NOMENCLATURE AND SYMBOLS 53 



as rhodoporphyrin and pyrroporphyrin, resemble the blood porphy- 

 rins. Only the latter are given in Table III. It should be noted that 

 the etioporphyrins derived from chlorophyll contain one ethyl group 

 less than the mesoetioporphyrin derived from blood pigment. 



TABLE III 



Some Chlorophyll Porphyrins 



Porphyrin Side chains 



Rhodoporphyrin 4 M, 2 E, 1 P, 1 CO2H 



Pseudoverdoporphyrin 4 M, 1 E, 1 V, 1 P, 1 CO.H 



Pyrroporphyrin 4 M, 2 E, 1 P, 1 H 



Phylloporphyrin 4 M, 2 E, 1 P, 1 H, (1 ^ CCH3) 



Pyrroetioporphvrin 4 M, 3 E, 1 H. 



Phylloetioporphyrin 4 M, 3 E, 1 H, (1 > CCH3) 



2.2. Nomenclature and Symbols 



Some of the porphyrins mentioned in Table I have been named 

 difiFerently by other writers, notably Schumm, but these names have 

 been superseded by the names given in Table I. Table IV supplies 

 a list of such synonyms. 



TABLE IV 



Earlier Names for Porphyrins 



Protoporphyrin Hematoporphyroidin (Schumm), Hematerinsaure 



(Kiister), Snapper's porphyrin, Kammerer's por- 

 phyrin, ooporphyrin 



Deuteroporphyrin Copratoporphyrin (Schumm) 



(Deuterohematin) Copratin 



Coproporphyrin Kotporphyrin, enteroporphyrin 



Uroporphyrin Urinporphyrin 



In medical literature, it is unfortunately still customary to speak 

 of hematoporphyrinuria, instead of porphyrinuria. This dates back 

 to the end of the last century when hematoporphyrin was the only 

 porphjTin known (c/. above). We now know that it does not occur 

 in nature, and that the porphyrins to be found in urine are copropor- 

 phyrin and uroporphyrin (c/. Chapter XII). 



In order to save space, we have developed a simplified diagram- 

 matic representation of the porphyrin nucleus. H. Fischer has intro- 

 duced the symbol,^ (Fig- 2) for porphin which depicts the eight 

 /S-positions of the four pyrrole nuclei and thus allows satisfactory 



