No abstract

Direct Synthesis of Ternary Iminium Salts 3021 the precipitate became sticky and decomposed. The yield of chelate diazonium fluoroborate N was 0.51 g. (55.0%). The infrared spectrum exhibited a sharp peak at 2200 cm.-1 (diazonium ion18) and a peak at 1050 cm.-1 (fluoroborate anion19). The diazonium salt melted at 165°with decomposition.

The principal biotransformation product of taxol was found to be identical for human hepatic microsomes, human liver slices, and patient bile samples. We have isolated this metabolite from the bile of a patient given taxol, and we report its structure and its cytotoxicity relative to taxol. The NMR and SIMS data presented here indicate that, in humans, taxol is regiospecifically hydroxylated at the 6-position on the taxane ring and that this hydroxyl is stereospecifically placed trans to the hydroxyl at position 7, yielding 6 alpha-hydroxytaxol. This metabolite is apparently not formed in rats. Tests of the growth inhibition potential of 6 alpha-hydroxytaxol versus taxol in two human tumor cell lines showed that the metabolite was approximately 30-fold less cytotoxic than taxol. Thus the cytochrome P-450-mediated biotransformation of taxol to 6 alpha-hydroxytaxol can be classified as a detoxification reaction.

Metabolites, alternariol (AOH) and alternariol monomethyl ether (AME), were isolated from discolored, weathered grain sorghum that had been invaded by Alternaría sp. These compounds were found in 1973 spring-harvested (overwintered) sorghum and in weathered sorghum har-vested in the fall of 1973. Thin-layer chromatograms and fluorescence of AME and zearalenone are similar. Means of avoiding confusion of AME, AOH, and other fluorescent substances in grain sorghum with zearalenone and aflatoxin are discussed.

No abstract