58o SCIENCE PROGRESS 



There is an interesting class of hypnotics containing sulphur 

 which illustrate the influence of the ethyl group in the de- 

 velopment of the soporific effect. They are produced by the 

 condensation of ethyl mercaptan, C2H5.SH, with a ketone, 

 RR^ : C : O, whereby a mercaptol, RR^ : C(S . C2H5)2, is pro- 

 duced, which is then oxidised to a disulphone XXII. 



Rvp/SOj.CoHs CH,x ^ /SO^.CjHs 



Ri^ *" \S02 . C2H5 CHs/ ^ ^SO; . C2H5 



XXII. XXIII. 



When acetone (CH3)2C : O is employed in the condensation, 

 snlphonal (CH3)2C(S02 . C2H5)2 is ultimately obtained ; when 

 diethyl ketone is used, tetronal (C2H5)2C(S02 . C2H5)2 is the 

 final product, whilst methyl ethyl ketone leads to the pro- 

 duction of trional (Bayer). The hypnotic action increases with 

 the number of ethyl groups, tetronal having the strongest 

 narcotic effect. Trional, the intermediate member of the series, 

 is, however, most often employed. 



Antiseptics and Astringents 



In considering the febrifuges, aniline was taken as the 

 starting-point, and, in a discussion of antiseptics, phenol (carbolic 

 acid, XXIV.) may be regarded as the prototype. 



OH OH OH OH 



Bri^^Br r^CO,H 



Brl^Br L^ 



CHs CH3 



XXIV. XXV. XXVI. XXVII. 



Phenol was, in fact, the first antiseptic recommended in surgical 

 practice when it was employed in the original method of 

 operation introduced by Lister. Although free from the 

 destructive action exerted by aniline on the red corpuscles, 

 phenol is a powerful irritant, and can only be administered 

 internally in very small doses ; in larger amounts it has a 

 paralysing effect on the motor nerve-endings. The intro- 

 duction of a methyl group into the nucleus as in para-cresol 

 (XXV.) brings about a diminution in the poisonous character 

 of phenol and at the same time increases the germicidal power 

 of the substance. On this account the isomeric cresols (para-, 

 meta-, and ortho-) are extensively used in disinfectants of the 

 lysol type. The further substitution of halogen atoms for the 



