EXPERIMENTAL. 95 



184. Heated side by side with the corresponding substance obtained from 

 gliadin, the hydantoic acid from glutenin melted at 2 higher. 



Carbon and hydrogen: 0.3277 gram substance, dried at 80, gave 0.8067 gram CO 2 and 



0.1891 gram H 2 O. 

 Calculated for C 16 H 18 O 3 N 2 , C 67.07, H 6.35 p. ct.; found, C 67.14, H 6.42 p. ct. 



From the filtrate from the amino-valerianic acid there was further obtained 

 1.41 grams of alanine. The alcoholic solution which contained the proline 

 was evaporated to dryness under reduced pressure and the dried residue 

 again treated with boiling absolute alcohol. Even after several repetitions 

 of this process no substance insoluble in alcohol could be obtained. The 

 alcohol- soluble substance, when dried, weighed 35.54 grams. A copper salt 

 was prepared from this in the usual manner, and its solution evaporated to 

 dryness under reduced pressure. The dried residue was extracted with boil- 

 ing absolute alcohol in order to remove the /-proline copper. The residue 

 insoluble in alcohol, when recrystallized from water, gave 15.53 grams of 

 racemic proline copper, equivalent to 10.9 grams of proline. 



Water : 0.3618 gram substance lost at 110 0.0399 gram of H 2 O. 

 Copper : 0.3176 gram substance, dried at 110, gave 0.0856 gram CuO. 

 Calculated for C 10 H 16 O 4 N 2 Cu 2H 2 O, H 2 O 11.00 p. ct. ; found, H^O 11.03 p. ct. 

 Calculated for C 10 H 16 O 4 N 2 Cu, Cu 21.79 P- ct - \ found, Cu 21.54 p. ct. 



The alcoholic solution of the /-proline copper salt was evaporated to dry- 

 ness, the copper removed, and the proline identified as the phenylhydantoin 

 which was prepared according to the directions of Fischer. 1 The substance 

 thus prepared was at once pure and melted at 143. 



Carbon and hydrogen: 0.2822 gram substance, dried in vacuo over H 2 SO 4 , gave 0.6866 



gram CO 2 and o. 1494 gram H 2 O. 



Nitrogen: 0.1025 gram substance gave NH 3 = 1.33 cc. HC1 (i cc. HC1 = o.oi gram N). 

 Calculated for C 12 H 12 O 2 N 2 , C 66.60, H 5.61, N 12.99 p. ct. ; found, C 66.36, H 5.88, 



N 12.98 p. ct. 



f Fraction IV, A. Temperature of bath, up to 155. ) 

 (Pressure, 1.5 mm. Weight, 43.32 grams. j 



This fraction was shaken out with ether in the usual way and the ether 

 allowed to evaporate spontaneously. No evidence of the presence of phenyl- 

 alanine was obtained. The residue of ester was saponified with concentrated 

 hydrochloric acid and the hydrochloride decomposed with ammonia. The 

 free acid crystallized in the characteristic form of leucine and decomposed at 

 298. There were obtained 13.99 grams of leucine. 



Carbon and hydrogen: 0.2906 gram substance, dried at 110, gave 0.5825 gram CO 2 



and 0.2690 gram H 2 O. 

 Calculated for C 6 H 13 O 2 N, C 54.89, H 10.01 p. ct. ; found, C 54.67, H 10.28 p. ct. 



1 Fischer, E., Zeitschrift fur physiologische Chemie, 1901, xxxin, p. 151. 



