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61.
62.
Due to an increasing demand for effective anti-cancer drugs, an oxopyrrolidine-based ligand, sodium 1-(3-(2-aminoethylamino)propyl)-5-oxopyrrolidine-2-carboxylate, was synthesised by the sodium hydride-assisted coupling of pyroglutamic acid with 1,3-diiodopropane under a nitrogen atmosphere. The intermediate thus formed was allowed to react with ethylenediamine in acetonitrile. The ligand formed individual complexes with Cu(II) and Ni(II) metal ions, respectively. The complexes were relatively resistant to degradation in PBS at physiological pH. The DNA-binding constants (K b) for the ligand, copper and nickel complexes were 2.09 × 104 M-1, 2.37 × 104 M-1 and 2.11 × 104 M-1, respectively, revealing the strong binding of these complexes with DNA. Haemolysis assays indicated that the ligand and its complexes were less toxic to rabbit RBCs than doxorubicin. Lipinski’s parameters calculated for the reported compounds indicated their good oral bioavailability. All the compounds exhibited good activities towards MCF-7 (wild type) cancer cell lines. The results of in silico studies, DNA-binding and anti-cancer activities indicated that the reported compounds might be interacting with DNA as one of their possible mechanisms of action. 相似文献
63.
Alali FQ Tawaha K El-Elimat T Qasaymeh R Li C Burgess J Nakanishi Y Kroll DJ Wani MC Oberlies NH 《Natural product research》2006,20(6):558-566
As a part of our continuing investigation of Jordanian Colchicum species, the biologically active components of Colchicum hierosolymitanum Feinbr and Colchicum tunicatum Feinbr (Colchicaceae) were pursued. The brine shrimp lethality test (BSLT) was used to direct the fractionation and isolation of active components. Five and four known colchicinoids were isolated and characterized from C. tunicatum and C. hierosolymitanum, respectively. The known colchicinoids, reported for the first time from these two species are: (-)-colchicine (I), 3-demethyl-(-)-colchicine (II), (-)-cornigerine (III), beta-lumicolchicine (IV), and (-)-androbiphenyline (V) from C. tunicatum, and (-)-colchicine (I), 2-demethyl-(-)-colchicine (VI), (-)-cornigerine (III), and beta-lumicolchicine (IV) from C. hierosolymitanum. The chemical structures of the isolated compounds have been elucidated using a series of spectroscopic and spectrometric techniques principally; 1D-NMR (1H and 13C) and low resolution EI-MS and APCIMS. All pure compounds were evaluated for cytotoxicity against three human cancer cell lines; MCF-7 human breast carcinoma, NCI-H460 human large cell lung carcinoma, and SF-268 human astrocytoma. (-)-Colchicine (I) and (-)-cornigerine (III) were found to be the most bioactive of the identified compounds with EC50 values in the range of 0.016-0.097 microM. 相似文献
64.
This work reveals an exploration of self-focusing of Hermite-cosine-Gaussian laser beam in a collisionless plasma under relativistic nonlinearity. Self-focusing along with self-trapping of Hermite-cosine-Gaussian laser beam are analyzed for different values of laser intensity, plasma density, and decentered parameters. Mathematical analysis displays that these parameters play a major role in achieving the stronger and earlier self-focusing. Further, a comparative study between self-focusing of Hermite-cosine-Gaussian laser beam with and without exponential density ramp profile is introduced. Plasma density transition with exponential profile is found to be more effective in order to have stronger self-focusing. The present analysis may lead to very useful applications in the field of efficient harmonic generation, laser driven fusion etc. 相似文献
65.
Mansukh C. Wani Harold L. Taylor James B. Thompson Monroe E. Wall Andrew T. McPhail Kay D. Onan 《Tetrahedron》1979,35(1):17-24
The structure of Undulatone, a new antileukaemic quassinoid from Hannoa undulata was determined by spectral means and confirmed by single crystal X-ray analysis of the methanol solvate. 相似文献
66.
Sumit S. Chourasiya Aabid A. Wani C.M. Nagaraja Asit K. Chakraborti Prasad V. Bharatam 《Tetrahedron》2018,74(27):3634-3641
The potentiality of the N-(acridin-9-yl)arenesulfonamide moiety as a hybrid pharmacophore due to the distinct pharmacological activities of acridines and aryl/heteroaryl sulfonamides prompts to synthesise N-(acridin-9-yl)arenesulfonamides and study their structural properties. Various N-(acridin-9-yl)arene/heteroarenesulfonamides were obtained through the development of a new methodology adopting the Pd2(dba)3-catalyzed CN bond formation strategy for the reaction of 9-chloloroacridine with arene/heteroarenesulfonamides. The 1H and 13C NMR spectra suggest these N-(acridin-9-yl)arene/heteroarenesulfonamides to exist solely as the sulfonimide tautomer rather than anticipated sulfonamide form and was confirmed by the single crystal XRD analysis of one of the newly synthesized compounds. The quantum chemical studies rationalized this tautomeric preference revealing that the sulfonimide tautomers are more stable than the sulfonamide tautomers by ?0.67 to ?5.12?kcal/mol in the gas phase. In the solid state, the sulfonimide tautomer is stabilized by intermolecular hydrogen bond between NH?OS and π? π stacking between the acridine rings. 相似文献
67.
