scholarly journals NMR and Mass Spectroscopic Studies on Catharine

1985 ◽  
Vol 40 (4) ◽  
pp. 543-545 ◽  
Author(s):  
◽  
Irshad Ali ◽  
M. Iqbal Chaudhary
Keyword(s):  
Room Temperature ◽  
Spectroscopic Studies ◽  
Temperature Dependent ◽  
Mass Spectral Fragmentation ◽  
Mass Spectral ◽  
H Nmr ◽  
Temperature Dependent Study ◽  
C Nmr

The 13C NMR of Catharine is reported. A temperature-dependent study of the 1H NMR of Catharine indicates that it exists as two conformers at room temperature. At higher temperatures, the distinction between the two conformers disappears with the higher rate of equilibration. The mass spectral fragmentation of Catharine as established by link scan measurements is also re­ported.

Triazolopyridine nucleosides. II. Glycosylations of 3-oxo-s-triazolo[4,3-a]pyridines with accompanying conversions into 2-oxo-s-triazolo[1,5-a]pyridine nucleosides

1977 ◽  
Vol 55 (5) ◽  
pp. 831-840 ◽  
Author(s):  
Brian Maurice Lynch ◽  
Suresh Chandra Sharma
Keyword(s):  
General Structure ◽  
Spectroscopic Properties ◽  
Mass Spectral Fragmentation ◽  
Mass Spectral ◽  
H Nmr ◽  
Pyridine Nitrogen ◽  
Methyl Derivatives ◽  
Fragmentation Patterns ◽  
Ribose Moiety ◽  
C Nmr

3-Oxo-s-triazolo[4,3-a]pyridine and various C-methyl derivatives (general structure 1) have been converted into the 2-β-D-ribofuranosyl species 2 and thence 4 via Friedel–Crafts catalyzed reaction with tetra-O-acetyl-β-D-ribofuranose, followed by deblocking. During the course of these reactions, rearrangements into the isomeric 3-β-D-ribofuranosyl-2-oxo-s-triazolo[1,5-a]-pyridines occur through ring-opening of the pyridine rings yielding species 3 and 5. The proportion of rearrangement products is dependent upon the position and number of the C-methyl substituents.Structural assignments for these compounds are based upon comparisons of spectroscopic properties (1H nmr, 13C nmr, uv) with model compounds from each isomeric series; structural assignments for these models are based on unequivocal mass-spectral fragmentation patterns. Unlike related triazolopyridine nucleosides with the ribose moiety attached to a pyridine nitrogen (Lynch and Sharma (1976)), there are no unusual aspects in the conformations of the nueleosides of types 4 and 5.

Photochemistry of halogenated benzene derivatives. Part VIII. Photoformation of 2-methyl-4,5,6,7-tetrachlorobenzoxazole from pentachlorophenol in water–acetonitrile

1987 ◽  
Vol 65 (9) ◽  
pp. 2223-2233 ◽  
Author(s):  
Ghulam Ghaus Choudhry ◽  
Norma Jean Graham ◽  
G. R. Barrie Webster
Keyword(s):  
Nmr Spectroscopy ◽  
Chemical Yield ◽  
Polarization Transfer ◽  
Benzene Derivatives ◽  
Mass Spectral Fragmentation ◽  
Molecular Ion ◽  
Mass Spectral ◽  
Methanolic Solution ◽  
H Nmr ◽  
C Nmr

Photolysis of a solution of pentachlorophenol (1) in H2O–CH3CN (2:3 v/v) was conducted on a synthetic scale using wavelengths ≥290 nm. After changing the pH of the photolyzate of 1 to ≥12, the photoproduct 2-methyl-4,5,6,7-tetrachloro-benzoxazole (2) was extracted with n-hexane. The product 2 was crystallized from methanolic solution. Ultraviolet, IR, FT-1H-NMR, proton-decoupled normal FT-13C-NMR, and proton-decoupled DEPT (distortionless enhancement by polarization transfer) sequence FT-13C-NMR spectroscopy were used to identify photoproduct 2 as 2-methyl-4,5,6,7-tetrachlorobenzoxazole. A mechanism for the photoformation of benzoxazole 2 from 1 is proposed. 3,4,5,6-Tetrachlorocyclohexa-3,5-diene-1,2-ketocarbene formed from 2-hydroxy-3,4,5,6-tetrachlorophenyl radical is suggested as key intermediate involved in the generation of oxazole 2 from phenol 1. The chemical yield of 2 on the basis of 1 was ca. 1%. A mechanism is proposed to explain the mass spectral fragmentation of 2 via the losses of Ċl,:C=O, Cl—Ċ=O, CH3—Ċ=O, CH3CN, and C3H3ClNO species from the parent molecular ion.

