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101.
102.
在pH 11.2的B-R缓冲溶液中,吖啶橙与酵母核糖核酸形成缔合物,使酵母核糖核酸的共振散射增强。体系的最大散射波长为333nm,酵母核糖核酸的质量浓度在0.05~15.0mg·L-1范围内与共振散射增强强度(ΔI)呈线性关系,检出限(3s/k)为0.017mg·L-1。据此,提出了一种简单而快速测定酵母核糖核酸的方法。应用此方法测定2个空白合成样品中酵母核糖核酸的含量,测得平均回收率为99.0%,平均相对标准偏差(n=5)为1.3%。 相似文献
103.
Bin Li Chun-Mei Gao Qin-Sheng Sun Lu-Lu Li Chun-Yan Tan Hong-Xia Liu Yu-Yang Jiang 《中国化学快报》2014,25(7):1021-1024
Novel DNA binding agents against topoisomerases are needed for effective treatment of cancers. A series of new acridine-based derivatives 7a–7d were synthesized and their antiproliferative activity against K562 and HepG-2 cell lines were evaluated. Compound 7c with pyridin-2-yl-methanamino group substituted at the C9 position of acridine showed good antitumor activity against both cell lines. The DNA-binding affinity of compound 7c was evaluated by UV–vis absorption spectra and fluorescence emission spectra. DNA topoisomerase I mediated relaxation of plasmid pBR322 DNA was also tested. Our results suggested that compound 7c with good antitumor activity and topoisomerase I inhibition activity can be developed as a prime candidate for further chemical optimization. 相似文献
104.
Novel acridine spirocompounds, spiro[dihydroacridine-9′(10′H),5-imidazolidine]-2-thiones have been prepared by the spontaneous cyclization of 1-substituted 3-(acridin-9-ylmethyl)thioureas, which were obtained from 1-(acridin-9-yl)methanamine, N-(acridin-9-ylmethyl)propan-1-amine, and N-(acridin-9-ylmethyl)benzylamine and alkyl/aryl isothiocyanates, as continuation of our previous studies on new acridine spirocycles. Imidazolidine-2-thiones thus obtained were subsequently transformed with mesitylnitrile oxide to imidazolidine-2-one analogues, some of which partly reopened to the corresponding (acridin-9-ylmethyl)ureas. An unusual spirocyclization via a CH carbanion instead of the N-1 nitrogen has been found for 3-(acridin-9-ylmethyl)-1-(acridin-9-yl)thioureas possessing two acridine rings. Structural modifications in positions 1, 3, and 4 of the spiro ring together with 1H, 13C, and 15N NMR spectroscopy and X-ray crystallography have been employed to rationalize a general propensity of various 9-substituted acridines to undergo easy spirocyclization. 相似文献
105.
106.
在pH8.5和6.0的BR缓冲溶液中,吖啶橙(AO)和吖啶黄(AY)等碱性吖啶染料能与藻酸钠(SA)反应形成复合物,而使其共振瑞利散射RRS急剧增强并产生新的RRS光谱,其最大散射波长位于523nm(AO体系)和485nm (AY体系),藻酸钠浓度在0.075mg/L~5.0mg/L (AO体系)、0.25mg/L~3.0mg/ L(AY体系)时与散射强度(ΔI)呈直线关系,方法具有较高的灵敏度,其检出限分别为23.8ng/mL(AO体系),6.5ng/mL (AY体系).以吖啶橙体系为例研究了共存物质的影响,表明方法选择性好.用于海带提取液中藻酸钠的测定,结果满意. 相似文献
107.
