118 PROTEIN POISONS 



portion was freely soluble. On cooling and concentrating 

 the alcoholic solution, a fine yield of crystals was obtained. 

 The crystals from several samples were united and recrys- 

 tallized from hot absolute alcohol until the solution was 

 clear and colorless. Macroscopic bundles of needles were 

 thus obtained, showing very characteristic grouping. They 

 were washed in alcohol and in ether, dried upon porous 

 plates, the operations being repeated until samples from 

 two recrystallizations melted side by side within 1 or 1.5. 

 The crystals are pure white, readily soluble in benzol, 

 chloroform, and in glacial acetic acid as well as in alcohol, 

 and melt at 203. When boiled with sodium hydroxide, 

 ammonia is given off; after removing benzoic acid by boil- 

 ing with hydrochloric acid, the resulting product reduces 

 Fehling's solution. 



0.4150 gram gave 0.00891 gram N, corresponding to 2. 14 per cent. N. 

 . 4220 gram gave . 00962 gram N, corresponding to 2.279 per cent. N. 

 Average is 2.213 per cent. N. 



These characteristics suffice to identify the compound 

 as glucosamin benzoate which Pumm reports as melting 

 at 203. Kueny prepared different benzoates of glucosamin 

 by varying the conditions of the experiment. The one most 

 readily formed was the tetrabenzoate, melting at 199 

 when recrystallized from alcohol, and at 207 when re- 

 crystallized from glacial acetic acid. He tried by various 

 methods to prepare a pentabenzoate, but without success. 

 Langstein prepared glucosamin benzoate from egg-white, 

 which, after once recrystallizing from hot alcohol, melted 

 at 201 to 202, and gave 1.95 per cent, of nitrogen. The 

 theoretical amount of nitrogen in the tetrabenzoate is 

 2.35 per cent. Thus, the benzoate prepared from the 

 haptophor of egg-white agrees with glucosamin benzoate 

 prepared from glucosamin and from egg-white, at least as 

 well as those preparations do with each other. Numerous 

 observers have found glucosamin in egg-white, and this 

 work shows that it remains in the haptophor when egg-white 

 is disrupted by alkaline alcohol. 



