixed isomers 2(7)-amino-7(2)-(p-carbamoylphenyldiazoamino) - 10 - methyl - 9 - (4 - nitrophenyl)-phenanthridinium chloride.  In the Provisional Specification one of R1 and R2 is defined as a substituted phenyldiazoamino group and the other as a substituted phenyldiazoamino group, an amino group or a hydrogen atom, and R3 is defined as an alkyl, aryl or substituted aryl group.  Specification 834,231 is referred to.