α-Quaternary amino acids have found application in many biologically relevant compounds and pharmaceuticals. Although there are many methods for the synthesis of α-quaternary amino acids, most of them are mainly realized with the aid of transition metals and complex ligands. We present herein a 2,7-Br-4CzIPN catalyzed regioselective alkylation of azlactones with redox-active esters via radical-radical couplings.
View Article and Find Full Text PDFCp*Rh(III)-catalyzed nitro-directed C-H alkylation/alkenylation of nitroarenes has been reported for the first time. This protocol is associated with the features of high efficiency, broad substrate scope, and good functional group compatibility. Additionally, gram-scale experiments and synthetic applications proved the practicability of the method.
View Article and Find Full Text PDFRh (III)-catalyzed dienylation and cyclopropylation of 1,2,3-benzotriazinones with alkylidenecyclopropanes (ACPs) has been achieved. Different from the previous reports of 1,2,3-benzotriazinones, the triazinone ring remained intact in this C-H bond functionlization reaction. Also, the denitrogenative cyclopropylation could also be realized by changing the reaction temperature.
View Article and Find Full Text PDFHerein, we report a Rh(III)-catalyzed C4-selective activation of indoles by using iodonium ylides as carbene precursors. This protocol proceeded under redox neutral reaction conditions and provided important coupling products with good tolerance of functional groups and high yields. In addition, one-pot synthesis and scale-up and mechanistic studies were also conducted.
View Article and Find Full Text PDFObjectives: Vascularization is an essential step in successful bone tissue engineering. The induction of angiogenesis in bone tissue engineering can be enhanced through the delivery of therapeutic agents that stimulate vessel and bone formation. In this study, we show that cucurbitacin B (CuB), a tetracyclic terpene derived from Cucurbitaceae family plants, facilitates the induction of angiogenesis
Methods: We incorporated CuB into a biodegradable poly (lactide-co-glycolide) (PLGA) and β-tricalcium phosphate (β-TCP) biomaterial scaffold (PT/CuB) Using 3D low-temperature rapid prototyping (LT-RP) technology.
A tandem rhodium(III)-catalyzed system was established to access 3,4-dihydroisoquinolin-1(2)-one by coupling of -methoxy-3-methylbenzamide with 2-methylidenetrimethylene carbonate. This one-pot synthesis protocol processed smoothly under mild reaction conditions. Moreover, a total of 28 examples, broad substrate scope, and high functional-group compatibility were observed.
View Article and Find Full Text PDFA rhodium(III)-catalyzed C-H allylation of (hetero)arenes by using 2-methylidenetrimethylene carbonate as an efficient allylic source has been developed for the first time. Five different directing groups including oxime, -nitroso, purine, pyridine, and pyrimidine were compatible, delivering various branched allylarenes bearing an allylic hydroxyl group in moderate to excellent yields.
View Article and Find Full Text PDFIn this work, a novel reduction-responsive disulfide bond-containing cycloparaphenylene nanoring molecule (DSCPP) with a pyriform shape has been designed. In addition, the interactions between the designed nanoring (host) and fullerenes C and C (guests) were investigated theoretically at the M06-2X/6-31G(d,p) and M06-L/MIDI! levels of theory. By analyzing geometric characteristics and host-guest binding energies, it is revealed that the designed DSCPP is an ideal host molecule of guests C and C.
View Article and Find Full Text PDFBackground: The objective of the study was to investigate the effects of glucocorticoid (GC) on the fracture healing process in a closed femur fracture mice model.
Materials And Methods: Forty 12-week-old female CD-1 mice were randomly allocated into four groups: healthy control and mice with prednisone exposure (oral gavage), 6 mg/kg/day (GC-L), 9 mg/kg/day (GC-M) and 12 mg/kg/day (GC-H). Three weeks after the initiation of prednisone dosing, closed femur fractures were created on prednisone-exposed mice and the healthy control.
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View Article and Find Full Text PDFZhongguo Ying Yong Sheng Li Xue Za Zhi
February 2017
Objective: To research the hormone secretion levels of progesterone and estrogen and the gene expression levels of two go-nadotropin receptors follicle stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) in granular cells of laying hen, and the effect of culture time on the levels of hormone secretion and expression of related receptor gene in granulosa cells was inferred.
