in ON THE SYNTHESIS OF ALBUMINS 125 



glycerine into an anhydride which differed from that which Curtius 

 obtained. The constitution of the new anhydride could not, however, 

 be determined. 



Lilienfeld J states that with the help of Wolkowicz he succeeded in 

 obtaining the following results : Glycocoll-ethyl-ester prepared by 

 Curtius's method, see p. 116, is readily converted into the biuret- 

 base by boiling with potassium bisulphate on the water-bath. Simul- 

 taneously di-methylamin, carbon dioxide, and ethylether are given off. 

 The formula Lilienfeld attributed to the biuret-base is : 



/ COCH 2 NH 2 



NH\ or 'di-mono-amidacetimid.' 



X COCH 2 NH 2 



On boiling the biuret-base or its carbonate a flocculent precipitate 

 separated out, which was insoluble in water, alcohol, and dilute acids, 

 readily soluble in pepsin + HC1 at 37. 



By condensing the ethylesters of leucin, tyrosin, and glycocoll, he 

 obtained a substance which was precipitable by ammoniacal basic lead- 

 acetate, sublimate ; tannic, phosphotungstic, phosphomolybdic, and 

 picric acids, and by mercury-potassium iodide, but not precipitable by 

 nitric and acetic acids or potassium-ferrocyanide. It further gave the 

 reaction of Millon, the xanthoproteic test, the biuret-reaction, and the 

 ' reactions of Adamkiewicz and Liebermann. 



The author fails to see how Lilienfeld obtained the tryptophane 

 reaction. 



Lilienfeld also states to have prepared a typical albumin by 

 treating the base of Curtius with amino-acid-esters in the presence of 

 small amounts of formaldehyde and a * condensing medium/ the nature 

 of which, * for obvious reasons,' he has not divulged. 



A great step forward in synthetising substances resembling albumins 

 was taken when Emil Fischer 2 commenced his important researches 



1 Leon Lilienfeld, Arch.f. (Anat. u.) Physiol. 1894, pp. 383 and 555. 



2 E. Fischer and E. Fourneau, Ber. d. deutsch. chem. Ges. 34. 2868 (1901) ; 

 E. Fischer, ibid. 35. 1095 (1902) [I.]; E. Fischer (and P. Bergell), 'Hydrolysis 

 of Proteids,' Vartrag auf der Karlsbader Naturforscherversammlung, 1902. Autoreferat 

 Gliemikerzeitung, 1902, II. p. 939 ; E. Fischer, ' Derivatives of Polypeptids,' Ber. d. 

 deutsch. chem. Ges. 36. 2094 (1903); E. Fischer and E. Otto, 'Derivatives of 

 Dipeptids,' ibid. 36. 2106 (1903); E. Fischer and P. Bergell, 'Behaviour of 

 Dipeptids towards Pancreatic Ferments,' ibid. 36. 2592 (1903) ; E. Abdevhalden and 

 P. Bergell, 'Dissociation of Peptids in the Body,' Zeitschr. f. physiol. Chem. 39. 9 

 (1903) ; E. Fischer, Ber. d. deutsch. chem. Ges. 36. 2938 (1903) ; E. Fischer, 

 'Synthesis of Polypeptids' [II.], Ber. d. deutsch. chem. Ges. 37. 2486 (1904); E. 

 Fischer, and Umetaro Suzuki [III.], 'Derivatives of a-Pyrrolindin-carboxylic Acid,' 

 ibid. 37. 2842 (1904). E. Fischer, ' Derivatives of Phenylalanin ' [IV.], ibid. 37. 

 3062 (1904) ; E. Fischer and E. Abderhalden [V.], ' Derivatives of Prolin ' (a-pyrrolidin- 



