x HJEMIN 517 



The formation of haematin out of Schalfe Jew's acet-haemin 

 Zaleski l expresses by the equation : 



C 34 H 33 ON 4 ClFe + 2HBr + 2H 2 = C 34 H 38 6 N 4 + FeBr 2 + HC1. 



Acet-haemin. Hsematin. 



According to this view Schalfejew's acet-haemin is no longer 

 regarded as an acetyl-haemin, nor does the /3-haeniin of Morner 

 represent a propionyl - haemin, or an ethyl -ester of 'acet-haemin.' 

 As little as it is possible to split off acetic acid from ' acet-hsemin,' 2 as 

 little can an alphyl-oxy group or a propionic or acetic acid remainder 

 be obtained from /2-haemin. 3 



Ktister is of the opinion that all the haemins enumerated above 

 (acet-haemin, Nencki and Sieber's haemin, /3-haemin, Cloetta-Rosen- 

 feld's hsemin) are one and the same ; that only one haemin exists, with 

 the formula : 



The discrepancies in the formulae given above are attributed by Kiister 

 to insufficient recrystallisation. He also adduces direct proof that 

 these ' haemins ' are really identical. On treating the different haemins 

 with cooled anilin, the chlorine atom is removed, and amorphous pro- 

 ducts are obtained, all of which, after careful washing in very dilute 

 acetic acid, and after long extraction with ether, agree in giving the 

 formula : 



C 34 H 32 4 N 4 Fe. 



This compound is called a ' de-hydrochlorid-haemin.' By the same 

 methods as are employed in making acet-haemin, the de-hydrochlorid- 

 haemin may be reconverted into acet-haemin. By treating the latter 

 with watery solutions of alkalies, the chlorine becomes replaced by a 

 hydroxyl group, and ' haematin ' is formed : 



C 34 H 34 5 N 4 ClFe. 



This formula corresponds to the old one, first given by Hoppe-Seyler, 

 namely : 



Now ' haematin ' obtained in this way from haemins cannot be recon- 

 verted into haemin, because the saponification with alkalies does not 

 simply substitute a hydroxyl group for the chlorine, but produces also 

 some other change whereby the configuration of the ' haematin ' 

 molecule is altered. 4 



1 Zaleski, Zeitschr. f. physiol. Chem. 37. 54 (1904). 



2 Nencki and Zaleski, ibid. 30. 396-397, 403-404 (1900). 



3 Kiister, Ber. d. deutsch. chem. Ges. 35- 2951 (1902). 



4 W. Kiister, Zeitschr. f. physiol. Chem. 4O. 396 (1904). 



