134 BACTERIOLOGICAL CHEMISTRY 



substituents on the two nitrogen atoms mentioned above. 

 Succinyl sulphathiazole, sulphasuxidine, 



N— CH 



COOH.CH2-CH2.CO.NH/' \sO2.NH— C CH, 



S 



is one of the most useful, especially for intestinal infections 

 such as dysentery because it is poorly absorbed from the 

 gut and breaks down slowly with liberation of sulpha- 

 thiazole. Uleron, 



NH2<^ ^S02NH.<^ ^SOa.N(CH3)2, 



is active against staphylococci. 



Tuberculous infections in guinea-pigs have been 

 successfully treated with promin, di-aminodiphenyl- 

 sulphone di glucose sulphonate, 



NnH. CH. (CHOH)4.CH20H 

 SOjNa 

 .NH. CH.(CHOH)4.CHaOH 

 SOgNa 



which is also active against tubercle bacilli in vitro. 

 Unfortunately it is fairly toxic to man, producing 

 hsemolytic anaemia. The related drug diasone, diamino- 

 diphenylsulphone disodium formaldehyde sulphoxylate 



/\ / 



NH.CHa.S02Na 



S02<^ -^HaO, is less toxic and has 



. ^NH.CHg.SOaNa 



similar curative effect on guinea-pig tuberculosis. It will 

 also cure hsemolytic streptococcal infections and pneumo- 

 coccal infections in mice. 



The Mode of Action of Chemotherapeutic Substances. — 

 The earliest theory of chemotherapeutic action is that 



