BASES OF CHAPTER II. 



/9-Alanine. 



The substance may be obtained synthetically in several ways, the 

 best being from succinimide (Holm [1904]); I mol. of succinimide 

 in 10 per cent, potash solution containing 6 mol. of KOH and I mol. 

 of KOBr is warmed for two hours to 50-60. The resulting /9-alanine 

 is purified by esterification. 



Abderhalden and Fodor [1913] isolated yS-alanine according 

 to Fischer's ester method. The free ester boils at 54 and 10 mm. 

 The hydrochloride melts at 64. On distilling the ester at ordinary 

 pressure it gives the pungent smell of ethyl acrylate which is a good 

 mode of recognition of /S-alanine. 



Synthetic $-alanine forms prisms, melting at 206-207 and decom- 

 posing into acrylic acid and ammonia. 



The hydrochloride melts at 122 -5. 



The sulphate, (C 3 H 7 O 2 N) 2 H 2 SO4 ) decomposes at 1 50. 



The platinichloride, (CgH^N^HsPtClg, crystallises from water or 

 hydrochloric acid in deep yellow needles, m.p. 180; it is soluble in 

 alcohol (Engeland [1908, i]). 



The copper salt, (C 3 H 6 O 2 N> 2 Cu + 6H 2 O, forms azure crystals 

 (Holm [1904]). 



7-Aminobutyric Acid. 



According to Engeland and Kutscher [1910, 3, Ch. Ill, buty- 

 robetaine] ^-aminobutyric acid is precipitated in dilute solution by 

 phosphotungstic acid and also by mercuric chloride in the presence of 

 sodium acetate, but not by mercuric chloride alone. These properties 

 it shares with histidine and methyl-guanidine, from which it may be 

 separated by silver nitrate and baryta, when it appears in the lysine 

 fraction. It can also be separated by distillation of its ester, prepared 

 by Fischer's method. 



7-Amino-butyric acid was first obtained by Schotten [1884] by 

 oxidising piperidylurethane with fuming nitric acid and subsequently 



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