NosN, a Radical <i>S</i>-Adenosylmethionine Methylase, Catalyzes Both C1 Transfer and Formation of the Ester Linkage of the Side-Ring System during the Biosynthesis of Nosiheptide
作者:Joseph W. LaMattina、Bo Wang、Edward D. Badding、Lauren K. Gadsby、Tyler L. Grove、Squire J. Booker
DOI:10.1021/jacs.7b08492
日期:2017.12.6
backbone via ester and thioester linkages, respectively. Herein, we show that NosN, a predicted class C radical S-adenosylmethionine (SAM) methylase, catalyzes both the transfer of a C1 unit from SAM to 3-methylindolic acid linked to Cys8 of a synthetic substrate surrogate as well as the formation of the ester linkage between Glu6 and the nascent C4 methylene moiety of DMIA. In contrast to previous studies
One-Pot Enantiomeric Synthesis of Thiazole-Containing Amino Acids: Total Synthesis of Venturamides A and B
作者:Yi Liu、Peng He、Yang Zhang、Xiangyu Zhang、Jun Liu、Yuguo Du
DOI:10.1021/acs.joc.8b00244
日期:2018.4.6
thiazole-containing amino acid (TCAA) has been established via a cascade disulfide cleavage/thiocarbonylation/intramolecular Staudinger reduction/aza-Wittig/oxidation reaction. Starting from the commercially available amino acid building blocks, a number of TCAAs were prepared in good yields and with excellent optical purities. This method bears features of mildreactionconditions, wide substrate adaptability
Intramolecular aza-Wittig ring closures were applied to synthesize thiazolines, oxazolines, and imidazolines from β-azido thioester, ester, and amide precursors. The cyclization precursors were obtained from amino acid derivatives. Optimized conditions for diazo transfer with a fast rate and racemization suppression, (thio)esterification, and amide coupling reactions are described. The ring closure reaction can