A5025729584- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Asymmetric Synthesis and Catalysis
- Synthetic Organic Chemistry Methods
- Plant biochemistry and biosynthesis
- Microbial Natural Products and Biosynthesis
- Asymmetric Hydrogenation and Catalysis
- Synthesis and Catalytic Reactions
- Coordination Chemistry and Organometallics
- Traditional and Medicinal Uses of Annonaceae
- Alkaloids: synthesis and pharmacology
- Chemical synthesis and alkaloids
- Cyclopropane Reaction Mechanisms
- Organic Chemistry Cycloaddition Reactions
- Catalytic Alkyne Reactions
- Catalytic C–H Functionalization Methods
- Natural product bioactivities and synthesis
- Cancer Treatment and Pharmacology
- Chemical Synthesis and Reactions
- Sulfur-Based Synthesis Techniques
- Organoboron and organosilicon chemistry
- Chemical Synthesis and Analysis
- Ubiquitin and proteasome pathways
- Cancer therapeutics and mechanisms
- Crystallography and molecular interactions
Institute of Chemistry, Academia Sinica
2015-2025
Academia Sinica
2014-2025
Clinique Claude-Bernard
2015
National Taiwan University
2014
Harvard University
2007-2009
National Yang Ming Chiao Tung University
1996-2006
The outbreak of COVID-19 caused by SARS-CoV-2 has resulted in more than 50 million confirmed cases and over 1 deaths worldwide as November 2020. Currently, there are no effective antivirals approved the Food Drug Administration to contain this pandemic except antiviral agent remdesivir. In addition, trimeric spike protein on viral surface is highly glycosylated almost 200,000 variants with mutations at 1,000 positions its 1,273 amino acid sequence were reported, posing a major challenge...
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTConversion of Torgov's Synthesis Estrone into a Highly Enantioselective and Efficient ProcessYeung, Rong-Jie Chein, E. J. CoreyView Author Information Department Chemistry Chemical Biology, Harvard University, Cambridge, Massachusetts 02138 Cite this: Am. Chem. Soc. 2007, 129, 34, 10346–10347Publication Date (Web):August 2, 2007Publication History Received11 June 2007Published online2 August inissue 1...
Immune checkpoint inhibitors (ICIs) targeting PD-L1 immunotherapy are state-of-the-art treatments for advanced non-small cell lung cancer (NSCLC). However, the treatment response of certain patients with NSCLC is unsatisfactory because an unfavorable tumor microenvironment (TME) and poor permeability antibody-based ICIs. In this study, we aimed to discover small-molecule drugs that can modulate TME enhance ICI efficacy in vitro vivo. We identified a protein-modulating small molecule, PIK-93,...
Using a simple method, the aldehyde groups of zeolitic imidazolate framework-90 (ZIF-90) nanocrystals were converted into carboxyl, amino, and thiol groups, without affecting integrity framework. Notably, for first time, correlations between functionality cytotoxicity are also demonstrated via in vitro assays. The positive charged aminated-ZIF-90 presumably results either perturbation cell membrane, more efficient uptake, or both. Therefore, half-maximal effective (EC50 ) concentration has...
We report the asymmetric total synthesis of optically active nervione in both (+) and (−) forms, a natural product initially isolated from Nervilia concolor 2022. Beginning with commercially available resorcinol, pure was synthesized 10 steps, employing combination ortho-directed strategies crucial late-stage, Lewis acid-mediated, highly diastereoselective reduction. Discrepancies observed circular dichroism (CD) spectra prompted reassignment nervione's absolute configuration (3S, 8R) to (3R, 8S).
The first enantioselective total synthesis of (+)-(R)-concentricolide, the enantiomer an anti-HIV-1 agent isolated from Daldinia concentrica, 2-iodophenol in 7 steps reveals (S)-configuration for natural form furanophthalide. key features include anionic ortho-Fries rearrangement to furnish 3-iodosalicylamide, facile construction benzofuran system employing tandem Sonogashira coupling annulation reaction, directed ortho metalation introduce a propanoyl group, as well CBS reduction,...
This work describes an expeditious and efficient preparation of enantiopure (thiolan-2-yl)diphenylmethanol (2) featuring a double nucleophilic substitution Shi epoxidation as key steps. One the applications its benzyl ether derivative to asymmetric sulfur ylide-mediated with up 92% ee (14 examples) was also demonstrated herein.
Abstract The 1,3‐enyne moiety is commonly found in cyclohexanoid natural products produced by endophytic and plant pathogenic fungi. Asperpentyn ( 1 ) a 1,3‐enyne‐containing terpenoid isolated from Aspergillus Pestalotiopsis . genetic basis biochemical mechanism of biosynthesis , other containing this motif, has remained enigmatic despite their potential ecological roles. Identified here the biosynthetic gene cluster characterization two crucial enzymes A P450 monooxygenase that dual...
ADVERTISEMENT RETURN TO ISSUEPREVLetterNEXTStrong Conformational Preferences of Heteroaromatic Ethers and Electron Pair RepulsionRong-Jie Chein† E. J. Corey*‡View Author Information Department Chemistry Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, Institute Chemistry, Academia Sinica, 115 Nankang, Taipei, Taiwan[email protected]†Academia Sinica.‡Harvard University.Cite this: Org. Lett. 2010, 12, 1, 132–135Publication Date (Web):December 3, 2009Publication History...
