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951.
Up to now, the investigations of the chemistry of biliverdin and its analogs has been limited in organic solvents1-4. There is no report on organized molecular films of biliverdin and its derivatives. The structural organization and biophysical properties of biliverdin molecules in ordered molecular assemblies might be different from those in organic solvents, but similar to those in biological membranes in mammals. Therefore, biliverdin or its derivatives incorporated in ordered molecular fil… 相似文献
952.
Qing MU * Rong Wei TENG Chao Ming LI De Zu WANG Yu WU Han Dong SUN Chang Qi HU Phytochemistry Laboratory Kunming Institute of Botany Chinese Acadmy of Sciences Kunming School of Pharmacy Fudan University Shanghai 《中国化学快报》2001,(7)
Ongoing phytochemical studies on Goniothalamus species have led to the isolation of a number of annonaceous acetogenins and unusual new styryllactones which were found to possess significant cytotoxic activities against several hunan tumour cell lines1,2. Firstly, cyclopeptides were reported to be isolated from genus Goniothalamus in this paper.Goniothalamus leiocarpus is an evergreen tree which grows in the south of Yunnan, China. Four new anticancer styryllactones3,4 from the stem bark and… 相似文献
953.
Zhong Tao DING Jun ZHOU* Ning Hua TAN Shi Ming DENG Laboratory of Phytochemistry Kunming Institute of Botany Academia Sinica Kunming Department of Chemistry Yunnan University Kunming 《中国化学快报》2001,(8)
In our previous paper~(1-4), we have reported five new tetraglycosides (named prostratoside A-E) and a new cyclic peptide (named polycarponin A) from this plant. Our continuing study on the EtOAc soluble fraction of this plant led to the isolation of three new saikosaponin-like compounds: prostratoside F-H (1-3). This paper describes the structure elucidation of these three new compounds. Prostratosid F (1): white powder, mp. 186-188oC, [(]+22.0 (c 0.27, MeOH). Its HRFAB-MS gave a [… 相似文献
954.
A new naphthoquinoneimine derivative from the marine algal-derived endophytic fungus Aspergillus niger EN-13 总被引:2,自引:1,他引:2
Yi Zhang Xiao Ming Li Chang Yun Wang Bin Gui Wang 《中国化学快报》2007,18(8):951-953
Cultivation of an endophytic fungus Aspergillus niger EN-13 that was isolated from the inner tissue of the marine brown alga Colpomenia sinuosa resulted in the characterization of a new naphthoquinoneimine derivative,namely,5,7-dihydroxy-2-[1-(4- methoxy-6-oxo-6H-pyran-2-yl)-2-phenylethylamino]-[1,4]naphthoquinone.The structure of the new compound was established on the basis of various NMR spectroscopic analyses including 2D NMR techniques,EI-MS,and HR-ESI-MS.This compound displayed moderate antifungal activity. 相似文献
955.
In this work, we study the entropic uncertainty and quantum discord in two double-quantum-dot (DQD) system coupled via a transmission line resonator (TLR). Explicitly, the dynamics of the systemic quantum correlation and measured uncertainty are analysed with respect to a general X-type state as the initial state. Interestingly, it is found that the different parameters, including the eigenvalue α of the coherent state, detuning amount δ, frequency ω and the coupling constant g, have subtle effects on the dynamics of the entropic uncertainty, such as the oscillation period of the uncertainty. It is clear to reveal that the quantum discord and the lower bound of the entropic uncertainty are anti-correlated when the initial state of the system is the Werner-type state, while quantum discord and the lower bound of the entropic uncertainty are not anti-correlated when the initial state of the system is the Bell-diagonal state. Thereby, we claim that the current investigation would provide an insight into the entropic uncertainty and quantum correlation in DQDs system, and are basically of importance to quantum precision measurement in practical quantum information processing. 相似文献
956.
Ming Wang Xiangrui Meng 《计算数学(英文版)》2007,25(6):631-644
This paper proposes a robust finite element method for a three-dimensional fourth-order elliptic singular perturbation problem. The method uses the three-dimensional Morley element and replaces the finite element functions in the part of bilinear form corresponding to the second-order differential operator by a suitable approximation. To give such an approximation, a convergent nonconforming element for the second-order problem is constructed. It is shown that the method converges uniformly in the perturbation parameter. 相似文献
957.
WANG Ming 《Chinese Journal of Lasers》1995,4(6):521-529
AutomaticAnalysisofthePhaseObjectUsingProjectionMoireDeflectometry¥WANGMing(BasicDepartment,NanchangUniversity,Nanchang330029... 相似文献
958.
ItisgenerallyknownthatadditivityofmixedstationaryphasesinGCcanbeencoun-tered.Ourinvestigationshaveshowntheexistenceofsynergisticeffectintheside-chaincrownetherpolysiloxaneandperethylatedo-CDmixedstationaryphase,'resorcareneandcyclodextrinmixedstationaryphase,'aswellasinthemixedstationaryphasecon-sistingofheptakis(2,3,6-tri-o-pentyl)-o-CandAgNO3orT1NO,.'Ininorganicchemis-try,synergisticeffectshavebeenstudiedwidelyinextraction.'Theeffectsalsoexistintheextractionoforganiccompounds'andincapill… 相似文献
959.
Ying Hong ZHU Hui LOU* Ping LU Jia Geng LIU Xiao Ming ZHENG Chemistry Department Zhejiang University Hangzhou 《中国化学快报》2002,13(10)
Fluoroorganic compounds have been applied as useful intermediates in industry. Here, we use the PTC method for fluorination of aromatic halide by inorganic fluorides involv- ing a halogen-exchange. This is a convenient and attractive synthetic way to obtain fluoro compounds, because inorganic fluorides such as potassium fluoride is safe to be handled and cheap1. However, owing to poor solubilities of inorganic fluorides in organic solvents, the halogen-exchange fluorination often requires … 相似文献
960.
Inconnechonwith0urreeenteffortStowardsthesynthesis0fartificialreceptorsandenzymescontalninginddazoles",itwasnecessarytoprepareaclassofl-(orhaloalkyl)-inddazolesassyntheticpreeursors.The0nlyreportinliteratureislindtedforthepreparationofl-(2-bromoethyl)inddazolebyreactingimidazolefirstwithethylenecarbonate,thenwiththionylbr0nddet0givea24.5%yield'.Therearenogeneralpreparativemethodsforthesecompounds.RecenUy,HorvathreportedasimPlemethodf0rthepreparationofl-substitutedinddazolesfromaHoffmann-type… 相似文献