THE ADRENAL GLANDS 81 



of adrenaline from the adrenals are von Ftirth, an 

 Austrian; Abel, professor at Johns Hopkins; and 

 Takamine, a Japanese domiciled in the United 

 States. Friedmann, a German, succeeded in pro- 

 ducing adrenaline synthetically in the chemist's 

 laboratory. While it is not my intention in a 

 volume of this kind to enter into any details re- 

 garding the chemical steps involved in the isola- 

 tion of hormones, the briefest outline of Abel and 

 Takamine's methods for isolating adrenaline from 

 its gland will be given. Even though such an out- 

 line proves too "technical," it can hardly be omit- 

 ted from a book purporting to deal with hormone 

 action. 



Preparation of adrenaline. Very concentrated 

 adrenal extracts are largely freed from inactive 

 substances by treatment with alcohol, lead acetate, 

 etc.; then the active substance is precipitated in 

 microscopic crystals by the addition of concen- 

 trated ammonia. The precipitate is then purified 

 by repeatedly dissolving in acid and reprecipitat- 

 ing with ammonia. The resulting prismatic needles 

 or rhombic plates are those of the purified or iso- 

 lated active principle adrenaline. 1 



J For the benefit of students of chemistry who may read this 

 volume, a word may be added as to the synthetic production of 

 adrenaline. This may be obtained by the action of methylamine 

 upon chloroaeetopyrocatechin : 



C C H 3 ( OH ) a COCH 2 C14-NH 2 CH 3 -C^ ( OH ) a . COCH, . NHCH 8 . HC1 

 The methylamino aceto-pyrocatechin so obtained yields adrena- 

 line on reduction. 



