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n-Hexane extract of rhizomes of Imperata cylindrica var. koenigii f. pallida yielded five novel skeletal triterpenoids, designed as impallidin (1), impallidol (2), impallidin ozonide (3a, 3b), trisnorimpallidin aldehyde (4), tetranorimpallidin aldehyde (5). Structures of novel compounds were elucidated by mainly 2D NMR and other spectroscopic analysis and chemical ...
Continue readingWe report the iridium-catalyzed branch-selective hydroalkylation of simple alkenes such as aliphatic alkenes and aromatic alkenes with malonic amides and malonic esters under neutral reaction conditions. A variety of aliphatic alkenes and aromatic alkenes bearing bromine, chlorine, ester, 2-thienylcarboxylate, silyl, and phthalimide groups were all found to be suit...
Continue readingHere we report an ortho-C–H alkenylation of aromatic ketones with unsymmetric internal alkynes catalyzed by an iron phosphine complex, Fe(PMe3)4. The use of a catalytic amount of PtBu3 as an additive was found to improve the product yields. The alkenylation proceeds regio- and stereoselectively to give the corresponding styrene derivatives.
Continue readingIn this work, a novel crystal, (E)-4-(4-methylbenzyl)-6-styrylpyridazin-3(2H)-one (E-BSP) was synthesized via Knoevenagel condensation of benzaldehyde and (E)-6-(4-methoxystyryl)-4,5-dihydropyridazin-3(2H)-one. The molecular structure of E-BSP was confirmed by using FT-IR, 1H-NMR, 13C-NMR, UV-vis, ESI-MS, TGA/DTA thermal analyses and single crystal X-ray diffractio...
Continue readingThe Lower Cretaceous of northwest Tunisia shows a large series of clayey materials for use in the ceramics industry. The Mineralogical, chemical, thermal analyses, technological proprieties and grain size distribution were carried out on clay samples selected from areas of Oued Zarga. Clay materials are considered illite clays associated with smectite. Chemical a...
Continue readingA gram-scale syn-selective asymmetric vinylogous addition of butenolides to chromones, catalyzed by an Al-Li-BINOL (ALB) complex, was developed in this study. For various combinations of substrates, the observed diastereoselectivity approached 20:1 with 84–98% ee. This protocol is complementary to previously reported ones and improves the selectivity for seve...
Continue readingA natural attractant for Ceratitis capitata developed by microencapsulation by coacervation complex with gelatin and gum arabic of the essential oil of Ruta graveolens was evaluated. Essential oil composition was analyzed by Gas Chromatography Mass Spectrometry (GC/MS). Microencapsulation efficacy was evaluated by determination of the encapsulation yield (%), encap...
Continue readingIn this research, we investigated the structural and biological properties of phosphate glasses (PGs) after the addition of V2O5. A xV2O5∙(100 − x)[CaF2∙3P2O5∙CaO] glass system with 0 ≤ x ≤ 16 mol% was synthesized via a conventional melt-quenching technique. Several analysis techniques (dissolution tests, pH, SEM-EDS, FT-IR, and EPR) were used to obta...
Continue readingControlling bioactive components' crystal growth, especially for hydrophobic functional factors, is an effective pathway for achieving their stabilization. Here, our paper proposes a method utilizing hydrogel to regulate crystal growth, using nobiletin (NOB) as a model. Results showed that the NOB crystallization was controlled by gellan gum (GG) concentrations...
Continue readingTo look in-depth into the traditional Mexican truffle, this study investigated the phytochemical and pharmacological properties of field-collected corn galls and the fermentate of its pathogen Ustilago maydis MZ496986. Here, we established the chemical profiles of both materials via the gradient HPLC-UV method and successfully identified six previously unreported c...
Continue readingThis study deal with introducing a novel biocompatible porous nanomaterial for anticancer drug delivery. For this purpose, a porous covalent triazine framework (CTF) was prepared by a solvothermal reaction. The structure and morphology characterization of the synthesized CTF was done through different techniques. Imatinib (IMA) were loaded thoroughly into the CTF...
Continue readingPolyethylene Glycol (PEG)-based flexible phase change materials have broad and practical application value in thermal management of flexible electronic devices. Considering the typical application cases and safety of phase change materials (PCMs), in this work, we grafted molecular nanoparticles, POSS, with both hydrophobic and flame retardant functions to the surf...
Continue readingMetal nanoclusters of atomic precision have recently emerged as potential candidates for nonlinear optical applications owing to their strong quantum confinement effects. Herein, we report the nonlinear absorptive and refractive properties of platinum-17 (Pt17) metal nanoclusters stabilized by carbon monoxide and triphenyl phosphine ligands. The open aperture z-sca...
Continue readingInjuries to the nervous system account for the widespread morbidity, mortality, and discomfort worldwide. Artificial nerve guidance conduits (NGCs) offer a promising platform for nerve reconstruction, however, they require extracellular matrix (ECM)-like features to better mimic the in vivo microenvironment. Consequently, this research was aimed to fabricate hepari...
Continue readingConvergent and scalable synthesis of the ABCDE-ring fragment of Caribbean ciguatoxin C-CTX-1, the major causative toxin for ciguatera poisoning in the Caribbean Sea and the Northeast Atlantic areas, is described in detail. The key features of the synthesis include an iterative use of 2,2,6,6-tetramethyl piperidine 1-oxyl (TEMPO)/PhI(OAc)2-mediated oxidative lactoni...
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