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31.
Qi Xu Ziyu Chen Borong Zhu Yiming Li Manju B. Reddy Huilin Liu Guodong Dang Qi Jia Xiaojun Wu 《Molecules (Basel, Switzerland)》2021,26(21)
Cinnamon procyanidin oligomers (CPOs) are water-soluble components extracted from cinnamon. This study aims to explore the neuroprotection of B-type CPO (CPO-B) against 1-methyl-4-phenylpyridinium (MPP+)-mediated cytotoxicity and the molecular mechanisms underlying its protection. The results demonstrated that CPO-B showed protection by increasing cell viability, attenuating an intracellular level of reactive oxygen species, downregulating cleaved caspase-3 expression, and upregulating the Bcl-2/Bax ratio. Moreover, CPO-B completely blocked the dephosphorylation of extracellular, signal-regulated kinase 1 and 2 (Erk1/2) caused by MPP+. Treatment with an Erk1/2 inhibitor, SCH772984, significantly abolished the neuroprotection of CPO-B against MPP+. Taken together, we demonstrate that CPO-B from cinnamon bark provided protection against MPP+ in cultured SH-SY5Y cells, and the potential mechanisms may be attributed to its ability to modulate the dysregulation between pro-apoptotic and anti-apoptotic proteins through the Erk1/2 signaling pathway. Our findings suggest that the addition of cinnamon to food or supplements might benefit patients with PD. 相似文献
32.
Dinesh Kumar Milind S. Ladaniya Manju Gurjar Sunil Kumar Sachin Mendke 《Molecules (Basel, Switzerland)》2021,26(14)
Physiologically dropped immature Citrus reticulata Blanco fruits are regarded as waste and discarded in the citrus orchard but are a good source of bioactive compounds including flavonoids, antioxidants and total phenols. A study was undertaken to identify and quantify these bioactive compounds and to investigate the influence of different drying techniques, namely freeze drying and hot air oven drying, on flavonoids namely flavanone glycosides, antioxidant potential and total phenol content in immature dropped fruits of Citrus reticulata Blanco. Flavonoids were quantified in high-performance liquid chromatography (HPLC). The antioxidant activity were investigated with three assays azino-bis [3-ethylbenzthiazoline-6-sulfonic acid]) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), Ferric Reducing Ability of Plasma (FRAP) and total phenol content was determined. Freeze dried samples of 12 and 14 mm size retained maximum hesperidin flavonoid content (27.03% and 27.20%) as compared to the hot air dried samples (17.99%) and retained higher phenolic content ranged from 50.54–54.19 mg GAEL−1. The antioxidant activity in freeze dried fruits was from 12.21–13.55 mM L−1 Trolox and 15.27–16.72 mM L−1 Trolox with ABTS, DPPH assay and FRAP values ranging from 7.31–9.07 mM L−1 Trolox. Significant positive correlation was found between the flavonoid hesperidin with antioxidant assays and total phenolic content (TPC). The results showed that waste citrus fruits can act as potential source of bioflavonoids, especially hesperidin, and antioxidants for pharmaceutical as well as nutraceutical industry. 相似文献
33.
A. Subbiah Pandi D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun M. C. Bansal 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o302-o304
The title compound, C19H20O6, crystallizes in the centrosymmetric space group P21/c with one molecule in the asymmetric unit. The molecule is approximately planar and the dihedral angle between the phenyl rings is 11.0 (1)°. The H atoms of the central propenone group are trans. There is an intramolecular O—H⃛O hydrogen bond and the molecules are crosslinked by four intermolecular C—H⃛O hydrogen bonds, producing a three‐dimensional network. 相似文献
34.
A procedure has been developed for the direct fourth-derivative spectrophotometric determination of iron(III) dimethyldithiocarbamate by converting it into an iron(II) 2,2'-bipyridyl complex, which is then dissolved in Triton X-100. Beer's law is obeyed over the concentration range 0.5-20 microg mL(-1 )in the final solution. Various parameters such as the effect of pH and interference of large number of ions on the determination of ferbam have been studied in detail. The method is sensitive, highly selective and can be used for the determination of ferbam in a commercial sample and in mixtures with various dithiocarbamates (ziram, zineb, maneb, etc.) and from wheat grains. 相似文献
35.
