7o8 



SCIENCE PROGRESS 



sponding organic stibinic acids are produced, and these three 

 substances were shown by Miss Micklethwait and the author 

 to yield meta-mtro derivatives, from which, on reduction, 

 aromatic amino-compounds containing antimony were obtained. 

 These amines had some trypanocidal action, but were also 

 very irritant on injection. Their production is shown in the 

 following diagram, which illustrates the genesis of the series 

 from the Grignard reagent and antimony trichloride : 



6Mg(C 6 H 5 ) . Br + 2 SbCl 3 



'(C 6 H 5 ) 3 Sb- 

 C 6 H 5 . SbCl 4 (C 6 H 6 ) 2 SbCl 3 



C 6 H 5 . SbO(OH) 2 (C 6 H 5 ) 2 SbO(OH) 



{^SbO(OH) 2 

 N0 2 



( )sbO(OH) 2 



NH 2 



_ * 

 <_)sb(OH) 2 



NH 2 



L N0 2 J 



L NH 2 J 



(C 6 H 5 ) 3 SbCl 2 

 (C 6 H 5 ) 3 Sb(OH) 2 



SbO.OH 



Sb.OH 



L NQ 2 J* 



L NH 2 J 



Sb. 



Owing to the fact that the oxidised antimony radical induces 

 nitration in the meta-position, all the foregoing amines are meta- 

 derivatives, differing in this respect from atoxyl, which is a 

 para-compound. But within the last few months the isolation 

 of para-aminophenylstibinic acid has been accomplished. The 

 starting-point is acetyl-^-phenylenediamine (V.), which when 

 diazotised combines, as was shown by P. May, with antimony 

 chloride ; this double salt (VI.) when gently warmed with dilute 

 alkali and copper powder yields antimony -atoxyl, sodium para- 

 aminophenylstibinate (VII.) : 



CH3CO.NH/" "\nH 2 -> CH3CO.NH./" ~\N 2 Cl.SbCl 3 



v. vi. 



CH3CO . NH/" ~\sbO(OH) 2 -» NH 2 /" AsbO(OH) . ONa 





VII. 



