Synthesis of some thiophen compounds, with notes on the metabolism of thienyl carboxylic acid and of thienylalanine, and on the physiological action of thienylethylamine.

Abstract

(1) In a brief introduction, the physical and chemical properties of benzene and of thiophen are compared and contrasted. A review of what is known of the physiological behaviour of thiophen and its compounds is given.(2) The preparation of thiophen by a method similar to that of Steinkopf is described. The efficiency attained was comparable with that reported by Steinkopf in his earlier experiments. The method was found to be satisfactory for the preparation of large quantities of thiophen.(3) The results are described of a number of experiments in which different methods for the preparation of -thiophenaldehyde were investigated. A full description of the most satisfactory method is given.(4) The syntheses of the following hitherto undescribed derivatives of thiophen are described: - 1. Amino methyl a- thienyl ketone hydrochloride. 2. Thienyl propionic acid. 3. Thienyl propioizarnide. 4-6. a-Thienyl- 13 -ethylamine; hydrochloride, quaternary methiodide. 7. 3:4-methylene dioxy-benzal thienyl ethylamine. 8. Fórmyl thienylethylamine. 9. Azolactone of a-thienyl-a -benzoyl amino acrylic acid. 10. a-Thienyl- a-benzoylamino acrylic acid. 11. a-Thienyl- a-benzoylamino propionic acid. 12. a-Thenal hydantoin; 13. Acetyl derivative. 14. a-Thenyl hydantoin. 15. a-Thienyl-ß -alanine.Most of these have been analysed and characterised.(5) A. note on the results of pharmacological tests of thienyl- ethylamine is given. The physiological action is exactly similar to that of phenylethylamine.Results of a preliminary experiment on the metabolism of thienylalanine are reported. There are indications from this experiment that thienylalanine does not behave in the same way as phenyl - alanine . No definite conclusions, however, can be drawn.