Preferred Language
Articles
/
aRcH6o8BVTCNdQwCDYC3
Synthesis and study the liquid crystalline properties of new compounds containing 5-methyl-2,4-dihydro-3H-pyrazol-3-one
...Show More Authors
Abstract<p>The new compounds of pyrazolines were synthesized from the reaction of different acid hydrazide with ethylacetoacetate and ethanol under reflux. These compounds were obtained from many sequence reactions. The 4-acetyl-5-methyl-2,4-dihydro-3H-pyrazol-3-one compounds synthesized from the reaction of 5-methyl-2,4-dihydro-3H-pyrazol-3-one with acetyl chloride in calcium hydroxide and 1,4-dioxane. Finaly, Schiff bases were prepared via condensation reaction of products of mono- and tri ketone derivatives[IV]<sub>a, b</sub> with phenyl hydrazines as presented in (Scheme 1, 2). The synthesized compounds were identification by using FTIR, NMR and Mass spectroscopy (of some of them). The mesomorphic behaviour of these derivatives were examined under OPM. The compound [IV]<sub>a</sub> exhibited enantiotropic liquid crystal (Smectic A on heating and Nematic on cooling) while the compound [V]<sub>c</sub> showed Smectic A and nematic phases only on cooling (monotropic). Also the two compounds [V]<sub>a</sub> and [VI]<sub>b</sub> exhibited nematic mesophase on cooling. The compound [IV]<sub>b</sub>, [V]<sub>b, d</sub> and [VI]a, c, d did not show any mesomorphic properties.</p>
Scopus Crossref
View Publication
Publication Date
Thu Jul 18 2002
Journal Name
Phase Transitions
Designed new mesogens via Vilsmeier–Haack reagent: synthesis and phase transition study
...Show More Authors

A new four series of 2,2′-([1,1′- phenyl or biphenyl]-4,4′-diylbis(azanediyl)) bis(N′-((E)-1-(4-alkoxyphenyl) ethylidene) acetohydrazide) [V-XI]a,b and 1,1′-(2,2′-([1,1′- phenyl or biphenyl]-4,4′-diyl bis(azanediyl)) bis- (acetyl)) bis(3-(4-ethoxyphenyl)-1H-pyrazole-4-carbalde hyde) [XII-XVIII]a,b have been synthesized by varying terminal lateral alkoxy chain length (n = 1–3, 5–8), central linkage group (phenyl or biphenyl) and induced pyrazole heterocyclic ring in the main chain. The last two series were synthesized by the cyclization of substituted acetophenone hydrazones with Vilsmeier–Haack reagent (DMF/POCl3) to produce 4-formylpyrazole derivatives. The chemical structures of the synthesized compounds were examine

... Show More
Scopus (2)
Scopus
Publication Date
Thu Jun 19 2025
Journal Name
Journal Of Baghdad College Of Dentistry
An Evaluation of Some Mechanical Properties of Autopolymerizing Acrylic Resin with the Modified One after Changing the Curing Environment: (In vitro Study)
...Show More Authors

Background: Studying and investigating the transverse strength(Ts), impact strength(Is), hardness (Hr) and surface roughness(Ra) of conventional and modified autopolymerizing acrylic resin with different weight percentages of biopolymer kraftlignin, after curing in different water temperatures; 40°C and 80°C. Material and Methods: Standard acrylic specimens were fabricated according to ADA specification No.12 for transverse strength, ISO 179 was used for impact testing, Shore D for hardness and profilometerfor surface roughness. The material lignin first dispersed in the monomer, then the powder PMMA is immediately added. Ligninadded in different weight percentages. Then cured using pressure pot (Ivomet) in two temperatures;40°C a

... Show More
View Publication Preview PDF
Publication Date
Sat May 13 2023
Journal Name
Journal Of Population Therapeutics And Clinical Pharmacology
Synthesis, Characterization of Schiff's and Mannich bases of 5-Fluoroisatin and Preliminary Antimicrobial Evaluation
...Show More Authors

With the aim of developing potential antimicrobials, a series of new 5-fluoroisatin derivatives incorporated with different secondary amines (piperidine, morpholine, pyrrolidine, dimethylamine, and diphenylamine) for monomer, and (piperazine) in case of dimer Mannich bases, separately in presence of formaldehyde to obtain Mannich bases of 5-fluoroisatin derivatives, which then each Mannich derivatives reacts with phenylhydrazine to form Schiff bases as final products. The resulting compounds were characterized by two spectroscopic analyses; (Fourier- transform infrared) FT-IR and proton nuclear magnetic resonance spectroscopy (¹H-NMR). In addition, the in vitro antibacterial and antifungal activities were tested against some human pathogen

