Antiseptic Action of Substances of the Chloramine Group. 23 5 



(4) Substitution in the nucleus of aromatic chloramines by CI, Br, I, CH3, 

 C 2 H 5 , or N0 2 groups does not lead to any very great increase in germicidal 

 activity. More commonly there is a moderate diminution. 



(5) The chloramine derivatives of naphthalene and otber dicyclic com- 

 pounds of the sulphochloramide type closely resemble the simpler aromatic 

 chloramines in germicidal action. 



(6) The few bromamines examined show a slightly lower germicidal action 

 than the corresponding chloramines. But the sodium sulphobromamides 

 are much more active than sodium hypobromite. It is significant that they 

 react much more readily with amino-acids and proteins than does sodium 

 hypobromite. 



(7) Derivatives of proteins prepared by the action of sodium hypochlorite 

 and containing (NCI) groups are strongly germicidal. Blood serum inhibits 

 their germicidal action to much the same extent as it does with sodium 

 hypochlorite or the aromatic chloramines. 



Mode of Action of Chloramines and Related Substances. 



Although it is obvious that nothing more than an incomplete explanation 

 is at present feasible, it is possible to discuss some of the factors regulating 

 the germicidal action of the chloramines. 



Chloramines and bromamines are usually more actively germicidal — or at 

 least will kill organisms at a lower molecular concentration — than the 

 •corresponding hypochlorite or hypobromite. Hence they cannot be regarded 

 .as the biochemical equivalents of the latter substances. It appears as if 

 .their germicidal qualities were due to the properties of the complex chlor- 

 .amine or bromamine molecule as a whole, apart from the action of the active 

 halogen in them. 



But, on the other hand, we find that chloramines — at any rate, those of the 

 aromatic sodium sulphochloramide type — react with amino-acids, peptones, 

 proteins, and many other substances in very much the same fashion as 

 sodium hypochlorite. 



Thus, for example, on adding p-toluene sodium sulphochloramide to an 

 aqueous solution of an amino-acid, toluene sulphonamide is precipitated, and 

 the amino-acid is converted into an unstable chloramino-aeid, which subse- 

 quently decomposes to give an aldehyde and carbon dioxide. In the case of 

 glycine, the reaction may be represented as follows : — 



CH 3 .C 6 H 4 .S0 2 Na : NCI + CH 2 (NH 2 ).COOH = 



CH 2 (NHCl).COONa + CH 3 .C 6 H 4 .S0 2 NH 2 . 

 €H 2 (NHCl).COONa + H 2 = H 2 C : + C0 2 + NaCl + NH 3 . 



u 2 



