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91.
Freeha Hafeez Ameer Fawad Zahoor Azhar Rasul Asim Mansha Razia Noreen Zohaib Raza Kulsoom Ghulam Ali Ali Irfan Gamal A. El-Hiti 《Molecules (Basel, Switzerland)》2022,27(15)
Piperazine-based dithiocarbamates serve as important scaffolds for numerous pharmacologically active drugs. The current study investigates the design and synthesis of a series of dithiocarbamates with a piperazine unit as well as their biological activities. Under ultrasound conditions, the corresponding piperazine-1-carbodithioates 5a–5j were synthesized from monosubstituted piperazine 2 and N-phenylacetamides 4a–4j in the presence of sodium acetate and carbon disulfide in methanol. The structures of the newly synthesized piperazines were confirmed, and their anti-lung carcinoma effects were evaluated. A cytotoxic assay was performed to assess the hemolytic and thrombolytic potential of the synthesized piperazines 5a–5j. The types of substituents on the aryl ring were found to affect the anticancer activity of piperazines 5a–5j. Piperazines containing 2-chlorophenyl (5b; cell viability = 25.11 ± 2.49) and 2,4-dimethylphenyl (5i; cell viability = 25.31 ± 3.62) moieties demonstrated the most potent antiproliferative activity. On the other hand, piperazines containing 3,4-dichlorophenyl (5d; 0.1%) and 3,4-dimethylphenyl (5j; 0.1%) rings demonstrated the least cytotoxicity. The piperazine with the 2,5-dimethoxyphenyl moiety (5h; 60.2%) showed the best thrombolytic effect. To determine the mode of binding, in silico modeling of the most potent piperazine (i.e., 5b) was performed, and the results were in accordance with those of antiproliferation. It exhibits a similar binding affinity to PQ10 and an efficient conformational alignment with the lipophilic site of PDE10A conserved for PQ10A. 相似文献
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93.
Munir Iqra Zahoor Ameer Fawad Rasool Nasir Naqvi Syed Ali Raza Zia Khalid Mahmood Ahmad Raheel 《Molecular diversity》2019,23(1):215-259
Chan–Lam coupling is one of the most popular and easy methods to perform arylation of amines (N-arylations). This cross-coupling is generally performed by reacting aryl boronate derivatives with a variety of substrates involving nitrogen containing functional groups such as amines, amides, ureas, hydrazine, carbamates. This article summarizes the synthetic applications of this reaction and the efforts of scientists to develop novel and efficient methodologies for this reaction.
相似文献94.
Nonlinear Dynamics - This paper presents the tracking behavior of fractional-order (FO) variants of the normalized least mean square (NLMS) algorithm in a nonstationary environment modeled as... 相似文献
95.
Ring opening of epoxides has been an area of interest for organic chemists, owing to their reactivity toward nucleophiles. Such reactions yield important products depending on the type of nucleophiles used. This review article covers the synthetic approaches (1991–2015) used for the ring opening of epoxides via carbon nucleophiles. 相似文献
96.
Nausheen Nazir Muhammad Zahoor Riaz Ullah Essan Ezzeldin Gamal A. E. Mostafa 《Molecules (Basel, Switzerland)》2021,26(1)
In this study, catechin (CTN) isolated from Elaeagnus umbellata was evaluated for in vitro antioxidant potential and inhibition of carbohydrate digestive enzymes (α-amylase and α-glucosidase). The compound was also tested for its in vivo antidiabetic potential using Sprague-Dawley rats as experimental animals. The effects of various doses of catechin in STZ (Streptozotocin) induced diabetic rats on fasting blood glucose level, body weight, lipid parameters, hepatic enzymes, and renal functions were evaluated using the reported protocols. The CTN exhibited the highest percent antioxidant for free radical scavenging activity against DPPH and ABTS free radicals, and inhibited the activity of carbohydrate digestive enzymes (with percent inhibition values: 79 ± 1.5% α-amylase and 80 ± 1.1% α-glucosidase). Administration CTN and standard glibenclamide significantly decreased the fasting blood glucose level and increased the body weight in STZ-induced diabetic rats. CTN significantly decreased the different lipid parameters, hepatic, and renal function enzyme levels along with Hb1c level in diabetic rats, while significantly increasing the high-density lipoprotein (HDL) level with values comparable to the standard glibenclamide. Further, the altered levels of glutathione and lipid peroxides of liver and kidney tissues were restored (by CTN) to levels similar to the control group. CTN significantly increased the antioxidant enzyme activities, total content of reduced glutathione, and reduced the malondialdehyde (MDA) level in rat liver and kidney tissues homogenates, and also corrected the histopathological abnormalities, suggesting its antioxidant potential. 相似文献
97.
