Gabapentin hybrid peptides and bioconjugates

Visible-Light-Mediated Synthesis of Thioesters Using Thiocarboxylic Acid as the Dual Reagent

We have developed a visible-light-driven method for thioester synthesis that relies on the unique dual role of thiobenzoic acids as one-electron reducing agents and reactants leading to the formation of sulfur radical species. This synthetic process offers a wide scope, accommodating various thioacid and thiol substrates without the need for a photocatalyst.

Selective formation of γ-lactams via C-H amidation enabled by tailored iridium catalysts

Intramolecular insertion of metal nitrenes into carbon-hydrogen bonds to form γ-lactam rings has traditionally been hindered by competing isocyanate formation. We report the application of theory and mechanism studies to optimize a class of pentamethylcyclopentadienyl iridium(III) catalysts for suppression of this competing pathway. Modulation of the stereoelectronic properties of the auxiliary bidentate ligands to be more electron-donating was suggested by density functional theory calculations to lower the C-H insertion barrier favoring the desired reaction. These catalysts transform a wide range of 1,4,2-dioxazol-5-ones, carbonylnitrene precursors easily accessible from carboxylic acids, into the corresponding γ-lactams via sp³ and sp² C-H amidation with exceptional selectivity. The power of this method was further demonstrated by the successful late-stage functionalization of amino acid derivatives and other bioactive molecules.

Structural and morphological diversity of self-assembled synthetic γ-amino acid containing peptides

We report the synthesis of constrained amino acid building block gabapentin (Gpn) based hybrid peptides and their structural and morphological diversity in different conditions.