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981.
S. Naveen S. Lakshmi Dinesh Manvar Alpesh Parecha Anamik Shah M. Anandalwar Sridhar J. Shashidhara Prasad 《Journal of chemical crystallography》2007,37(11):733-738
2-amino-3-ethoxycarbonyl-4-(4′-methoxy Phenyl)-4H-pyrano-[3,2-c]-chromene-6-methyl-5-one was synthesized by the two-component reaction of 6-methyl-4-hydroxy coumarin with 4′-methoxy-2-cyano cinnamate, which was synthesized by Knoevenagel reaction with 88% yield. The compound obtained was characterized by spectroscopic techniques and confirmed by X-ray crystallographic studies. The crystallographic data analysis reveals that the title compound crystallizes in the triclinic space group \(P\overline{1}\) with cell parameters a = 7.7750(8) Å, b = 9.0310(6) Å, c = 15.6120(17) Å, α = 77.249(7)°, β = 115.860(3)°, γ = 70.139(7)°, V = 1,003.0(16) Å3 for Z = 4. The structure has been solved by direct methods and refined to R1 = 0.0552 for 3,164 observed reflections with I > 2 σ(I). The pyran ring is in a flattened boat conformation. The carbonyl group is oriented in a -synperiplanar(cis) conformation.
相似文献
982.
The separate spin evolution quantum hydrodynamics(SSE-QHD) model is used to investigate the energy behavior for ion acoustic waves in degenerate quantum plasma. Numerical results show that the energy flow speed decreases with spin polarization parameter. It is also shown that it decreases with the increasing rate up to a certain range of wave number and then it goes to zero asymtotically. It is observed that Bohm potential suppresses the energy flow speed. It is also noticed that the energy flow speed deviates from the group velocity even in the absence of Bohm potential effect. However, the contribution of of Bohm poential effect in spin polarized plasma reduces the extent of deviation. 相似文献
983.
Gandhi Keval Shah Zalak Rai Ajay Kumar 《International Journal of Theoretical Physics》2020,59(4):1129-1156
International Journal of Theoretical Physics - We study the masses of radial and orbital excited states of nonstrange singly charmed baryons in the framework of hypercentral Constituent Quark Model... 相似文献
984.
Understanding the segmental dynamics of polymer chains is cardinal to decipher the microscopic behaviour in order to modulate the bulk properties of polymers. The study of electron spin resonance (ESR) spectroscopy of spin-labelled polymers is useful to understand the segmental dynamics of polymer chains in solution. In this paper, poly(acrylic acid)s (PAAs) were spin labelled with 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl radicals. Spin-labelled PAAs (SL-PAAs) were characterised by Fourier-transform infrared spectroscopy, ultraviolet–visible spectroscopy, thermogravimetric analysis, differential scanning calorimetry, cyclic voltammetry (CV), and ESR analyses. The polyelectrolyte complexes of SL-PAAs were prepared by employing poly(diallyldimethylammonium chloride) (PDADMAC) as the polycation and analysed by transmission electron microscopy, dynamic light scattering (DLS), and ESR spectroscopies. The effect of molar mass on the segmental dynamics of SL-PAAs in pristine as well as in the form of polyelectrolyte complexes (PECs) was studied. The results indicated that SL-PAAs show a differential complexation behaviour with PDADMAC in the PECs depending on their molar mass. 相似文献
985.
986.
