574 SCIENCE PROGRESS 



called reduction, and is carried out very simply on a large 

 scale by heating the nitrobenzene with iron filings suspended 

 in slightly acidified water. Aniline resembles ammonia in 

 some of its properties, for it is a base capable of yielding well 

 cr^-stallised salts such as aniline hydrochloride and sulphate. 

 Both the base and its salts have a marked physiological action, 

 and in fact they are powerful poisons. These substances have 

 a beneficial eff'ect in lowering the temperature and subduing 

 pain, but on the other hand they have a very deleterious action 

 on the red corpuscles of the blood, bringing about a destruction 

 of the hemoglobin. Aniline poisoning is characterised by the 

 blue appearance of lips and nails, failure of respiration, giddiness, 

 coma, and finally death. These acute symptoms are, however, 

 considerably diminished by converting aniline into its acetyl 

 derivative, acetanilide, a substance which has been emplo3"ed 

 as an antipyretic under the name of antifchrin ^ (formula IV.). 

 This compound is readily prepared by heating together aniline 

 and glacial acetic acid : CeH^NH,, CH3 . CO2H — H2O = 

 C6H5.NH.CO.CH3. 



NH.CO.CH3 NH, NH.CO.CH3 NH.CO.CH(OH).CH, 



OH OC.H, OC,H5 



IV. V. VI. VII. 



It should, however, be borne in mind that the acetyl group 

 CO.CH3 is readily removed within the tissues either by 

 h3'drol3^sis or oxidation, so that aniline is regenerated, and its 

 poisonous effect is produced only in a less acute form than 

 when the base itself is administered. The continued exhibition 

 of antifebrin is to be deprecated as likely in the long run 

 to produce aniline poisoning. It has been found that aniline 

 is converted in the system into para-aminophenol (formula V.), 

 which is then eliminated in combination either with sulphuric 

 acid or glycuronic acid COH . [CH . OH]4. CO^H. This action 

 of the organism in converting aniline into the less poisonous 

 para-aminophenol has been taken into account in the production 

 of the antipyretics of the phenacetin series. 



^ The full graphical representation of the benzene ring or nucleus in formulae 

 I. to III. has now been simplified to the hexagon represented in formulae IV., V., 

 etc. It will be seen that this benzene nucleus is present in the majority of the 

 synthetical drugs discussed in this article. 