scholarly journals An Efficient and Clean Synthesis of Thiophenyl Thiazole Depended Novel Triazolo[4,3-a]Quinoxaline Derivatives

2015 ◽  
Vol 51 ◽  
pp. 125-134
Author(s):  
Haresh G. Kathrotiya ◽  
Sagar P. Gami ◽  
Yogesh T. Naliapara
Keyword(s):  
Schiff Base ◽  
Elemental Analysis ◽  
Room Temperature ◽  
Mass Spectral Data ◽  
Mass Spectral ◽  
H Nmr ◽  
Clean Synthesis ◽  
Quinoxaline Derivatives ◽  
Ft Ir ◽  
C Nmr

A simple and efficient approach for the synthesis of thiophenyl thiazole based triazolo [4,3-a] quinoxaline derivatives is described. In this methodology, 3-hydrazinyl-N-(4-(thiophen-2-yl) thiazol-2-yl) quinoxalin-2-amine derivatives treated with various aromatic aldehyde to form Schiff base which on treatment with iodobenzene diacetate in dichloromethane at room temperature to furnish title compounds. The synthesized compounds were characterized by 1H NMR, 13C NMR, FT-IR, elemental analysis, and mass spectral data

scholarly journals New Method for Nucleophilic Substitution on Hexachlorocyclotriphosphazene by Allylamine Using an Algerian Proton Exchanged Montmorillonite Clay (Maghnite-H+) as a Green Solid Catalyst

2016 ◽  
Vol 11 (2) ◽  
pp. 151 ◽  
Author(s):  
Lahouaria Medjdoub ◽  
Belbachir Mohammed
Keyword(s):  
Nucleophilic Substitution ◽  
Room Temperature ◽  
Montmorillonite Clay ◽  
New Method ◽  
Solid Catalyst ◽  
H Nmr ◽  
Flight Mass Spectrometry ◽  
Crystalline Product ◽  
First Time ◽  
C Nmr

<p>Nucleophilic substitution on hexachlorocyclotriphosphazene (HCCTP) with allylamine in order to give hexa(allylamino)cyclotriphosphazene (HACTP)  is performed for the first time under mild conditions by using diethylether as solvent to replace benzene which is very toxic. The reaction time is reduced to half and also performed at room temperature but especially in the presence of an eco-catalyst called Maghnite-H<sup>+</sup>. This catalyst has a significant role in the industrial scale. In fact, the use of Maghnite is preferred for its many advantages: a very low purchase price compared to other catalysts, the easy removal of the reaction mixture. Then, Maghnite-H<sup>+</sup> is became an excellent catalyst for many chemical reactions. The structure of HACTP synthesized in the presence of Maghnite-H<sup>+</sup> to 5% by weight is confirmed by <sup>1</sup>H-NMR, <sup>13</sup>C-NMR, <sup>31</sup>P-NMR (Nuclear magnetic resonance) and FTIR (Fourier Transform Infrared spectroscopy). MALDI-TOF (Matrix-Assisted Laser Desorption/Ionisation-time-of-flight mass spectrometry) is used to establish the molecular weight of HACTP which is 471 g/mol. DSC (Differential Scanning Calorimetery) and TGA (Thermogravimetric Analysis) show that HACTP is a crystalline product with a melting point of 88 °C. It is reactive after melting but is degraded from 230 °C. Copyright © 2016 BCREC GROUP. All rights reserved</p><p><em>Received: 28<sup>th</sup> September 2015; Revised: 5<sup>th</sup> December 2015; Accepted: 4<sup>th</sup> January 2016</em></p><p><strong>How to Cite</strong>: Medjdoub, L., Mohammed, B. (2016). New Method for Nucleophilic Substitution on Hexachlorocyclotriphosphazene by Allylamine Using an Algerian Proton Exchanged Montmorillonite Clay (Maghnite-H+) as a Green Solid Catalyst. <em>Bulletin of Chemical Reaction Engineering &amp; Catalysis</em>, 11 (2): 151-160 (doi:10.9767/bcrec.11.2.541.151-160)</p><p><strong>Permalink/DOI:</strong> http://dx.doi.org/10.9767/bcrec.11.2.541.151-160</p>

