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A variety of pyran-fused isoquinoline derivatives were prepared in moderate to good yields through the rhodium-catalyzed dual C–H functionalization/annulation of methyl benzimidates and diazo compounds. A one-pot procedure, broad substrate scope, diversified products, and mild reaction conditions make this transformation a powerful tool for the synthesis of fused heteroarenes. In addition, the synthetic application was extended by large-scale synthesis and late-stage functionalization via Pd-catalyzed Suzuki–Miyaura, Heck, and Sonogashira cross-coupling reactions. Furthermore, a photophysical survey reveals that the pyran-fused isoquinoline products exhibit fluorescence properties and show potential for exploring fluorescent material applications. [ABSTRACT FROM AUTHOR]

Background & Aims: Patients with obstructive jaundice (OJ) are considered to be prothrombotic with increased risk of thromboembolism complications. The role of neutrophil extracellular traps (NETs) in procoagulant activity (PCA) and thrombosis risk in patients with OJ is unclear. In this study, we investigated NETs formation in OJ patients and the role of elevated unconjugated bilirubin (UCB) in inducing NETs, resulting in enhanced PCA and endothelial injury. Methods: NETs of OJ patients and healthy controls were measured. NETs PCA was assessed via coagulation time (CT), fibrin formation and purified coagulation complex production assays. Visualization of NETs and mitochondrial reactive oxygen species (MitoROS) were performed with a fluorescence microscope. We further used confocal microscopy to quantify the exposure of phosphatidylserine (PS), fibrin strands and FVa/Xa on Human umbilical vein endothelial cells (HUVECs). Results: Assessment of NETs components levels revealed greater NETs production in OJ patients than in healthy controls. Importantly, OJ‐NETs were responsible for enhanced PCA. UCB induced NETs formation via MitoROS accumulation and mitochondrial mobilization. HUVECs cocultured with OJ NETs lost their cell–cell junctions and consequently converted to a procoagulant phenotype. The PCA was attenuated by using DNase I alone or in combination with lactadherin. Conclusions: Our results suggest that UCB‐induced NETs play a prominent role in promoting the hypercoagulable and prothrombotic state in OJ patients. The increased MitoROS accumulation in neutrophils initiated NETosis. NETs are promising targets for indicating or improving coagulation disorders in OJ patients. [ABSTRACT FROM AUTHOR]

An efficient and practical strategy for the construction of pyrrolo[3,4- c ]isoquinolines via Rh(III)-catalyzed cascade C-H activation and subsequential annulation process from easily available O -methyl aryloximes and maleimides has been disclosed. This facile protocol does not require any inert atmosphere protection with good efficiency in a low loading of catalyst and exhibits good functional group tolerance and broad substrate scope. Notably, the as-prepared products show potential photophysical properties.

A cascade annulation strategy triggered by rhodium(III)-catalyzed C-H activation has been reported for the expeditious assembly of pyrrolidinedione-fused 1,2-benzothiazines from free NH-sulfoximines with maleimides under mild conditions. Without the need for inert atmosphere protection, a broad range of sulfoximines with maleimides were well tolerated, producing diverse fused-thiazine derivatives in moderate to good yields. Additionally, the late-stage transformation of the target product demonstrated the potential synthetic value of this protocol.

A Rh(III)-catalyzed cascade nucleophilic addition/intramolecular annulation of 2-diazo-1,3-diketones with 1,3-dicarbonyl compounds (e.g., 1,3-diketones and β-keto esters) is achieved to afford 6,7-dihydrobenzofuran-4(5 H )-ones in up to 91% yields. Notably, a wide range of substrates and functional groups were well-tolerated under the optimized reaction conditions to give desired products in moderate to excellent yields with release of N 2 and H 2 O as byproducts. Moreover, the method described is scalable and adaptable to late-stage functionalization.

Efficient access to 8 H -isoquinolino[1,2- b ]quinazolin-8-ones and phthalazino[2,3- a ]cinnoline-8,13-diones through cyclic amide-directed Ru(II)/Ir(III)-catalyzed C-H bond activation, has been developed. Consecutive C-H bond activation, carbene insertion, and condensation annulation processes were realized, affording 8 H -isoquinolino[1,2- b ]quinazolin-8-one and phthalazino[2,3- a ]cinnoline-8,13-dione derivatives in good-to-excellent yields under mild conditions, with H 2 O and N 2 being generated as the only byproducts., Competing Interests: The authors declare no competing financial interest.

Adipose-derived stem cells (ASCs) appear to be a useful stem cell population, which has been shown to possess multipotentiality. The aim of this study was to evaluate the utility of ASCs in tissue-engineered cartilage using a hybrid scaffold from fibrin-modified PLGA scaffold. ASCs were isolated from rabbit adipose tissue. The PLGA scaffold was prepared by low-temperature deposition technology and the hybrid scaffold was fabricated by a freeze-drying method. When ASCs were seeded onto fibrin-modified PLGA scaffold in vitro, enhanced cellular viability was observed compared to unmodified PLGA scaffold. The analysis of proteoglycan and collagen II revealed that fibrin-modified scaffold succeeded in inducing ASCs to differentiate into chondrocytes in vitro. A preliminary study on cartilage regeneration was also performed in vivo. Observation of histology and immunoblotting demonstrated that ASCs containing the hybrid scaffold promoted cartilage regeneration in the defects of articular cartilage much better than other groups. These results indicated that ASCs containing the hybrid scaffold are a more effective way to potentially enhance articular cartilage regeneration.