A Facile Synthesis and Reactions of Some Novel Pyrazole-based Heterocycles

2019 ◽  
Vol 16 (3) ◽  
pp. 405-412 ◽  
Author(s):  
Ahmed A.O. Abeed ◽  
Talaat I. El-Emary ◽  
Mohamed S.K. Youssef
Keyword(s):  
1H Nmr ◽  
High Performance ◽  
Nmr Spectra ◽  
Melting Points ◽  
Facile Synthesis ◽  
Direct Titration ◽  
Elemental Analyses ◽  
Ft Ir ◽  
Active Methylene ◽  
Pyrazoline Derivative

<p>Aim and Objective: This work presents the synthetic capability and the exploitation of 1,3-diphenyl- 1H-pyrazole-4-carboxladehyde 1 and 5-diphenyl pyrazolyl-2-pyrazoline analogue 8 to serve as excellent precursors for the synthesis of substituted indol-2,3-dione, trizolo[3,4-a]benzazoles, thiazolo[2,3- a]benzimidazole-3-one, substituted 2-pyrazoline and pyrazole-substituted-pyrazolines using various reagents. </P><P> Materials and Methods: Using chemicals from Aldrich, Fluka, or Merck, and pure solvents, we apply the synthetic procedures for the synthesis of novel heterocycles. The melting points of these compounds were determined using APP. Digital ST 15 melting point apparatus. SP3-100 spectrophotometer recorded FT-IR spectra (KBr) (cm-1). NMR spectra (&#948;, ppm) were recorded on 400 MHz AVANCE-III High-Performance FT-NMR Spectrometer BRUCKER (Switzerland) and some 1H NMR spectra were recorded on Varian EM-360L NMR Spectrophotometer (90 MHz) (USA) in CDCl3 or DMSO-d6 as a solvent. Elemental analyses were carried out at a Vario EL C, H, N, and S Analyzer. Bromine was determined using direct titration method after carius combustion. </P><P> Results: The structures of the compounds were confirmed by IR, 1H NMR, 13C NMR, and elemental analyses. </P><P> Conclusion: 1,3-Diphenyl-1H-pyrazole-4-carboxladehyde 1 and 2-pyrazoline derivative 9 confirmed their importance in the synthetic organic chemistry. Depending on the formyl group of aldehyde 1 and active methylene of pyrazoline 8, we synthesized new series of heterocycles; indol-2,3-dione, trizolo[3,4-a]benzazole, thiazolo[2,3-a]benzimidazole-3-one and pyrazolyl-pyrazoline derivatives expecting their pharmacological applications. The targeted compounds were substantiated from its spectral data.</p>

Efficient synthetic access to novel indolo[2,3-b]quinoxaline-based heterocycles

2021 ◽  
Vol 18 ◽  
Author(s):  
Ahmed Abdou O. Abeed ◽  
Talaat I. El-Emary ◽  
Sarah Alharthi
Keyword(s):  
Organic Chemistry ◽  
Mass Spectrometry ◽  
Heterocyclic Compounds ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Melting Points ◽  
Internal Reference ◽  
Elemental Analyses ◽  
Ft Ir ◽  
Synthetic Routes

Background: This paper showed the synthetic capability of the indolo[2,3-b]quinoxaline nucleus to be provided as an excellent precursor for the synthesis of various heterocyclic compounds. These synthetic routes proceed via the formation of 3-(6H-indolo[2,3-b]quinoxalin-6-yl)propane hydrazide (2). The carbohydrazide 2 and its reactions with different reagents give five and six-membered rings, such as 1,3,4-thiadiazole, 1,3,4-oxadiazole, 1,2,4-triazole, and 1,2,4-triazine. Methods: All chemicals used in the current study were of analytical grade. Melting points were determined using an APP Digital ST 15 melting point apparatus and were uncorrected. FT-IR spectra were recorded on a Pye-Unicam SP3-100 and Shimadzu-408 spectrophotometers in KBr pellets and given in (cm-1) KBr. The NMR spectra were detected by a Bruker AV-400 spectrometer (400 MHz for 1H, 100 MHz for 13C and 40.55 MHz for 15N), Institute of Organic Chemistry, Karlsruhe, Germany. Chemical shifts were expressed as δ (ppm) with TMS as an internal reference. Mass spectrometry was provided on a Varian MAT 312 instrument in EI mode (70 eV). Results: The target compounds were obtained, and their structures were completely elucidated by various spectral and elemental analyses (Ft-IR, 1H-NMR, 13C-NMR, and mass spectrometry). Conclusion: The current work showed a view of the reactivity of the carbohydrazide group. The carbohydrazide 2 was obtained from the hydrazinolysis of carboethoxy compound 1 and exploited as a key intermediate to synthesize heterocyclic compounds with different rings.

