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991.
992.
993.
In this work,important commercial pharmaceutical intermediates,phenylpropionic acid compounds,are successfully obtained by catalyzing the reaction of carbon dioxide with phenyl halides using MOF-5,a typical metal-organic framework(MOF)material.The influence of temperature,pressure,catalyst type and light on the reaction is investigated,and a 90.3%selectivity towards fluorophenylpropionic acid is reached.Significantly,the catalysts are effective for varied benzyl compounds containing different substituent groups.The catalysts are stable and remain active after three cycles. 相似文献
994.
Sheng-Chieh Wang Meng-Yang Chang Jun-Ping Shiau Ammad Ahmad Farooqi Yu-Hsiang Huang Jen-Yang Tang Hsueh-Wei Chang 《Molecules (Basel, Switzerland)》2022,27(5)
The benzo-fused dioxabicyclo[3.3.1]nonane core is the central framework in several natural products. Using this core, we had developed a novel nitrated [6,6,6]tricycle-derived compound containing an n-butyloxy group, namely, SK2. The anticancer potential of SK2 was not assessed. This study aimed to determine the antiproliferative function and investigated possible mechanisms of SK2 acting on oral cancer cells. SK2 preferentially killed oral cancer cells but caused no harmful effect on non-malignant oral cells. After the SK2 exposure of oral cancer cells, cells in the sub-G1 phase accumulated. This apoptosis-like outcome of SK2 treatment was validated to be apoptosis via observing an increasing annexin V population. Mechanistically, apoptosis signalers such as pancaspase, caspases 8, caspase 9, and caspase 3 were activated by SK2 in oral cancer cells. SK2 induced oxidative-stress-associated changes. Furthermore, SK2 caused DNA damage (γH2AX and 8-hydroxy-2′-deoxyguanosine). In conclusion, a novel nitrated [6,6,6]tricycle-derived compound, SK2, exhibits a preferential antiproliferative effect on oral cancer cells, accompanied by apoptosis, oxidative stress, and DNA damage. 相似文献
995.
Tubulin inhibitors can interfere with normal cell mitosis and inhibit cell proliferation through interfering with the normal structure and function of microtubules, forming spindle filaments. Indole, as a privileged pharmacological skeleton, has been widely used in anti-cancer inhibitors. A variety of alkaloids containing an indole core obtained from natural sources have been proven to inhibit tubulin polymerization, and an ever-increasing number of synthetic indole-based tubulin inhibitors have been reported. Among these, several kinds of indole-based derivatives, such as TMP analogues, aroylindoles, arylthioindoles, fused indole, carbazoles, azacarbolines, alkaloid nortopsentin analogues and bis-indole derivatives, have shown good inhibition activities towards tubulin polymerization. The binding modes and SARs investigations of synthetic indole derivatives, along with a brief mechanism on their anti-tubulin activity, are presented in this review. 相似文献
996.
高效液相色谱法测定忍冬藤和叶中8种活性成分 总被引:1,自引:0,他引:1
建立了多波长分析忍冬藤和叶中化学成分含量的高效液相色谱分析方法,色谱柱为Aglient Zorbax80A,Extend-C18(4.6mm×250mm,5μm);流动相为0.3%甲酸-乙腈,梯度洗脱;流速为1.5mL/min;检测波长为240、330、360nm;柱温38℃。各指标成分的检出限均低于0.29mg/L;精密度RSD均低于2.29%;标准加入的回收率为91.2%~103.6%。应用新建立的方法测定了7个不同产地忍冬藤和叶中8种活性成分的含量。该方法简单、快速、准确,可用于忍冬藤和叶的质量控制。 相似文献
997.
高效阴离子交换色谱分离-脉冲安培检测法测定烟草料液中的糖、糖醇和醇类化合物 总被引:6,自引:0,他引:6
建立了高效阴离子交换色谱分离-脉冲安培检测法测定烟草料液中的糖、糖醇以及醇类化合物的方法。以NaOH为淋洗液,在CarboPac MA1阴离子交换柱上等度分离了肌醇、甘油、丙二醇、半乳糖醇、木糖醇、山梨醇、甘露醇、葡萄糖、果糖、蔗糖、甘露糖和半乳糖等12种化合物。对影响分离和检测的条件进行了优化,并在此优化条件下分析了烟草料液中的糖、糖醇以及醇类化合物。12种化合物的检出限为2.0~216μg/L(25.0μL进样,以3倍信噪比计算检出限)。12种化合物浓度为1~5mg/L的标准溶液连续7次进样的RSD为0.7%~4.3%。方法对烟草料液中12种化合物的加标回收率为80%~108%。方法灵敏、高效、简便、快捷。 相似文献
998.
宽禁带半导体β-Ga2O3因为具有优良的物理化学性能而成为研究热点.本文基于DFT(Density Functional Theory)的第一性原理方法,先采用PBE(Perdew-Burke-Ernzerhof)中的GGA(Generalized Gradient Approximation)和GGA+U(Generalized Gradient Approximation-Hubbard U)的方法计算了本征β-Ga2O3,Lu掺杂浓度为12.5%的β-Ga2O3及Lu-Eu共掺杂浓度为25%的β-Ga2O3结构的晶格常数、能带结构和体系总能量.发现采用GGA+U的方法计算的带隙值更接近实验值,于是采用GGA+U的方法计算了本征β-Ga2O3,Lu掺杂的β-Ga2O3以及Lu-Eu共掺杂的β-Ga2O... 相似文献
999.
1000.
Hui-Min Liu Sheng-Nan Lei Wei Tang Meng-Han Xun Zhi-Wei Zhao Ming-Yan Cheng Xiao-Dan Zhang Wei Wang 《Molecules (Basel, Switzerland)》2022,27(6)
In this study, ultrasonic-assisted cellulase extraction (UCE) was applied to extract flavonoids and polyphenols from the Nymphaea hybrid flower. The extraction conditions were optimized using the response surface method (RSM) coupled with a Box-Behnken design. The crude extract of Nymphaea hybrid (NHE) was further purified using AB-8 macroporous resins, and the purified extract (NHEP) was characterized by FTIR and HPLC. In vitro activity determination by chemical method showed that NHEP displayed strong free radical scavenging abilities against the DPPH and ABTS radicals, good reduction power, and hyaluronidase inhibition. The cell viability by CCK-8 assays showed that NHEP had no significant cytotoxicity for B16 and HaCaT cells when the concentration was below 100 μg/mL and 120 μg/mL, respectively. NHEP with a concentration of 20–160 μg/mL can more effectively reduce the ROS level in H2O2 damaged HaCaT cells compared with 10 μg/mL of VC. The 40 μg/mL of NHEP had similar activity against intracellular melanin production in the B16 melanoma cells compared with 20 μg/mL Kojic acid. Good activities of antioxidation, whitening and protective effect against H2O2-induced oxidative damage promote the potential for NHEP as a functional raw material in the field of cosmetics and medicine. 相似文献