... Show More
View Publication
Crossref
Publication Date
Sun Dec 15 2019
Journal Name
Journal Of Global Pharma Technology
synthesis and characterization of heterocyclic compounds and polymers with studying the biological activity for some of them
...Show More Authors

This paper deals with the preparation of new monomers and polymers which including heterocyclic unit. The diacid chlorides compounds [1-3] were prepared from the reaction of glutaric acid, adipic acid, terephthalic acid with thionyl chloride. Succinic acid reacted with ethanol to produce compound [4]. Compound [4] reacted with hydrazine hydrate to obtain succinic hydrazide [5].Compound [5] reaction with CS2 and KOH in absolute ethanol to produce compound [6].The polymers [7-12] have been created by reacting diacid chlorides compounds [1-3] with compound[5] or [6] in dry pyridine with some drops of DMF. The topology of produced compounds has characterized through their spectral and analytical data as in FT-IR spectra, Thermal analysis [DSC,

... Show More
Scopus
Publication Date
Fri Sep 22 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of Some Inorganic Compounds and Study their Effect in activity of Laccase Produced by Fungal isolate Pleurotus ostreatus
...Show More Authors

The new ligand(OBTMRZ),Bis[4-phenyl-3(2-propenyl)thio-1,2,4- triazole  -5yl] methane  was prepared and characterized by vibrational

 

,

 

,

 

spectra  and J>hysical methods,selected metals,which  were Cu11

 

Zn 11

 

Mn11,Co11,Fe"  and  Hg11   were  reacted   with  ligand   to &

... Show More
View Publication Preview PDF
Publication Date
Sat Apr 01 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Synthesis of 3 - 3 - gem - di - C -Nitromethyl Nucleoside Analogues of Possible Biological Activity
...Show More Authors

Synthesis of new nucleoside analogues of the type : 3¢ , 3¢ - gem – di – C – nitromethly , expected to have useful application in the chemotherapeutic treatment of AIDS , cancer and microbial infections. The synthesis involved the condensation of the appropriate sugar derivative ( i.e . 3¢ , 3¢ –  gem – di – C – nitromethly – 1–  ribofuranose ) with nitrogen bases , such as , uracil and theophllin following a multi step scheme starting from diacetone golucose (1) (scheme 1) .The prepared compound were identified by spectroscopic methods ; ir , mass , 1H and 13C nmr.

View Publication Preview PDF
Crossref
Publication Date
Wed Feb 12 2025
Journal Name
Jornal Brasileiro De Patologia E Medicina Laboratorial
Synthesis, Characterization, and Potential Biomedical Applications of Novel Symmetrical Liquid Crystal Mesogens
...Show More Authors

Background: The synthesis and characterization of novel liquid crystalline compounds have garnered signi|cant attention due to their potential applications in biomedical sciences, including drug delivery systems, biosensing, and diagnostic tools. This study focuses on synthesizing and characterizing new thiazolothiadiazole-based liquid crystals and evaluating their mesophase properties. Methods: A series of novel compounds containing 5H-thiazolo[4,3−b][1,3,4] thiadiazole units were synthesized via multi-step chemical reactions. The synthesis involved the reaction of chloroethyl acetate with 4−hydroxybenzaldehyde to yield an aldehyde intermediate, followed by subsequent transformations using hydrazine hydrate, ethylacetoacetate, and 1,2

... Show More
Publication Date
Wed Jul 01 2020
Journal Name
International Journal Of Pharmaceutical Research
Synthesis of Liquid Crystal Mesogenes Derived From Isophthalic Acid and Terephthalic Acid
...Show More Authors

Two series of bent and liner core mesogen containing 1,2,4-traizole ring [VI]a,g and series were synthesized by many steps starting from esterification of isophthalic acid and terephathalic acid with methanol to yield diester compound [I]a,b which was converted to their acid hydrazide [II]a,b and the acid hydrazide reacted with ammonium thiocyanate or diester reacted with thiosemicarbazide to yield compounds [III]a,b. Then cyclization by 4% NaOH to yielded 1,2,4 traizole-3- thiol compounds [IV]a,b , afterword adding hydrazine hydrate to yield compounds [V]a,b. These compounds condensated with different substituted aldehyde to give new Schiff bases[VI]a,b ,[VII]a,b . Also , reaction acid hydrazide [II]a,b with aldehyde [VII] to yielded Schif

... Show More
Scopus (1)
Scopus
Publication Date
Thu Jul 02 2020
Journal Name
International Journal Of Pharmaceutical Research
Synthesis of Liquid Crystal Mesogenes Derived From Isophthalic Acid and Terephthalic Acid
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Energy Procedia
Improved thermal and mechanical properties of CdBa2-x SrxCa2Cu3O8+δ superconducting compounds
...Show More Authors

View Publication
Scopus Clarivate Crossref