GH, — C = C— CHs 



I i 

 CO CO 



\/ 



NH 



The said transfurinatidii of haematoporphyrin takes place 

 jutltring by Kiister's description, very easily and I hoped there- 

 fore. that eveu tlie uxidation of sniall quantifies of phylloporpliyrin 

 at niy disposai might lead tu positive results. These hopes hâve 

 been justified as will be shown in the course of this paper. 



I used phyliuporpliyrin which contained a small adniixture of 

 sonie othcr sul)staiie('. |irobably pbvllorul)in. Its solution caused 

 a faint l)and in tlie rt-d part of the speetnim. wliicli is not sbovvn 

 by pure piiyl!opor|ilivrin. It bas been prepared froni phyllocyanin; 

 the latter was converted into phvllotaonin b}^ treatment with an 

 alkali and then beated in a solution of aleoholic potash to 190* in 

 sealed tubes. Tbe crude product obtained bas been purified by al- 

 cohol. which dissolves chietly phyllojiorphyrin leaving otber substan- 

 ces undissolved. Not quite 5 gr. of the jireparation obtained were dis- 

 solved in 500 cm^ of glacial acetic acid, 41 gr. of bichromate of 

 sodium, dissolved in a little water. added and tbe whole beated on 

 the water bath as long as a sample drawn gave the ebromic acid 

 reaction distinctly. As soon as tbe hitter test became but faint the 

 acetic acid was distilled off. at first by direct flame, afterwards 

 on a water bath under redueed pressure. The residue I treated with 

 an amouut of sulphuric acid necessary to décompose the acétates 

 of chromium and sodium, formed in the course of tbe l'eaction, fil-, 

 tered off some undissolved nuttter and extracted the filtrate three 

 times with etiier. Tiie joint extracts were evaporated to dryness and 

 a niass obtained, which at first thick and (iily became after stan- 

 ding crystalline. Assuming. that similarly as in the case of haema- 

 to])orphvrin two substances were formed, namely the iniide and an- 

 hydride of the tbreebasic baematic acid I decided, in order to sim- 

 plifv matters, to décompose tbe imide and to obtain if possible the 

 anhydride uamed and identifv it. With this end in view I dissol- 

 ved the etiiereal residue in some warm water and an excess of car- 

 bonate of Sodium and left tlie solution af rest for 24 hours, after 

 which time the mass "bas been acidulated with sulphuric acid and 

 again extracted with ether. The ethereal extract gave <in evapora- 



1» 



