THE SYNTHESIS OF THE PROTEINS 21 



In order to introduce another glycyl residue into diglycinimide, the 

 chloracetyl derivative was prepared, from which by the action of am- 

 monia glycyl-diglycinimide, 



NH 2 . CH-, . CO . NH . Cttj . CO NH OC . CH 2 . NH 2 , 



did not result ; but ammonia was lost and a compound probably of the 

 formula 



CH 2 . CO . NH . CH 2 . CO NH OC . CH 2 . NH 



I I 



was obtained. 



The homologous alanine glycine imide, 



CH 3 . CH . (NH 2 ) CO NH CO . CH 2 . NH 2 , 



was obtained by the action of ammonia at a low temperature upon methyl 

 dichlorodiacetimide, prepared from chloropropionitrile and chloracetic 

 acid. 



Neither diglycinimide nor benzoyldiglycinimide were hydrolysed by 

 pepsin or by trypsin. 



