567 



Pteridines and Flavines 



was isolated from the same culture. This metabolite re- 

 sembles 3-oxyanthranilic acid, known to be a biosynthetic 

 precursor of nicotinic acid. 



Toru Masuda, Pharm. Bull. (Japan) 4 71 (1956). (Iso- 

 lation) 



Idem., ibid. 5 28 (1957). (Structure) 



Toru Masuda, Toyokazu Kishi, Mitsuko Asai and Satoru 

 Kuwada, Chem. and Pharm. Bull. (Japan) 7 361 (1959). 

 (Synthesis) 



1055 Rhizopterin (N"'-Formylpteroic Acid) (Streptococcus lactis R 

 Factor) (SLR Factor), Ci5Hio04N„, light yellow crystals, 

 m.p. >300°. 



OH 





CH.— N— / \— COOH 

 CHO 



H..N 



Rhizopus nigricans 



Edward L. Rickes, Louis Chalet and John C. Keresztesy, 

 J. Am. Chem. Soc. 69 2749 (1947). 



Donald E. Wolf, R. Christian Anderson, Edward A. Kaczka, 

 Stanton A. Harris, Glen E. Arth, Philip L. Southwick, Ralph 

 Mozingo and Karl Folkers, ibid. 69 2753 (1947). (Synthesis) 



1056 Riboflavin (Vitamin B^), Ci7H2i,OeN4, yellow-orange micro- 

 crystalline powder, m.p. ~280° (rapid heating), [a]ir^ 

 -112° to -122° (50 mg. in 2 ml. of 0.1 N alcoholic 

 sodium hydroxide diluted to 10 ml. with water). 





CHo 



I 

 (CHOH)3 



CH3 



CH3 



CHoOH 



Ascomycetes such as EremotheciuTU ashbyii and Ashbya 

 gossypi produce high yields. 



Leland A. Underkofler and Richard J. Hickey, "Industrial 

 Fermentations," Chemical Publishing Co., Inc., New York, 

 1954 Vol. II, Richard J. Hickey, Production of riboflavin by 

 fermentation, Chap. 5, pp. 157-190. (A review) 