Synthesis and magnetic properties of polymeric complexes containing ruthenium(II)-ruthenium(III) tetracarboxylato units linked by cyanato, thiocyanato, and selenocyanato ligands

2008 ◽  
Vol 62 (4) ◽  
Author(s):  
Makoto Handa ◽  
Hideaki Ishida ◽  
Kayoko Ito ◽  
Toshihiro Adachi ◽  
Takahisa Ikeue ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Diffuse Reflectance ◽  
Magnetic Susceptibilities ◽  
Diffuse Reflectance Spectra ◽  
Main Species ◽  
Elemental Analyses ◽  
Polymeric Species ◽  
Polymeric Complexes

AbstractPolymeric complexes of ruthenium(II)-ruthenium(III) tetracarboxylato units linked by cyanato, thiocyanato, and selenocyanato ligands [Ru2{O2C(CH2)mCH3}4(L)]n (m = 0, 4–7; L = OCN−, SCN−, and SeCN−) were prepared and characterized based on the elemental analyses, IR, and diffuse reflectance spectra. Magnetic susceptibilities were measured at the temperature range of 4.5 K to 300 K, where the interdimer antiferromagnetic interactions were revealed. The strongest interaction was exhibited in case of m = 7 and L = OCN−. 1H-NMR spectra of [Ru{O2C(CH2)7CH3}4(SCN)]n in CD2Cl2 showed broad signals which can be ascribed to polymeric species, as the addition of tetrabutylammonium thiocyanate caused sharper signals due to the formation of [Ru2{O2C(CH2)7CH3}4(SCN)2]− adduct as the main species in the solution.

Synthesis of 5-Acetylacenaphthene Using Silica-Supported Phosphotungstic Heteropoly Acid as an Efficient and Reusable Catalyst

2012 ◽  
Vol 560-561 ◽  
pp. 214-220
Author(s):  
Ai Xia Pan ◽  
Yin Yin Wu ◽  
Yu Fang ◽  
Lu Lu Xu ◽  
Min Chen
Keyword(s):  
Catalytic Activity ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Benzoyl Chloride ◽  
Heteropoly Acid ◽  
Environmentally Benign ◽  
Reusable Catalyst ◽  
Acylation Reaction ◽  
Experimental Parameters ◽  
Ft Ir

To obtain new fine chemical and intermediate of functional polymer material, the acylation of acenaphthene with benzoyl chloride to 5-acetylacenaphthene catalyzed by silica-supported phosphotungstic heteropoly acid (PW/SiO2) was investigated. Pure 5-acetylacenaphthene was obtained and its structure was identified by GC/MS, FT-IR and 1H NMR spectra. The effects of experimental parameters on the catalytic acylation reaction and the possibility of reusability of PW/SiO2 catalyst were studied. Under optimun conditions, the yield and the selectivity of 5-acetylacenaphthene were up to 81.3 % and 93.6 %, respectively. PW/SiO2 shows well catalytic activity after running for 5 times. The experimental results indicate that PW/SiO2 is a recyclable and environmentally benign catalyst in the synthesis of 5-acetylacenaphthene.

Synthesis and Properties of a Novel Liquid Crystalline Monomer Containing Chalcone Moiety

2011 ◽  
Vol 380 ◽  
pp. 326-330 ◽  
Author(s):  
Ji Lei Li ◽  
Wei Min Zhang ◽  
Yu Lei Zhao ◽  
Jia Ling Pu
Keyword(s):  
Thermal Properties ◽  
Liquid Crystal ◽  
Optical Microscopy ◽  
1H Nmr ◽  
Nematic Phase ◽  
Nmr Spectra ◽  
Liquid Crystalline ◽  
Crystal Temperature ◽  
Polarized Optical Microscopy ◽  
Ft Ir