4,4-Dimethyl-6-methoxy-4-sila-1-tetralone (2) was prepared by a modified literature procedure and converted to 3-methoxy-6,6-dimethyl-6-silaestra-1,3,5(10),8,14-pentaen-17β-yl acetate (5c). Catalytic hydrogenation of 5c gave 3-methoxy-6,6-dimethyl-6-silaestra-1,3,5(10),8-tetraen-17β-yl acetate (6b), and its 14-iso- and Δ1,3,5(10),8(14) isomers, the proportions varying with the catalyst and solvent. Reduction of 6b with lithium-liquid ammonia, and O-demethylation, gave 6,6-dimethyl-6-silaestradiol (8b). Reduction of the 3-methyl ether of 8b with lithium-liquid ammonia-t-butanol and hydrolysis afforded 3-keto-6,6-dimethyl-6-silaestr-1(10)-en-17β-ol (15), which was catalytically reduced to its 1,10α-dihydro derivative 17. The 5,6 SiC bond of 8b, 15 and their derivatives was cleaved by boron tribromide, aq. ethanolic hydrogen fluoride, and other reagents, providing a series of 5,6-seco-6,6-dimethyl-6-silasteroids. X-ray crystallographic analysis of 17 and the 17α-ethynyl derivative of 15 confirmed the stereochemical assignments. None of the compounds which were subjected to uterotropic, anti-uterotropic, or post-coital assays, showed significant activity. A partially completed synthesis of 6-silaestradiol (21a) is described. 相似文献
68.
El-Mahdy MA Zhu Q Wang QE Wani G Patnaik S Zhao Q Arafa el-S Barakat B Mir SN Wani AA 《Photochemistry and photobiology》2008,84(2):307-316
Many naturally occurring agents are believed to protect against UV-induced skin damage. In this study, we have investigated the effects of naringenin (NG), a naturally occurring citrus flavonone, on the removal of UVB-induced cyclobutane pyrimidine dimers (CPD) from the genome and apoptosis in immortalized p53-mutant human keratinocyte HaCaT cells. The colony-forming assay shows that treatment with NG significantly increases long-term cell survival after UVB irradiation. NG treatment also protects the cells from UVB-induced apoptosis, as indicated by the absence of the 180 base pair DNA ladders and the appearance of sub-G1 peak using agarose gel electrophoresis and flow cytometric analysis, respectively. The UVB-induced poly (ADP-ribose) polymerase-1 (PARP-1) cleavage, caspase activation and Bax/Bcl2 ratio were modulated following NG treatment, indicating an antiapoptotic effect of NG in UVB-damaged cells that occurs at least in part via caspase cascade pathway. Moreover, treatment of UVB-irradiated HaCaT cells with NG enhances the removal of CPD from the genome, as observed by both direct quantitation of CPD in genomic DNA and immuno-localization of the damage within the nuclei. The study provides a molecular basis for the action of NG as a promising natural flavonoid in preventing skin aging and carcinogenesis. 相似文献
69.
Ekar Satish U. Shekhar Ganga Khollam Yogesh B. Wani Poonam N. Jadkar Sandesh R. Naushad Mu Chaskar Manohar G. Jadhav Santosh S. Fadel Alaa Jadhav Vijaykumar V. Shendkar Janardhan H. Mane Rajaram S. 《Journal of Solid State Electrochemistry》2017,21(9):2713-2718
Journal of Solid State Electrochemistry - Nanorods (NRs) of TiO2 have biogenically been prepared, i.e., from the extract of Phellinus linteus mushroom. The presence of mixed anatase and... 相似文献
70.
The dislocation etchant has been established for single crystals of Mo1−xWxSe2 system. Effect of concentration of an etchant on the etch rate has been discussed. The morphology of etch pits is also described. The etch activation energies for all the compositions of these crystals for a particular concentration (7 N) of an etchant has been found out. The etch activation energies for a particular composition (x = 0.4) of crystals with different concentrations of an etchant have been investigated and the results have been discussed. 相似文献