Ni(II) Bis(oxazoline)-Catalyzed Enantioselective Syn Aldol Reactions of <i>N</i>-Propionylthiazolidinethiones in the Presence of Silyl Triflates
作者:David A. Evans、C. Wade Downey、Jed L. Hubbs
DOI:10.1021/ja035509j
日期:2003.7.1
enantioselective aldol reaction of N-propionylthiazolidinethione and representative aldehydes is disclosed. The reaction is catalyzed by [Ni(S,S)-t-BuBox](Otf)2. Enolization is effected by 2,6-lutidine, and TMSOTf facilitates catalyst turnover. Syn diastereoselectivities range from 88:12 to 97:3, and enantioselectivities are 90% or greater. Both aromatic and enolizable aliphatic aldehydes are included within
Understanding Programming of Fungal Iterative Polyketide Synthases: The Biochemical Basis for Regioselectivity by the Methyltransferase Domain in the Lovastatin Megasynthase
作者:Ralph A. Cacho、Justin Thuss、Wei Xu、Randy Sanichar、Zhizeng Gao、Allison Nguyen、John C. Vederas、Yi Tang
DOI:10.1021/jacs.5b11814
日期:2015.12.23
Highly reducingpolyketidesynthases (HR-PKSs) from fungi synthesize complex natural products using a single set of domains in a highly programmed, iterative fashion. The most enigmatic feature of HR-PKSs is how tailoring domains function selectively during different iterations of chainelongation to afford structural diversity. Using the lovastatin nonaketide synthase LovB as a model system and a