This work describes catalytic and asymmetric aziridinations (15 examples, 95-98% ee) of benzyl bromide imines via the imino Corey-Chaykovsky reaction using (thiolan-2-yl)diarylmethanol ether as an organocatalyst. The catalyst analogues thereof were prepared through expeditious efficient synthetic route featuring a double nucleophilic substitution Shi epoxidation key steps.
2,3-(S)-Oxidosqualene (C30H50O) serves as a versatile starting point for the remarkable biosynthesis of many isomeric naturally occurring triterpenoids formula C30H50O. These biosyntheses all involve polycyclization via cationic intermediates. The fully cyclized primary products then are converted to various structures by rearrangements involving polycyclic backbone. energetics these has been examined B3LYP 6−31 G* DFT calculations and ab initio Hartree−Fock at 6−31G* or 3−21G(*) level....
(-)-Antrocin (1), produced by the medicinal mushroom Antrodia cinnamomea, is a potent antiproliferative compound. The biosynthetic gene cluster of 1 was identified, and pathway characterized heterologous expression. We haloacid dehalogenase-like terpene cyclase AncC that biosynthesizes drimane-type sesquiterpene (+)-albicanol (2) from farnesyl pyrophosphate (FPP). Biochemical characterization AncC, including kinetic studies mutagenesis, demonstrated functions two domains: (TC)...
A hydroxy-directed alkylation of an N,N-diethylarylamide using CIPE-assisted α-silyl carbanions (CIPE = complex-induced proximity effect) has been developed a simple reagent combination LDA (lithium diisopropylamide) and chlorosilane. study the mechanism, application procedure to anionic Snieckus-Fries rearrangement for highly efficient synthesis potent phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, are reported.
A highly efficient one-pot procedure was developed for the synthesis of various 2′-hydroxychalcones from phenyl diethylcarbamate, featuring consecutive Snieckus–Fries rearrangement, anionic Si → C alkyl and Claisen–Schmidt condensation in a single operation. The applicability this protocol demonstrated by anti-inflammatory natural product lonchocarpin. mechanism insight is also provided.
A mild and efficient combined-acid system using a zinc(ii) salt [ZnI2 or Zn(OTf)2] p-toluene sulfonic acid (TsOH) was investigated for catalytic cationic cyclizations, including intramolecular hydrocarboxylation, hydroalkoxylation, hydroamination, hydroamidation, hydroarylation polyene cyclizations. This reaction provides easy access to five- six-membered O- N-containing saturated heterocyclic compounds, tetrahydronaphthalene derivatives polycyclic skeletons in excellent yield with perfect...
Drug resistance has been a major threat in cancer therapies that necessitates the development of new strategies to overcome this problem. We report here cell-based high-throughput screen library containing two-million molecules for compounds inhibit proliferation non-small-cell lung (NSCLC). Through process phenotypic screening, target deconvolution, and structure–activity relationship (SAR) analysis, compound furanonaphthoquinone-based small molecule, AS4583, was identified exhibited potent...
We report a new class of chiral tetrahydroselenophene based on (S)-diphenyl(tetrahydroselenophen-2-yl)methanol, which was prepared from (R)-3-(3-bromopropyl)-2,2-diphenyloxirane and sodium selenide. These tetrahydroselenophene-based compounds were used to catalyze asymmetric cyclopropanation reactions; the selenonium ylide intermediates formed these selenium-containing catalysts benzyl bromide efficiently react with (E)-chalcones give various cyclopropanes (27 examples) excellent...
The oxazaborolidine-catalyzed reduction of 2,2-disubstituted cycloalkan-1,3-diones or hindered cyclic ketones using catecholborane as reductant proceeds with greater enantioselectivity when N,N-diethylaniline is added. It has now been shown that the effect this additive to catalyze conversion a harmful minor impurity in catalyst preparations active catalyst.
The first chemical synthesis of galanal A and B was achieved by a concise highly efficient pathway starting from commercially available (+)-sclareolide features Wittig reaction titanocene-mediated radical cyclization as the key steps.
The first reported sulfur-stabilized borenium cations were synthesized through halide abstraction of a haloborane intermediate by halophilic reagents. Different from the well-known cationic oxazaborolidines, sulfide instead an amine was used to not only simplify preparation catalysts but also increase Lewis acidity boron atom. in situ generated salts showed exceptional and successfully catalyzed asymmetric Diels–Alder reactions cyclopentadiene dienophiles excellent yields...
The first total synthesis of galanal A and B has been achieved from naturally occurring geraniol. Key steps in this are the use a Lewis acid assisted chiral Brønsted (chiral LBA) mediated cationic polyene cyclization titanocene-mediated radical for asymmetric assembly "AB" ring construction all-carbon quaternary center at junction "BC" ring, respectively.
(-)-Aurantioclavine (1), which contains a characteristic seven-membered ring fused to an indole ring, belongs the azepinoindole class of fungal clavine alkaloids. Here we show that starting from 4-dimethylallyl-l-tryptophan precursor, flavin adenine dinucleotide (FAD)-binding oxidase and catalase-like heme-containing protein are involved in biosynthesis 1. The function these two enzymes was characterized by heterologous expression, vitro characterization, deuterium labeling experiments.
2-Isocyanoallopupukeanane (4) has been obtained in racemic form from methyl 2-exo-methylbicyclo[2.2.1]hept-5-ene-2-endo-carboxylate via dibromocarbene addition, S(N)2' displacement, chain extension, and elaboration of the unsaturated ketone 12c which underwent an intramolecular hetero-Diels-Alder reaction to afford 13 containing all skeletal carbon atoms. The dihydropyran unit was cleaved by ozonolysis give tricarbocyclic intermediate required seven more steps complete synthesis.