400 



RADIATION BIOLOGY 



Hn.C 



CH:CH2 HjC j pCeHj 



C- 

 

 CO2CH3 



2- VINYLPHEOPORPHYRIN-0; 

 MONOMETHYL ESTER 



H,C 



HC 



CHlCHj H3C 



C,H 



2"5 



CH 



HjC 



IRON + FORMIC ACID 



CH ; CH2 H3C 



\. 



-^ HC 



+ OXYGEN 



HjC 



= C- 



CH2 

 H H 9*^2 



HjgCpnOoC 



l/H 

 C^ 







C02CH3 



CM. 



H,C 



CH2 

 CH2 



C'^ 

 



C02CH3 



PHEOPHYTIN 

 ACID 



H39C20O2C 



PROTOPHEOPHYTIN 



GRIGNARD 

 REAGENT 



H^C 



CH :CH2 H3C 



HC 



H3C 



Mg ; 



C2H5 



CH 



H,C 



HC 



CH:CH-> H,C 



V N '' = 



-H 



/ 



CH, 



H H 9'^2 I b 



H39C20O2C CO2CH3 



CHLOROPHYLL a 



CH, 



H3C 



Mg; 



= C- 



CH2 

 CH2 



H39C2002C 



PROTOCHLOROPHYLL 



l^c-" 



I 



C02CH3 



C2H5 



CH 



CH, 



C2H5 



" \ 



CH 



CH3 



Fig. 7-3. Synthetic reactions showing the chemical relations between chlorophyll a 

 and protochlorophyll. {Fischer and Oestreicher, 1939-1940; Fischer, 1940.) 



treicher, 1939; Fischer and Oestreicher, 1939-1940) has confirmed the 

 correctness of this suggestion. Fischer and his coworkers have carried 

 out a series of reactions, illustrated in Fig. 7-3 (Fischer, 1940; Fischer and 

 Oestreicher, 1939-1940), which demonstrate the close relation between 

 chlorophyll a and protochlorophyll. From their investigations it is rea- 

 sonably certain that protochlorophyll is chlorophyll minus the two hydro- 



