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Precisely controlling the product selectivity of a reaction is an important objective in organic synthesis. α‐Ketoamides are vital intermediates in chemical transformations and privileged motifs in numerous drugs, natural products, and biologically active molecules. The selective synthesis of α‐ketoamides from feedstock chemicals in a safe and operationally simple manner under mild conditions is a long‐standing catalysis challenge. Herein, an unprecedented TBD‐switched Pd‐catalyzed double isocyanide insertion reaction for assembling ketoamides in aqueous DMSO from (hetero)aryl halides and pseudohalides under mild conditions is reported. The effectiveness and utility of this protocol are demonstrated by its diverse substrate scope (93 examples), the ability to late‐stage modify pharmaceuticals, scalability to large‐scale synthesis, and the synthesis of pharmaceutically active molecules. Mechanistic studies indicate that TBD is a key ligand that modulates the Pd‐catalyzed double isocyanide insertion process, thereby selectively providing the desired α‐ketoamides in a unique manner. In addition, the imidoylpalladium(II) complex and α‐ketoimine amide are successfully isolated and determined by X‐ray analysis, confirming that they are probable intermediates in the catalytic pathway. [ABSTRACT FROM AUTHOR]

A convenient electrochemical oxidative cascade cyclization of alkenes equipped with pendant alcohols with general nucleophiles was developed. Using readily available diarylmethanimine and carboxylic acids as nucleophilic sources, a broad range of internal alkene and terminal alkene substrates could produce RCO 2 - and Ar 2 CN-functionalized O -heterocycles in moderate to high yields without the requirement for external oxidants and metals. These resulting products can subsequently be hydrolyzed to yield valuable NH 2 - and OH-functionalized tetrahydrofurans and tetrahydropyranes under mild conditions. Importantly, the efficient conversion of secondary alcohol products to amines with complete inversion of configuration enhances the methodology, enabling the construction of 2-aryl-3-amino tetrahydrofuran with high and complementary diastereoselectivity.

Toward a selective and facile method for the synthesis of CF 3 -containing pyrazolo[1,5- c ]quinazolines, we developed a [3 + 2] cycloaddition/1,3-H shift/rearrangement/dehydrogenation cascade involving in situ generated CF 3 CHN 2 and 3-ylideneoxindoles with DBU as a base. The reaction is distinguished by its mild conditions, metal-free process, operational simplicity, and broad functional group tolerance, thus presenting a convenient protocol for the construction of pyrazolo[1,5- c ]quinazolines that are of interest in medicinal chemistry., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Objectives: To investigate in vive osteogenic potential in size-critical bone defect after percutaneous autologous grafting of culture-expanded rabbit autologous BMSCs, osteo-induced BMSCs and combination of both., Methods: BMSCs were cultured and then induced with osteogenic supplement (OS) medium. BMSCs with and without OS induction were collected and percutaneously autologously injected respectively into the 15 mm bone defect of 20 experimental rabbit model. The grafts were BMSCs, osteo-induced BMSCs, BMSCs and osteo-induced BMSCs, BMP combined with fibrin sealant, and 0.9% NaCl solution. Osteogenesis at the defect areas were observed by regular radiography, histology and biomechanics., Results: The group transplanted with BMSCs + osteo-induced BMSCs achieved complete bone healing with medullary cavity united, which showed the largest quantity of new bone measured by X-ray analysis, and also their maximal load were better than those in other groups., Conclusion: The bone-forming ability of rabbit osteo-induced BMSCs combined with BMSCs in bone defect is superior to those of BMSCs and osteo-induced BMSCs.

Objective: To evaluate the scanning technique and primary clinical value of sixteen-slice spiral CT coronary angiography., Methods: Plain and enhanced sixteen-slice spiral CT imaging was performed in 69 patients, including 64 cases of suspected coronary heart disease and 5 cases of coronary stent. Calcium scoring with plain scan images and MPR, MIP and VRT reconstruction with enhanced scan images were made in all cases, among which 10 underwent conventional coronary angiography. The demonstration and stenosis of coronary arteries were evaluated. The factors influencing the image quality were analyzed. Additional MPR and MIP reconstruction of slices perpendicular to the stent and virtual endoscopy of stent were made in 7 stents of the 5 cases of coronary stent. The patency of the stents was evaluated., Results: A four-step scanning procedure was devised. Coronary calcium score could be got by plain scanning with sixteen-slice spiral CT angiography. All of the primary, most of the secondary and tertiary, and part of the fourth level branches of coronary artery could be shown isotropically with MPR, MIP and VRT reconstruction images of enhanced scanning. MPR and MIP were better than VRT in demonstrating small branches. Evaluated by VRT image, the image quality of 79.7% of the patients were first class, 10.1% second class, and 10.1% third class. The image quality was correlated to the contrast concentration in the root of aorta, heart rate, existence or absence of arrythmia, and the patient's breath-holding ability. Stenosis of coronary arteries was evaluated by sixteen-slice spiral CT imaging in 10 cases, with a result comparable to that by conventional coronary angiography. The stents were well shown, six stents being evaluated as patent, while one not., Conclusion: Sixteen-slice spiral CT coronary angiography is a noninvasive, simple and good method. Coronary calcium score and coronary artery stenosis can be evaluated with one study. The patency of stents can also be evaluated.