Synthesis and enzyme-catalysed reductions of 2-oxo acids with oxygen containing side-chains
作者:Gurdip Bhalay、Sarah Clough、Lee McLaren、Andrew Sutherland、Christine L. Willis
DOI:10.1039/a909677i
日期:——
A series of novel 2-oxo esters with protected alcohols at the 3-, 4-, 5-, 6- and 7-positions has been prepared either via coupling of an aldehyde with an organometallic reagent (Zn, In or Cr) or via a one-carbon homologation of the precursor acid. A one-pot dual enzyme system was used to convert the simpler 2-oxo acids (with a single MOM ether at either C-3 or C-4) into enantiopure protected 2,3- and 2,4-dihydroxy acids in good yields, but in the cases of the more complex trisubstituted substrates, significant decomposition occurred. Biotransformations have proved valuable for the enantioselective synthesis of protected 2,6,7-trihydroxyhept-3-enoic acids.
一系列在3-、4-、5-、6-和7-位带有保护醇的新型2-氧代酯,可以通过醛与有机金属试剂(锌、铟或铬)的耦合反应或通过前驱酸的一碳同系化制备。一种一步法双酶系统被用于将简单的2-氧代酸(在C-3或C-4位上带有单一的MOM醚)转化为高对映纯度的保护2,3-和2,4-二羟基酸,产率良好,但在更复杂的三取代底物情况下,发生了显著的分解。生物转化已被证明在保护的2,6,7-三羟基-3-烯酸的对映选择性合成中具有价值。