30 research outputs found
An Efficient Synthesis of 2,4,5-Trisubstituted and 1,2,4,5-Tetrasubstituted Imidazoles Using Dihydroquinolines as Novel Organocatalyst
No full textPhI(OAc) 2 mediated an efficient Knoevenagel reaction and their synthetic application for coumarin derivatives
No full textOne-pot synthesis of 1,5-diketones from 3-acetyl-4-hydroxycoumarin and effective cyclization to unexpected 3,4-dihydropyridines
No full textA one-pot synthesis of new 4-hydroxycoumarin-based 1,5-diketones and effective cyclization to quite stable and unexpected 3,4-dihydropyridines has been developed.</p
‐Mediated One‐Pot Synthesis and their Antibacterial Activity of Flavone and Coumarin Based Isoxazoles Under Mild Reaction Conditions
No full textMediated Synthesis of Selected Heterocycles by Oxidative C−C Bond Cleavage of AcetophenoneDerivatives
No full text‐Mediated Efficient Oxidative Deoximation of Flavonoid Oximes under Mild Reaction Conditions
No full text
People’s Reflections in the City: Exploring the Painting Practices of Figurative Expressionism by Academic Research
No full textThis paper is a practical outcome of a multidisciplinary research project conducted by the authors on the contemporary and modern practices of the Improvisation in Arts. All the authors are research-oriented practitioners in the fields of visual arts, performance arts, multimedia, Information and communication technologies as well as vocational training. Furthermore, the drawings, paintings, and sketches are all made by the correspondent author Assistant Professor Dr. Mohammed Baker Mohammed Al-Abbas as part of his research-oriented artistic practice through the hybrid painting techniques. Abstract The present studio-based paper aims to explore the creative reflections of the aesthetics of otherness within the practical phases of the painting production. This paper represents an experimental endeavor to create a two-dimensional artwork, which is a hybrid painting technique on canvas with mixed media and acrylic paints. Within such a specific practice-based context, each phase of this practical approach outlines a critical significance from the first phase of creating that painting to the completing phase. The practical methodology is the tool that converts the researcher's/artist's vision into creative academic production. The process of creating the painting on the canvas is the methodology; such manner turns to be a primary reference for the present exploration. There is a significant paradigm in this approach, which focuses on the artwork as a morphological creature being created by the researcher/artist rather than a consequent result that only exists as a finished/complete/polished outcome. The outcome of this research is the record of the artwork production itself. This record presents visual references of the artwork progress as well as a textual reflective narrative to describe this process with written words. This research-oriented artistic attempt introduces the artists and researchers in the domains of the Fine Arts to integrate the process of art-making into the methodologies of academic research. It is an academic text, reflective text as well as sequential images recording the artwork making. This studio-based experimentation is significant because it examines the aesthetics of the otherness into the expressive figurative abstraction in painting. Furthermore, the impact of such a studio-based approach manifests on advancing applications of the artistic oriented research in the field of Fine Arts globally on curatorial and academic levels. Keywords: Contemporary Art Practice, Studio-Based Methodology, Practice-Based Research, Hybrid Painting Techniques, Multimedia, Mixed media, Photography DOI: 10.7176/JEP/11-10-08 Publication date: April 30th 202
Divergent synthesis of fused Benzo-xanthene and oxazine derivatives via Cu-catalyst
No full textCu-Cu2O combination showed synergic effects in catalyzing intramolecular Ullmann coupling reaction for halo-Betti bases to afford fused benzo-xanthenes from both electron-rich and electron-deficient aromatic systems in good yield under mild reaction conditions. The sterically hindered halo-Betti bases also provided products in excellent yield. Under optimized condition, a gram scale reaction was also performed to afford the product in excellent yield. However, without ortho-halo substituted Betti-bases failed to afford fused benzo-xanthene derivatives. Exploring the reaction optimization without Cu metal, serendipitously it was produced 1,3-oxazine derivatives in excellent yield via intramolecular cross-dehydrogenative coupling (CDC) reaction. Similarly, electron-rich, electron-deficient and sterically hindered Betti-bases provided the products in good to excellent yield under mild condition
Hybrid <i>N</i>‑Acylcysteines as Dual-Acting Matrix Disruptive and Anti-Quorum Sensing Agents Fighting Pseudomonas aeruginosa Biofilms: Design, Synthesis, Molecular Docking Studies, and <i>In Vitro</i> Assays
No full textBiofilms facilitate the pathogenesis of life-threatening Pseudomonas aeruginosa infections by coating mucosal
surfaces or invasive devices and offer protection from antimicrobial
therapy and the host immune response, thus increasing mortality rates
and financial burden. Herein, new hybrid N-acylcysteines
(NAC) incorporating selected acyl groups from organic acids and their
derivatives, which are capable of quenching pathogen quorum sensing
(QS) systems, were designed and their antibiofilm activity and anti-QS
were evaluated. N-acylcysteines (4a–h) were synthesized and characterized by 1H NMR and 13C NMR, and their purity was confirmed by elemental analyses. N-(4-Hydroxy-3,5-dimethoxybenzoyl)-l-cysteine (4d) and N-(4-methoxybenzoyl)-l-cysteine
(4h) showed a higher antibiofilm activity against PAO1
biofilms than the rest of the targets and the standard NAC. They showed
83 and 82% inhibition of biofilms at 5 mM and eradicated mature biofilms
at 20 mM concentrations (NAC biofilm inhibition = 66% at 10 mM and
minimum biofilm eradication concentration = 40 mM). This was confirmed
via visualizing adherent biofilm cells on catheter pieces using scanning
electron microscopy. In the same vein, both 4d and 4h showed the highest docking score with the QS signal receptor
protein LasR (−7.8), which was much higher than that of NAC
(−5) but less than the score of the natural agonist N-(3-oxododecanoyl)-l-homoserine (OdDHL) (−8.5).
Target 4h (5 mM) decreased the expression of quorum sensing
encoding genes in P. aeruginosa PAO1
strain by 53% for pslA, 47% for lasI and lasR, and 29% for filC, lowered
PAO1 pyocyanin production by 76.43%, completely blocked the proteolytic
activity of PAO1, and did not affect PAO1 cell viability. Targets 4d and 4h may find applications for the prevention
and treatment of biofilm-mediated P. aeruginosa local infections of the skin, eye, and wounds. N-(4-Methoxybenzoyl)-l-cysteine 4h is a promising
dual-acting matrix disruptive and anti-QS antibiofilm agent for further
investigation and optimization
