in* ON THE SYNTHESIS OF ALBUMINS 137 



Diglycyl-phenyl-alanin : 



/COOH 

 NH 2 CH 2 CO . NHCH 2 CO . NH . CH^ 



CH 2 . C 6 H 5 



Derivatives of Cystin (VII.) 



The constitutional formula of cystin is given on p. 57. 

 Diglycyl-cystin : 



CH 2 CO . NHCHCH 2 S . S . CH 2 . CHNH . COCH 2 

 NH 2 COOH " COOH NH 2 . 



Di-alanyl-cystin : 



CH 3 :CH.CO.NH.CH.CH 2 S.S.CH 2 .CH.NH.CO.CH.CH 3 

 NH 2 COOH " COOH NH 2 . 



Dileucyl-cystin : 



C 4 H 9 . CH . CO . NH . CH . CH 2 . S . S . CH 2 . CH . NH . CO . CH . C 4 H 9 

 NH 2 COOH COOH NH 2 . 



Derivatives of Aspartic Acid (VIII.) 



The constitutional formula of aspartic acid is given on p. 34. 

 Glycyl-asparagin : 



CH 2 .CONH 2 

 NH 2 CH 2 CO.NH.CH 



COOH 

 Leucyl-asparagin : 



CH 9 - CONH 2 . 

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



COOH 

 Leucyl-aspartic acid : 



CH 2 CONH 2 

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



COOH. 



Asparagyl-monoglycin (inactive) : 



CO .NH.CH 2 .COOH COOH 



CH .NH 2 or CH.NH 2 



CH 2 . COOH CH 2 . CO . NH . CH 2 . COOH. 



By hydrolysis it gives rise to glycocoll and inactive aspartic acid. 

 Fumaryl-di-aspartic-acid-ester : 



CO.NH.CH.CH 2 .COOC 2 H 5 

 CH COOC 2 H 5 



CH COOC 2 H 5 



CO . NH . CH . CH 2 . COOC 2 H 5 . 



