Facile Synthesis of N (alpha) -Protected Amino/Peptide Hydroxamic Acids Mediated by COMU

One-pot preparation of N (alpha) -protected amino/peptide hydroxamic acids from corresponding carboxylic acids is described using uronium-type coupling reagent COMU. The present protocol is simple and mild conditions are used. Thus the resulting hydroxamic acids are obtained in good yields without racemization

T3P® (propylphosphonic anhydride) Mediated Conversion of Carboxylic Acids into Acid Azides and one-pot Synthesis of Ureidopeptides

A general, mild, efficient, and environmentally benign protocol, which makes use of T3P® as an acid activating agent for the direct synthesis of acid azides from carboxylic acids is described. Further, the protocol is employed for the one-pot synthesis of α-ureidopeptides starting from N-protected α-amino acids

Synthesis of N-Fmoc-ProtectedAmino Alkyl Thiocyanates/Selenocyanates and their Applicationin the Preparation of 5-Substituted S/Se-Linked Tetrazoles

A novel class of N-Fmoc-protected amino alkyl thiocy- anates/selenocyanates has been prepared by thiocyanation/seleno-cyanation of the corresponding alkyl iodides. These thiocyanates/selenocyanates undergo a facile [2+3]-cycloaddition reaction with sodium azide to afford novel N-Fmoc amino alkylS/Se-linked tetra-zoles

An Efficient and Epimerization Free Synthesis of C-Terminal Arylamides Derived from α-Amino Acids and Peptide Acids via T3p Activation

A high yield and rapid synthesis of enantiomerically pure N α -protected amino/peptide acid arylamides using n-propylphosphonic anhydride (T3P) in presence of N-methylmorpholine is described. The generality of the reaction has been studied for various N α -protected amino acids with diverse range of aromatic amines and coumarin derivatives

One-Pot Synthesis of Weinreb Amides Employing 3,3-Dichloro-1,2-Diphenylcyclopropene (CPI-Cl) as a Chlorinating Agent

The synthesis of Na -protected amino alkyl Weinreb amides starting from the corresponding a-amino acids as well as carboxylic acids has been delineated through the in situ generation of acid chlorides using CPI-Cl as a chlorinating agent. The protocol is simple; the reaction conditions employed were mild, and compatible with all the three commonly used urethane protecting groups namely, Boc, Cbz and Fmoc groups. The resulting Weinreb amides are obtained in good yields as optically pure products

Montmorillonite K-10 supported palladium nanoparticles: A catalyst for the preparation of α-aminoynones employing copper free acyl Sonogashira reaction

977-982Palladium nanoparticles supported by Montmorillonite K-10 (MMT K-10) are utilized for the synthesis of α-amino ynones using amino acid chlorides and a mild base at room temperature. All the compounds were obtained in good yields. Furthermore, the catalyst is also utilized for the deprotection of protecting groups operating in peptide chemistry

Peptide Bond Formation via Nα-Protected Diacyldiselenides

Abstract A simple, straightforward, for the peptide bond formation employing corresponding carboxylic acids and amines derived from amino acids via Nα -protected diacyldiselenide is delineated. The key step of the synthesis is the in situ generation of Nα -protected diacyldiselenide using NaBH2Se3 as selenating reagent, followed by trapping with an amino acid ester leading to the peptide. The formation of Nα -protected diacyldiselenide was confirmed through TLC and HRMS analysis using crude sample. The reaction is clean and all the products were obtained in moderate to good yields, including for sterically hindered amino acids. The protocol is free from racemisation, compatible with Fmoc, Cbz and Boc groups