Balu Alagar Venmathi Maran Mohammad Iqbal Prakash Gangadaran Byeong-Cheol Ahn Pasupuleti Visweswara Rao Muhammad Dawood Shah 《Molecules (Basel, Switzerland)》2022,27(5)
Hepatotoxicity is a major global public health concern. Despite advances in modern medicine, the demerits of chemically prepared drugs outweigh their merits. In addition, the treatment of liver diseases based on modern medical principles has been found to produce several undesired side effects. Therefore, the exploration of medicinal plants has gained worldwide attention for treating various diseases, including liver diseases, owing to their potential efficacy and cost effectiveness. Several plants, including Andrographis paniculata, Bauhinia purpurea, Commelina nudiflora, Dillenia suffruticosa, Elaeis guineensis, Lygodium microphyllum, and Nephrolepis biserrata, have been reported with hepatoprotection. Moreover, these plants have been shown to play a vital role in ameliorating cellular damage because they contain several phytochemicals, including alkaloids, saponins, flavonoids, tannins, terpenoids, steroids, polyphenols, and diterpenoid lactones. The following antioxidant, anti-inflammatory, immunomodulatory, and hepatoprotective compounds have been found in these plants: andrographolide, rosmarinic acid, phenol, eugenol, 9,12-octadecadienoic, n-hexadecanoic acid, dihydroxy dimethoxy flavone, sitosterol, demethoxycurcumin, quercetin, linoleic acid, stigmasterol, kojic acid, indole-2-one, α-terpinol, linalool, kaempferol, catechin, ellagic acid, and oleanolic acid. This paper aimed to provide an in-depth review of in vivo studies on Malaysian medicinal plants possessing hepatoprotective properties, phytochemical ingredients, and antioxidant mechanisms, with an emphasis on the species proven particularly useful for treating hepatic disorders. 相似文献
987.
Shujaat Ahmad Manzoor Ahmad Mazen Almehmadi Syed Adnan Ali Shah Farman Ali Khan Nasir Mehmood Khan Asifullah Khan Zainab Mustafa Halawi Hanif Ahmad 《Molecules (Basel, Switzerland)》2022,27(14)
This study reports the isolation of three new C20 diterpenoid alkaloids, Chitralinine A–C (1–3) from the aerial parts of Delphinium chitralense. Their structures were established on the basis of latest spectral techniques and single crystal X-rays crystallographic studies of chitralinine A described basic skeleton of these compounds. All the isolated Compounds (1–3) showed strong, competitive type inhibition against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in comparison to standard allanzanthane and galanthamine however, chitralinine-C remained the most potent with IC50 value of 11.64 ± 0.08 μM against AChE, and 24.31 ± 0.33 μM against BChE, respectively. The molecular docking reflected a binding free energy of −16.400 K Cal-mol−1 for chitralinine-C, having strong interactions with active site residues, TYR334, ASP72, SER122, and SER200. The overall findings suggest that these new diterpenoid alkaloids could serve as lead drugs against dementia-related diseases including Alzheimer’s disease. 相似文献
988.
Muhammad Ateeq Muhammad Muzammal Adeel Ayesha Kanwal Muhammad Tahir ul Qamar Ahsan Saeed Binish Khaliq Qamar Saeed Muhammad Nauman Atiq Muhammad Bilal Metab Alharbi Abdulrahman Alshammari Ahmed Akrem 《Molecules (Basel, Switzerland)》2022,27(10)
Vicilin has nutraceutical potential and different noteworthy medicative health-promoting biotic diversions, and it is remarkable against pathogenic microorganisms and insects. In this study, Vigna aconitifolia vicilin (VacV) has been identified and characterized from the seed of Vigna aconitifolia (Jacq.) Marechal (Moth beans). LC-MS/MS analysis of VacV provided seven random fragmented sequences comprising 238 residues, showing significant homology with already reported Vigna radiata vicilin (VraV). VacV was purified using ammonium sulfate precipitation (60%) followed by size exclusion chromatography on Hi-Load 16/60 Superdex 200 pg column and anion-exchange chromatography (Hi trap Q FF column). Purified VacV showed a major ~50 kDa band and multiple lower bands on 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under both reduced and non-reduced conditions. After all, a three-dimensional molecular structure of VacV was predicted, which showed β-sheeted molecular conformation similar to crystallographic structure of VraV. All Vicilins from V. aconitifolia and other plants were divided into six sub-groups by phylogenetic analysis, and VacV shared a high degree of similarity with vicilins of Vigna radiata, Pisum sativum, Lupinus albus, Cicer arietinum and Glycine max. Additionally, VacV (20 μg) has significant growth inhibition against different pathogenic bacteria along strong antifungal activity (50 μg). Likewise, VacV (3.0 mg) produced significant growth reduction in Rice Weevil Sitophilus oryzae larvae after 9 days compared with control. Furthermore, by using MMT assay, the cytotoxicity effect of VacV on the growth of HepG2 liver cancerous cells was tested. VacV showed cytotoxicity against the HepG-2 line and the acquired value was 180 µg after 48 h. Finally, we performed molecular docking against caspase-3 protein (PDB ID: 3DEI) for VacV bioactive receptor interface residues. Hence, our results reveal that VacV, has nutraceutical potential and moth beans can be used as a rich resource of functional foods. 相似文献
989.
