1517-68-6Relevant articles and documents
Discovery and Redesign of a Family VIII Carboxylesterase with High (S)-Selectivity toward Chiral sec-Alcohols
Park, Areum,Park, Seongsoon
, p. 2397 - 2402 (2022/02/17)
Highly enantioselective lipase has been widely utilized in the preparation of versatile enantiopure chiral sec-alcohols through kinetic or dynamic kinetic resolution. Lipase is intrinsically (R)-selective, and it is difficult to obtain (S)-selective lipase. Recent crystal structures of a family VIII carboxylesterase have revealed that the spatial array of its catalytic triad is the mirror image of that of lipase but with a catalytic triad that is distinct from lipase. We, therefore, hypothesized that the family VIII carboxylesterase may exhibit (S)-enantioselectivity toward sec-alcohols similar to (S)-selective serine protease, whose catalytic triad is also spatially arrayed as its mirror image. In this study, a homologous enzyme (carboxylesterase from Proteobacteria bacterium SG_bin9, PBE) of a known family VIII carboxylesterase (pdb code: 4IVK) was prepared, which showed not only moderate (S)-selectivity toward sec-alcohols such as 3-butyn-2-ol and 1-phenylethyl alcohol but also (R)-selectivity toward particular sec-alcohols among the substrates explored. Furthermore, the (S)-selectivity of PBE has been significantly improved by rational redesign based on molecular modeling. Molecular modeling identified a binding pocket composed of Ser381, Ala383, and Arg408 for the methyl substituent of (R)-1-phenylethyl acetate and suggested that larger residues may increase the enantioselectivity by interfering with the binding of the slow-reacting enantiomer. As predicted, substituting Ser381with larger residues (Phe, Tyr, and Trp) significantly improved the (S)-selectivity of PBE toward all sec-alcohols explored, even the substrates toward which the wild-type PBE exhibits (R)-selectivity. For instance, the enantioselectivity toward 3-butyn-2-ol and 1-phenylethyl alcohol was improved from E = 5.5 and 36.1 to E = 2001 and 882, respectively, by single mutagenesis (S381F).
C3 The symmetry contains a chiral ligand H3L of an amide bond. Preparation method and application
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Paragraph 0092-0100, (2021/09/08)
The invention discloses C. 3 Chiral ligand H with symmetric amide bond3 L Relates to the technical field of material chemistry and chiral chemistry. The invention further provides the chiral ligand H. 3 L Preparation method and application thereof. The present invention has the advantage that the chiral ligand H of the present invention is a chiral ligand. 3 The L has a higher C. 3 The symmetric and flexible amide group enables coordination of the lanthanide metal ions with high coordination number and high oxygen affinity to be assembled into a novel structure-structure lanthanide metal chiral porous coordination cage. Moreover, the abundant chiral amide groups and amino acid residues on the ligand framework can be directly introduced into the synthesized lanthanide metal chiral porous coordination cage, thereby being beneficial to generating multiple chiral recognition sites and unique chiral microenvironments which mimic the biological enzyme binding pocket and further realize the purpose of high enantioselectivity separation of a series of chiral small molecule compounds.
Method for synthesizing chiral secondary alcohol compound
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Paragraph 0038-0041; 0156-0159, (2021/05/29)
The invention discloses a method for synthesizing a chiral secondary alcohol compound. The method comprises the following step of: reacting a ketone compound in an aprotic organic solvent at room temperature and inert gas atmosphere under the action of a chiral cobalt catalyst and an activating agent by taking a combination of bis(pinacolato)diboron and alcohol or water as a reducing agent to obtain the chiral secondary alcohol compound. According to the method disclosed by the invention, a combination of pinacol diborate and alcohol or water which are cheap, stable and easy to obtain is taken as a reducing agent, and a ketone compound is efficiently reduced to synthesize a corresponding chiral secondary alcohol compound in an aprotic organic solvent under the action of a chiral cobalt catalyst; in a chiral cobalt catalyst adopted by the method, when a chiral ligand is PAOR, an activating agent is NaBHEt3 or NaOtBu and an adopted raw material is aromatic ketone, the yield is 80% or above, and the optical purity is 90% or above; and when the adopted raw material is alkane ketone, the yield can reach 70% or above, and the optical purity can reach 80% or above.