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1.
Farukh Arjmand Shamima Parveen Mala Chauhan Shaiba Parveen Sartaj Tabassum 《Transition Metal Chemistry》2006,31(2):237-245
New mononuclear and dinuclear complexes [3-hydroxyethyl-1,3,5,8,11pentaazacyclotridecane]copper(II) (1)/nickel(II) (2) perchlorate and O,O ethane bridged bis-copper(II) (3)/nickel(II) (4) macrocycles have been synthesized and characterized by various spectroscopic techniques, viz. i.r., n.m.r., e.p.r., u.v.–vis. and conductance measurements. Spectral data and conductance measurements reveal that all
the complexes are consistent with square-planar geometry and are ionic in nature. The catalytic activity of the dinuclear
Cu(II) complex (3) in the presence of pyrocatechol was determined spectrometrically by monitoring the increase of the o-benzoquinone characteristic absorption band at 25,000 cm−1 with respect to time in DMF saturated with molecular oxygen. The kinetic parameters Vmax (2.8×10−3 M s−1) and KM (1.4×10−3 mm) have been determined by Michaelis–Menten method. Electrochemistry of the dinuclear Cu(II) complex has been studied in the
presence of molecular oxygen with pyrocatechol and without pyrocatechol at a scan rate of 0.1 V s−1 by cyclic voltammetry. On addition of pyrocatechol, complex shows a shift in Epc, Epa and E1/2 values indicating the oxidation of substrate (pyrocatechol). 相似文献
2.
New asymmetric ligands have been synthesized by condensing o-phenylene diamine with CS2 and PhCHO/MeCHO, and their complexes with MnII, CoII, NiII, CuII and ZnII were prepared and characterized by elemental analyses, conductivity measurements, i.r., u.v.–vis., e.p.r. and n.m.r. spectra. The transition metals in the complexes show square planar geometry and are ionic. Photokinetic studies of the DNA-metal complexes [C10H10S4N2Cu](NO3)2 and [C10H10S4N2Ni](NO3)2 were carried out and the rate constants k(DNA-complex) were calculated. The results indicate that DNA reacts with the metal complex in two steps. DNA first undergoes structural degradation and is then completely hydrolysed as indicated by spectral changes consistent with earlier results. The asymmetric N2S2 macrocyclic metal complexes show a strong propensity for DNA inhibition and can be used as an intercalating binding model. 相似文献
3.
Hafiz Rameez Khalid Muhammad Aamir Sana Tabassum Youssef Saeed Alghamdi Ahmad Alzamami Usman Ali Ashfaq 《Molecules (Basel, Switzerland)》2022,27(19)
Hepatocellular carcinoma (HCC) is one of the most common malignant liver tumors with high mortality. Chronic hepatitis B and C viruses, aflatoxins, and alcohol are among the most common causes of hepatocellular carcinoma. The limited reported data and multiple spectra of pathophysiological mechanisms of HCC make it a challenging task and a serious economic burden in health care management. Solanum surattense (S. surattense) is the herbal plant used in many regions of Asia to treat many disorders including various types of cancer. Previous in vitro studies revealed the medicinal importance of S. surattense against hepatocellular carcinoma. However, the exact molecular mechanism of S. surattense against HCC still remains unclear. In vitro and in silico experiments were performed to find the molecular mechanism of S. surattense against HCC. In this study, the network pharmacology approach was used, through which multi-targeted mechanisms of S. surattense were explored against HCC. Active ingredients and potential targets of S. surattense found in HCC were figured out. Furthermore, the molecular docking technique was employed for the validation of the successful activity of bioactive constituents against potential genes of HCC. The present study investigated the active “constituent–target–pathway” networks and determined the tumor necrosis factor (TNF), epidermal growth factor receptor (EGFR), mammalian target of rapamycin (mTOR), Bcl-2-like protein 1(BCL2L1), estrogen receptor (ER), GTPase HRas, hypoxia-inducible factor 1-alpha (HIF1-α), Harvey Rat sarcoma virus, also known as transforming protein p21 (HRAS), and AKT Serine/Threonine Kinase 1 (AKT1), and found that the genes were influenced by active ingredients of S. surattense. In vitro analysis was also performed to check the anti-cancerous activity of S. surattense on human liver cells. The result showed that S. surattense appeared to act on HCC via modulating different molecular functions, many biological processes, and potential targets implicated in 11 different pathways. Furthermore, molecular docking was employed to validate the successful activity of the active compounds against potential targets. The results showed that quercetin was successfully docked to inhibit the potential targets of HCC. This study indicates that active constituents of S. surattense and their therapeutic targets are responsible for their pharmacological activities and possible molecular mechanisms for treating HCC. Lastly, it is concluded that active compounds of S. surattense act on potential genes along with their influencing pathways to give a network analysis in system pharmacology, which has a vital role in the development and utilization of drugs. The current study lays a framework for further experimental research and widens the clinical usage of S. surattense. 相似文献
4.
