1,049 research outputs found

    Multiple Triple-Point Fermions in Heusler Compounds

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    Using the density functional theoretical calculations, we report a new set of topological semimetals X2_{2}YZ (X = \{Cu, Rh, Pd, Ag, Au, Hg\}, Y = \{Li, Na, Sc, Zn, Y, Zr, Hf, La, Pr, Pm, Sm, Tb, Dy, Ho, Tm\} and Z =\{Mg, Al, Zn, Ga, Y, Ag, Cd, In, Sn, Ta, Sm\}), which show the existence of multiple topological triple point fermions along four independent C3C_{3} axes. These fermionic quasiparticles have no analogues elementary particle in the standard model. The angle-resolved photoemission spectroscopy is simulated to obtain the exotic topological surface states and the characteristic Fermi arcs. The inclusion of spin-orbit coupling splits the triple-point into two Dirac points. The triple-point fermions are exhibited on the easily cleavable (111) surface and are well separated from the surface Γˉ\bar{\Gamma} point, allowing them to be resolved in the surface spectroscopic techniques. This intermediate linearly dispersive degeneracy between Weyl and Dirac points may offer prospective candidates for quantum transport applications

    SYNTHESIS AND ANTI-INFLAMMATORY ACTIVITY OF SOME NOVEL 1,5 BENZODIAZEPINE DERIVATIVES

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    ABSTRACTObjective: The objective of the study is to synthesize some novel 1,5-benzodiazepine derivatives from chalcones. The structures of the newlysynthesized compounds were characterized by elemental analysis, infrared, H nuclear magnetic resonance, and mass spectroscopic studies. All titledcompounds were screened for their anti-inflammatory activity.1Methods: In this study, a series of novel 2-(substituted phenyl)-3-styryl-2,3-dihydro-1H-benzo [b] [1,4] diazepine (1-12) has been synthesizedfrom 1,5-(disubstituted phenyl)-2,4-pentadien-1-one (1a-12a). 1,5-(disubstituted phenyl)-2,4-pentadien-1-one was prepared by condensingcinnamaldehyde with various aromatic ketones in the presence of 20% NaOH as base. Different 1,5-(disubstituted phenyl)-2,4-pentadien-1-one oncyclisation with o-phenylene diamine in the presence of NaOH as base resulted in 2-(substituted phenyl)-3-styryl-2,3-dihydro-1H-benzo [b] [1,4]diazepine derivatives. The final synthesized benzodiazepine derivatives were screened for their anti-inflammatory activity using carrageenaninducedratpawedema method.Results: The compounds 4, 5, 7, 9, 10, 11, and 12 containing 4-nitrophenyl, 4-chlorophenyl, 3-nitro phenyl, 4-fluorophenyl, 4-bromophenyl, and3-chlorophenyl benzodiazepine derivatives exhibited significant anti-inflammatory activity compared with the standard diclofenac sodium Thepresence of electron withdrawing groups such as nitro, chloro, fluoro, and bromo resulted in increased anti-inflammatory activity.Conclusion: This study reports the successful synthesis of 1,5-benzodiazepine derivatives with moderate yields and most of the synthesizedcompounds showed significant anti-inflammatory activity.Keywords: Chalcones, 1,5-benzodiazepines, Anti-inflammatory activity

    PYRAZOLINES AS POTENT ANTITUBERCULAR AND CYTOTOXIC AGENTS

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    Objective: Pyrazolines are known to exhibit different biological and pharmacological properties such as anticancer, antibacterial, antifungal and antitubercular activities. Chalcones with an enone group between two aromatic rings exhibit remarkable pharmacological activities such as antiinflammatory, antibacterial, antitumor, antifungal, and antimalarial activity. A series of pyrazolines from chalcones have been synthesized and evaluated for antitubercular and cytotoxic activity studies.Methods: Chalcones [3-substituted phenyl-1-(p-tolyl)prop-2-en-1-one] were synthesized from various substituted aldehydes and 4-methyl acetophenone and cyclized into pyrazolines [5-substituted phenyl-3-(p-tolyl)-4,5-dihydro-1H-pyrazole] using hydrazine hydrate. Antitubercular and cytotoxic activity studies were carried out.Results: Antitubercular and cytotoxic activity studies of synthesized pyrazoline revealed that some compounds have showed promising activity.Conclusion: The observed results proved that pyrazolines are found to be interesting lead molecules for further synthesis as antitubercular and cytotoxic agents
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