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1.
Yong-Li Li Qiang Zhang Jian-Jun Wu Li-Jun Xue Li-Ming Chen Jun-Mian Tian Zhuo-Ni Xu Ying Chen Xian-Wen Yang Xiao-Jiang Hao Jie Li 《Tetrahedron letters》2019,60(10):751-753
From Abies nukiangensis, two novel 13,14-seco-abietane diterpenes, nukiangendines A (1) and B (2) were isolated. Their relative structures were determined by extensive NMR and HRMS spectroscopic analysis. The absolute configuration of 1 was established by ECD calculations. Compound 1 showed significant anti-hepatitis C virus (HCV) effects. 相似文献
3.
Haiying Yang Zhejian Li Meng Shan Congcong Li Honglan Qi Qiang Gao Jinyi Wang Chengxiao Zhang 《Analytica chimica acta》2015
A highly selective and sensitive electrogenerated chemiluminescence (ECL) biosensor for the detection of prostate PC-3 cancer cells was designed using a prostate specific antibody as a capture probe and ruthenium complex-labelled wheat germ agglutinin as a signal probe. The ECL biosensor was fabricated by covalently immobilising the capture probe on a graphene oxide-coated glassy carbon electrode. Target PC-3 cells were selectively captured on the surface of the biosensor, and then, the signal probe was bound with the captured PC-3 cells to form a sandwich. In the presence of tripropylamine, the ECL intensity of the sandwich biosensor was logarithmically directly proportion to the concentration of PC-3 cells over a range from 7.0 × 102 to 3.0 × 104 cells mL−1, with a detection limit of 2.6 × 102 cells mL−1. The ECL biosensor was also applied to detect prostate specific antigen with a detection limit of 0.1 ng mL−1. The high selectivity of the biosensor was demonstrated in comparison with that of a lectin-based biosensor. The strategy developed in this study may be a promising approach and could be extended to the design of ECL biosensors for highly sensitive and selective detection of other cancer-related cells or cancer biomarkers using different probes. 相似文献
4.
Liu Wei Zhang Daohong Zhu Wenxin Zhang Sikai Wang Yashan Yu Shaoxuan Liu Tao Zhang Xiao Zhang Wentao Wang Jianlong 《Mikrochimica acta》2015,182(1-2):401-408
Microchimica Acta - We describe a method for the visual and colorimetric determination of total nereistoxin-related insecticide residues. It is based on the nereistoxin-induced aggregation of gold... 相似文献
5.
Six known compounds, isoroquefortine C (1), griseofulvin (2), ergosterol peroxide (3), 3β-hydroxy-(22E,24R)-ergosta-5,8,22-trien-7-one (4), cerevisterol (5) and (22E,24R)-6β-methoxyergosta-7,22-diene-3β,5α-diol (6), were produced by the fungus Penicillium brasilianum, and their structures were elucidated by spectroscopic methods. This is the first report on isoroquefortine C as naturally occurring compound. Their bioactivities against five phytopathogenic fungi (Gibeberalla saubinetti, Fusarium solani, Botrytis cinerea, Colletotrichum gloeosporioides and Alternaria solani) and four pathogenic bacteria (Escherichia coli, Bacillus subtilis, Staphyloccocus aureus and Bacillus cereus), as well as allelopathic activities on Raphanus sativus were tested. Compound 1 exhibited a remarkable antifungal activity with minimum inhibitory concentration (MIC) of 12.5 μM against C. gloeosporioides, in comparison with positive control hymexazol (MIC 25 μM). Compound 2 displayed strong inhibitory effects on the growth of A. solani and S. aureus with MIC of 3.13 μM for each. Compounds 2 and 3 displayed a significant growth-inhibition activity on R. sativus. 相似文献
6.
《中国化学快报》2022,33(10):4563-4566
Nano-drug delivery systems with multiple stimulus-responsive capabilities have superior response performance and efficient drug release. Nevertheless, it is sophisticated to construct multiple stimulus-responsive systems where the two or more functional groups need to be introduced simultaneously. Xanthate, one functional group with pH and H2O2 stimulus responsiveness, has significant potential applications for building dual-responsive drug delivery system. Herein, we present a novel dual stimuli-responsive supramolecular drug delivery system by using sodium xanthate derivative (SXD) as guest molecule and quaternary ammonium capped pillar[5]arene (QAP5) as host molecule through host-guest interaction on the basis of electrostatic interaction. The amphiphile QAP5?SXD could self-assemble into vesicles to efficiently load the anti-cancer drug DOX. The experimental results showed that QAP5?SXD nanoparticles could achieve efficient drug delivery and controlled release in the tumor microenvironment. Cytotoxicity experiments proved that DOX@QAP5?SXD nanoparticles could significantly improve the anticancer efficiency of free DOX on cancer cells. The present study provides an efficient strategy to develop supramolecular nanocarriers with dual-responsiveness in one functional group for controlled drug release. 相似文献
7.
Jia Wen Pengyi Xiaa Ziming Zhenga Yongqian Xua Hongjuan Lia Fengyu Liub Shiguo Suna 《中国化学快报》2017,28(10):2005-2008
The pH values of lysosomes in cancer cells is slightly lower than that in normal cells, which can be used to distinguish cancer cells from normal cells. According to this, a naphthalimide-rhodamine based fluorescent probe(hereafter referred to as RBN) with a pK_a of 4.20 was designed and synthesized for ratiometric sensing of cellular pH via fluorescence resonance energy transfer(FRET), which can respond to different pH precisely through ratiometric fluorescence intensity(Ⅰ_(577)/Ⅰ_(540)). RBN can be employed to distinguish cancer cells from normal cells on the basis of different fluorescent response, in particular, RBN showed excellent water solubility and low cell toxicity, all these are quite significant for potential application in cancer diagnose and therapy. 相似文献
8.
9.
Xiaolong Wan Jiadong Hu Dongyang Xu Yang Shang Yanxia Zhen Chenchen Hu Fan Xiao Yu-Peng He Yisheng Lai Weiqing Xie 《Tetrahedron letters》2017,58(12):1090-1093
A Re2O7 catalyzed cycloetherification of monoallylic diols is described. The reaction features short reaction time, mild reaction conditions and exclusive E selectivity. A wide range of monoallylic alcohols with alkyl or aryl substituents on olefin smoothly undergo ring closure to deliver corresponding oxa-heterocycles. The reaction is also operationally simple and not sensitive to air and moisture. 相似文献
10.
Shunbo Yang Zhipeng Meng Yanan Li Rongxin Chen Yazhou Yang Zhengyang Zhao 《Molecules (Basel, Switzerland)》2021,26(4)
‘Orin’ is a popular apple cultivar, which has a yellow-green appearance, pleasant taste, and unique aroma. However, few studies on the fruit quality characteristics of ‘Orin’ apples have been reported before. In this study, changes of the physiological characteristics were measured at different ripening stages, and the soluble sugars and organic acids were determined by high-performance liquid chromatography (HPLC). Volatile compounds were identified using the headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). During the fruit ripening, the ‘Orin’ apple fruit weight, size, and total soluble solid were gradually increased by contrast with the titratable acidity, and the firmness decreased. The content of four soluble sugars reached the maximum at the 180 days after full bloom (DAFB) stage. Malic acid was measured as the most abundant organic acid in ‘Orin’ apples. Ethyl butyrate, hexyl propanoate, hexyl acetate and butyl acetate belonging to esters with high odor activity values (OAVs) could be responsible for the typical aroma of ‘Orin’ apples. The aim of this work was to provide information on the flavor characteristics of ‘Orin’ apples and promote this apple cultivar for marketing and processing in the future. 相似文献