Methods: The experiment using the method of cells culture , the granular cells supernatants of hens were collected at 0 h, 24 h, 48 h, 72 h, 96 h, the progesterone and estrogen concentrations in cell supernatants were determined by ELISA kits, and detected the expression of FSHR and LHR gene in granular cells by real-time fluorescent quantitative PCR.
Results: The results showed that the progesterone and estrogen secretion reduced in the early culture of 0 h~48 h( < 0.
Noncovalent interactions involving aromatic rings, such as π···π stacking, CH···π are very essential for supramolecular carbon nanostructures. Graphite is a typical homogenous carbon matter based on π···π stacking of graphene sheets. Even in systems not involving aromatic groups, the stability of diamondoid dimer and layer-layer graphane dimer originates from C - H···H - C noncovalent interaction.
View Article and Find Full Text PDFAnion recognitions between common anions and a novel pincer-like receptor (N,N'-bis(5-fluorobenzoyloxyethyl)urea, BFUR) were theoretically explored, particularly on geometric features of the BFUR@X (X = F, Cl, Br, I, CO, NO, and SO) systems at a molecular level in this work. Complex structures show that two N-H groups as a claw and two -CF rings on BFUR as a pair of tweezers simultaneously interact with captured anions through cooperative double-dentate hydrogen bond and double-side anion-π interactions. The binding energies and thermodynamic information indicate that the recognitions of the seven anions by BFUR in vacuum are enthalpy-driven and entropy-opposed, which occur spontaneously.
View Article and Find Full Text PDFZhongguo Ying Yong Sheng Li Xue Za Zhi
September 2015
Objective: Isobaric tags for relative and absolute quantitation (iTRAQ) combined with mass spectrometry were used to screen differentially expressed plasma proteins in cold stress rats.
Methods: Thirty health SPF Wistar rats were randomly divided into cold stress group A and control group B, then A and B were randomly divided into 3 groups (n = 5): A1, A2, A3 and B1, B2, B3. The temperature of room raising was (24.
Ying Yong Sheng Tai Xue Bao
July 2015
The root system of tomato plant (Lycopersicon esculentum L. cv. Liaoyuanduoli) was treated with CO2 enrichment by aeroponical culture for 60 days.
View Article and Find Full Text PDFBasic fibroblast growth factor (bFGF) is a multifunctional factor in acceleration of cell proliferation, differentiation and transference, and therefore widely used in clinical applications. In this study, expression vector pWX-Nt03 harboring a codon-optimized bFGF gene was constructed and introduced into the tobacco chloroplasts by particle bombardment. After four rounds of selection, bFGF was proved to integrate into the chloroplast genome of regenerated plants and two of four transgenic plants were confirmed to be homoplastomic by PCR and Southern hybridization.
View Article and Find Full Text PDFA novel urea-based anion receptor with an electron-deficient aromatic structural unit, N-p-nitrophenyl-N-(4-vinyl-2-five-fluoro-benzoic acid benzyl ester)-phenyl-urea (FUR), was designed to probe the potential for halide-anion recognition through the cooperation of two distinct noncovalent interactions including hydrogen bonds and anion-π in this work. The nature of the recognition interactions between halide-anion and the designed receptor was theoretically investigated at the molecular level. The geometric features of the hydrogen bond and anion-π of the FUR@X(-) (X = F, Cl, Br, and I) systems were thoroughly investigated.
View Article and Find Full Text PDFTo observe the effects of insulin resistance on gonadal steroid hormone stimulation and the myometrial growth of female rats in order to elucidate the relationship between insulin resistance and the development of uterine leiomyomas. We divided 180 nonpregnant female Wistar rats into three groups as follows: group A, as the control group; group B, as the "model by exogenous sex hormone" group; and group C, as the "model by exogenous sex hormone plus insulin-resistance" group. All the animals were raised for 16 weeks.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
November 2006
The polyamidoamine dendrimers, PAMAM-CMAC, was synthesized by decorating PAMAM dendrimer with coumarin-3-methyl acyl chlorine on the periphery. The structures were characterized by FTIR and H-NMR spectra. The fluorescence analysis indicated the PAMAM-CMAC exhibits strong fluorescence emission.
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