Phenyl Selenoesters Research Articles

Polyfluorophenyl Ester-Terminated Homobifunctional Cross-Linkers for Protein Conjugation

Along with N-hydroxysuccinimidyl, p-nitrophenyl, and phenylseleno esters, tetra- and penta-fluorophenyl esters were comparatively evaluated in term of their reactivity and hydrolytic stability. Their homobifunctional cross-linkers were prepared to conjugate proteins with small molecules, including carbohydrates, fluorescent dyes, and poly(ethylene glycol) monomethyl ether. The conjugations proceeded under mild conditions, affording the corresponding protein conjugates with good efficiency.

General, Mild, and Metal-Free Synthesis of Phenyl Selenoesters from Anhydrides and Their Use in Peptide Synthesis.

A mild, practical, and simple procedure for phenyl selenoesters synthesis from several anhydrides and diphenyl diselenide was developed. This transition-metal-free method provides a straightforward entry to storable Fmoc-amino acid selenoesters which are effective chemoselective acylating reagents. An application to oligopeptide synthesis was illustrated.

One-Pot Ligation-Oxidative Deselenization at Selenocysteine and Selenocystine.

The use of native chemical ligation at selenocysteine (Sec) residues with peptide thioesters and additive-free selenocystine ligation with peptides bearing phenyl selenoesters, in concert with one-pot oxidative deselenization chemistry, is described. These approaches provide a simple and rapid method for accessing native peptides with serine in place of Sec at the ligation junction. The efficiency of both variants of the one-pot ligation-oxidative deselenization chemistry is probed through the synthesis of a MUC5AC-derived glycopeptide.

ChemInform Abstract: Acyl Radicals: Intermolecular and Intramolecular Alkene Addition Reactions.

A full study of the use of phenyl selenoesters as precursors to acyl radicals and their subsequent participation in intermolecular and intramolecular alkene addition reactions is detailed. Primary alkyl-, vinyl-, and aryl- substituted acyl radicals generated by Bu 3 SnH treatment of the corresponding phenyl selenoesters participate cleanly un intermolecular addition reactions with alkenes bearing electron-withdrawing or radical-stabilizing substituents at rates that exceed those of the potentially competitive decarbonylation or reduction

ChemInform Abstract: An Acyl Radical Initiated Tandem 7-endo/5-exo-Radical Cyclization Approach to Enantiomerically Pure Bicyclo(5.3.0)decan-2-ones.

Abstract The preparation of acetonide derivatives of erythro and threo 4,5-dihydroxyhept-6-enoic acids from the chiral pool is described. The phenylseleno esters derived from these acids undergo cyclization with tributyltin hydride to give mixtures of cyclohexanones and cycloheptanones. The inclusion of the appropriate four carbon side chain at C-7 leads, via a tandem radical cyclization process, to the title compounds in moderate yield.

Intramolecular reactions of 2-indolylacyl radicals: access to 1,2-fused ring indole derivatives.

The generation of 2-indolylacyl radicals from the corresponding phenyl selenoesters under reductive conditions and their behavior in intramolecular addition reactions to carbon-carbon double bonds located at the indole nitrogen have been studied. [reaction: see text]

Generation and Intermolecular Reactions of 3‐Indolylacyl Radicals.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Generation and intermolecular reactions of 3-indolylacyl radicals.

The generation of 3-indolylacyl radicals from the corresponding phenyl selenoesters and the scope of their participation in intermolecular addition reactions to carbon-carbon double bonds under both reductive and nonreductive conditions have been studied.

Generation and intermolecular reactions of 2-indolylacyl radicals.

The generation of 2-indolylacyl radicals from the corresponding phenyl selenoesters, aldehydes, and alpha-keto carboxylic acids and the scope of their participation in intermolecular addition reactions to carbon-carbon double bonds have been studied. Whereas the phenyl selenoester method has provided easy access to a variety of 1,4-dicarbonyl compounds bearing the 2-acylindole moiety, the glyoxylic acid route has been employed for the preparation of 2-indolyl pyridyl ketones.

A New Radical Route to C4-Unsubstituted β-Lactams

C4-Unsubstituted β-lactams 3 are conveniently prepared from easily available 4-formyl-β-lactams 1, in a sequential three step synthesis, using as the key step a radical reductive decarbonylation of 4-carboxy derivatives through their phenyl selenoesters 2. © 1997 Elsevier Science Ltd. All rights reserved.

Acyl radicals: intermolecular and intramolecular alkene addition reactions

A full study of the use of phenyl selenoesters as precursors to acyl radicals and their subsequent participation in intermolecular and intramolecular alkene addition reactions is detailed. Primary alkyl-, vinyl-, and aryl- substituted acyl radicals generated by Bu 3 SnH treatment of the corresponding phenyl selenoesters participate cleanly un intermolecular addition reactions with alkenes bearing electron-withdrawing or radical-stabilizing substituents at rates that exceed those of the potentially competitive decarbonylation or reduction

ChemInform Abstract: Tandem Free-Radical Alkene Addition Reactions of Acyl Radicals.

Acyl radicals generated from phenyl selenoesters serve as productive functionalized free radicals useful in the initiation of a) intramolecular polycyclizations - see the example (I) → (IIIa + b), b) tandem intramolecular cyclization-intermolecular addition reactions - see the example (V) + (VI) → (VII) + (VIII), and c) tandem intermolecular addition-intramolecular cyclization reactions - see the examples (IX) + (X) → (XI) + (XII) or (XIII) + (VIa) → (XIV) + (XV).

ChemInform Abstract: Phenyl Selenoesters as Effective Precursors of Acyl Radicals for Use in Intermolecular Alkene Addition Reactions.

ChemInform Abstract: Phenyl Selenoesters as Effective Precursors of Acyl Radicals for Use in Intermolecular Alkene Addition Reactions.

Phenyl selenoesters as effective precursors of acyl radicals for use in intermolecular alkene addition reactions

Phenyl selenoesters as effective precursors of acyl radicals for use in intermolecular alkene addition reactions

ChemInform Abstract: Acyl Radicals: Functionalized Free Radicals for Intramolecuar Cyclization Reactions.

AbstractThe phenyl selenoesters (I), (III), (V), and (VII) undergo intramolecular free‐radical cyclization upon treatment with tri‐n‐butyltin hydride/AIBN to form the cyclic proucts (II), (IV), (VI), or (VIII) via acyl radical intermediates.