A kind of novel liquid crystalline monomer containing double photosensitive groups which were azo and chalcone groups was synthesized. The structures of the intermediates and the final monomer were confirmed by FT-IR and 1H NMR spectra. The thermal properties of monomer were measured by DSC and the liquid crystalline texture was measured by polarized optical microscopy. And the results indicated that the monomer showed nematic phase and liquid crystal temperature range was 150.8-186.5oC.

scholarly journals ISOLATION AND CHARACTERISATION OF RAPAMYCIN, TEMSIROLIMUS REGIO ISOMER (MONOESTER) AND TEMSIROLIMUS DIESTER IN TEMSIROLIMUS DRUG

2019 ◽  
pp. 94-99
Author(s):  
Gorla S. Reddy ◽  
Chava V. N. Rao
Keyword(s):  
Liquid Chromatography ◽  
1H Nmr ◽  
High Performance ◽  
Process Development ◽  
Uv Spectra ◽  
The Other ◽  
Esi Ms ◽  
Medium Pressure Liquid Chromatography ◽  
Photodiode Array ◽  
Ft Ir

Objective: Separation and identification of the process impurities in the manufacture of temsirolimus drug viz., rapamycin, temsirolimus regioisomer (monoester) (TS monoester), and temsirolimus diester (TS diester). Methods: During the process development of temsirolimus (TS), three process impurities-rapamycin, temsirolimus regioisomer (monoester) and temsirolimus diester-were detected by high-performance liquid chromatography (HPLC). Impurities were isolated by medium pressure liquid Chromatography (MPLC) and characterized by ESI-MS/MS, 1H NMR, FT-IR spectral data. Results: These impurities are characterised with the help of ESI MS/MS, 1H NMR, and FT-IR data. The impurities are identified and characterised as the process impurities. One of them is the starting material i.e. rapamycin and the other two are formed during the manufacture of the drug. This method offers advantages over using photodiode-array UV detection (LC-PDA) for the determination of peak purity, viz. components with similar UV spectra can be distinguished. Conclusion: The structures of these impurities were characterized as rapamycin, TS Monoester, and TS Diester. Out of these process impurities, rapamycin has been previously identified while the other two are previously unreported.

scholarly journals Synthesis of Some Heterocyclic Compounds Derived from 2-Mercapto Benzoxazole

2013 ◽  
Vol 10 (3) ◽  
pp. 766-778 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Acetic Acid ◽  
Melting Point ◽  
Heterocyclic Compounds ◽  
Nmr Spectra ◽  
Ring Closure ◽  
Phenyl Isothiocyanate ◽  
Triazole Derivative ◽  
Active Methylene Compounds ◽  
Ft Ir ◽  
Active Methylene

New series of 2-mecapto benzoxazole derivatives (1-20) incorporated into fused to different nitrogen and suphur containing heterocyclic were prepared from 2-meracpto benzoxazole, when treated with hydrazine hydrate to afford 2-hydrazino benzoxazol (1). Compound (1) converted to a variety of pyridazinone andphthalazinone derivatives (2-4) by reaction with different carboxylic anhydride. Also, reaction of (1) with phenyl isothiocyanate and ethyl chloro acetate afforded 3-phenyl-1,3-thiazolidin-2,4-dione-2-(benzoxazole-2-yl-hydrazone) (6). Azomethines (7-10) were prepared through reaction of (1) with aromatic aldehyde, then (7, 8) converted to thaizolidinone derivatives (11, 12). Treatment of (1) with active methylene compounds afforded derivative (13). Reaction of (1) with CS2 and NaOH gave 1,2,4-triazole derivative (14). Treatment of (1) with p-bromophenancyl bromide afforded another 1,2,4-triazole (15). The reaction of 2-mercapto benzoxazole with chloro acetic acid gave (16) followed by refluxing (16) with ortho-amino aniline giving benzimidazol (17). Moreover, the reaction of 2-mercapto benzoxazole with ethyl chloroacetate afforded (18), and then reaction of (18) with thiosemicarbazide and 4% NaOH leads to ring closure giving 1,2,4-triazole derivative (20). All compounds were confirmed by their melting point, FT-IR, UV-Vis spectra and 1H-NMR spectra for some of them.

scholarly journals BIOLOGICAL ACTIVE ACYLHYDRAZIDE I. THE O-ACYL-DERIVATIVES NATURE OF MONOACYLATION PRODUCTS OF CYCLIC MALEIC- AND PHTHALIC-HYDRAZIDE

