239 Quinones 



simple acetate and terpenoid biosynthetic routes. Mevalonic 

 acid was incorporated into the molecule by rats (especially vita- 

 min A-deficient rats) and by rat liver, while 2,3-dimethoxy-5- 

 methyl-l,4-benzoquinone and D,L-tocopherol were not.'-'^ This 

 contrasts with evidence that 2-methyl-l,4-naphthoquinone is 

 used as a precursor of vitamin K by rats.'-" Evidently, no experi- 

 mental work has been published on biosynthesis in microor- 

 ganisms. 



a. BENZOQUINONES 



490 Tetrahydroxybenzoquinone, C,,H40(j, bluish black plates, no 

 melting point. 



O 



HO II OH 



HO 11 OH 

 O 



Pseudomonas beiierinckii Hof grown on salted beans. 

 The substrate is meso-inositol, which probably is a normal 

 constituent of beans. 



T. Hof, Rec. Trav. Botan. Neerland. 32 92 (1935). (Isola- 

 tion) 



A. J. Kluyver, T. Hof and A. G. J. Boezaardt, Enzymologia 

 7 257 (1939). (Structure) 



Paul W. Preisler and Louis Berger, /. Am. Chem. Soc. 64 

 67 (1942). 



491 Gentisylquinone, CjHcOs, yellow needles, m.p. 76°. 



O 



CHoOH 



O 



PenicilliuTn patulum Bainier probably produces a little 

 of this quinone under certain conditions, although it may 

 be an artifact, since larger quantities of the corresponding 

 hydroquinone are produced. It has been isolated as a 

 deep violet colored complex, m.p. 86-89°, with the hydro- 

 quinone. 



-' U. Gloor and O. Wiss, Arch. Biochem. and Biophys. 83 216 

 (1959). 



-«C. Martius and H. O. Esser, Biochem. Z. 331 1 (1958). 



