[C+NC+CC] Coupling-Enabled Synthesis of Influenza Neuramidase Inhibitor A-315675

Amino Acid and Peptide-Based Antiviral Agents

A significant number of antiviral agents used in clinical practice are amino acids, short peptides, or peptidomimetics. Among them, several HIV protease inhibitors (e. g. lopinavir, atazanavir), HCV protease inhibitors (e. g. grazoprevir, glecaprevir), and HCV NS5A protein inhibitors have contributed to a significant decrease in mortality from AIDS and hepatitis. However, there is an ongoing need for the discovery of new antiviral agents and the development of existing drugs; amino acids, both proteinogenic and non-proteinogenic in nature, serve as convenient building blocks for this purpose. The synthesis of non-proteinogenic amino acid components of antiviral agents could be challenging due to the need for enantiomerically or diastereomerically pure products. Herein, we present a concise review of antiviral agents whose structures are based on amino acids of both natural and unnatural origin. Special attention is paid to the synthetic aspects of non-proteinogenic amino acid components of those agents.

Asymmetric formal synthesis of (−)-tetrazomine

The asymmetric formal synthesis of (−)-tetrazomine, a structurally unique member of the tetrahydroisoquinoline alkaloids, is presented.

Cycloaddition/annulation strategies for the construction of multisubstituted pyrrolidines and their applications in natural product synthesis

Pyrrolidines are privileged substructures of numerous bioactive natural products and drugs.

Catalytic asymmetric exo-selective [C+NC+CC] reaction

A catalytic asymmetric version of the exo-selective [C+NC+CC] reaction is reported. This multicomponent reaction utilizes a readily prepared achiral glycyl sultam as the "NC" component and commercially available catalyst components. The method can be applied to a variety of aldehydes ("C" component) and activated alkenes ("CC" component) to provide substituted pyrrolidines in good yields and high enantioselectivities. Of particular note is the ability to employ labile enolizable aldehydes (e.g., acetaldehyde and propionaldehyde) in this reaction.

Recent advances in the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides

The scope of the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides has been greatly expanded by the incorporation of novel types of dipolarophiles and dipole precursors. This feature article summarizes the recent development in this area.