A5072244450- Chemical Synthesis and Analysis
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- biodegradable polymer synthesis and properties
- Advanced Polymer Synthesis and Characterization
- Radical Photochemical Reactions
- Crystallography and molecular interactions
- Protein Structure and Dynamics
- Biopolymer Synthesis and Applications
- Synthesis and Biological Evaluation
- Catalytic C–H Functionalization Methods
- Enzyme Structure and Function
- Nanoparticle-Based Drug Delivery
- Crystallization and Solubility Studies
- Advanced Proteomics Techniques and Applications
- Sulfur-Based Synthesis Techniques
- Catalytic Cross-Coupling Reactions
- Glycosylation and Glycoproteins Research
- Covalent Organic Framework Applications
- Nanoplatforms for cancer theranostics
- NMR spectroscopy and applications
- Lanthanide and Transition Metal Complexes
- Dendrimers and Hyperbranched Polymers
- Supramolecular Self-Assembly in Materials
- Polymer Surface Interaction Studies
Zhejiang University
2020-2023
Zhejiang University of Technology
2019-2022
Hangzhou Xixi hospital
2019-2020
Purdue University West Lafayette
2014-2017
University at Albany, State University of New York
1993
Albany State University
1993
Abstract An efficient visible‐light‐induced (thio)etherification of quinoxalin‐2(1H)‐ones with divergent aliphatic alcohols and thiols (primary, secondary, tertiary) at room temperature in air has been developed. This protocol was highlighted by its mild conditions, readily available starting materials, operational simplicity, wide functional group tolerance. magnified image
A practical and scalable protocol for electrochemical arylation of quinoxalin(on)es with arylhydrazine hydrochlorides under mild conditions has been developed. This method exhibits high efficiency, easy scalability, broad functional group tolerance. Various arylhydrazines underwent this transformation smoothly in an undivided cell, providing the corresponding aryl-substituted moderate to good yields. radical mechanism is involved reaction.
The copper-catalyzed versatile C(sp2)–C(sp3) bond formation with N-heteroaromatics and hydrogen donors was developed. Various alkanes ethers reacted quinolines, isoquinolins, pyridines, benzooxazole benzothiazole to give the corresponding C(sp2)–H alkylation products via cross-dehydrogenative coupling. On other hand, we achieved high regioselective C(sp2)–halogen of (hetero)aryl chlorides bromides elimination halogen radical. reaction mechanism investigated control experiments.
Polysarcosine (PSar), a water-soluble polypeptoid, is gifted with biodegradability via the random ring-opening copolymerization of sarcosine- and alanine-N-thiocarboxyanhydrides catalyzed by acetic acid in controlled manners. Kinetic investigation reveals behavior two monomers. The copolymers, named PaS, high molecular weights between 5.3 43.6 kg/mol tunable Ala molar fractions varying from 6 to 43% can be degraded porcine pancreatic elastase within 50 days under mild conditions (pH = 8.0 at...
The acyl substitution reactions between 1-hydroxy-7-aza-benzotriazole (HOAt)/1-hydroxy-benzotriazole (HOBt) ester reagents and nucleophilic side chains on peptides have been demonstrated in the gas phase via ion/ion reactions. HOAt/HOBt were synthesized solution ionized negative nano-electrospray ionization. anionic then reacted with doubly protonated model containing amines, guanidines, imidazoles phase. complexes formed reaction cell further probed ion trap collision induced dissociation...
Glycine-rich proteins (GRPs) containing a high content of glycine residues (>30%) possess unique structural stability. However, the controllable synthesis glycine-rich poly(amino acid)s (PAAs) to mimic GRPs has not been realized yet due poor solubility polyglycine segments. We developed novel method synthesize PAAs via controlled ring-opening copolymerization glycine-N-thiocarboxyanhydrides (Gly-NTA) with sarcosine-N-carboxyanhydride and ε-Cbz-l-lysine-N-carboxyanhydride. The random is...
Main observation and conclusion Block copolymers not only combine properties of different segments but also generate new application prospects. Poly(α‐amino acid)‐ b ‐poly(tetrahydrofuran)‐ ‐poly(α‐amino acid) (PAA‐PTHF‐PAA) is one the copolymers. In this contribution, di‐hydroxyl‐ended HO‐PTHF‐OH transferred into di‐oxyamino‐ended H 2 NO‐PTHF‐ONH quantitatively, which used as a macroinitiator to polymerize sarcosine N ‐thiocarboxyanhydride (Sar‐NTA) ‐phenyoxycarbonyl ‐ε‐carbobenzyloxy‐ D...
