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991.
992.
Synthesis and Biological Evaluation of Imidazo[2,1‐b][1,3,4]thiadiazole‐Linked Oxindoles as Potent Tubulin Polymerization Inhibitors
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Dr. Ahmed Kamal M. P. Narasimha Rao Pompi Das P. Swapna Sowjanya Polepalli Vijaykumar D. Nimbarte Kishore Mullagiri Jeshma Kovvuri Dr. Nishant Jain 《ChemMedChem》2014,9(7):1463-1475
A series of imidazo[2,1‐b][1,3,4]thiadiazole‐linked oxindoles composed of an A, B, C and D ring system were synthesized and investigated for anti‐proliferative activity in various human cancer cell lines; test compounds were variously substituted at rings C and D. Among them, compounds 7 ((E)‐5‐fluoro‐3‐((6‐p‐tolyl‐2‐(3,4,5‐trimethoxyphenyl)‐imidazo[2,1‐b][1,3,4]thiadiazol‐5‐yl)methylene)indolin‐2‐one), 11 ((E)‐3‐((6‐p‐tolyl‐2‐(3,4,5‐trimethoxyphenyl)imidazo[2,1‐b][1,3,4]thiadiazol‐5‐yl)methylene)indolin‐2‐one), and 15 ((E)‐6‐chloro‐3‐((6‐phenyl‐2‐(3,4,5‐trimethoxyphenyl)imidazo[2,1‐b][1,3,4]thiadiazol‐5‐yl)methylene)indolin‐2‐one) exhibited potent anti‐proliferative activity. Treatment with these three compounds resulted in accumulation of cells in G2/M phase, inhibition of tubulin assembly, and increased cyclin‐B1 protein levels. Compound 7 displayed potent cytotoxicity, with an IC50 range of 1.1–1.6 μM , and inhibited tubulin polymerization with an IC50 value (0.15 μM ) lower than that of combretastatin A‐4 (1.16 μM ). Docking studies reveal that compounds 7 and 11 bind with αAsn101, βThr179, and βCys241 in the colchicine binding site of tubulin. 相似文献
993.
根据我国最新的电力发展议案,国内的火力发电站都应该进行全面地改造,特别是一些生产用电和工业用电的大省。因此,整体钢结构的设计是必不可少的要素。本文主要从火电站主厂房钢结构的设计出发,研究了设计的方向和当中会出现的问题。 相似文献
994.
随着我国经济水平的持续提升和建筑工程整体水平的不断进步,在建筑工程中的深基坑施工质量监督工作得到了越来越广泛的应用。本文从对建筑工程中的深基坑施工质量问题进行了阐述,对建筑工程深基坑施工质量监督进行了分析。 相似文献
995.
根据我国最新的电力发展议案,国内的火力发电站都应该进行全面地改造,特别是一些生产用电和工业用电的大省。因此,整体钢结构的设计是必不可少的要素。本文主要从火电站主厂房钢结构的设计出发,研究了设计的方向和当中会出现的问题。 相似文献
996.
工程质量是企业素质的综合反映。树立“安全第一”的思想,抓生产必须抓安全,以安全促生产。因此,施工中必须要做好各项施工的质量、安全、文明、环境保护的保证措施。现就施工的质量、安全、文明、环境保护的保证措施谈些粗浅认识。 相似文献
997.
This paper deals with new and innovative case studies of application of post-tensioning for restoration of structures for buildings, bridges and rock stabilization in India. In earlier situations for these types of cases conventional method of repair and rehabilitation has been used. These innovative approaches for restoration have led to enormous saving of cost and time. The advantages of post tensioning are well known in the civil industry and are being used for the last 40 to 50 years. Post tensioning is one of the best methods to induce stresses in the concrete before application of live load and this technique can also be widely used for restoration and rehabilitation of structures. Unlike the use of post-tensioning in new structures there are no definite methods or codes for application in restoration and rehabilitation of structures. For restoration and rehabilitation of structures, PT (post tensioned) technique can be applied in combination with other techniques and materials available. Bridge lifting is a tricky and risky job especially when the superstructure is displaced appreciably by a natural calamity, etc.. Not only the present state of structure needs proper study before commencement of restoration and rehabilitation but also calls for careful execution. This paper deals with case studies of innovative applications of post tensioning in restoration and rehabilitation of structures and restoration of bridge structure in Andaman & Nicobar Island, India affected by Sumatra quake. 相似文献
998.
A finite element model for a piezoelectric plate with edge debonded actuators is presented. This model is employed to investigate the effect of edge debonding on actuation authority, natural frequencies and vibration control performance. The regions of the plate with the piezoelectric patches are modelled such that each layer undergoes rotation due to shear deformation independently. The necessary constraints for continuity of displacements at the interfaces of the layers are imposed. The plate with edge debonded actuators is idealized by dividing it into debonded regions and healthy regions. A finite element procedure for imposing the constraints regarding continuity of displacements at the interfaces of the adjacent regions is developed and is implemented using MATLAB. Experiments are conducted for finding the actuation authority and natural frequencies of the plate with debonded actuators. It has been found that the developed model has predicted the mechanics of actuator debonding properly. The investigations have revealed the fact that the edge debonding of actuators will result in considerable degradation in actuation authority and vibration control performance. 相似文献
999.
Studies on lactobionic acid introduced as a synergist in the presence of phosphonobutane-1,2,4-tricarboxylic acid(PBTC) and zinc ions for corrosion control of carbon steel in aqueous environment are presented.The investigations revealed that lactobionic acid(LBA) acts as an excellent synergist in corrosion inhibition.Optimum concentrations of all the three components of the ternary formulation are established by gravimetric studies.Potentiodynamic polarization studies indicate that the new ternary system is a mixed inhibitor.Impedance studies show that a protective film is formed on the metal surface in the presence of the inhibitor formulation.The film is found to exhibit its protective nature even at higher temperatures up to 60 °C.Analysis of the protective film by X-ray photoelectron spectroscopy(XPS) and reflection absorption Fourier transform infrared(FTIR) spectroscopy infers the presence of Zn(OH)_2,oxides and hydroxides of iron and the inhibitor molecules in the surface film probably in the form of a complex,[Zn(ll)—PBTC—LBA].The morphological studies by scanning electron microscopy(SEM) and the topographical studies by atomic force microscopy(AFM) also indicate the presence of protective film on the metal surface.A plausible mechanism of corrosion inhibition is proposed. 相似文献
1000.
S. Sumi P. Prabhakar Rao Peter Koshy 《Journal of Materials Science: Materials in Electronics》2014,25(7):2985-2991
The effect of simultaneous substitution of Mn in both A and B sites of the pyrochlore type semiconducting oxides: (CaCe1?2x Mn2x )(Sn1?x Mn x Nb)O7?δ (x = 0, 0.1, 0.2, 0.3 and 0.4) was studied by employing powder X-ray diffraction, Raman spectroscopy, scanning electron microscopy and electrical conductivity measurements. Besides the structural confirmation, Raman spectroscopy studies revealed the increased local disordering in the structure with progressive Mn substitution which is not observable in X-ray diffraction studies. The conductivity measurements confirm the negative temperature coefficient (NTC) behavior of the samples. Grain boundary dominant electrical characteristics have been observed in compounds with higher Mn concentration. Thermistor constant of the system lies in the range 6,700–8,500 K and the sensitivity values are in the range ?1 to ?2 %. The double substitution of Mn in this system offers to tune the NTC thermistor properties with increased localization of electrons in the lattice. 相似文献