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121.
Reaction of 2 with bis(tributyltin) in the presence of 3 mol % Pd2(dba)3, 6 mol % XPhos, and 30 equiv of LiBr in wet and air bubbled THF at reflux for 8 h afforded the desired products 3 in 73–74% yields. The cross-coupling reaction of 3a with aryl iodides in the presence of 10 mol % Pd(PPh3)4 and 10 mol % CuI afforded the coupled products 4a–p in 47–90% yields. The coupling reaction of 3b with various alkynyl bromides having aryl-, alkyl, or trialkylsilyl group also afforded the corresponding 1,3-enynes 5a–g in 61–77% yields. 相似文献
122.
Simultaneous determination of nine lignans from Schisandra chinensis extract using ultra‐performance liquid chromatography with tandem mass spectrometry in rat plasma,urine, and gastrointestinal tract samples: Application to the pharmacokinetic study of Schisandra chinensis 下载免费PDF全文
You‐Jin Kim Hee Ju Lee Chul Young Kim Sun‐Young Han Young‐Won Chin Young Hee Choi 《Journal of separation science》2014,37(20):2851-2863
The fruit of Schisandra chinensis is a well‐known herbal medicine and dietary supplement due to a variety of biological activities including antihepatotoxic and antihyperlipidemic activities. However, the simultaneous validation methodology and pharmacokinetic investigation of nine lignans of S. chinensis extract in biological samples have not been proved yet. Thus, the present study was undertaken to develop the proper sample preparation method and simultaneous analytical method of schisandrol A, gomisin J, schisandrol B, tigloylgomisin H, angeloylgomisin H, schisandrin A, schisandrin B, gomisin N, and schisandrin C in the hexane‐soluble extract of S. chinensis to apply for the pharmacokinetic study in rats. All intra‐ and interprecisions of nine lignans were below 13.7% and accuracies were 85.1–115% and it is enough to evaluate the pharmacokinetic parameters after both intravenous and oral administration of hexane‐soluble extract of S. chinensis to rats. 相似文献
123.
Xie Ju Yang Yanwu Xi Ziqing Yang Zhenshan Zhang Xuecheng Ni Lubin 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(9-10):751-761
Journal of Inclusion Phenomena and Macrocyclic Chemistry - The combination of the electron donor and acceptor into a donor–acceptor system can transform the intermolecular charge transfer... 相似文献
124.
Zeng Fuping Zhu Kexin Chen Xiaoyue Li Haotian Guo Xinnuo Feng Xiaoxuan Li Long Yao Qiang Tang Ju 《Plasma Chemistry and Plasma Processing》2022,42(6):1361-1380
Plasma Chemistry and Plasma Processing - Accurately grasping the decomposition path of SF6 on the surface of typical metals and metal oxides is the key to reveal the decomposition mechanism of... 相似文献
125.
Russian Journal of Organic Chemistry - (Z)-2-(5-Amino-1,2,4-thiadiazole-3-yl)-2-(methoxyimino)acetic acid, an important intermediate product in the synthesis of Ceftobiprole, was prepared... 相似文献
126.
Russian Journal of Organic Chemistry - N-Aryl anthranilic acid drugs have been synthesized by a simple, environmentally friendly, low-cost, and high-yielding modified Ullmann coupling reaction... 相似文献
127.
An efficient tandem route to obtain tetrasubstituted NH pyrroles in a one-pot manner has been developed, staring from simple nitriles, ethyl bromoacetates, and zinc. This reaction involves oxidative dimerization of the zinc bromide complex of β-enaminoesters using cerium ammonium nitrate (CAN) as an oxidant, affording 2,3,4,5-tetrasubstituted pyrroles in yields up to 91%. 相似文献
128.
Enhanced Static Modulated Fourier Transform Spectrometer for Fast Approximation in Field Application
We discuss the data sampling frequency, the spectral resolution, and the limit for non-aliasing in the static modulated Fourier transform spectrometer based on a modified Sagnac interferometer. The measurement was performed in a very short 4 ms, which is applicable for real time field operation. The improved spectrometer characteristics were used to investigate the spectral properties of an InGaAs light emitting diode. In addition, The measured spectral peak was shifted from 6420 cm−1 to 6365 cm−1, as the temperature increased from 25 °C to 40 °C, when the operating current is fixed to be 0.55 A. As the applied current increased from 0.30 A to 0.55 A at room temperature, the spectral width was broadened from 316 cm−1 to 384 cm−1. Compared to the conventional Fourier transform spectrometer, the measured spectral width by the static modulated Fourier transform spectrometer showed a deviation less than 10%, and the spectral peak shift according to the temperature rise showed a difference within 2%. 相似文献
129.
A direct, reagent-free, ultraviolet spectroscopic method for the simultaneous determination of nitrate (NO3−), nitrite (NO2−), and salinity in seawater is presented. The method is based on measuring the absorption spectra of the raw seawater range of 200–300 nm, combined with partial least squares (PLS) regression for resolving the spectral overlapping of NO3−, NO2−, and sea salt (or salinity). The interference from chromophoric dissolved organic matter (CDOM) UV absorbance was reduced according to its exponential relationship between 275 and 295 nm. The results of the cross-validation of calibration and the prediction sets were used to select the number of factors (4 for NO3−, NO2−, and salinity) and to optimize the wavelength range (215–240 nm) with a 1 nm wavelength interval. The linear relationship between the predicted and the actual values of NO3−, NO2−, salinity, and the recovery of spiked water samples suggest that the proposed PLS model can be a valuable alternative method to the wet chemical methods. Due to its simplicity and fast response, the proposed PLS model can be used as an algorithm for building nitrate and nitrite sensors. The comparison study of PLS and a classic least squares (CLS) model shows both PLS and CLS can give satisfactory results for predicting NO3− and salinity. However, for NO2− in some samples, PLS is superior to CLS, which may be due to the interference from unknown substances not included in the CLS algorithm. The proposed method was applied to the analysis of NO3−, NO2−, and salinity in the Changjiang (Yangtze River) estuary water samples and the results are comparable with that determined by the colorimetric Griess assay. 相似文献
130.
Hun Ho Park Junseong Park Hye Joung Cho Jin-Kyoung Shim Ju Hyung Moon Eui Hyun Kim Jong Hee Chang Soo Youl Kim Seok-Gu Kang 《Molecules (Basel, Switzerland)》2021,26(2)
Resident cancer cells with stem cell-like features induce drug tolerance, facilitating survival of glioblastoma (GBM). We previously showed that strategies targeting tumor bioenergetics present a novel emerging avenue for treatment of GBM. The objective of this study was to enhance the therapeutic effects of dual inhibition of tumor bioenergetics by combination of gossypol, an aldehyde dehydrogenase inhibitor, and phenformin, a biguanide compound that depletes oxidative phosphorylation, with the chemotherapeutic drug, temozolomide (TMZ), to block proliferation, stemness, and invasiveness of GBM tumorspheres (TSs). Combination therapy with gossypol, phenformin, and TMZ induced a significant reduction in ATP levels, cell viability, stemness, and invasiveness compared to TMZ monotherapy and dual therapy with gossypol and phenformin. Analysis of differentially expressed genes revealed up-regulation of genes involved in programmed cell death, autophagy, and protein metabolism and down-regulation of those associated with cell metabolism, cycle, and adhesion. Combination of TMZ with dual inhibitors of tumor bioenergetics may, therefore, present an effective strategy against GBM by enhancing therapeutic effects through multiple mechanisms of action. 相似文献