4-L-methylaminoethylglyoxaline / by Robert George Fargher and Frank Lee Pyman.

  • Fargher, Robert George.
Date:
[1921?]
Catalogue details

Licence: In copyright

Credit: 4-L-methylaminoethylglyoxaline / by Robert George Fargher and Frank Lee Pyman. Source: Wellcome Collection.

    1/8
    tH- LXXVIII.—4 -/3-Meihyiammoethylglyoxaline. By Robert George Fargher and Frank Lee Pyman. The isolation of 4-f3-aminoethylglyoxaline from ergot, and the recognition of its importance as an intense stimulant of plain muscle, have led in recent years to the synthesis, not only of the substance itself, but also of a number of related compounds, the examination of which has indicated the presence of an optimum side-chain of two carbon atoms between the cyclic system and the amino-group (Ewins, T., 1911, 99, 2052; Pyman, ibid., 2172; 1916, 109, 186). As the same optimum condition obtains in the sympathomimetic amines (Barger and Dale, J. Physiol., 1910, 41, 19), it was deemed of interest, in view of the importance of the A-alkyl substituent in that series, to prepare 4-$-methylamino- ethylglyoxaline and to compare its physiological action with that of the naturally occurring base. Considerable difficulty has been experienced in devising a prac¬ ticable mode of preparation. The methods employed by Barger and his collaborators (Walpole, T., 1910, 97, 941; Barger and Ewins, ibid., 22, 53) for the synthesis of the analogously substi¬ tuted p-phenylethylmethylamines were inapplicable, methylation of an acyl derivative of 4-p-aminoethylglyoxaline, for example, because of the readiness with which glyoxaiines combine with alkyl esters, and syntheses dependent on 4-{3-hydroxyethylglyox - aline or glyoxaline-4-acetaldehyde owing to the lack of satisfactory methods for the preparation of these substances. Eventually, recourse was made to the preparation of &\-aL-methyl- amino-p-glyoxaline-4-propionic acid (XI) by the interaction of d/-a-chloro-P-glyoxaline-4-propionic acid (I) and 40 per cent.