Alkaloids of the Australian Rutaceae: Melicope fareana. IV. Some Reactions of 1-Methyl-4-quinolone-3-carboxyic Acid, a Degradation Product of the Alkaloids

Abstract

Melicopine, melicopidine, and melicopicine are each oxidized by nitric acid to the same acid, C₁₁H₉O₃N. Decarboxylation gives 1-methyl-4-quinolone (I) and the acid is shown to be 1-methyl-4-quinolone-3-carboxylic acid (II). The 3- and 6- mononitro-, 3,6-dinitro-, and 2-hydroxy-3,6-dinitro- derivatives of 1-methyl-4-quinolone have been prepared and the orientation of the substituents established by oxidation of the hydroxydinitro- compound to 5-nitro-N-methylanthranilic acid. 1-Methy1-4-quinolone-3-carboxylic acid is readily converted to a tetrahydro- derivative. The carboxyl groups in II and in the tetrahydro- acid are reduced by zinc and hydrochloric acid to methyl groups.