Ece Altunbaş Şahin 《印度化学会志》2022,99(3):100358
The corrosion process commonly limits the use of copper in practical applications. The use of corrosion inhibitors is one of the effective methods to reduce the corrosion rate of copper. In this research, the inhibition effect of acridine orange (3,6-bis(dimethylamine)acridine) (AcO) for the protection of copper in 0.5 ?M ?H2SO4 solution was studied. For this aim, the change of open circuit potential with exposure time (Eocp-t), electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), anodic and cathodic potentiodynamic polarization measurements (PP) and chronoamperometry (CA) techniques were used. Some quantum chemical parameters (EHOMO, ELUMO and dipole moment) were calculated and discussed. The AcO film formed over the copper surface was examined by SEM, EDX, AFM and contact angle measurements. The electrochemical data showed that AcO is an effective corrosion inhibitor even at low concentrations (ranging between 99.1% and %99.4 ?at concentrations from 0.01 ?mM to 1 ?mM). The corrosion rate of copper decreases in the presence of the inhibitor by reducing both anodic and cathodic rates, which is depended on its concentration. This compound behaves as mixed-type corrosion inhibitors with predominantly cathodic type. Its adsorption on the copper surface obeys Langmuir adsorption isotherm. The value of adsorption equilibrium constant (Kads) and the standard free energy of adsorption were ΔGads 1.298 x 103 ?M?1 and -27.71 ?kJ/mol in the case of 0.5 ?M ?H2SO4 solution containing 1.0 ?mM AcO, which shows the adsorption is high and spontaneous. The adsorbed inhibitor film over the metal increase contact angle of the surface, which suggests the more hydrophobic properties of the surface are increasing coming from the orientation of hydrophobic sites to the electrolyte. The zero charge potential (Epzc) studies showed that the surface charge of the metal is positive in the corrosive media containing the inhibitor. Quantum chemical calculations showed that the binding of inhibitor molecules to the metal surface takes place through N atoms of the inhibitor. 相似文献
108.
《印度化学会志》2021,98(5):100057
A weak external magnetic field, very close to the hyperfine interactions of the system, can acts as a tool to monitor spin dynamics and assess distance between the components of the spin-correlated transient radical pair or radical ion pair (RIP). The present review focuses on the magnetic field effect (MFE) on the photo-induced electron-transfer (PET) reactions among acridine derivatives and classical as well as biological electron acceptor or donor moieties, which produce spin-correlated RIPs, in homogeneous solvents, heterogeneous micellar media and in biological nanocavities of proteins. Although a confined medium is preferred to observe prominent MFE, yet unanticipated MFE on PET between acridine derivatives [Acridone (AD) and Acridine Yellow (AY)] and classical electron donors is obtained even in homogeneous medium when it consists of impurities like water molecules. In a comparative study of interaction of another acridine derivative, Proflavin (PF+) with two electron donors which are amines of aromatic nature, MFE on PET reveal that the bulk and the structure of the electron donor govern the mechanism as well as the spin dynamics of PET. While studying interaction of PF+ with a different amine which is aliphatic in nature, MFE on PET implies that it is the nature of the solvent matrix which determines the spin dynamics of PET. The cause of discrepancy in the experimental and calculated values of B1/2 for 9-amino acridine – methyl viologen system has been delineated. Apart from micellar medium, prominent MFE on PET is also observed while studying the interaction of PF+, AY and AD with tryptophan residues present in the nanocavities of serum albumins since the inter-radical distance within primary geminate RIP is enough to make exchange interaction negligible. 相似文献
109.
The synthesis of various acridine-quinones is reported. The fluorescence-quenching quinone moiety has been incorporated into various acridine molecules, each having a different functionality at the ninth position of the acridine ring. It is envisaged that the quenching nature of the quinone will lead to the fluorescent properties of the acridine being controlled in a way similar to turning on a light switch. 相似文献
110.
吖啶橙(AO)-藏红T(ST)荧光探针测定DNA的研究 总被引:4,自引:1,他引:3
简述了以荧光能量转移本系测定DNA方法的发展过程,同时对吖啶(AO)-藏红T(ST)荧光探针测定DNA的条件进行分析,证明了该法灵敏度高、线性范围宽、检出限低、选择性好、抗干扰能力强,该法为微曦DNA测定分析工作提供了一个新的途径。 相似文献