前面的两篇论文[Powers,VM,Koo,CW,Kenyon,GL,Gerlt,JA,和Kozarich,JW(1991)生物化学(本期第一篇,共三篇);Neidhart,DJ,Howell,PL,Petsko,GA,Powers,VM,Li,R.,Kenyon,GL,&Gerlt,JA(1991)Biochemistry(本期三期的第二篇论文)]建议扁桃体的活性位点消旋酶(MR)包含两种截然不同的通用酸/碱催化剂:Lys 166,其从(S)-扁桃酸酯中提取α-质子; His 297,其从(R)-扁桃酸酯中提取α-质子。在本文中,我们报告了MR突变体的特性,其中His 297通过定点诱变(H297N)已转化为天冬酰胺。H297N的结构可通过以2.2-A的分辨率进行分子置换来解决,表明该置换没有构象变化。不出所料,H297N没有可检测的MR活性。然而,H297N催化从外消旋对-(溴甲基)扁
A chiral spirobifluorene-based bis(salen) zinc(<scp>ii</scp>) receptor towards highly enantioselective binding of chiral carboxylates
作者:Sk Asif Ikbal、Yoko Sakata、Shigehisa Akine
DOI:10.1039/d1dt00218j
日期:——
We have designed a newchiral receptor based on two salen zinc(II) complex units connected with a spirobifluorene framework. The chiral receptor is proven to enantioselectively bind chiral carboxylate guests and the differences between the binding constants of enantiomeric guests were up to more than one order of magnitude.
different anion (acetate, benzoate, fluoride, and chloride) have been studied by 1H‐NMR titration and have been observed in the case of 4 is a selective receptor for acetate. The theoretical calculation M06/6‐311+G(d,p) helped us explain the binding properties observed. The most interesting observation is that this calculated structure is consistent with expected, based on the concept of allylic 1,3‐strain
Preorganized Homochiral Pyrrole‐Based Receptors that Display Enantioselective Anion Binding
作者:Johannes Karges、Seth M. Cohen
DOI:10.1002/ejoc.202101346
日期:2022.4.27
Herein, a series of tris(pyrrolamide) receptors for anion recognition is presented. The receptors were able to bind to a variety of anions with good affinity, and homochiralreceptors produced a 1.6-fold greater affinity for (S)-(+)-mandelate over (R)-(−)-mandelate, demonstrating the ability to differentiate between these enantiomeric anions.
在此,提出了一系列用于阴离子识别的三(吡咯酰胺)受体。这些受体能够以良好的亲和力与多种阴离子结合,并且纯手性受体对 ( S )-(+)-扁桃酸的亲和力是 ( R )-(−)-扁桃酸的 1.6 倍,这表明其能够区分这些对映体阴离子。
The invention is directed to 5,6-dihydro-1H-pyridin-2-one compounds and pharmaceutical compositions containing such compounds that are useful in treating infections by hepatitis C virus.