Patent GB-551207-A (GB)
Title: Improvements in and relating to the manufacture of sulphonamido compounds
IPC: C07D239/42
Filed: 1941-04-29
Abstract: 551,207. Aryl sulphenamides and sulphonamides. MANCHESTER OXIDE CO., Ltd., BANN, B., KRUG, P., WHEELER, D. E., TAYLOR, W., and GLADDING, G. April 29, 1941, Nos. 7286/42, 7287/42, [both divided out of 553,269], and 7079/42. [Class 2 (iii)] Benzenesulphonamidopyrimidines and p-substituted derivatives thereof are prepared by the oxidation of the corresponding sulphenamides, e.g. with alkali or alkaline earth permanganate or hypochlorite. The sulphenamides may be obtained by treating a diphenyldisulphide with chlorine in a non-aqueous medium and reacting the resulting sulphenyl chloride with an aminopyrimidine; the diphenyldisulphides may be prepared by heating with caustic alkali a thiocyanobenzene obtainable as described in Specifications 513,473 and 514,203. The sulphenamides may also be prepared by reacting a benzenesulphenyl ester or a benzenesulphenamide with an aminopyrimidine. The substituent in the p-position is preferably a halogen atom or a nitrogencontaining group convertible into an amino group, e.g. an acylamino or nitro group, and the products may be converted into the amino compounds which are useful therapeutically. According to the examples, (1) 2-benzenesulphonamido-4 : 6-dimethylpyrimidine is prepared by treating benzenesulphenyl chloride, obtained by chlorinating diphenyldisulphide in chloroform, with 2-amino-4 : 6-dimethvlpyrimidine and oxidizing the product with aqueous potassium permanganate ; (2) 2-(41- nitrobenzenesulphonamido)-4 : 6-dimethylpyrimidine is obtained by chlorinating 4 : 4<SP>1</SP>-dinitrodiphenyldisulphide in chloroform, converting the resulting p-nitrobenzenesulphenyl chloride into p-nitrobenzenesulphenic acid ethyl ester by treatment with sodium ethoxide, re-acting it with 2-amino-4 : 6-dimethylpyrimidine and oxidizing the sulphenamido product with potassium permanganate; (3) 2-(41-aminobenzenesulphonamido)-pyrimidine results when p-nitrobenzenesulphenyl chloride is .treated with 2-aminopyrimidine and the sulphenamido product oxidized with potassium permanganate to the corresponding sulphonamide which is then reduced with iron and hydrochloric acid ; by using 2-amino-4 : 6-dimethylpyrimidine in this process, 2-(4<SP>1</SP>-aminobenzenesulphonamido)- 4 : 6-dimethylpyrimidine is obtained; calcium permanganate or sodium hypochlorite solution may be employed in place of potassium permanganate ; (4) 2-(4<SP>1</SP>-nitrobenzenesulphonamido)-4: 6-dimethylpyrimidine is also obtained by heating p-nitrobenzenesulphenamide with 2-amino-4 : 6-dimethylpyrimidine in benzene and oxidizing the sulphenamido-pyrimidine so formed ; (5) 2-(4<SP>1</SP>-aminobenzenesulphonamido)- 4 : 6-dimethylpyrimidine is prepared by treating p-acetylaminobenzenesulphenyl chloride, obtained by chlorinating 4 : 4<SP>1</SP>-diacetylaminodiphenyldisulphide in chloroform, with 2-amino- 4 : 6-dimethylpyrimidine, oxidizing the resulting sulphenamide with potassium permanganate and hydrolysing the product; (6) 2-(41-chlorobenzenesulphonamido)-4 : 6-dimethylpyrimidine is prepared by chlorinating 4 : 4<SP>1</SP>-dichlorodiphenyldisulphide in chloroform, reacting the resulting p-chlorobenzenesulphenyl chloride with 2-amino-4: 6-dimethylpyrimidine, and oxidizing the sulphenamide formed with potassium - permanganate ; the p-chloro group may be converted into amino by treatment with ammonia. Specification 379,683 also is referred to. The first Provisional Specification refers. to the production of the naphthyl compounds.