Anjleena Malhotra Tejinder Kaur Ranju Bansal 《Journal of heterocyclic chemistry》2019,56(10):2902-2911
In the present study, novel 4‐aryloxyquinazoline derivatives were synthesized and screened for in vitro cytotoxicity on human cancer cell lines at 10 μM. Some of the synthesized compounds displayed moderate to significant and selective cytotoxic activity against various leukemia, melanoma, ovarian, breast, and colon cancer cell lines. (E)‐3‐(3,4‐Dimethoxyphenyl)‐1‐(4‐(quinazolin‐4‐yloxy)phenyl)prop‐2‐en‐1‐one ( 9b ) was the most potent compound among all with an average growth inhibition of 70% against leukemia cancer cell lines. The compound also produced strong inhibition (75%) of colon cancer cell lines with 42.58% lethality of HCT‐116 cell line. 相似文献
36.
Sharvan Kumar Vikas Malik Jyoti Shukla Yogendra Kumar Deepak Bansal Prof. Dr. Ratnamala Chatterjee Prof. Dr. Pritam Mukhopadhyay 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(18):4740-4750
Organic spin-based molecular materials are considered to be attractive for the generation of functional materials with emergent optoelectronic, magnetic, or magneto-conductive properties. However, the major limitations to the utilization of organic spin-based systems are their high reactivity, instability, and propensity for dimerization. Herein, we report the synthesis, characterization, and magnetic and electronic studies of three ambient stable radical ions ( 1 a.+ , 1 b.+ , and 1 c.+ ). The radical ions 1 b.+ and 1 c.+ with BPh4− and BF4− counter anions, respectively, were synthesized in excellent yields by means of anion metathesis of 1 a.+ with Br− as its counter anion. Notably, synthesis of 1 a.+ was achieved in an ecofriendly, solvent-free protocol. The radical ions were characterized by means of single-crystal X-ray diffraction studies, which revealed the discrete nature of the radical ions and extensive hydrogen-bonding interactions within the radical ions and with the counter anions. Thus, radical ions can be organized to form infinite supramolecular arrays using weak noncovalent interactions. In addition, the Br−, BF4−, and BPh4− anions formed diverse types of anion–π interactions with the naphthalene and imide rings of the radical ions. The radical ions were characterized by means of X-band electron paramagnetic resonance (EPR) spectroscopy in solution and in the solid state. Magnetic studies revealed their paramagnetic nature in the range of 10 to 300 K. The radical ions exhibited high resistivity approaching the gigaohm (GΩ) scale. In addition, the radical ions exhibited panchromism. 相似文献
37.
Structural Chemistry - A theoretical investigation of the model diazotization/dediazotization of N-aminopiperidine and N-aminomorpholine at the DFT (B3LYP/6-31+G(d)) level indicated that the... 相似文献
38.
Structural Chemistry - The reaction of ethyl anthranilate with DMAD and with methyl propiolate in dichloromethane in the presence of ethylaluminium dichloride as catalyst at room temperature gives... 相似文献
39.
40.
Raoul Walther Anna K. Winther Anne Sofie Fruergaard Wouter vandenAkker Lise Srensen Signe Maria Nielsen Morten T. JarlstadOlesen Yitao Dai Henrik S. Jeppesen Paolo Lamagni Aleksandr Savateev Sren Lykke Pedersen Camilla Kaas Frich Ccile Vigier‐Carrire Nina Lock Mandeep Singh Vipul Bansal Rikke L. Meyer Alexander N. Zelikin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):284-288
Nanozymes, nanoparticles that mimic the natural activity of enzymes, are intriguing academically and are important in the context of the Origin of Life. However, current nanozymes offer mimicry of a narrow range of mammalian enzymes, near‐exclusively performing redox reactions. We present an unexpected discovery of non‐proteinaceous enzymes based on metals, metal oxides, 1D/2D‐materials, and non‐metallic nanomaterials. The specific novelty of these findings lies in the identification of nanozymes with apparent mimicry of diverse mammalian enzymes, including unique pan‐glycosidases. Further novelty lies in the identification of the substrate scope for the lead candidates, specifically in the context of bioconversion of glucuronides, that is, human metabolites and privileged prodrugs in the field of enzyme‐prodrug therapies. Lastly, nanozymes are employed for conversion of glucuronide prodrugs into marketed anti‐inflammatory and antibacterial agents, as well as “nanozyme prodrug therapy” to mediate antibacterial measures. 相似文献