Pyridyl enamines and dienamines as models of mycobacterial pigments

Abstract

N,N'-Tetramethylformamidinium perchlorate and its higher vinylogue react with 4-picolylsodium to yield 4-(2-dimethylaminovinyl)pyridine (1) and l-dimethyl-amino-4-(4-pyridyl)buta-1,3-diene (3), and with 2-picolylsodium to yield the 2-pyridine isomers (2) and (4). The N.M.R. spectra and dissociation constants of these products are reported. The electronic spectra of the bases, their mono- and di-cations, and of some related compounds are described, and comparisons are drawn with coloured alkaloids which are produced by Mycobacterium tuberculosis in the presence of isonicotinoylhydrazide.