Vicinal Diboronates in High Enantiomeric Purity through Tandem Site-Selective NHC−Cu-Catalyzed Boron−Copper Additions to Terminal Alkynes
摘要:
A Cu-catalyzed protocol for conversion of terminal alkynes to enantiomerically enriched diboronates is reported. In a single vessel, a site-selective hydroboration of an alkyne leads to the corresponding terminal vinylboronate, which undergoes a second site-selective and enantioselective hydroboration. Reactions proceed in the presence of 2 equiv of commercially available bis(pinacolato)diboron [B-2(pin)(2)] and 5-7.5 mol % loading of a chiral bidentate imidazolinium salt, affording diboronates in 60-93% yield and up to 97.5:2.5 enantiomeric ratio (er). The enantiomerically enriched products can be functionalized to afford an assortment of versatile organic molecules. Enynes are converted to unsaturated diboronates with high chemo- (>98% reaction of alkyne; <2% at alkene) and enantioselectivity (e.g., 94.5:5.5 er).
Vicinal Diboronates in High Enantiomeric Purity through Tandem Site-Selective NHC−Cu-Catalyzed Boron−Copper Additions to Terminal Alkynes
摘要:
A Cu-catalyzed protocol for conversion of terminal alkynes to enantiomerically enriched diboronates is reported. In a single vessel, a site-selective hydroboration of an alkyne leads to the corresponding terminal vinylboronate, which undergoes a second site-selective and enantioselective hydroboration. Reactions proceed in the presence of 2 equiv of commercially available bis(pinacolato)diboron [B-2(pin)(2)] and 5-7.5 mol % loading of a chiral bidentate imidazolinium salt, affording diboronates in 60-93% yield and up to 97.5:2.5 enantiomeric ratio (er). The enantiomerically enriched products can be functionalized to afford an assortment of versatile organic molecules. Enynes are converted to unsaturated diboronates with high chemo- (>98% reaction of alkyne; <2% at alkene) and enantioselectivity (e.g., 94.5:5.5 er).
Structure-Guided Regulation in the Enantioselectivity of an Epoxide Hydrolase to Produce Enantiomeric Monosubstituted Epoxides and Vicinal Diols via Kinetic Resolution
Structure-guided microtuning of an Aspergillus usamii epoxide hydrolase was executed. One mutant, A214C/A250I, displayed a 12.6-fold enhanced enantiomeric ratio (E = 202) toward rac-styrene oxide, achieving its nearly perfect kinetic resolution at 0.8 M in pure water or 1.6 M in n-hexanol/water. Several other beneficial mutants also displayed significantly improved E values, offering promising biocatalysts
对Aspergillus usamii环氧水解酶进行了结构引导的微调。一种突变体 A214C/A250I对消旋-氧化苯乙烯的对映体比 ( E = 202)提高了 12.6 倍,在纯水中 0.8 M 或正己醇/水中 1.6 M 时实现了近乎完美的动力学分辨率。其他一些有益的突变体也显示出显着提高的E值,为获得 19 种结构多样的手性单取代环氧化物(97.1 – ≥ 99% ee s)和邻二醇(56.2–98.0% ee p)提供了有希望的生物催化剂,并且产率很高。
FORMATION OF MACROMOLECULES USING ITERATIVE GROWTH AND RELATED COMPOUNDS
申请人:Massachusetts Institute of Technology
公开号:US20160272623A1
公开(公告)日:2016-09-22
In some embodiments, macromolecules and related methods are provided. In some embodiments, an iterative growth process may be used to form a macromolecule comprising one or more repeat units comprising a functionalizable pendant group, with precise control over mass, length, backbone sequence, pendant group sequence, and/or stereochemistry, amongst other features. Macromolecules (e.g., non-natural macromolecules) form from the iterative growth process, described herein, may be used for a wide variety of applications, including the delivery of active agents.
The invention relates to N-substituted azaindolyl compounds of Formula I with anti-cancer and/or anti-inflammatory activity and more specifically to N-substituted azaindolyl compounds which inhibit MEK kinase activity. The invention provides compositions and methods useful for inhibiting abnormal cell growth or treating a hyperproliferative disorder, or treating an inflammatory disease in a mammal. The invention also relates to methods of using the compounds for in vitro, in situ, and in vivo diagnosis or treatment of mammalian cells, or associated pathological conditions.
PROCESS FOR THE PREPARATION OF (S)-4-FLUOROMETHYL-DIHYDRO-FURAN-2-ONE
申请人:Zutter Ulrich
公开号:US20080108816A1
公开(公告)日:2008-05-08
The present invention relates to a process of the preparation of (S)-4-fluoromethyl-dihydro-furan-2-one of the formula
by employing a dialkylmalonate of the formula
wherein R
1b
is lower alkyl, and the use of this process for the manufacture of DPP-IV inhibitors that are useful for the treatment and/or prophylaxis of diseases such as diabetes.
The invention relates to bicyclic heterocycles of formulae I and II with anti-cancer and/or anti-inflammatory activity and more specifically with MEK kinase inhibitory activity. The invention provides compositions and methods useful for inhibiting abnormal cell growth, treating a hyperproliferative disorder, or treating an inflammatory disease in a mammal. The invention also relates to methods of using the compounds for in vitro, in situ, and in vivo diagnosis or treatment of mammalian cells, or associated pathological conditions.