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91.
92.
The realistic shell model Hamiltonians, USD and GXPF1A, have been transformed from the particle-particle (normal) representation to the particle-hole representation (multipole-multipole) by using the known formulation in Ref. [1]. The obtained multipole-multipole terms were compared with the known spherical tensor forces, including the coupled ones. It is the first time the contributions of the coupled tensor forces to the shell model Hamiltonian have been investigated. It has been shown that some coupled-tensor forces, such as r2Y2σ]1, also give important contributions to the shell model Hamiltonian. 相似文献
93.
A series of novel 2-hydrazinylpyrido[2,3-b]pyrazin-3(4H)-one derivatives were synthesized and evaluated for their cytotoxic activities against A549,MDA-MB-231 and HT-29 cell lines in vitro.Pharmacological data indicated that compounds 5b,5c,10a and 10g possessed marked cytotoxicity,especially 10a(with IC50 values of 0.81,2.56 and 1.63μmol/L against A549,MDA-MB- 23 1 and HT29 cell lines,respectively),which had emerged as a lead compound. 相似文献
94.
Molecular spectroscopic studies on the interaction of glycosaminoglycans with brilliant cresol blue and its analytical application. 总被引:1,自引:0,他引:1
Shuzhen Zhang Na Li Fenglin Zhao Ke'an Li Shenyang Tong 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(2):273-280
The interaction of brilliant cresol blue (BCB) with glycosaminoglycans (GAGs), such as heparin (Hep) and chondroitin 4-sulfate (CS), in aqueous solution has been studied by spectrophotometry and light scattering spectroscopy. Absorbance of BCB at 632 and 594 nm decreased on addition of Hep or CS with the appearance of a new blue-shifted absorption band at 550 nm, which indicated that new metachromatic complex formed. The linear decrease in absorbance of BCB at 632 nm was observed. In addition, Hep was more effective than CS (1.7 times) in decreasing absorbance of BCB. The stoichiometry of Hep or CS with BCB was determined by spectrophotometric titration and the MacIntosh extraction method. The result showed that the stoichiometry of BCB/Hep was 1.8 times that of BCB/CS. These results suggested that the interaction between GAGs and BCB was the result of electrostatic forces, and the differences between Hep and CS were attributed to the different negative charge numbers on repetitive disaccharides unit. Studies on the effects of alcohol and urea indicated that GAGs only interacted with the aggregates of BCB. Moreover, a strong light scattering signal was observed after mixing BCB with GAGs. Furthermore, the light scattering intensity at light scattering bands was proportional to the concentration of Hep or CS added when the concentration of BCB was constant. 相似文献
95.
The leaves and stems of Quercus variabilis Blume afforded a new cycloartane nortriterpenoid,3α-acetyloxy-4α,14α-dimethyl-9β, 19-cycloergost-24-oic acid(1),along with five known compounds(2-6).The structure of 1 was elucidated by 1D and 2D NMR and mass spectroscopy. 相似文献
96.
A new neophysalin,named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A(1),along with three other known neophysalins(2-4) were isolated from the calyxes of Physalis alkekengi L.var.francheti(Mast.) Makino.The structure of 1 was determined by means of 1D and 2D NMR,UV,IR and mass spectra.Compound 1 displayed potent cytotoxicities in vitro against PC- 3 and LNCaP cell lines. 相似文献
97.
Zhao Hua Wu Li Bo Wang Hui Yuan Gao Jian Huang Bo Hang Sun Shu Hui Li Li Jun Wu 《中国化学快报》2009,20(11):1335-1338
Three compounds were isolated from the tissue culture cells of Daphne giraldii cullus,their structures were identified as daphneolone(1),S-(+)-1-(4-hydroxy-3-methoxyphenyl)-3-hydroxy-5-phenyl-1-pentanone(2),S-(+)-1-(4-methoxyphenyl)-3- hydroxy-5-phenyl-1-pentanone(3),and among them,2 was a new compound,3 was a novel natural product. 相似文献
98.
Hai Yang Yu San Lin Jin Xue Zhang Yuan Liu Yang Fu Ou Nai Li Wang Xin Sheng Yao 《中国化学快报》2009,20(4):459-461
Two new benzophenone glucosides were isolated from the 60%ethanol extract of the dried stems of Cratoxylum cochinchinense. The structures were elucidated as 3-O-β-D-glucopyranosyl-2′,4,6′-trihydroxy-benzophenone and 3-O-β-D-glucopyranosyl-2′,5,6′-trihydroxybenzophenone on the basis of spectral and chemical methods. 相似文献
99.
A new protoberberine alkaloid,named 5,6-dihydro-10-hydroxy-2,3,9-trimethoxy-13-methyldibenzo[a,g]quinolizinium(1) was isolated from the 60%ethanol extract of the tubers of Corydalis yanhusuo W.T.Wang,together with a new natural product,13- methylpalmatrubine(2).Their structures were established by spectroscopic methods. 相似文献
100.
The dissociation constant of PAOx was determined spectro-photometrically in the presence or absence of surfactants. The state of PAOx in aqueous solutions was studied by using spectro-photometric and quantum chemical methods. The tautometric equilibrium is shifted to the quinone-hydrazone form in the presence of CTMAB. 相似文献