Tabassum Jannat Md. Jamal Hossain Ahmed M. El-Shehawi Md. Ruhul Kuddus Mohammad A. Rashid Sarah Albogami Ibrahim Jafri Mohamed El-Shazly Mohammad Rashedul Haque 《Molecules (Basel, Switzerland)》2022,27(13)
The aim of the study was to conduct phytochemical and pharmacological investigations of Wrightia coccinea (Roxb. ex Hornem.) Sims via several in vitro, in vivo, and in silico models. A total of four compounds were identified and isolated from the methanol extract of the bark and the methanol extract of the seed pulp of W. coccinea through successive chromatographic techniques and were characterized as 3β-acetyloxy-olean-12-en-28-ol (1), wrightiadione (2), 22β-hydroxylupeol (3), and β-sitosterol (4) by spectroscopic analysis. The aqueous fraction of the bark and chloroform fraction of the fruits provided the most potent antioxidant capacity (IC50 = 7.22 and 4.5 µg/mL, respectively) in DPPH free radical scavenging assay compared with the standard ascorbic acid (IC50 = 17.45 µg/mL). The methanol bark extract and the methanol fruit coat extract exerted anti-diarrheal activity by inhibiting 74.55 ± 0.67% and 77.78 ± 1.5% (mean ± SEM) of the diarrheal episode in mice, respectively, after four hours of loading the samples. In the hypoglycemic test, the methanol bark extract and the methanol fruit coat extract (400 mg/kg) produced a significant (p < 0.05) reduction in the blood glucose level in mice. Both doses of the plant extracts (200 mg/kg and 400 mg/kg) used in the study induced a significant (p < 0.05) increase in pain reaction time. The in vitro and in vivo findings were supported by the computational studies. The isolated compounds exhibited higher binding affinity compared with the standard drugs towards the active binding sites of glutathione reductase, epidermal growth factor receptor (EGFR), kappa opioid receptor, glucose transporter 3 (GLUT 3), Mu opioid receptor, and cyclooxygenase 2 (COX-2) proteins due to their potent antioxidant, cytotoxic, anti-diarrheal, hypoglycemic, and central and peripheral analgesic properties, respectively. The current findings concluded that W. coccinea might be a potential natural source for managing oxidative stress, diarrhea, hyperglycemia, and pain. Further studies are warranted for extensively phytochemical screening and establishing exact mechanisms of action. 相似文献
5.
Hasan M. Khan Shagufta Naz Safia Tabassum 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(1):225-229
Aqueous solution of crystal violet has been evaluated spectrophotometrically as a gamma-ray chemical dosimeter. The response
of the chemical dosimetric system has also been investigated under different environmental conditions, such as light and temperature.
In the present study the response has been measured at two wavelengths; 588 nm (λmax of the irradiated solution) and 500 nm. The response of the crystal violet dosimeter was linear in the dose range of 50–550 Gy
at pH 5.6 when absorption measurements were made at 588 and 500 nm. The response of the crystal violet dosimeter during post-irradiation
storage at room temperature in dark showed slight decrease in absorbance at 588 and 510 nm but the response was almost stable
at 460 nm. For higher doses, the change in the response was greater as compared to the low doses. Post-irradiation stability
during diffused sunlight showed significant decrease in the response for higher dose at 588 and 510 nm and slower decrease
in the response for lower dose at the above mentioned wavelengths. However the response was almost stable up to 97 days at
460 nm for higher and lower doses. At 4 °C, the decrease in the absorbance was slower at 588 and 510 nm while the response
was almost constant at 460 nm. At higher temperatures, such as 40 °C, the decrease in the absorbance was greater at 588 and
510 nm while at 460 nm the absorbance was almost constant for about 3 months. 相似文献
6.
Santhosh Govindaraju Sumaiya Tabassum 《Phosphorus, sulfur, and silicon and the related elements》2017,192(3):292-299
Silica iodide catalyzed, competent synthesis of 15 novel substituted-1,4,5,6-tetrahydropyridine-3-carboxylate derivatives was achieved by a one-pot four-component cyclocondensation of Meldrum's acid, aryl aldehydes, aromatic amines and ethyl acetoacetate under ultrasonic irradiation. In comparison to the conventional methods, our protocol is convenient, eco-friendly and offers several benefits such as: mild conditions, high yields, shorter reaction time and ease in product isolation. 相似文献
7.
