Characterization of the purified components of a new homologous series of alpha-mycolic acids from Mycobacterium tuberculosis H37Ra.

Homologous series of alpha-mycolic acids from Mycobacterium tuberculosis H37Ra were separated according to size as their p-bromophenacyl ester by bonded C18 reverse-phase, high performance liquid chromatography. Mass spectrometry of the prominent components separated by high performance liquid chromatography gave relatively simple spectra and showed a series of components differing by 28 atomic mass units. A total of different structures were identified. The structures were established as follow: (formula see text) where a = 17, 18, 19; b = 10; c = 15, 17, 19, 21; and d = 21, 23. The C76 and C78 acids contained some C24 alpha-branch acid (d - 21), whereas the C80 and C82 acids contained some a = 19 acids. Several new homologous series were revealed.