Shahid Jamil Ghulam Dastagir Ahmed Ibrahim Foudah Mohammed Hamed Alqarni Hasan Soliman Yusufoglu Huda Mohammed Alkreathy
mer Ertürk Muhammad Abdur Rehman Shah Rahmat Ali Khan 《Molecules (Basel, Switzerland)》2022,27(19)
Background: Due to the high expense, less effectiveness and more side effects of available synthetic medicine, the researchers and communities are focusing on phyto-based natural bioactive compounds, which are considered safer for the treatment of syndromes and chronic diseases. Aim: The current project was aimed to determine the phytochemicals constituents available in the aerial parts of methanol extract of Carduus edelbergii via GC-MS, fabrication of AuNPs mediated with the mentioned extract; characterization and evaluation of antimicrobial, antioxidant and antidiabetic potency of the synthesized AuNPs. Methods: Confirmation of green synthesis of AuNPs, functional groups responsible for the reduction in Au+, size and crystallinity, morphology and quantity of gold (Au) were carried out by Ultraviolet-Visible (UV-Vis) spectroscopy, Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and dispersive X-ray (EDX), respectively, whereas in vitro antioxidant characteristics were assessed by DPPH and ABTS assays. Wistar albino rats were used to test the anti-diabetic properties of the methanol extract and AuNPs. Results: GC-MS revealed that the diluted methanol extract of Carduus edelbergii consists of about 19 chemical constituents. Among the identified compounds, the 13-Docosenoic acid, methyl ester, (Z)—has the highest concentration (38.16%), followed by 9-Octadecenoic acid, methyl ester, (E)—(15.72%) and n-Hexadecanoic acid (15.07%). Methanol extract and its fabricated nanoparticles showed significant antioxidant and antimicrobial activities. In vivo antidiabetic study revealed a noteworthy (p < 0.05) decline in body weight and HDL and elevated concentration of blood glucose, bilirubin, creatinine, urea, triglyceride, VLDL, LDL, ALP, ALT and AST in diabetic control. The said changes were recovered significantly (p < 0.05) by treatment of diabetic rats with methanol extract (150 and 300 mg/Kg BW) and AuNPs of Carduus edelbergii (5 and 10 mg/Kg BW). Conclusion: The green synthesized AuNPs exhibit significant antioxidant, antimicrobial and antidiabetic characteristics. 相似文献
990.
Ya-Hui Liu Wei Liu Zi-Li Zheng Xin Wei Nouman Ali Shah Hao Lin Bai-Song Zhao Shi-Shu Huang Jia-Zhuang Xu Zhong-Ming Li 《高分子科学》2021,39(9):1191-1199
Mimicking the complex structure of natural bone remains a challenge for bone tissue scaffolds. In this study, a novel processing strategy was developed to prepare the bone-like scaffolds that are featured by highly oriented and fully interconnected pores. This type of biomimetic scaffolds was evolved from solid phase stretching of immiscible polycaprolactone(PCL)/poly(ethylene oxide)(PEO) blends with cocontinuous structure and the pore morphology was inherited from selective extraction of water ... 相似文献