A silicon-assisted synthesis of (E)-β-haloenamides fromN-vinylamides

A Platform for the Synthesis of Oxidation Products of Bilirubin

Bilirubin is the principal product of heme catabolism. High concentrations of the pigment are neurotoxic, yet slightly elevated levels are beneficial. Being a potent antioxidant, oxidative transformations of bilirubin occur in vivo and lead to various oxidized fragments. The mechanisms of their formation, intrinsic biological activities, and potential roles in human pathophysiology are poorly understood. Degradation methods have been used to obtain samples of bilirubin oxidation products for research. Here, we report a complementary, fully synthetic method of preparation. Our strategy leverages repeating substitution patterns in the parent tetracyclic pigment. Functionalized ready-to-couple γ-lactone, γ-lactam, and pyrrole monocyclic building blocks were designed and efficiently synthesized. Subsequent modular combinations, supported by metal-catalyzed borylation and cross-coupling chemistries, translated into the concise assembly of the structurally diverse bilirubin oxidation products (BOXes, propentdyopents, and biopyrrins). The discovery of a new photoisomer of biopyrrin A named lumipyrrin is reported. Synthetic bilirubin oxidation products made available in sufficient purity and quantity will support future in vitro and in vivo investigations.

Visible Light Induced Synthesis of (Z)-β-iodoenamides from N-Vinyl Amides Mediated by Ion Pair Charge Transfer State

A facile and novel approach for high chemo- and stereoselective synthesis of (Z)-β-iodoenamides from N-vinyl amides has been developed based on a visible-light-induced ion pair charge transfer state derived from...

Silylative coupling of olefins with vinylsilanes in the synthesis of functionalized alkenes

Recent developments in the sequential synthetic strategies including ruthenium-catalyzed silylative coupling followed by desilylation, leading to π-conjugated organic derivatives are presented.