742 VIII. PROVITAMINS D AND VITAMINS D 



(1925), the antirachitic vitamin, ^^ which up to this time had no satisfac- 

 tory name, was christened "vitamin D" l\v McColhim.^'' 



Cholesterol was ultimately shown to be devoid of provitamin D activity; 

 the positive results obtained with impiu'e cholesterol Avere ascribed to some 

 impurity activated l)y ultraviolet irradiation.^''"''^ Almost simultaneously 

 several groups of Avorkers came to the conclusion that the pro- 

 vitamin D is ergosterol or a sterol with a constitution similar to that of 

 dehydrocholesterol.^^"^' 



Crystalline vitamin D was isolated initially by Reerink and van Wijk''*'^* 

 in 1929; however, Linsert^"'^^ is generally given credit for being the first to 

 obtain a pure preparation of vitamin D. 



The multiple nature of a itamin D soon became evident with the demon- 

 stration"^ of a new provitamin D, 22-dihydroergosterol, followed shortly 

 thereafter by the synthesis of 7-dehydrocholcsterol'''' and its isolation from 

 hog skin.^^ It was found that the vitamin D obtained from tuna and hali- 

 but oils as a crystalline ester consisted almost entirely of activated 7- 

 dehydrocholesterol.^^"""^ In 1937 Schenck''" succeeded in preparing the 

 pure vitamin (D3) from irradiated 7-dehydrocholesterol. 



^ E. V. MpCollum, X. Simmonds, J. E. Beckor, and P. G. Sliiplcy, Bull. Johns Hop- 

 kins Hosp., 33, 229 (1922). 



^* E. V. McCollum, X. Siinmonds, J. 1^. Ik'cker, and P. (J. Shipley, J. Biol. Chem., 

 65, 97-100 (1925). 



" F. W. Schlutz and M. Morse, Am. J. Diseases Children, 30, 199-209 (1925). 



38 O. Rosenheim and T. A. Webster, J. Sac. Chem. Ind., 4-5, 932 (1926). 



" O. Rosenheim and T. A. Webster, Biochem. J., 21, 127-129 (1927). 



••0 I. M. Heilbron, E. D. Kamm, and R. A. Morton, J. Soc. Chem. Ind., 45, 932 

 (1926). 



" I. M. Heilbron, E. D. Kamm, and R. A. Morton, Biochem. J., 21, 78-85 (1927). 



« R. Pohl, Nachr. Ges. Wiss. GoUitii/en, Math, physik. Klasse, III, 142-145 (1926). 



" R. Pohl, Nachr. Ges. Wiss. Gottingen, Math, physik. Klasse, III, 185-191 (1926). 



** A. Windaus and A. F. Hess, Nachr. Ges. Wiss. Gottingen, Math, physik. Klasse, III, 

 175-184 (1926). 



■** A. Windaus and F. Holtz, Nachr. Ges. Wiss. Gottingen, Math, physik. Klasse, III, 

 217-225 (1927). 



« O. Rosenheim and T. A. Webster, Lancet, 1927, I, 306-307. 



« O. Rosenheim and T. A. Webster, Biochem. J., 21, 389-397 (1927). 



« E. H. Reerink and A. van Wijk, Biochem. J., 23, 1294-1307 (1929). 



« E. H. Reerink and A. van Wijk, Biochem. J., 25, 1001-1010 (1931). 



5» O. Linsert, annotation in Ann., 489, 269 (1931). 



61 A. Windaus, O. Linsert, A. Liittringhaus, and G. Weidlich, Ann., 492, 226-241 

 (1931). 



62 A. Windaus and R. Langer, Ann., 508, 105-114 (1933). 



" A. G. Boer, E. H. Reerink, A. van Wijk, and J. van X'^iekerk, Proc. Acad. Sci. 

 A7nsterdam, 39, 622-632 (1936); Cheyn. Abst., 30, 5636 (1936). 



<>* A. Windaus and F. Bock, Z. physiol. Chem., 245, 168-170 (1937). 

 « H. Brockmann, Z. physiol. Chem., 241, 104-115 (1936). 



66 H. Brockmann, Z. physiol. Chem., 245, 96-102 (1937). 



67 H. Brockmann and A. Busse, Z. physiol. Chem., 249, 176-180 (1937). 



68 E. J. H. Simons and T. F. Zucker, J. Am. Chem. Soc, 58, 2655 (1936). 



6' G. A. D. Haslevvood and J. C. Di'ummond, Chemistry & Industry, I4 (J- Soc. Chem. 

 Ind., 55), 598-599 (1936). 



«» F. Sohenck, Naturwissenschajten, 25, 159 (1937). 



