2 Essays in Biochemistry- 



group consists of polyacetylenic compounds, with which the major part 

 of this paper will be concerned. 



Since the chemistry of most of the compounds discussed has not 

 been completely elucidated and since their biological significance is 

 entirely unknown, much that will be said is purely speculative. It is 

 hoped that this will justify itself in some measure by suggesting further 

 paths for exploration in relation both to chemical and to biological 

 questions. For purposes of discussion, the compounds may be divided 

 into groups comprising quinones, sesquiterpenes, larger polycyclic mole- 

 cules, halogenated aromatic compounds, and polyacetylenes. 



Quinones 



This group, of which there are many examples among products of 

 fungal origin, as well as among those produced by higher plants, is 

 represented in our compounds by 5-methoxy-p-toluquinone * 1 and pos- 

 sibly by fomecins A and B. 2 



Fomecins A and B are compounds isolated from culture liquids 

 of Fomes juniperinus. Both have the molecular formula C 8 H 8 5 . 

 Fomecin A has one acidic grouping. Its ultraviolet absorption spec- 

 trum (in 95% ethanol) shows maxima at 241 nut {E — 10,760) and 

 305 in/* {E = 14,260), maxima not typical of quinones. 3 When an 

 aqueous suspension of fomecin A was treated with S0 2 the crystals 

 dissolved, as would be expected on formation of a hydroquinone, but 

 the orange-red color was not discharged nor could a hydroquinone be 

 recovered. When the S0 2 was removed with nitrogen and the solution 

 somewhat concentrated, crystals of fomecin A (identified by ultraviolet 

 absorption spectrum and by analysis) were recovered. On the other 

 hand, it reacted with 2,4-dinitrophenylhydrazine to yield a mono- 

 2,4-dinitrophenylhydrazone, Ci4Hi 2 N 4 8 , and with amines to yield 

 deeply colored solutions which deposited colored crystalline deriva- 

 tives. The aniline derivative analyzed for C14H13NO4 (C 8 H 8 5 + 

 C c H 5 NH 2 -H 2 0). 



Fomecin B is isomeric with fomecin A (C 8 H 8 5 ). It has absorption 

 maxima in the ultraviolet at 262 mju, (E = ca. 20,000) and at 337 m/z, 

 (E = ca. 7000). Its behavior toward 2,4-dinitrophenylhydrazine and 

 amines is similar to that of fomecin A, but no crystalline derivatives 

 have been isolated. If the fomecins are quinoidal, they apparently 

 are not simple p-quinones. 



The compound 5-methoxy-p-toluquinone (I) was isolated from cul- 



* Unpublished work. 



