Acid-Promoted Phosphorylation of Ynones for the Synthesis of Phosphoryl Enones.

An efficient phospha-aldol/Meyer-Schuster rearrangement cascade reaction between propargylic aldehydes and phosphine oxides has been developed in which various phosphoryl enones were obtained in moderate to excellent yields. A comprehensive series of mechanistic experiments, including the identification of key intermediates and the application of O isotope labeling, has confirmed that this cascade reaction proceeds through a phospha-aldol followed by Meyer-Schuster rearrangement cascade reaction.

Copper-Catalyzed Domino Phosphorylation/Cyclization of -Alkynylketones for Accessing Phosphorylated 1-Isochromenes.

An effective and economical copper-catalyzed approach for the synthesis of phosphorylated 1-isochromenes is reported. This method is the first example of focus on ketone phosphonylation to establish a C-P bond and 6-- cyclization to construct a C-O bond between aryl- and alkyl-substituted alkynylketones and H-phosphinate esters, H-phosphites, and H-phosphine oxides, resulting in chemo- and regioselective phosphorylated 1-isochromenes with moderate to excellent yields under smooth reaction conditions.

Interrupted Michael Reaction: Sulfophosphinoylation of α,β-Unsaturated Ketones Catalyzed by Phosphine.

An efficient method for phosphine-catalyzed sulfophosphinoylation of α,β-unsaturated ketones for synthesis allylic organophosphorus compounds has been reported, in which α,β-unsaturated compounds acting as zwitterions react with electrophiles and nucleophiles to form a C-P bond and a C-O bond and obtain allylic organophosphorus with high regio- and stereoselectivity in moderate to excellent yields.

Acid-Promoted Multicomponent Reaction To Synthesize 4-Phosphorylated 4-Chromenes.

An effective multicomponent reaction for the synthesis of 4-phosphorylated 4-chromenes via a tandem phosphorylation/alkylation/cyclization/dehydration sequence with water as the only byproduct was developed. Extensive mechanistic investigations involving in situ NMR experiments, time control experiments, and in situ HRMS experiment allowed us to elucidate the order of each subreaction to arrive at a complete understanding of the underlying mechanism of this multicomponent reaction. Mechanistic data confirm that the reaction begins with a phospha-aldol-elimination, followed by addition of a ketone enolate, intermolecular alkylation, intramolecular cyclization, and dehydration under acidic conditions.

Lewis-acid-catalyzed phosphorylation of alcohols.

An efficient method has been developed for reacting dialkyl H-phosphonates or diarylphosphine oxides with alcohols for constructing C-P bonds. This reaction was catalyzed by Lewis acid and involved nucleophilic substitution. A series of diphenylphosphonates and diphenylphosphine oxides were obtained, from the phosphorylation of alcohols, with good-to-excellent yields.

Three-Component Direct Phosphorylation of Aldehydes and Alkylation of Ketones: Synthesis of γ-Ketophosphine Oxides under Acidic Conditions.

An effective and economical acid-promoted three-component reaction for the construction of C-P and C-C bonds for the synthesis of γ-ketophosphine oxides with water as the only byproduct was developed. Detailed mechanistic experiments confirmed that the reaction proceeds by phospha-aldol elimination, in which a benzylic carbocation is generated from the phosphorylation of aldehydes, which then reacts with ketone enolates under acidic conditions.

Reducing Virus Infection Risk in Space Environments through Nutrient Supplementation.

Space exploration has brought many challenges to human physiology. In order to evaluate and reduce possible pathological reactions triggered by space environments, we conducted bioinformatics analyses on the methylation data of the Mars 520 mission and human transcriptome data in the experiment simulating gravity changes. The results suggest that gene expression levels and DNA methylation levels were changed under the conditions of isolation and gravity changes, and multiple viral infection-related pathways were found in the enrichment analysis results of changed genes including Epstein Barr virus (EBV) infection, Hepatitis B virus (HBV) infection, Herpes simplex virus (HSV) infection and Kaposi's sarcoma-associated herpesvirus (KHSV) infection.