A new template-directed chiral porphyrin [(TPP)Co(Trp)], where TPP = tetraphenylporphyrin and Trp = 1-tryptophan, was prepared and characterized by various physico-chemical methods. Interaction of [(TPP)Co(Trp)] with calf thymus DNA was studied by u.v.–vis. spectroscopy and cyclic voltammetry. The complex [(TPP)Co(Trp)], after interaction with calf thymus DNA, shows a shift in the absorption spectrum and a large hypochromicity, indicating an intercalating binding mode. This observation was further confirmed by the electrochemical behavior of [(TPP)Co(Trp)] before and after interaction with calf thymus DNA. The complex experiences a negative shift in E
1/2 and a decrease in E
p. The ratio of cathodic to anodic peak currents i
pc/i
pa was 1 for [(TPP)Co(Trp)] while for DNA bound complex i
pc/i
pa 1, suggesting that the calf thymus DNA moiety is bound strongly to the complex [(TPP)Co(Trp)]. Kinetic studies of the DNA-porphyrin complex reveal a psuedo-first order rate law as the plot of k
obs
versus calf thymus DNA is linear passing through the origin. 相似文献
8.
Fatima Javed Saqib Ali Saira Shahzadi Nasir Khalid Saira Tabassum Imran Khan Saroj K. Sharma Kushal Qanungo 《中国化学会会志》2015,62(8):728-738
New organotin(IV) complexes have been synthesized by treating potassium o‐isopropyl carbonodithioate with R2SnCl2/R3SnCl in 1 : 2/1 : 1 M/L ratio. All complexes have been characterized by IR and NMR (1H, 13C) spectroscopy. IR results shows that ligand acts as bidentate which is also confirmed by semi‐empirical study. NMR data reveals four coordinated geometry in solution. Computed positive heat of formation shows that complex 5 is thermodynamically unstable. UV/visible spectroscopy was used to assess the mode of interaction and binding of the complexes with DNA which shows that complex 5 exhibits higher binding constant as compared to complex 3 . In protein kinase inhibition assay, compound 3 was found most active, while other biological activities shows that triorganotin(IV) complexes are biologically more active as compared to diorganotin(IV) complexes. 相似文献
9.
Facile LC‐UV methods for simultaneous monitoring of ciprofloxacin and rosuvastatin in API,formulations and human serum 下载免费PDF全文
An efficient, selective and cost‐effective liquid chromatographic assay was developed and validated for the simultaneous quantification of ciprofloxacin and rosuvastatin in Active Pharmaceutical Ingredients (API), pharmaceutical formulations and in human serum. The chromatographic system consisted of mobile phase methanol–water, 90:10 v/v at pH 3.0 adjusted with o‐phosphoric acid, pumped at 1.0 mL/min through a prepacked Purospher Star C18 (5 µm, 25 × 0.46 cm) column and effluent was monitored at the isosbestic point (255 nm) as well as at the λmax of individual drugs (243 and 271 nm). The method was validated over a linear concentration range of 0.25–15 µg/mL for ciprofloxacin and 0.33–20 µg/mL for rosuvastatin (r2 ≥ 0.999). The ranges of reliable response (limits of detection and quantitation) for ciprofloxacin were 3–15 and 9–45 ng/mL and 17–29 and 52–88 ng/mL, respectively, for rosuvastatin in all API, pharmaceutical formulations and human serum. Analytical recovery from human serum was >98% and relative standard deviation (RSD) was <2. The accuracies were 97.13–102.55 and 97.41–101.31% and precisions in RSD were 0.04–1.90 and 0.02–1.23% for ciprofloxacin and rosuvastatin, respectively. No matrix interferences, ion suppression/enhancement and carry‐over were detected. The total assay run time was less than 5 min. In another study, for optimum performance the detector was programmed for multiwavelength scanning at the absorption maxima of each component. Consequently, the linearity range was improved and limit of detection and quantitation values were down to 1–4 and 4–12 ng/mL for ciprofloxacin and 3–5 and 9–15 ng/mL for rosuvastatin, respectively. The validation parameters fitted ICH guidelines through the isosbestic and individual λmax approach. The small sample volume and simplicity of preparation make this method suitable for use in human serum samples, pharmaceutical formulations, quality control, drug–drug interaction studies, clinical laboratories, drug research centers and forensic medical centers. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
10.
Structural Chemistry - The N-methyl-D-aspartate (NMDA) is the family of glutamate receptor, which is involved in controlling synaptic plasticity and memory function; but overactivation of this... 相似文献