1999 ◽  
Vol 7 (8) ◽  
pp. 25-40
Author(s):  
I Panea ◽  
Lucia Bodochi ◽  
Teodora Panea ◽  
Daniela Zinveliu ◽  
Violeta Pascalau
Keyword(s):  
1H Nmr ◽  
Nmr Spectra ◽  
1H Nmr Spectra ◽  
Melting Points ◽  
Derivatives Of ◽  
Acyl Derivatives

We confirmed, on the basis of chemical and physicochemical (melting points, IR- and 1H-NMR-spectra) data, that the products isolated by monoacylation of cyclic maleic- and phthalic-hydrazides have only the O-acyl derivatives nature although owing to tautomerism. These hydrazides may give rise to N- or/and O-acyl derivatives in such reactions. Simultaneously, we showed that the claims for the obtainment of N-acyl derivatives of cyclic maleic- and phthalic-hydrazides were not valid. Also by reacting the cyclic maleic-, respectively phthalic-hydrazide, with 4-chlorobenzoylchloride two new O-monoacylderivatives [3-( 4-chlorobenzoyloxy)-l-H-pyridazin-6-one and 1-(4-chlorobenzoyloxy)-3-H-phthalazin-l-one] were obtained

scholarly journals Synthesis , Characterization and Biological activity of new derivatives of Chromen-2-one

2018 ◽  
Vol 15 (1) ◽  
pp. 6130-6135
Author(s):  
Aziz Behrami
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Nmr Spectra ◽  
13C Nmr Spectra ◽  
Melting Points ◽  
Benzenesulfonyl Chloride ◽  
Bacterial Cultures ◽  
Escherchia Coli ◽  
Elemental Analyses ◽  
Derivatives Of

We report the organic syntheses of new derivatives  from Chromen-2-one and their  antibacterial activity. Compounds  4-[Acetyl-(2-oxo-2H-chromen-4-yl)-amino]- benzenesulfonyl chloride 1a, 4-[Acetyl-(2-oxo-3-phenylsulfamoyl-2H-chromen-4-yl)-amino]-benzenesulfonyl chloride 2a , 2-{4-[Acetyl-(4-chlorosulfonyl-phenyl)-amino]-2-oxo-3-phenylsulfamoyl-2H-chromen-7-ylamino}-benzoic acid  3a. All Structures have been synthesized and characterized using melting points , IR spectra , 1H-NMR, 13C-NMR spectra , and elemental analyses  . The purified synthesized compounds (1a,2a,3a), at contcentrations 2,3,5 mg/ml was tested for their  antibacterial activity against three bacterial cultures ;Staphylococcus aureus, Escherchia coli and Bacillus cereus. The antibacterial activity of synthesized compounds are compared with antibacterial activity of standard antibiotics cephalexine and streptomycine.   The compounds (1a,2a,3a) shows  different bacteriostatic and bacteriocidal activity.

scholarly journals CHARACTERISATION OF Fe(III), Co(II), Ni(II) AND Cu(II) COMPLEXES OF SALICYLSALICYCLICACID HYDRAZONE BY PHYSICO-CHEMICAL METHODS

2011 ◽  
Vol 08 (16) ◽  
pp. 6-16
Author(s):  
Srilalitha VINNAKOTA ◽  
Raghavendra Guru Prasad ALURU ◽  
Ramana Kumar KAKARLA ◽  
Seshagiri VAHI ◽  
RAO KRISHNA RAO Ravindranath LAXMAN
Keyword(s):  
Thermal Analysis ◽  
Metal Ions ◽  
1H Nmr ◽  
Magnetic Moment ◽  
Nmr Spectra ◽  
Molar Conductivity ◽  
1H Nmr Spectra ◽  
Chemical Methods ◽  
Physico Chemical ◽  
Elemental Analyses

The complexes of Fe(III), Co(II), Ni(II) and Cu(II) with salicylsalicyclicacid hydrazone (SSAH) were synthesized. The ligand and the complexes were characterized by elemental analyses, UV-Vis, IR and 1H NMR spectra, as well as by thermal analysis, molar conductivity and magnetic moment measurements. The tentative geometry of the complexes was proposed in each case and it was proposed that the metal ions under study form 1:1 complex with the ligand.

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