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61.
62.
Cobalt (II), copper (II), nickel (II) and zinc (II) complexes with 2-hydroxy-1-naphthaldehyde derived N-substituted sulfonamides have been synthesized and the nature of bonding and structure of compounds have been deduced from physical, analytical and spectral (IR, (1)H NMR, (13)C NMR, Mass and electronic) data. An octahedral geometry has been suggested for the complexes. Complexes along with the ligands were assessed for their antibacterial and antifungal activities on different species of pathogenic bacteria and fungi. The results revealed the ligands to possess moderate to significant antibacterial activity which was, in many cases, enhanced on chelation. Similar results were observed for antifungal activity. Brine shrimp bioassay was also carried out for in vitro cytotoxic properties against Artemia salina. 相似文献
63.
Zahid M Gaikwad NW Ali MF Lu F Saeed M Yang L Rogan EG Cavalieri EL 《Free radical biology & medicine》2008,45(2):136-145
Resveratrol (Resv), a natural occurring phytolexin present in grapes and other foods, possesses chemopreventive effects revealed by its striking modulation of diverse cellular events associated with tumor initiation, promotion, and progression. Catechol estrogens generated in the metabolism of estrogens are oxidized to catechol quinones that react with DNA to form predominantly depurinating estrogen-DNA adducts. This event can generate the mutations responsible for cancer initiation. In this regard, Resv acts as both an antioxidant and an inducer of the phase II enzyme NAD(P)H:quinone oxidoreductase 1 (NQO1). In this report, we present the effects of Resv on the metabolism of estrogens in normal breast epithelial cells (MCF-10F) treated with 4-hydroxyestradiol (4-OHE(2)) or estradiol-3,4-quinone (E(2)-3,4-Q). Resv induced NQO1 in a dose- and time-dependent manner, but did not affect the expression of catechol-O-methyltransferase. Ultraperformance liquid chromatography/tandem mass spectrometry was used to determine the effects of Resv on estrogen metabolism. Preincubation of the cells with Resv for 48 h decreased the formation of depurinating estrogen-DNA adducts from 4-OHE(2) or E(2)-3,4-Q and increased formation of methoxycatechol estrogens. When Resv was also present with the 4-OHE(2) or E(2)-3,4-Q, even greater increases in methoxycatechol estrogens were observed, and the DNA adducts were undetectable. We conclude that Resv can protect breast cells from carcinogenic estrogen metabolites, suggesting that it could be used in breast cancer prevention. 相似文献
64.
Ikram-ul-Haq Zhao Chang-Xing Zahid Mukhtar Cheruth Abdul Jaleel Mohamed Mahgoub Azooz 《Journal of plant physiology》2009,166(14):1568-1575
This experiment assessed the effect of partial physical desiccation on plant regeneration efficiency in scutellum-derived embryogenic calluses of rice (Oryza sativa L.) variety Super basmati. A number of callusing cultures were developed, and efficient callus induction was observed on MS (Murashige and Skoog) basal medium supplemented with 2.0 mg/L 2,4-dichlorophenoxy acetic acid. The calluses were proliferated on the same medium for 3 weeks and then shifted to dehydration desiccation treatment for 72 h. The desiccated calluses were cultured on different media for somatic embryogenesis and plant regeneration. A medium with 2.0 mg/L α-napthaleneacetic acid, 10.0 mg/L abscisic acid , 2.0 mg/L kinetin was best for somatic embryogenesis only, but not for further plant development. After 10 d, differentiated calluses were sub-cultured on medium with various concentrations and types of carbohydrates (carbon source) in 1MS2j medium. A large number of plantlets (14.51±2.81 and 8.56±2.90 plants/callus) were regenerated via chemical desiccation, on MS with 3% maltose+3% sorbitol and 6% sucrose, respectively. Under dehydration on only simple MS (3% sucrose), 11.23±3.22 plants/callus were developed. Under conditions of dehydration and chemical desiccation, plant regeneration rates were higher than the calluses cultured on simple MS medium in the presence of plant growth regulator. After somatic embryogenesis, >25% plants were sterile. The protocol used here may allow maximum regeneration of normal and fertile plantlets of super basmati rice within 3 months. 相似文献
65.
Khalid M. Khan Sumayya Saeed Muhammad Ali Madiha Gohar Javariya Zahid Ambreen Khan Shahnaz Perveen M. Iqbal Choudhary 《Bioorganic & medicinal chemistry》2009,17(6):2447-2451
A series of unsymmetrically disubstituted urea derivatives 1–28 has been synthesized and screened for their antiglycation activity in vitro. Compounds 26 (IC50 = 4.26 ± 0.25 μM), 1 (IC50 = 5.8 ± 0.08 μM), 22 (IC50 = 4.26 ± 0.25 μM), 6 (IC50 = 6.4 ± 0.02 μM), 5 (IC50 = 6.6 ± 0.26 μM), 2 (IC50 = 7.02 ± 0.31 μM), 3 (IC50 = 7.14 ± 0.84 μM), 27 (IC50 = 7.27 ± 0.36 μM), 4 (IC50 = 8.16 ± 1.04 μM), 21 (IC50 = 8.4 ± 0.15 μM), 23 (IC50 = 9.0 ± 0.35 μM) and 13 (IC50 = 15.22 ± 6.7 μM) showed an excellent antiglycation activity far better than the standard (rutin, IC50 = 41.9 ± 2.3 μM). This study thus provides a series of potential molecules for further studies of antiglycation agents. 相似文献
66.
