Studies on nitrogen metabolism using carbon-13 NMR spectroscopy. 6. Biosynthesis of sarubicin A. Synthesis and incorporation of 6-hydroxy[13CO15NH2]anthranilamide
作者:Steven J. Gould、Rodney L. Eisenberg
DOI:10.1021/jo00023a036
日期:1991.11
We have previously demonstrated that 6-hydroxyanthranilic acid (3) is specifically incorporated into sarubicin A (1) by Streptomyces helicus. 6-Hydroxyanthranilamide (4) has now been synthesized in five steps from m-anisidine in a manner that allowed efficient introduction of isotope labels to prepare [(CONH2)-C-13-N-15]-4a. A new synthesis of 3 from m-anisidine has also been developed. 4a was fed to S. helicus, and a 1.29% incorporation into 1b was obtained. Examination of the C-13 NMR spectrum of 1b revealed predominantly intact incorporation, with a minor amount of 4a (0.13%) first undergoing in vivo hydrolysis to the corresponding acid. Thus, carboxamide formation is the next step in the biosynthesis of 1.