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91.
92.
A number of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines were synthesized.The structures of these new compounds were confirmed by ~1H NMR,IR and elemental analysis.Biological evaluation in the greenhouse showed several compounds have good fungicidal activities at 25 mg/L. 相似文献
93.
Hui Fang Pi Peng Zhang Han Li Ruan Yong Hui Zhang Han Dong Sun Ji Zhou Wu 《中国化学快报》2009,20(11):1319-1320
A new alkaloid was isolated from the bulbs of Lycoris aurea(L'Herit.) Herb.Its structure was established as 3-o-ethyltazettinol through chemical and spectroscopic studies including 2D NMR. 相似文献
94.
Zhi NA Bei JIANG Hui YANG Zhong Wen LIN Han Dong SUN* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Chemistry Deparment of the College of Life Science Chemistry Yunnan University K 《中国化学快报》2001,(8)
Isodon enanderianus (Hand. -Mazz.) H. W. Li, has been used in folk medicine as anti-inflammatory and detoxified agent1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. In order to find more biologically active substances, we have carefully investigated the chemical constituents of I. enanderianus collected in Shiping county of Yunnan province, and as a result, enanderi… 相似文献
95.
Jing ZHAO Xiu Wei YANG Yu Xin CUI Xue Hui LIU Shu Yan LIU Hong Ying ZHI Ji Yong CHEN Fa Bing ZHU Yun Li XUE and Dian Bo LIU 《中国化学快报》1999,(4)
TheseedsofAesculuschinensisBge.(Hippocastanaceae)havebeenusedasfolkmedicineforthetreatmentofdistensionandpaininchestandabdomenl.Untilnow,thereisnoreportonitschemicalconstituents.Thispaperdescribesstructureelucidationoftwonewcompounds,escinsIVa3andIVb4onthebasisofspectroscopicmethodsandcomparisonwithescinsla1andfo22.Amongthem,EscinlaIwasstudiedbyX-raydistractionanalysis.Compound3,whitepowder,showediRbandsduetocarboxylanda,p-unsaturatedesterat1740,1713and1640cm-'andstrongabsorptionbandsat34… 相似文献
96.
Inrecentyearsmuchefforthasbeenspenttodevelopoligonucleotideanalogsashighlyselectivepharmaceuticalagentstoblockexpressionofdisease-associatedproteins'-'.andtheseefT'ortshaveresultedilltheapprovaloffomiversensodium(vitravene',"),thefirstantisensedrug,byFDAinAugust1998fortreatmentofAIDSpatientswithcytomegalovirus(CMV)-inducedretinitis6.However,thegreatpotentialofantisenseoligonucleotidesasantiviralandanticanceragentsiscompromisedbytheirnucleasesusceptibilityandlowcellmembranepermeability.L-D… 相似文献
97.
A Novel Palladium-Catalyzed Reaction and Its Application in Preparation of Derivatives of Stilbazols
Zhi Yong WANG* Chao JIANG Ji Hui WU Qing Xiang GUO Dept. of Chem. University of Science & Technology of China Hefei 《中国化学快报》2001,(5)
Many derivatives of stilbazoles have strong biological activities and pharmacological actions. For instance, (-substituent-(E)-4-styrylpyridines can be used as cytokinin analogues1. A series of N-substituted tetrahydro (phenylethenyl) pyridine derivatives were reported in vitro against both nicotinic and muscarinic receptors derived from rat cerebral cortax2. Therefore they can be used as candidates to develop new drugs for treatment of some diseases. On the other hand, this kind of compounds… 相似文献
98.
In this paper,the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ~1H NMR and ESI-MS.The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state,respectively,and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference.In concentration of>40 mmol/L,the duplex can gelate DMSO, and... 相似文献
99.
β2-Glycoprotein I(β2-GPI) has been identified as a cofactor in the recognition of phospholipid Ag cardiolipin (CL) by anticardiolipin Ab(aCL) purified from patients' serum with autoimmune disease. However, there is a considerable controversy as to the anti-β2-GPI -antibodies occurred in aCL. In order to select β2-GPI recognizing molecules, β2-GPI was used as a probe to screen affinity phage clones panned from a phage peptide library. After four cycles of selection, the phage recovery increased from 2.4×10-5% to 1.1×10-3%, indicating that a specific enrichment had been achieved. In order to characterize these phage clones, we investigated their specific binding to β2-GPI and their inhibition of β2-GPI binding to anti-β2-GPI antibodies. Almost 40 percent of clones reflected considerable binding abilities and inhibitory activities towards anti-β2-GPI antibodies. A group of related peptides were identified by DNA sequencing, in which there were seven related peptide sequences, with four of them representing more than once. These peptide sequences display similarities at several positions. Sequence motif (-F-S-L-) was evident in most of the peptides. It suggests that these peptides may specifically block the anti-β2-GPI antibodies binding to β2-GPI. Our result supports the idea that β2-GPI acts as a Ag for these anti-β2-GPI antibodies occurred in the aCL. 相似文献
100.
Zhi Hui Zhou Jian Hua Yang* Li Feng Chang Yan Zhang Wei Guo Sun Jin Qu Wang* State Key Laboratory of Fine Chemicals Institute of Adsorption Inorganic Membrane Dalian University of Technology Dalian PR China 《中国化学快报》2007,18(4):455-457
Novel NaA/carbon nanocomposite thin films were successfully prepared on a porous a-Al2O3 substrate by incorporatingnanosized NaA zeolite into novolak-type phenolic resin.The prepared films were characterized by XRD,SEM and single gaspermeation tests.The NaA zeolite/carbon nanocomposite thin films exhibited that the ideal separation factor of CO2/CH4 was 28.4and the carbon dioxide flux was 3.39*10-7mol/(Pa m2s)at room temperature and under a pressure difference of 100 kPa,whichwas two orders of magnitude higher than that of pure carbon membrane prepared at the same procedures and conditions as those ofcomposite films.From the SEM images,the films were continuous and highly intergrown.Compared with carbon membranes,thethickness of nanocomposite films was drastically decreased,which was helpful to reduce the diffusion resistance and increase theflux of gas permeance. 相似文献