Hadda TB Akkurt M Baba MF Daoudi M Bennani B Kerbal A Chohan ZH 《Journal of enzyme inhibition and medicinal chemistry》2009,24(2):457-463
A series of nine polypyridyl-ruthenium (II) complexes (N-ligands = 2,2'-bipyridines; 2,2'-6',2'-terpyridines, di-alkyloxy-2,2'-6,2-bipyridine-3,3'-di-carboxylates), were tested against Mycobacterium tuberculosis (MBT). The complex (11) showed remarkable activity against MBT as compared to other complexes, (1-10). The aquo ligand of complex (11), as opposed to other chloro and acetonitrile derivatives, appears to play a key role in the antitubercular potency of this new class of metal-based compounds. 相似文献
67.
Iqbal Ahmad Kiran Qadeer Saima Zahid Muhammad Ali Sheraz Tehmina Ismail Waqar Hussain Izhar Ahmad Ansari 《AAPS PharmSciTech》2014,15(5):1324-1333
The degradation kinetics of 5 × 10−5 M cyanocobalamin (B12) and hydroxocobalamin (B12b) in the presence of ascorbic acid (AH2) was studied in the pH range of 1.0–8.0. B12 is degraded to B12b which undergoes oxidation to corrin ring cleavage products. B12b alone is directly oxidized to the ring cleavage products. B12 and B12b in degraded solutions were simultaneously assayed by a two-component spectrometric method at 525 and 550 nm without interference from AH2. Both degrade by first-order kinetics and the values of the rate constants at pH 1.0–8.0 range from 0.08 to 1.05 × 10−5 s−1 and 0.22–7.62 × 10−5 s−1, respectively, in the presence of 0.25 × 10−3 M AH2. The t1/2 values of B12 and B12b range from 13.7 to 137.5 h and 2.5–87.5 h, respectively. The second-order rate constants for the interaction of AH2 with B12 and B12b are 0.05–0.28 × 10−2 and 1.10–30.08 × 10−2 M−1 s−1, respectively, indicating a greater effect of AH2 on B12b compared to that of B12. The kobs–pH profiles for both B12 and B12b show the highest rates of degradation around pH 5. The degradation of B12 and B12b by AH2 is affected by the catalytic effect of phosphate ions on the oxidation of AH2 in the pH range 6.0–8.0.KEY WORDS: ascorbic acid, cyanocobalamin, degradation, hydroxocobalamin, kinetics, two-component spectrometry 相似文献
68.
The present study was conducted with the aim to investigate the immuno-modulatory and histological stabilization effects of nanocarrier–based transcutaneous co-delivery of hydrocortisone (HC) and hydroxytyrosol (HT). In this investigation, the clinical and pharmacological efficacies of nanoparticle (NP)-based formulation to alleviate 2,4-dinitrofluorobenzene (DNFB)-induced atopic dermatitis (AD) was explored by using an NC/Nga mouse model. Ex vivo visual examination of AD induction in experimental mice indicated remarkable control of NP-based formulations in reducing pathological severity of AD-like skin lesions. Therapeutic effectiveness of NP-based formulations was also evaluated by comparing skin thickness of AD-induced NP-treated mice (456±27 µm) with that of atopic mice (916±37 µm). Analysis of the immuno-spectrum of AD also revealed the dominance of NP-based formulations in restraining immunoglobulin-E (IgE), histamine, prostaglandin-E2 (PGE2), vascular endothelial growth factor-α (VEGF-α), and T-helper cells (TH1/TH2) producing cytokines in serum and skin biopsies of tested mice. These anti-AD data were further supported by histological findings that revealed alleviated pathological features, including collagen fiber deposition, fibroblasts infiltration, and fragmentation of elastic fibers in experimental mice. Thus, NP-mediated transcutaneous co-delivery of HC and HT can be considered as a promising therapy for managing immunological and histological spectra associated with AD. 相似文献
69.
Zahid H. Chohan Humayun Pervez Khalid Mohammed Khan A. Rauf 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):51-56
A method is described for the preparation of novel cephalexin-derived furanyl-, thiophenyl-, pyrrolyl-, salicylyl- and pyridyl-containing compounds showing potent antibacterial activity. The binding of these newly synthesized antibacterial agents with metal ions such as cobalt(II), copper(II), nickel(II) and zinc(II) has been studied and their inhibitory properties against various bacterial species such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae are also reported. These results suggest that metal ions to possess an important role in the designing of metal-based antibacterials and that such complexes are more effective against infectious diseases compared to the uncomplexed drugs. 相似文献
70.
Sandeep Rana Yogesh A. Sonawane Margaret A. Taylor Smitha Kizhake Muhammad Zahid Amarnath Natarajan 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3736-3740
We synthesized a library of aminopyrazole analogs to systematically explore the hydrophobic pocket adjacent to the hinge region and the solvent exposed region of cyclin dependent kinases. Structure-activity relationship studies identified an optimal substitution for the hydrophobic pocket and analog 24 as a potent and selective CDK2/5 inhibitor. 相似文献