443 Pyrroles, Porphyrins and Related Compounds 



Besides the natural analogues, many vitamin 8,0 "var- 

 iants have been prepared by addition of analogues of the 



1-' H. W. Dion, D. G. Calkins and J. J. Pfiffner, /. Am. Chem. Soc. 74 

 1108 (1952). 



-"]. E. Ford, E. S. Holdsworth, S. K. Kon and J. W. G. Porter, 

 Nature 171 148 (1953). 



-^ H. G. Heinrich (Editor), "Vitamin Bu and Intrinsic Factor, First 

 European Symposium, Hamburg, 1956." M. E. Coates and S. K. Kon, 

 Ferdinand Enke. Stuttgart, 1956, p. 72. 



-- F. B. Brown, J. C. Cain, Dorothy E. Gant, T. F. J. Parker and 

 E. Lester Smith, Biochem. J. 59 82 (1955). 



-' H. W. Dion, D. G. Calkins, and J. J. Pfiffner, /. Am. Chem. Soc. 

 76 948 (1954). 



^S. K. Kon, Biochem. Symposium No. 13, p. 17 (1955). 



^'' H. G. Heinrich (Editor), "Vitamin B,o and Intrinsic Factor, First 

 European, Hamburg, 1956." J. W. S. Porter, Ferdinand Enke, 

 Stuttgart, 1956, p. 43. 



-•'J. B. Armitage, J. R. Cannon, A. W. Johnson, T. F. J. Parker, 

 E. Lester Smith, W. H. Stafford and A. R. Todd, /. Chem. Soc, 3849 

 (1953). 



-" R. Barchielli, G. Boretti, P. Julita, A. Migliacci and A. Minghetti, 

 Biochim. et Biophijs. Acta 25 452 (1957). 



-* Wilhelm Friedrich and Konrad Bernhauer, Chem. Ber. 89 2030 

 (1956). 



-^ Wilhelm Friedrich and Konrad Bernhauer, Angew. Chem. 65 627 

 (1953). 



'" Clifford H. Shunk, Franklin M. Robinson, James F. McPherson, 

 Marjorie M. Gasser and Karl Folkers, 7. Am. Chem. Soc. 78 3228 

 (1956). 



31 G. E. W. Wolstenholm and Maeve O'Connor (Eds.), CIBA 

 Foundation Symposium on "The Chemistry and Biology of Purines," 

 E. Lester Smith, The chemistry of neiv purines in the Bi2 series of 

 vitamins, Little, Brown & Co., Boston, 1957, pp. 160-168. 



3- Wilhelm Friedrich and Konrad Bernhauer, Chem. Ber. 90 1966 

 (1957). 



■'^ Hanswerner Dellweg and Konrad Bernhauer, Arch. Biochem. and 

 Biophijs. 69 74 (1957). 



■''* Konrad Bernhauer, Hanswerner Dellweg, Wilhelm Friedrich, 

 Gisela Gross and F. Wagner, Z. Naturforsch. 156 336 (1960). 



3^" K. Bernhauer, H. W. Dellweg, W. Friedrich, G. Gross, F. Wagner, 

 and P. Zeller, Helv. Chim. Acta 43 693 (1960). 



^^ Konrad Bernhauer, Elisabeth Becher, Gisela Gross and Georg 

 Wilharm, Biochem. Z. 332 562 (1960). 



3^" K. Bernhauer, F. Wagner and P. Zeller, Helv. Chim. Acta 43 696 

 (1960). 



""Wilhelm Friedrich and Konrad Bernhauer, Chem. Ber. 91 2061 

 (1958). 



^" G. Boretti, A. DiMarco, T. Fuoco, M. P. Marnati, A. Migliacci and 

 C. Spalla, Biochim. et Biophijs. Acta 37 379 (1960). 