N-hydroxysuccinimide (NHS) esters have been used for gas-phase conjugation reactions with peptides at nucleophilic sites, such as primary amines (N-terminus, ε-amine of lysine) or guanidines, by forming amide bonds through a attack on the carbonyl carbon. The carboxylate has recently found to also be reactive nucleophile capable initiating similar form labile anhydride bond. fragile bond is easily cleaved, resulting in an oxygen transfer from carboxylate-containing species reagent, nominally...
The fragmentation of peptides and proteins upon collision-induced dissociation (CID) is highly dependent on sequence ion type (e.g. protonated, deprotonated, sodiated, odd electron, etc.). Some amino acids, for example aspartic acid proline, have been found to enhance certain cleavages along the backbone. Here, we show that containing dehydroalanine, a non-proteinogenic with an unsaturated side-chain, undergo enhanced cleavage N—Cα bond dehydroalanine residue generate c- z-ions. Because...
Fluorescence imaging (FLI) in the near-infrared-II (NIR-II; 1000-1700 nm) window holds great potential for cancer metastasis owing to its deep tissue penetration and a high signal-to-background ratio. However, currently reported organic NIR-II contrast agents generally present problems such as poor water solubility, low fluorescence quantum yield (QY), short blood circulation half-life (t1/2), injection doses, undesirable tumor accumulation. In this study, an small-molecule-based polymer...
We examine a gas-phase approach for converting subset of amino acid residues in polypeptide cations to dehydroalanine (Dha). Subsequent activation the modified ions gives rise specific cleavage N-terminal Dha residue. This process allows incorporation selective cleavages structural characterization ions. An ion/ion reaction within mass spectrometer between multiply protonated and sulfate radical anion introduces site into reactant. collisional cation side chain loss from one several...
This review summarizes recent literature describing the use of gas phase radical reactions for structural characterization complex biomolecules other than peptides. Specifically, chemical derivatization, in-source reaction, and ion/ion have been demonstrated as effective ways to generate precursor ions that yield informative fragments complementary those from conventional collision-induced dissociation (CID). Radical driven has applied a variety including peptides, nucleic acids,...
Gas-phase amidation of carboxylic acids in multiply-charged peptides is demonstrated via ion/ion reactions with Woodward's reagent K (wrk) both positive and negative mode. K, N-ethyl-3-phenylisoxazolium-3'-sulfonate, a commonly used that activates carboxylates to form amide bonds amines solution. Here, we demonstrate the analogous gas-phase chemistry occurs upon reaction wrk ions doubly protonated (or deprotonated) peptide containing acid functionality. The involves formation enol ester...
SANS experiments by interpenetrating networks of poly(carbonate-urethane) and polyvinyl pyridine reveal that there is some degree microphase separation at all compositions, possibly, in into a bicontinuous phase. The domain size undred angstroms the samples with only one glass transition temperature, much smaller than for two temperatures
Our work demonstrates the detailed mechanism to synthesize NCA and NTA monomers racemization process of optical pure monomers.
Nature creates sophisticated proteins via programming amino acid monomers. In contrast, the chemical approach toward both long and sequence-controlled polypeptides still remains a challenge. Inspired by Nature, we develop novel topochemical reaction named "interlocked polymerization in cocrystals" (iPiC) chiral-sequence controlled with DL-alternating order. By crystallization, racemic methionine N-thiocarboxyanhydride (rac-Met-NTA) is programmed as D/L pairs located "sandwich" structure...
Polysarcosine (PSar), a water-soluble polypeptoid, is gifted with biodegradability via random ring-opening copolymerization of sarcosine- and alanine-N-thiocarboxyanhydrides catalyzed by acetic acid in controlled manners. Kinetic investigation reveals the behavior two monomers. The copolymers, named PAS, high molecular weights between 22.0 43.6 kg/mol tunable Ala molar fractions varying from 6% to 43% are able be degraded porcine pancreatic elastase within 50 days mild conditions (pH=8.0 at...
Polysarcosine (PSar), a water-soluble polypeptoid, is gifted with biodegradability via random ring-opening copolymerization of sarcosine- and alanine-N-thiocarboxyanhydrides catalyzed by acetic acid in controlled manners. Kinetic investigation reveals the behavior two monomers. The copolymers, named PAS, high molecular weights between 22.0 43.6 kg/mol tunable Ala molar fractions varying from 6% to 43% are able be degraded porcine pancreatic elastase within 50 days mild conditions (pH=8.0 at...