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241.
Najeeb Ur Rehman Hidayat Hussain Mohammed Khiat Samia Ahmed Al‐Riyami René Csuk Husain Yar Khan Ghulam Abbas Ghanim Salim Al‐Thani Ivan R. Green Ahmed Al‐Harrasi 《Helvetica chimica acta》2016,99(9):687-690
Two new C‐glucosyl chromones named aloeverasides A ( 1 ) and B ( 2 ) were isolated from the resin of Aloe vera (L.) Burm.f . The structures of the two new natural products were elucidated based on 1D‐ (1H‐ and 13C‐NMR) and 2D‐NMR (COSY, HSQC, and HMBC) spectroscopic techniques and mass spectrometry (ESI‐MS). Aloeverasides A ( 1 ) and B ( 2 ) were evaluated for their anticancer activity, and both induced a 76.4 and 70.5% growth inhibition of the breast cancer cell line (MDA‐MB‐231) at a concentration of 100 μm . Both compounds were also evaluated for their 1,1‐diphenyl‐2‐picryl‐hydrazyl antioxidant, urease enzyme, and α‐glucosidase enzyme inhibition activities. Aloeverasides A ( 1 ) and B ( 2 ) displayed good urease enzyme inhibition activities (62 and 55%, resp.), as well as antioxidant activity in which aloeveraside A ( 1 ) had a value of 60% inhibition, while aloeveraside B ( 2 ) demonstrated a more potent antioxidant activity with 80% inhibition. 相似文献
242.
Electron‐Poor Thiophene 1,1‐Dioxides: Synthesis,Characterization, and Application as Electron Relays in Photocatalytic Hydrogen Generation 下载免费PDF全文
Chia‐Hua Tsai Danielle N. Chirdon Husain N. Kagalwala Andrew B. Maurer Aman Kaur Prof. Tomislav Pintauer Prof. Stefan Bernhard Prof. Kevin J. T. Noonan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11517-11524
The synthesis and characterization of electron‐poor thiophene 1,1‐dioxides bearing cyanated phenyl groups are reported. The electron‐accepting nature of these compounds was evaluated by cyclic voltammetry, and highly reversible and facile reductions were observed for several derivatives. Moreover, some of the reduced thiophene dioxides form colorful anions, which were investigated spectroelectrochemically. Photoluminescence spectra of the electron‐deficient sulfones were measured in CH2Cl2, and they emit in the blue‐green region with significant variation in the quantum yield depending on the aryl substituents. By expanding the degree of substitution on the phenyl rings, quantum yields up to 34 % were obtained. X‐ray diffraction data are reported for two of the thiophene 1,1‐dioxides, and the electronic structure was probed for all synthesized derivatives through DFT calculations. The dioxides were also examined as electron relays in a photocatalytic water reduction reaction, and they showed potential to boost the efficiency. 相似文献
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Dixit Veena Irshad Saba Singh Harsh Agnihotri Priyanka Husain Tariq Khatoon Sayyada 《平面色谱法杂志一现代薄层色谱法》2017,30(1):25-31
JPC – Journal of Planar Chromatography – Modern TLC - This study was designed to develop a simple, sensitive, selective, and precise high-performance thin-layer chromatography (HPTLC)... 相似文献
245.
