1H-1,2,3-Triazolyl-substituted 1,3,4-oxadiazole derivatives containing structural features of ibuprofen/naproxen: Their synthesis and antibacterial evaluation

Copper(II) complexes of chromen-2-one-3-carboxyhydrazide and 2-(chromen-3'-onyl)-5-(aryl)-1,3,4-oxadiazole derivatives have been synthesized. The structural features have been determined from their microanalytical, magnetic susceptibility, molar conductance, IR, UV Vis,1H NMR and ESR spectral data. All the Cu(II) complexes exhibit the composition Cu(Ln)2X2; where L1= chromen-2-one-3-carboxy hydrazide, L2 = 2-(chromen-3'-onyl)-5-(2ʺ-hydroxy phenyl)-1,3,4-oxadiazole, L3 = 2-(chromen-3'-onyl)-5-(4ʺ-nitrophenyl)-1,3,4 -oxadiazole and L4 = 2-(chromen-3'-onyl)-5-(4ʺ-chlorophenyl)-1,3,4-oxadiazole; X = Cl-, Br-, NO3-, CH3COO-, ClO4-and CNS-. The N, O donor ligands act as a bidentate ligand in all the complexes. Distorted octahedral geometry for all the Cu(II) complexes is proposed. Molecular modeling studies have been made for the rapid structure building, geometry optimization and molecular display. These complexes show the conductance values, supporting their non-electrolytic nature. The monomeric nature of the complexes was confirmed from their magnetic susceptibility values. These complexes have been screened for their antimicrobial activities against some bacterial species likeS.aureus, E.coli, Pseudomonas aeruginosaand few fungal strainsC.albicansandCryptococcus neoformans.

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Synthesis, characterization and antibacterial evaluation of 1,3,4-oxadiazole derivatives

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v10i3.1477 ◽

2019 ◽

Vol 10 (3) ◽

pp. 2342-2350

Author(s):

Suhail H. Derawey ◽

Mazin N. Mosa ◽

Ekhlas Qanber Jasim ◽

Rawaa M. O. Hraishawi

Keyword(s):

Pseudomonas Aeruginosa ◽

Inhibition Zone ◽

Significant Inhibition ◽

Synthesis And Characterization ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Oxadiazole Derivatives ◽

And Staphylococcus Aureus ◽

Antibacterial Evaluation

The present work includes synthesis and characterization of some novel 1,3,4-oxadiazole derivatives and the evaluation of the antibacterial activity of the synthesized compound against pathogenic isolated gram-negative and gram-positive bacteria. The activity result showed that some compound exhibited efficient effect against these bacteria. Some compounds had significant inhibition zone against Escherichia coli, pseudomonas aeruginosa and Staphylococcus aureus. The compound OXD3 and OXD4 gave inhibition zone against resistant pseudomonas aeruginosa while stander drug cefepime doesn’t give an activity.

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Electron microscopy and diffraction studies of polyimides

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074069 ◽

1983 ◽

Vol 41 ◽

pp. 28-29

Author(s):

O.C. de Hodgins ◽

K. R. Lawless ◽

R. Anderson

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Structural Features ◽

Inert Atmosphere ◽

Polyimide Films ◽

Resolution Electron ◽

The Matrix ◽

High Resolution Electron Microscope ◽

Diffraction Patterns ◽

Polymeric Samples

Commercial polyimide films have shown to be homogeneous on a scale of 5 to 200 nm. The observation of Skybond (SKB) 705 and PI5878 was carried out by using a Philips 400, 120 KeV STEM. The objective was to elucidate the structural features of the polymeric samples. The specimens were spun and cured at stepped temperatures in an inert atmosphere and cooled slowly for eight hours. TEM micrographs showed heterogeneities (or nodular structures) generally on a scale of 100 nm for PI5878 and approximately 40 nm for SKB 705, present in large volume fractions of both specimens. See Figures 1 and 2. It is possible that the nodulus observed may be associated with surface effects and the structure of the polymers be regarded as random amorphous arrays. Diffraction patterns of the matrix and the nodular areas showed different amorphous ring patterns in both materials. The specimens were viewed in both bright and dark fields using a high resolution electron microscope which provided magnifications of 100,000X or more on the photographic plates if desired.

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053310 ◽

1982 ◽

Vol 40 ◽

pp. 118-119

Author(s):

U. Aebi ◽

P. Rew ◽

T.-T. Sun

Keyword(s):

Electron Microscopy ◽

Structural Organization ◽

Cell Types ◽

Structural Features ◽

Molecular Architecture ◽

The Past ◽

Keratin Filaments ◽

Different Types ◽

10 Nm Filaments ◽

Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

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Measurement and Reduction of Radiation Damage in Frozen Hydrated Crystalline Specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069867 ◽

1978 ◽

Vol 36 (3) ◽

pp. 70-77 ◽

Cited By ~ 1

Author(s):

R.M. Glaeser ◽

S.B. Hayward

Keyword(s):

Diffraction Pattern ◽

Structural Information ◽

Structural Disorder ◽

Structural Features ◽

Biological Macromolecules ◽

Diffraction Intensity ◽

Object Structure ◽

Specimen Material ◽

Unit Cells ◽

Identical Unit

Highly ordered or crystalline biological macromolecules become severely damaged and structurally disordered after a brief electron exposure. Evidence that damage and structural disorder are occurring is clearly given by the fading and eventual disappearance of the specimen's electron diffraction pattern. The fading and disappearance of sharp diffraction spots implies a corresponding disappearance of periodic structural features in the specimen. By the same token, there is a oneto- one correspondence between the disappearance of the crystalline diffraction pattern and the disappearance of reproducible structural information that can be observed in the images of identical unit cells of the object structure. The electron exposures that result in a significant decrease in the diffraction intensity will depend somewhat upon the resolution (Bragg spacing) involved, and can vary considerably with the chemical makeup and composition of the specimen material.

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