202 SCIENCE PROGRESS 



the tautomeric form containing bivalent carbon H — C — OH. 

 This reacts with potassium nitrite 



H— C— OH H— C— OH 



H— C— OH+0=N— OK -> II -> li +0 



0=N— OK NOK 



Potassium salt of 

 fonnhydroxamic acid. 



Now in all the reactions between formhydroxamic acid and 

 activated formaldehyde oxygen is liberated, as evidenced by 

 the oxidation of some of the formaldehyde to formic acid, a 

 reaction which does not occur when aqueous solutions of 

 the aldehyde alone are exposed to ultra-violet light. In this 

 connection the presence of an enzyme in leaves which has the 

 power of accelerating the loss of oxygen b}^ various compounds 

 is suggestive. As the oxygen must come from the formhy- 

 droxamic acid, this compound at the moment of reaction is 



H— C— OH 

 represented as || and can then combine with one 



NH 

 molecule of activated formaldehyde to form the ring compound 



HO . CH— CH .OH 



\ / which on rearrangement would give glycine 



NH 

 CH2NH2 . COOH. The methylene group of glycine may react 

 with more activated formaldehyde to give homologues. Such 

 a synthesis postulates that only a-amino-acids would be formed, 

 which is invariably the case in phytosynthesis. If the form- 

 hydroxamic acid combines with three or four molecules of the 

 aldehyde the compounds 



CH.OH 

 HO . CH— CH .OH / \ 



I I OH . CH CH . OH 



HO . CH CH . OH and | | 



\/ HO . CH CH . OH 



NH \ / 



NH 



would be formed, which by loss of oxygen and water would 

 give pyrrolidine or pyrrole and piperidine or pyridine com- 

 pounds respectively. Further combination of pyrrole and 

 pyridine with activated formaldehyde and loss of oxygen and 

 water would give rise to indoles, quinolines, and isoquinolines. 

 Two molecules of formhydroxamic acid, by condensing with 

 one molecule of the activated aldehyde, would give a compound 

 (i) which by loss of oxygen and water gives glyoxaline, which 

 would condense further with two molecules of formhydroxamic 

 acid to give (ii) a xanthine derivative. 



