A5084642068- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Carbohydrate Chemistry and Synthesis
- Glycosylation and Glycoproteins Research
- Crystallography and molecular interactions
- Phytochemistry and Bioactive Compounds
- Steroid Chemistry and Biochemistry
- Synthetic Organic Chemistry Methods
- Phytochemical Studies and Bioactivities
- Marine Sponges and Natural Products
- Enzyme function and inhibition
- Asymmetric Synthesis and Catalysis
- Parkinson's Disease Mechanisms and Treatments
- Sulfur-Based Synthesis Techniques
- Estrogen and related hormone effects
- Catalytic C–H Functionalization Methods
- Enzyme Catalysis and Immobilization
- Radical Photochemical Reactions
- Microbial Natural Products and Biosynthesis
- Computational Drug Discovery Methods
- Chemical Synthesis and Analysis
- Fluorine in Organic Chemistry
- Metalloenzymes and iron-sulfur proteins
- Metal complexes synthesis and properties
- Biotechnology and Related Fields
Merck & Co., Inc., Rahway, NJ, USA (United States)
2020-2024
University of Michigan
2013-2019
Ann Arbor Center for Independent Living
2014-2016
William & Mary
2013
Williams (United States)
2013
Cambridge Crystallographic Data Centre
2013
In control: A chiral phosphoric acid catalyst significantly enhances or completely overrides the inherent regioselective acetalization profiles exhibited by monosaccharide-derived 1,2-diol substrates. This study represents first example of chiral-catalyst-directed regio- and enantioselective intermolecular acetalizations, which are complementary to existing methods for substrate-controlled functionalization polyols.
A new scalable enantioselective approach to functionalized oxygenated steroids is described. This strategy based on chiral bis(oxazoline) copper(II) complex-catalyzed and diastereoselective Michael reactions of cyclic ketoesters enones install vicinal quaternary tertiary stereocenters. In addition, the utility salts as highly active catalysts for traditionally unreactive β,β′-enones substituted β,β′-ketoesters that results in unprecedented adducts containing all-carbon centers also...
The expedient and scalable approach to cardiotonic steroids carrying oxygenation at the C11- C19-positions has been developed applied total asymmetric synthesis of 19-hydroxysarmentogenin trewianin aglycone as well assembly panogenin core. This new features enantioselective organocatalytic oxidation an aldehyde, diastereoselective Cu(OTf)2-catalyzed Michael reaction/tandem aldol cyclizations, one-pot reduction/transposition reactions allowing a rapid (7 linear steps) functionalized...
A Cu(II)-catalyzed diastereoselective Michael/aldol cascade approach is used to accomplish concise total syntheses of cardiotonic steroids with varying degrees oxygenation including cardenolides ouabagenin, sarmentologenin, 19-hydroxysarmentogenin, and 5-epi-panogenin. These enabled the subsequent structure activity relationship (SAR) studies on 37 synthetic natural elucidate effect oxygenation, stereochemistry, C3-glycosylation, C17-heterocyclic ring. Based this parallel evaluation their...
The application of bicyclo[1.1.1]pentanes (BCPs) as phenyl bioisosteres has garnered significant attention, these structural motifs can improve the physiochemical profiles drug candidates. Despite potential using 1-bicyclo[1.1.1]pentylpyrazoles (BCPPs) 1-phenylpyrazole bioisosteres, this area remains underexplored because relative lack reliable synthetic methods for preparation BCPPs. Herein we address gap and report development novel scalable routes to generate a host
Inhibition of leucine-rich repeat kinase 2 is a genetically supported mechanism for the treatment Parkinson's disease. We previously disclosed discovery an indazole series lead that demonstrated both safety and translational risks. The risks were hypothesized to be unknown origin, so structural diversity in subsequent chemical matter was prioritized. identified due low brain Kp
Die inhärente Regioselektivät der Acetalisierung Monosaccharid-abgeleiteter 1,2-Diole kann durch einen chiralen Phosphorsäurekatalysator (siehe Schema) verstärkt oder vollständig aufgehoben werden. Diese ersten katalysatorgesteuerten regio- und enantioselektiven intermolekularen Acetalisierungen ergänzen bekannte Methoden zur substratgesteuerten Funktionalisierung von Polyolen.
In the presence of Cd(ClO4)2 and a base, new mixed N,S-donor alkylthiolate ligand supported both carbonate formation from atmospheric CO2 self-assembly novel bicapped puckered (CdS)6 molecular wheel. The remarkable stability complex was demonstrated by slow intermolecular exchange on (2)J(HH) J((111/113)Cd(1)H) time scales at elevated temperature. Both base were required to convert amorphous "CdLClO4" precipitated in absence air complex. shares structural features with ζ-carbonic anhydrase...
Depending on the base used for induction of aldol cascade reaction either natural or non-natural steroid skeleton are selectively accessed.
Abstract The first example of a chiral‐catalyst‐controlled regioselective acetalization C2/C3‐OH carbohydrates such as (I) and (VIII) is described.