Bifunctional Chiral Electrocatalysts Enable Enantioselective α-Alkylation of Aldehydes.

Herein, we describe an innovative approach to the asymmetric electrochemical α-alkylation of aldehydes facilitated by a newly designed bifunctional chiral electrocatalyst. The highly efficient bifunctional chiral electrocatalyst combines a chiral aminocatalyst with a redox mediator. It plays a dual role as a redox mediator for electrooxidation, while simultaneously providing remarkable asymmetric induction for the stereoselective α-alkylation of aldehydes.

Green process innovation, green product innovation, leverage, and corporate financial performance; evidence from system GMM.

Natural resource usage has produced various environmental challenges. Green process innovation has been considered a viable option that can help both industry and society. This study investigates the impact of green process innovation and green product innovation on corporate financial performance.

Effects of microcystin on protein profile in hepatopancreas of .

For intensive aquaculture in freshwater ponds, microcystin (MC-LR) generated from cyanobacterial blooms is one of the bottlenecks for the healthy and sustainable development of shrimp aquaculture industry. In this study, we measured the MC-LR content in the hepatopancreas and muscles of stressed by MC-LR, and analyzed protein expression in the hepatopancreas using DIA high-throughput proteomics technology. The results showed that MC-LR content in the hepatopancreas and muscles reached the highest at 1 h after MC-LR injection, which was (6.

Surgical treatment of massive stoma site tumors after a curative operation for rectal cancer.

Objective: This study aimed to evaluate the clinical and oncological outcomes of selected rectal cancer patients with massive stoma site tumors who underwent radical resection and reconstruction.

Methods: We reviewed 8 cases of massive stoma site tumors in patients who had permanent gastrointestinal stoma in the abdominal wall following radical resection of rectal cancer between March 2013 and May 2018 at the Peking University Cancer Hospital and Peking University Shougang Hospital.

Results: There were seven males and one female patient, with a median age of 50.

Case-matched study of short-term effects of 3D vs 2D laparoscopic radical resection of rectal cancer.

Background: The purpose of this study is to compare and evaluate the security and efficacy of 3D vs 2D laparoscopy in rectal cancer treatment.

Methods: Forty-six patients who suffered from rectal cancer and went on laparoscopic radical resection of rectal carcinoma in Peking University Shougang Hospital from Feb. 2015 to Mar.

Asymmetric organocatalytic direct aldol reactions of ketones with alpha-keto acids and their application to the synthesis of 2-hydroxy-gamma-butyrolactones.

A variety of organocatalysts for the asymmetric direct aldol reactions of ketones with alpha-keto acids were designed on the basis of molecular recognition and prepared from proline and aminopyridines. The organic molecule 8e, derived from proline and 6-methyl-2-amino pyridine, was the best catalyst, affording excellent enantioselectivities (up to 98% ee) for the direct aldol reactions of acetone or 2-butanone with a wide range of alpha-keto acids and for the reactions of various acyclic aliphatic ketones with 3-(2-nitrophenyl)-2-oxopropanoic acid. The aldol adducts could be converted to 2-hydroxy-gamma-butyrolactones by reaction sequences of diastereoselective reduction and lactonization.

Design of organocatalysts for asymmetric direct syn-aldol reactions.

Two new organocatalysts 3a and 3b, derived from L-leucine and (S)-beta-amino alcohols that were prepared from L-valine, were designed and afforded the direct syn-aldol reactions of a wide scope of aldehydes with various ketones with an excellent diastereomeric ratio of up to >20/1 and enantioselectivities of up to 99% ee.