Highly enantioselective Darzens-type epoxidation of diazoesters with glyoxal derivatives was accomplished using a chiral boron–Lewis acid catalyst, which facilitated asymmetric synthesis of trisubstituted α,β-epoxy esters. In the presence of a chiral oxazaborolidinium ion catalyst, the reaction proceeded in high yield (up to 99 %) with excellent enantio- and diastereoselectivity (up to >99 % ee and
Synthesis of Rhodium Complexes with Chiral Diene Ligands via Diastereoselective Coordination and Their Application in the Asymmetric Insertion of Diazo Compounds into E−H Bonds
作者:Nikita M. Ankudinov、Denis A. Chusov、Yulia V. Nelyubina、Dmitry S. Perekalin
DOI:10.1002/anie.202105179
日期:2021.8.16
A new method for the synthesis of chiral diene rhodium catalysts is introduced. The readily available racemic tetrafluorobenzobarrelene complexes [(R2-TFB)RhCl]2 were separated into two enantiomers via selective coordination of one of them with the auxiliary S-salicyl-oxazoline ligand. One of the resulting chiral complexes with an exceptionally bulky diene ligand [(R,R-iPr2-TFB)RhCl]2 was an efficient
介绍了一种合成手性二烯铑催化剂的新方法。容易获得的外消旋四氟苯并二甲苯配合物 [(R 2 -TFB)RhCl] 2通过其中之一与辅助S-水杨基-恶唑啉配体的选择性配位被分离成两种对映异构体。所得手性配合物之一具有异常庞大的二烯配体 [( R , R - i Pr 2 -TFB)RhCl] 2是重氮酯不对称插入 B-H 和 Si-H 键的有效催化剂,得到官能化的有机硼烷和硅烷具有高产率 (79–97 %) 和对映体纯度 (87–98 % ee)。通过 DFT 计算预测了辅助配体分离的立体选择性和催化反应的立体选择性。
Cu(I)/Chiral Bisoxazoline-Catalyzed Enantioselective Sommelet–Hauser Rearrangement of Sulfonium Ylides
作者:Shu-Sen Li、Jianbo Wang
DOI:10.1021/acs.joc.0c01590
日期:2020.10.2
asymmetric thia-Sommelet–Hauser rearrangement of sulfonium ylides remains a great challenge due to its multistep reaction mechanism involving metal carbene formation, proton transfer, and [2,3]-sigmatropic rearrangement. In particular, the key problem of such reactions is the differentiation of the enantiotopic lone pair electrons of sulfur, which generates the sulfonium ylide intermediate bearing chirality
new and simple one-pot procedure for the palladium-catalyzedintermolecular α-arylation of esters is described. A number of esters can be functionalized with a wide range of aryl bromides using Pd(OAc)2 or Pd2(dba)3 and bulky electron-rich o-biphenyl phosphines 1−3. Under the reaction conditions, using LiHMDS as base, α-arylation proceeds at roomtemperature or at 80 °C with very good yields and high
[EN] ORAL COMPLEMENT FACTOR D INHIBITORS<br/>[FR] INHIBITEURS DE FACTEUR D DU COMPLÉMENT ORAL
申请人:BIOCRYST PHARM INC
公开号:WO2021072156A1
公开(公告)日:2021-04-15
Disclosed are compounds of formula (I)-(IV), and pharmaceutically acceptable salts thereof, which are inhibitors of the complement system. Also provided are pharmaceutical compositions comprising such a compound, and methods of using the compounds and compositions in the treatment or prevention of a disease or condition characterized by aberrant complement system activity.