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A one-pot procedure for the preparation of functionalized 1,4-dihydropyridines by three-component reaction using substituted heterocyclic aldehydes, ammonium acetate, and substituted β-ketoesters catalyzed by L-proline was described. Present protocol offers excellent yield up to 92%, flexibility with different substitution, convenient operation, and eco-friendliness. The synthesized products were confirmed by 1H-NMR, 13C-APT, and IR spectroscopy. Herein, final confirmation of the targeted motif was made by X-ray single-crystal analysis of representative compounds (4f, 4j, 4k, 4l, and 4o). The chemically synthesized compounds were evaluated for the antiproliferative activity by cell viability (MTT) assay and dual AO/EB (acridine orange/ethidium bromide)-staining method against human A549 lung cancer cell lines. The viability of the treated cell was evaluated adopting MTT assay. According to associated changes in cell membranes during the process of apoptosis, a clear difference was observed between normal cells, early and late apoptotic cells, and necrotic cells. All compounds were found effective against Saccharomyces cerevisiae which was confirmed by increased reactive oxygen species production and DNA damage as compared to untreated yeast cell culture. Altogether, these compounds showed promising hope for application in pharmaceutical aid against yeast infections. [ABSTRACT FROM AUTHOR]

Novel bent-core materials containing a central core of 2, 5-disubstituted thiophene with chalcone as the side arm were synthesized and characterized to determine the structure–property relationship. The structural difference between two materials is the linking group in the thiophene and chalcone side arm. Chalcone is linked with thiophene by ester group in material I, while ester group is replaced with imine group in material II. The change in linking group exhibited a drastic difference in their physicochemical and intramolecular behaviors. Material I exhibits a hexagonal columnar mesophase at below room temperature, whereas material II exhibits a crystalline phase. Both liquid crystalline and crystalline properties were examined from polarized optical microscopy (POM), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD) analyses. The highlight of this work is material I revealed a hexagonal columnar phase in the temperature ranges 22–38°C and undergoes photocrosslinking in UV light; contrarily, material II exhibits neither LC phase nor photocrosslinking property. [ABSTRACT FROM AUTHOR]

Reaction of tetraethoxysilane (TEOS) with substituted catechols (I-X), 7,8-dihydroxyflavone (XI), 3,3′,4′-trihydroxyflavone (XII), 3′,4′,5,7-tetrahydroxyflavone (XIII), and 9-phenyl-2,3,7-trihydroxy-6-fluorone (XIV) in the presence of an amine (molar ratio 1:3:2) in acetonitrile affords the corresponding dianionic hexacoordinate silicon(IV) complexes 1-15 having a “SiO6” structural fragment. The dianionic silicates were isolated as di-n-propylammonium/triethylammonium/di-n-butylammonium salts and were characterized by elemental analysis and various spectroscopic data (IR, 1H, 13C, and 29Si NMR). The solid state structures of compounds [(n-C3H7)2NH2]2[{Cl4C6O2}3Si] (1) and [(n-C3H7)2NH2]2[{Br4C6O2}3Si] (2) were determined by single crystal X-ray diffraction. Both 1 and 2 crystallize in the monoclinic space group C2/c and reveal (i) bidentate mode of ligation, (ii) octahedral coordination around silicon, and (iii) hydrogen bonding features. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT [ABSTRACT FROM AUTHOR]

In this paper, a Multi Objective Genetic Algorithm (MOGA) is proposed to derive the optimal machine-wise priority dispatching rules (pdrs) to resolve the conflict among the contending jobs in the Giffler and Thompson (GT) procedure applied for job shop problems. The performance criterion considered is the weighed sum of the multiple objectives minimization of makespan, minimization of total idle time of machines and minimization of total tardiness. The weights assigned for combining the objectives into a scalar fitness function are not constant. They are specified randomly for each evaluation. This in turn leads to the multidirectional search in the proposed MOGA, which in turn mitigates the solution being entrapped in local minima. The applicability and usefulness of the proposed methodology for the scheduling of job shops is illustrated with 28 benchmark problems available in the open literature. [ABSTRACT FROM AUTHOR]