Abdul Qadir Nausheen Khan Muhammad Arif Musarrat Husain Warsi Shehla Nasar Mir Najib Ullah Mohammad Yusuf 《印度化学会志》2022,99(6):100503
Trigonella foenumgraecum L. (TF) is a medicinal herb, belonging to the family Legumes. It has shown positive results in remedying hypo-cholesterolemic, anti-inflammatory, antibacterial, antioxidant, anti-lipidemia, antilithigenic, hepatoprotective, antiulcer, anticarcinogenic, antifungal and other miscellaneous pharmacological effects of fenugreek. The n-hexane extract of Trigonella foenumgraecum L. Seeds (TF) was analysed by gas chromatography-mass spectroscopy for identification and characterization of its therapeutic claim by traditional system. DPPH method was used to determine the antioxidant activity of Trigonella foenumgraecum L-seeds extract using UV spectrophotometer at a wavelength of 518 nm as it is one of the most sorted methods for antioxidant activity. The major compounds discovered in Trigonella foenumgraecum L. seeds extract are Linoleic acid (48.01%); 9,12-Octadecadienoic acid (Z,Z)-, 2,3-dihydroxypropyl ester (24.65%); 2-[4-Methyl-6-(2,6,6-trimethylcyclohex-1-enyl)hexa-1,3,5-trienyl]cyclohex-1-en-carboxaldehyde(1.88%); Nonane dioic acid, bis (2-ethylhexyl) ester (1.09%); Bis (2-ethylhexyl) ester of azelaic acid (11.97%); Elemicin (0.51%); cis-Linoleic acid methyl ester (0.76%); Linoleic acid chloride(0.57%); Ethyl oleate(0.18%); Isopropyl linoleate (0.38%); Dihydrovallesiachotamine (0.06%); 4-(2,2-Dimethyl-6-methylenecyclohexyl) butanal(0.12%); Citronellyl myristate (0.09%); Rhaphidecursinol B(0.25%); 5-Methoxygalbelgin (0.07%); Vitamin E (0.31%); 1,1,1,5,5,5-hexafluoro-4-{[3-(trifluoromethyl) phenyl]imino}-2-pentanone (0.76%); γ-Sitosterol (0.66%); 1-(1,5-Dimethylhexyl)-3a,12a-dimethyltetradecahydro-1H-cyclopenta[a]cyclopropa[e]phenanthren-7-ol (0.16%) and (9Z)-9-Octadecenyl (9Z)-9-hexadecenoate (1.57%). The results showed potential antioxidant activity of n-hexane extract of Trigonella foenumgraecum L. seeds by showing significant reduction in free radical against DPPH. The hexane extract of Trigonella foenumgraecum L. seeds comprises various non-water-soluble (nonpolar) constituents. These compounds were established qualitatively via GC-MS evaluation. The free radical scavenging activity of the plant extract was established owning to the presence of compounds such as terpenes, vitamin E, and unsaturated fatty acids. 相似文献
246.
Kumar Dinesh Srivastava Sanjay K. Singh P. K. Sood K. N. Singh V. N. Dilawar Nita Husain M. 《Journal of nanoparticle research》2010,12(6):2267-2276
Journal of Nanoparticle Research - We report a simple, inexpensive, and rapid process for large area growth of vertically aligned crystalline silicon nanowires (SiNWs) of diameter... 相似文献
247.
JPC – Journal of Planar Chromatography – Modern TLC - Rapid separation of methyl p-hydroxybenzoate from ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, p-hydroxybenzoic acid, benzoic... 相似文献
248.
Arackal Jose Jobil Sakthivelan Parameshwari Fohad Mabood Husain Suliman Yousef Alomar Naushad Ahmad Fadwa Albalawi Pravej Alam 《Molecules (Basel, Switzerland)》2021,26(24)
The study’s purpose was to find and create a nourishing fruit juice made from avocado to suit nutritional and health demands. In this regard, the avocado juice was formulated using a statistical technique, and its biochemical and phytochemical characteristics were evaluated. Statistically formulated fruit juice was evaluated for its sensory characteristics, proximate composition, nutrients and vitamins, total phenols and flavonoids, and for its antioxidant ability, in addition to a shelf-life test. The optimal amount of all ingredients included in the mathematical model for the preparation of the juice was 150 g of Persea americana (Avocado) fruit pulp, 12.5 g of honey and 100 mL of water. In fact, the composition of avocado juice was found to have higher phenolic (910.36 ± 0.215 mg EAG g−1/mL) and flavonoid (56.32 ± 1.26 mg QE g−1/ mL) amounts. DPPH, ABTS and FRAP antioxidant assays tended to be high compared with a standard. The shelf-life analysis indicated that the processed avocado juice (V7) had a long shelf life. In view of all these merits, a statistically formulated recipe for avocado fruit juice was recommended for the formulation of the most preferred health drink. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - 相似文献