Sulphides Thioethers and their Derivatives

The sulphides, or thioethers, whose general formula is R—S—R, may be considered as derivatives of hydrogen sulphide in which 

The monosubstituted derivatives, ethyl ]8 chloroethyl sulphide and ethyl ]8 bromoethyl sulphide, are weak in toxicity, as is also the disubstituted compound aa dichloroethyl sulphide. The disubstituted derivative with both the halogen atoms in the )8 position, jSjS dichloroethyl sulphide, however, is powerfully toxic and vesicant it is more commonly known as Mustard Gas Other derivatives analogous to /SjS dichloroethyl sulphide have been prepared, such as /S/3 dibromoethyl sulphide and /3/S diiodoethyl sulphide, which have similar physiopathological properties, as well as homologues of /3/S dichloroethyl sulphide such as /3/3 dichloropropyl sulphide (I) and /3/3 dichlorobutyl sulphide (II)  

These two substances resemble ]8j8 dichloroethyl sulphide in odour, but show some differences in offensive action, for it has been found that only fiP dichlorobutyl sulphide possesses vesicant action and that to a much milder degree than the ethyl compound.  

Derivatives have also been prepared with the chlorine atom in the y position, like yy dichloropropyl sulphide, whose toxic properties are, however, as yet unknown, and also derivatives with chlorine atoms in the ]8 and y positions, such as jSjS yy tetrachloropropyl sulphide  

Attempts made to prepare substances like 88 dichlorobutyl sulphide with chlorine atoms in the 8 position have not been successful up to the present. 

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