作者:Chatterjee, Ayon、Priyanka、Prabhu, N. Prakash、Padhi, Santosh Kumar
DOI:10.1021/acscatal.4c04000
日期:——
(DHR) is an effective direct C–C bond ligation transformation that enables the synthesis of β-nitroalcohols having two contiguous chiral centers. Despite significant applications of opticallyactive β-nitroalcohol diastereomers as key chiral intermediates for the synthesis of important pharmaceuticals and biologically active molecules, the biocatalytic asymmetric Henry reaction remains underdeveloped
非对映选择性亨利反应 (DHR) 是一种有效的直接 C-C 键连接转化,能够合成具有两个连续手性中心的 β-硝基醇。尽管光学活性β-硝基醇非对映异构体作为合成重要药物和生物活性分子的关键手性中间体具有重要应用,但生物催化不对称亨利反应仍然不发达。在这里,我们发现具有单氨基酸取代 Y14C 和 Y14A的拟南芥羟基腈裂合酶 ( At HNL) 变体使混杂的 DHR 具有对不同醛和硝基烷烃的广泛合成范围以及高对映和非对映选择性(高达 >99% ee) , >99% de , >99% ic , 和 ∼3470 总周转数)在多种抗(1 R ,2 S )-β-硝基醇的生产中。 Y14C 在立体选择性硝基乙烷加成苯甲醛方面的催化效率比野生型显着提高了 250 倍以上。使用现成的苯甲醛和硝基乙烷说明了克级生物催化作用,然后对产物进行一步化学还原,以制备L-去甲麻黄碱,这是一种治疗剂,其ee和de含量 >
Urea/Transition-Metal Cooperative Catalyst for anti-Selective Asymmetric Nitroaldol Reactions
作者:Kai Lang、Jongwoo Park、Sukwon Hong
DOI:10.1002/anie.201107785
日期:2012.2.13
A cooperativecatalyst that features urea H‐bonding and a cobalt center was developed for anti‐selective asymmetric Henry reactions (see scheme). The H‐bonds of urea play a crucial role in the improvement in yield (from 30 % to 84 %), enantioselectivity (from 78 % to 96 %), and anti diastereoselectivity (from 3:1 to 48:1). A short synthesis of (1R,2S)‐methoxamine hydrochloride was also accomplished