PROPERTIES 



References to Section 4 



1. R. B. Angier, J. H. Boothe, B. L. Hutchings, J. H. Mowat, J. 



Semb, E. L. R. Stokstad, Y. SubbaRow, C. W. Waller, D. B. 

 Cosulich, M. J. Fahrenbach, M. E. Hultquist. E. Kuh, E. H. 

 Northey, D. R. Seeger, J. P. Sickels and J. M. Smith, Science, 

 1946, 103, 667 ; Ann. N.Y. Acad. Sci., 1946, 48, 283. 



2. Waller et al., J. Amer. Chem. Soc, 1948, 70, 19. 



3. Hultquist et al., ibid., 23. 



4. Angier et al., ibid., 25. 



5. Boothe et al., ibid., 27. 



6. American Cyanamid Co., U.S. P., 2442836-7, 2442867, 2443165, 



2444002, 2444005, Brit. App., 12491/48, 14216/48, 24564/48, 

 25001-2/48, 3413/49. 



7. F. E. King and P. C. Spensley, Nature, 1949, 164, 574. 



8. P. Karrer and R. Schwyzer, Helv. Chim. Acta, 1948, 31, 777. 



9. Roche Products Ltd., B.P. 624394, 630751. 



10. Hoffmann-La Roche & Co., B.P. 626171, 628305 ; Roche Products 



Ltd., B.P. 631516. 



11. H. S. Forrest and J. Walker, /. Chem. Soc, 1949, 2077. 



12. J. H. Boothe, J. H. Mowat, B. L. Hutchings, R. B. Angier, C. W. 



Waller, E. L. R. Stokstad, J. Semb, A. L. Gazzola and Y. 

 SubbaRow, /. Amer. Chem. Soc, 1948, 70, 1099. 



13. J. H. Boothe, J. Semb, C. W. Waller, R. B. Angier, J. H. Mowat, 



B. L. Hutchings, E. L. R. Stokstad and Y. SubbaRow, ibid., 

 1949, 71, 2304. 



14. D. E. Wolf, R. C. Anderson, E. A. Kaczka, S. A. Harris, G. E. Arth, 



P. L. Southwick, R. Mozingo and K. Folkers, ibid., 1947, 69, 2753. 



15. R. Purrmann, Annalen, 1940, 546, 98. 



16. J. R. Totter, /. Biol. Chem., 1944, 164, 105. 



5. PROPERTIES OF FOLIC ACID 



Folic Acid 



H. K. Mitchell and R. J. Williams 1 assigned the formula, CigHigOgNg, 

 to the folic acid isolated from spinach leaves, and stated that it was 

 free from sugars or polyhydroxy compounds, but contained a xantho- 

 pterine-like moiety, since its absorption spectrum resembled that of 

 xanthopterine.^ The relationship of folic acid to other members of 

 the group has not definitely been established, but there is some evidence 

 to suggest that it is not identical with the liver L. casei factor.^ 



Liver L. casei Factor (Vitamin Be) 



Crystalline vitamin Be was isolated from liver by Pfiffner et al.^ 

 and E. L. R. Stokstad,^ who obtained it from hot water in the form of 

 yellow platelets which melted above 360° C. The empirical formula 



477 