Zahoor H. Farooqi Robina Begum Khalida Naseem Uma Rubab Muhammad Usman Abbas Khan Aysha Ijaz 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(13):2600-2608
Copolymer microgels based on N-isopropylacrylamide (NIPAM) and methacrylic acid (MAA) have been synthesized by free radical emulsion polymerization using N,N-methylenebisacrylamide (BIS) as a cross-linker. Synthesized microgels were characterized by Fourier transform infrared spectroscopy (FTIR). Then silver nanoparticles were fabricated in the synthesized microgels by in-situ reduction of AgNO3 with NaBH4. The formation of silver nanoparticles was confirmed by UV–Vis spectroscopy. The pH sensitivity of the copolymer microgels was investigated using dynamic light scattering technique (DLS). Hydrodynamic radius of P (NIPAM–MAA) microgels increases with increase in pH of the medium at 25°C. Surface plasmon resonance wavelength (λSPR) of silver nanoparticles increases with increase in hydrodynamic radius due to change in pH of the medium. The catalytic activity for the reduction of nitrobenzene (NB), an environmental pollutant, into aniline was investigated by UV–Vis spectroscopy in excess of NaBH4 using hybrid microgels as catalyst. The value of apparent rate constant (kapp) of the reaction was calculated using pseudo first order kinetic model and it was found to be linearly related to the amount of catalyst. The results were compared with literature data. The system was found to be an effective catalyst for conversion of NB into aniline. 相似文献
98.
Siddiqui IN Ahmad VU Zahoor A Ahmed A Khan SS Khan A Hassan Z 《Natural product communications》2010,5(11):1787-1788
Two new diarylheptanoids, trivially named nitidone A and nitidone B, have been isolated from Alnus nitida. The structure elucidation of the compounds was based primarily on 2D-NMR spectroscopic techniques and by comparison with literature data. 相似文献
99.
N-(4-chloro-3-aminobenzal)N′(4-aminophenyl)thiourea having phenylthiourea and azomethine groups was synthesized and exploited as starting material for the fabrication of new polymers. Novel diamine was condensed with pyromellitic dianhydride, 3,3′,4,4′-benzophenone-tetrcarboxylic dianhydride and 4,4′-(hexafluoroisopropylidene) diphthalic dianhydride to obtain poly(phenylthiourea azomethine imide)s. The structural explication of monomers and poly(phenylthiourea azomethine imide)s were carried out by FTIR, 1H and 13C NMR techniques along with crystallinity, organosolubility, inherent viscosity and molecular weight measurements. Accordingly, polymers bearing CS and -CN- moieties in the backbone demonstrated an amorphous nature and were readily soluble in amide solvents such as DMAc, DMF, and DMSO. Poly(phenylthiourea azomethine imide)s encompassed ηinh of 1.40-1.55 dL/g and were obtained in quantitative yields. In addition, GPC measurements of polymers revealed Mw around 60,291-67,665. Thermal stability of these polymers was ascertained via 10% weight loss temperatures around 514-533 °C in an inert atmosphere. Besides, glass transition temperatures of polyimides were found to be 272-276 °C. 相似文献
100.
Sonia Zulfiqar Zahoor Ahmad Muhammad Ilyas Sarwar 《Colloid and polymer science》2007,285(15):1749-1754
Soluble aromatic polyamide chains were prepared by reacting 4–4′-oxydianiline with isophthaloyl chloride in dimethylacetamide.
To quench the HCl produced during the polymerization reaction, a stoichiometric amount of triethylamine was added. The precipitates
formed were separated leaving behind clear polyamide resin. Thin and transparent film was obtained by evaporating the solvent
and was subjected for Fourier transform infrared (IR), nuclear magnetic resonance (NMR), gel permeation chromatography, thermogravimetric
analysis, differential scanning calorimetry, water absorption, and mechanical analyses. The transparent film was found to
be soluble in dimethylacetamide, dimethyl sulfoxide, and dimethylformamide. IR and NMR spectroscopic analyses confirmed the
structure of the polyamide while the gel permeation chromatography revealed the formation of a high-molecular-weight polymer.
Thermogravimetry, differential scanning calorimetry, water absorption, and mechanical testing were also performed to further
verify its physical properties. A soluble aromatic polyamide was successfully synthesized by solution polymerization and characterized.
The polyamide has film-forming property, and the film is transparent, mechanically strong, and thermally stable. 相似文献