Maytanprine and maytanbutine, new antileukaemic ansa macrolides from Maytenus buchananii

Characterization of Decomposition Products of Maytansine

“…The major decomposition product, compound A, was compared by analytical TLC with a series of known maytansinoids available through previous work.19*20 Compound A was found to exhibit an Rf value in several solvent systems identical to that of maysine (2). The 'H NMR spectra of A and 2 were compared and also found to be identical.…”

“…The major decomposition product was found to be maysine (2), which results from the hydrolytic elimination of the C-3 ester of 1. The facile formation of 2 is not unexpected given the mild reaction conditions required to accomplish this reaction in the laboratory. 6 The fact that-2 is the major decomposition product suggests that it may also be the initial metabolite of…”

Recent Developments in the Maytansinoid Antitumor Agents

“…52) More recently (1989), maytansine was tested in NCI's panel of 60 human tumor cell lines 53) and showed patterns of inhibition indicative of tubulin-interactive compounds (G. M. Cragg, personal communication). Closely related compounds, such as maytanprine and maytanbutine, but not maytansinol, showed a similar activity spectrum and potency as maytansine, 52) as did normaytansine.…”

Microbiological Assays and Bioautography of Maytansine and Its Homologues

“…Maytansine and its homologues, maytanbutine and maytanprine, are new ansa macrolides isolated from tropical plants of the genus Maytanus by S. Kupchan et al (1,2). Maytansine was highly active against experimental tumors in mice and rats (1).…”

“…Chromatography. Ethyl acetate was a suitable chromatographic system for differentiating maytansine from its homologue on silica gel GF (250 Mm) and using ultraviolet light for detection (2).…”