Conjugate Addition-Enantioselective Protonation of N-Aryl Glycines to α-Branched 2-Vinylazaarenes via Cooperative Photoredox and Asymmetric Catalysis.

An enantioselective protonation strategy has been successfully applied to the synthesis of chiral α-tertiary azaarenes. With a dual catalytic system involving a chiral phosphoric acid and a dicyanopyrazine-derived chromophore (DPZ) photosensitizer that is mediated by visible light, a variety of α-branched 2-vinylpyridines and 2-vinylquinolines with N-aryl glycines underwent a redox-neutral, radical conjugate addition-protonation process and provided valuable chiral 3-(2-pyridine/quinoline)-3-substituted amines in high yields with good to excellent enantioselectivities (up to >99% ee). An application of this methodology to a two-step synthesis of the enantiomerically pure medicinal compound pheniramine (Avil) is also presented.

Catalytic Asymmetric Conjugate Addition and Sulfenylation of Diarylthiazolidin-2,4-diones.

This work reports the first application of diarylthiazolidin-2,4-diones as nucleophiles in asymmetric catalysis. By utilizing chiral amino acid-based (thio)urea-tertiary amines as the catalysts, we successively established asymmetric conjugate addition to nitroolefins and sulfenylation to N-(sulfanyl)-succinimides of diarylthiazolidin-2,4-diones. Two series of biologically important 5-aryl-5-substituted thiazolidin-2,4-diones were obtained with high enantio- and diastereoselectivities (up to >99% ee and >19:1 dr). The enantioenriched adducts were found to show satisfactory anticancer activities against three different cancer cell lines using the MTT assay. All of these successes depended on the development of a general and expedient synthetic strategy to provide diverse 5H-thiazolidin-2,4-diones.

[Own experience on acupuncture sensation].

To summarize professor SUN Xuequan's own experience on the acupuncture sensation. Professor SUN Xuequan puts forward his opinion through the sensation of acupuncture on himself, from the aspects of the expression, the material basis, the distinction and the clinical significance of acupuncture sensation, etc. Professor SUN thinks that the production and conduction direction of acupuncture sensation have their material basis and objectively exist, based on which, professor SUN puts forward the amount of acupuncture stimulation and the total amount of acupuncture stimulation. Professor SUN believes that the amount of acupuncture stimulation is the main basis for the individual reinforcing and reducing of acupuncture. The amount of acupuncture stimulation is related to the depth and intensity of acupuncture, the time of the needle retention, the number of needles, etc. The reinforcing and reducing of acupuncture are relative to the deficiency and excess of the disease, and they are the reaction of acupuncture for body. The tolerance degree of the individual to the stimulation of acupuncture is also the main factor affecting the reinforcing and reducing.

Organocatalytic Asymmetric Cascade Aerobic Oxidation and Semipinacol Rearrangement Reaction: A Visible Light-Induced Approach to Access Chiral 2,2-Disubstituted Indolin-3-ones.

An enantioselective cascade aerobic oxidation and semipinacol rearrangement reaction of 2-aryl-3-alkyl-substituted indoles via visible-light-driven cooperative organophotoredox and H-bonding catalysis is reported. The current method provides an expedient and sustainable approach to furnish a variety of valuable chiral 2-aryl-2-alkyl-substituted indolin-3-ones in 64-90 % yield with 58-94 % ee. Preliminary control experiments present important insights into the stereochemistry.