GB819681A - Improvements in and relating to quaternary ammonium compounds and the preparation thereof - Google Patents

Abstract

The invention comprises compounds of the formula <FORM:0819681/IV (b)/1> (wherein R1 is a hydrogen, bromine or chlorine atom, or a methyl or nitro group, R2 is a hydrogen, bromine or chlorine atom, or a methyl group, and A- is an anion equivalent of an organic acid) whose solubility in water is less than 1.00 per cent w/v at 20 DEG C., and the preparation thereof by reacting in aqueous solution a water-soluble salt of the cation with a water-soluble metallic salt (e.g. sodium salt) of the desired organic acid. Examples are given in which R1 is a hydrogen atom, methyl or nitro group, R2 is a hydrogen, bromine or chlorine atom, and A- is the anion of naphthalene-1- or -2-sulphonic acid, diphenyl-4-sulphonic acid, 1- or 2-naphthol-3 : 6-disulphonic acid, naphthalene-1 : 5- or -2 : 7-disulphonic acid, 1- or 2-naphthoic acid, 2-hydroxy-3-naphthoic acid, 2 : 21-dihydroxy-1 : 11 - dinaphthylmethan - 3 : 31 - dicarboxylic (embonic) acid or 4 : 41-dihydroxy diphenylmethane - 3 : 31 - dicarboxylic acid. The compounds of the invention are useful as veterinary remedies. N - Benzyl - N : N - dimethyl - N - 2 - (o - methylphenoxyethyl) ammonium chloride is made from 1 - dimethylamino - 2 - o - methylphenoxyethane and benzyl chloride. Similarly made is N - O - chlorobenzyl - N : N - dimethyl - N - 2 - phenoxyethylammonium chloride monohydrate.ALSO:An anthelmintic pharmaceutical composition contains a quarternary ammonium compound of the formula <FORM:0819681/VI/1> (wherein R1 is a hydrogen, bromine or chlorine atom, or a methyl or nitro group, R2 is a hydrogen, bromine or chlorine atom, or a methyl group, and A- is an anion equivalent of an organic acid) whose solubility in water is less than 1.00 per cent w/v at 20 DEG C., in admixture with a pharmaceutically inert excipient. Suitable salts, some of which are used in examples, are those in which A- is the anion of naphthalene-1- or -2-sulphonic acid, diphenyl-4-sulphonic acid, 1- or 2-naphthol-3 : 6-disulphonic acid, naphthalene-1 : 5- or -2 : 7-disulphonic acid, 1- or 2-naphthoic acid, 2-hydroxy-3 - naphthoic acid, 2 : 21 - dihydroxy - 1 : 11 - dinaphthylmethane - 3 : 31 - dicarboxylic (embonic) acid or 4 : 41-dihydroxydiphenylmethane-3 : 31-dicarboxylic acid. The compositions may take the form of tablets, a dispersible powder containing calcium silicate (wherein, if desired, the excipient is or includes a surface-active agent), a hard or soft gelatin capsule, a suspension in syrup, or an aqueous suspension containing, if desired, suitable suspending agents. Excipients which are exemplified include cetrimide and polyoxyethylene sorbitan mono-oleate. The sparingly soluble salts may also be used in admixture with more soluble salts of the same type of cation.