Easily accessible chiral dicyclopentadiene ligands for rhodium-catalyzed enantioselective 1,4-addition reactions

A variety of novel C₁-symmetric chiral diene ligands based on the dicyclopentadiene (DCP) skeleton were easily prepared from commercially available DCP. The application of these diene ligands in the rhodium-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds has been examined and excellent enantioselectivities (up to 97% ee) as well as good yields were achieved under mild reaction conditions.     

Eosin Y as a Direct Hydrogen‐Atom Transfer Photocatalyst for the Functionalization of C−H Bonds

Eosin Y, a well‐known economical alternative to metal catalysts in visible‐light‐driven single‐electron transfer‐based organic transformations, can behave as an effective direct hydrogen‐atom transfer catalyst for C?H activation. Using the alkylation of C?H bonds with electron‐deficient alkenes as a model study revealed an extremely broad substrate scope, enabling easy access to a variety of important synthons. This eosin Y‐based photocatalytic hydrogen‐atom transfer strategy is promising for diverse functionalization of a wide range of native C?H bonds in a green and sustainable manner.     

Modular One‐Step Three‐Component Synthesis of Tetrahydroisoquinolines Using a Catellani Strategy

Reported is a modular one‐step three‐component synthesis of tetrahydroisoquinolines using a Catellani strategy. This process exploits aziridines as the alkylating reagents, through palladium/norbornene cooperative catalysis, to enable a Catellani/Heck/aza‐Michael addition cascade. This mild, chemoselective, and scalable protocol has broad substrate scope (43 examples, up to 90 % yield). The most striking feature of this protocol is the excellent regioselectivity and diastereoselectivity observed for 2‐alkyl‐ and 2‐aryl‐substituted aziridines to access 1,3‐cis‐substituted and 1,4‐cis‐substituted tetrahydroisoquinolines, respectively. Moreover, this is a versatile process with high step and atom economy.     

An “<Emphasis Type="Italic">In Vivo</Emphasis> Self-assembly” Strategy for Constructing Superstructures for Biomedical Applications

The interfacing study of biopolymer and supramolecular chemistry enables a better understanding of fundamental biochemical processes and the creating of new high-performance biomaterials. In this review, we introduced an “in vivo self-assembly” strategy which means in situ construction of functional self-assembled superstructures in specific physiological or pathological conditions in cell, tissue or animal levels that exhibit diverse biomedical effects. By using this strategy, unexpected phenomena and insights, e.g, assembly/aggregation induced retention (AIR) effect have been demonstrated where the self-assembled nanostructures showed extraordinary enhanced accumulation and retention of therapeutics in targeted sites.     

On-line coupling of capillary isoelectric focusing with transient isotachophoresis-zone electrophoresis: a two-dimensional separation system for proteomics

A microdialysis junction is employed as the interface for on-line coupling of capillary isoelectric focusing with transient isotachophoresis-zone electrophoresis in a two-dimensional separation system. Capillary isoelectric focusing not only provides high-resolution separation of tryptic peptides based on their differences in isoelectric point, but also potentially allows the analysis of low-abundance proteins with a typical concentration factor of 50-100 times. Carrier ampholytes, employed for the creation of a pH gradient during focusing, are further utilized as the leading electrolyte in the second separation dimension, transient isotachophoresis-zone electrophoresis. Many peptides which have the same isoelectric point would most likely have different charge-to-mass ratios, and thus different electrophoretic mobilities in zone electrophoresis. Two-dimensional separation of proteolytic peptides is demonstrated using standard proteins, including cytochrome c, ribonuclease A, and carbonic anhydrase II. The maximum peak capacity is estimated to be around approximately 1600 and can be significantly increased by simply increasing the capillary column length and manipulating the range of pH gradient in isoelectric focusing. In addition to enhanced separation efficiency and resolution, this two-dimensional electrokinetic separation system permits sensitive and comprehensive analysis of peptide fragments, especially when integrated with electrospray ionization mass spectrometry for peptide/protein identification.     

甲磺酸多沙唑嗪的合成

甲磺酸多沙唑嗪(doxazosin mesylate,Ⅰ)的化学名为1-(4-氨基-6,7-二甲氧基-2-喹唑啉基)-4-(1,4-苯骈二恶烷-2-甲酰基)哌嗪甲磺酸盐,是一种新型的高选择性α1受体阻滞剂[1],半衰期长,且有明显的降压和降脂作用,同时对单纯性前列腺增生引起的排尿困难具有良好的作用.目前已成为国内外治疗轻中度高血压的一线药物[2,3,4].     

聚β-羟基丁酸酯接枝顺丁烯二酸酐的研究

接枝共聚反应;聚β-羟基丁酸酯接枝顺丁烯二酸酐的研究