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By ROBERT GEORGE FARGHER and FKANK LEE PYMAN. THIS investigation was begun with the object of effecting the synthesis of purine derivatives by a method complementary to those which have been employed hitherto. In these, the pyrimidine nucleus is first built up and the glyoxaline ring closed subsequently. We proposed to prepare 4-aminoglyoxaline-5-carboxylic' acid,* condense it with cyanic acid, and eliminate water with t,he production of xanthine. Such a synthesis would be of interest in view of the suggestion that purine derivatives originate from histidine in the animal body (compare Hopkins, T., 1916, 109, 629). Although the starting material for the proposed synthesis, 4-aminoglyoxaline-5-carboxylic acid, was unknown, we did not anticipate that its preparation woald offer any serious difficulty. We have, however, so far failed t o obtain this substance, and now give an account of our attempts to prepare this and other aminosubstituted glyoxdines. An account of the investigation may be subdivided under three headings: first, the preparation of the glyoxalines and their carboxylic acids, which were required as starting materials ; second, the preparation and properties of nitroglyoxalines; and last, the preparation and properties of arylazoglyoxalines. * In glyoxalines containing a free imino-group, the 4-and 5-positions are equivalent.

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Emetine does not, therefore, contain a phenolic grouping as suggested by Keller (Zoc. cit.). The formation of gnaiacol in his experiments can be explained by either of two assumptions, namely : (1) that particill demethylation of the degrndation products has taken place, or (2) that the emetine and its methylation products employed contained cephaeline and its methylation proilucts as impurities. The second aswmptinn appears tlie more probable in view of Keller's statement (Toe. cit., 11. 701) that crude amorphous emetine hydrochloride, which contains "only a little ccphaeline," is suitable without further purification for the preparation of triniethylenictine di-iodide.