Synthesis and Pharmacological Activities of Some New 2-[1-Heptyl-3-(4- methoxybenzyl)-5-oxo-1,5-dihydro-4H-1,2,4-triazol-4-yl]acetohydrazide Derivatives

2014 ◽  
Vol 69 (9-10) ◽  
pp. 969-981 ◽  
Author(s):  
Olcay Bekircan ◽  
Emre Mentese ◽  
Serdar Ulker
Keyword(s):  
Nmr Spectroscopy ◽  
Elemental Analysis ◽  
Lipase Activity ◽  
Spectral Studies ◽  
Antituberculosis Activity ◽  
Pharmacological Activities ◽  
Mass Spectral ◽  
H Nmr ◽  
Acetohydrazide Derivative ◽  
C Nmr

Abstract In the present investigation, the key intermediate acetohydrazide derivative 5 was synthesized starting from 3-(4-methoxybenzyl)-4-amino-4,5-dihydro-1,2,4-triazol-5-one (1) by a four-step reaction. Thiosemicarbazides 6a-f and arylidenehydrazide derivatives 8a-d were obtained from compound 5. The cyclization of compounds 6a-f in the presence of NaOH resulted in the formation of compounds 7a-f. The compounds were characterized by IR, 1H NMR, 13C NMR spectroscopy, elemental analysis and mass spectral studies. The compounds were tested for their anti-lipase, anti-α-glucosidase and anti-mycobacterial activities. Compounds 6b and 8c exhibited excellent anti-lipase activity, and compound 8d showed excellent anti-a-glucosidase activity. Compounds 3 and 4 exhibited good antituberculosis activity

Synthesis of isothiocyanates from non-aromatic nitrogen-containing heterocycles

1986 ◽  
Vol 51 (1) ◽  
pp. 112-117 ◽  
Author(s):  
Jozef Gonda ◽  
Pavol Kristian ◽  
Ľubomír Mikler
Keyword(s):  
Spectral Methods ◽  
Mass Spectral ◽  
H Nmr ◽  
C Nmr

Investigation of the reaction of thiophosgene with Δ2-oxazolines I, Δ3-thiazolines II, 4H-benzo[d][1,3]thiazines III, 2-methoxypentahydro-Δ1-azepine IV, theophylline and caffeine showed that only compounds I and IV reacted to give 2-acyloxyethyl isothiocyanates and methyl 6-isothiocyanatohexanoate. The structure of these products was corroborated by IR, 1H NMR, 13C NMR and mass spectral methods. The suitability of the above-mentioned compounds to react is discussed.

Metall-π-Komplexe yon Benzolderivaten, XIII Bis(methylthio-η-beiizol)chrom(0) Darstellung und Einsatz als zweizähniger Chelatligand/ Metal-π Complexes of Benzene Derivatives, XIII Bis(methylthio-η-benzene)chromium(0) Preparation and Function as a Bidentate Chelating Ligand

1981 ◽  
Vol 36 (1) ◽  
pp. 94-101 ◽  
Author(s):  
Helmut Burdorf ◽  
Christoph Eischenbroich
Keyword(s):  
Nmr Spectra ◽  
Room Temperature ◽  
Radical Cations ◽  
Esr Spectra ◽  
Benzene Derivatives ◽  
Consecutive Reaction ◽  
H Nmr ◽  
Chelating Ligand ◽  
And Function ◽  
C Nmr

Abstract The thioanisole-π-complexes (methylthio-η-benzene)-(η-benzene)-chromium (2) and bis(methylthio-η-benzene)chromium (3) have been prepared via lithiation of bis(η-benzene)-chromium and consecutive reaction with dimethyldisulfide. 1H NMR and 13C NMR spectra of 2 and 3 as well as ESR-spectra of the corresponding radical cations 2.+ and 3.+ were recorded and analyzed. In contrast to C(η-arene)-Si and C(η-arene)-P bonds, C(y-arene)-S bonds are stable to solvolysis. With (norbornadiene)tetracarbonylmolybdenum, 3 readily forms [bis(methylthio-η-benzene)chromium]tetracarbonylmolybdenum (6) wherein 3 functions as a chelating ligand. 1H and 13C NMR evidence suggests, that at room temperature 6 undergoes rapid conformational interconversions.

Synthesis and characterization of N-glucosylated dithiadiazepine derivatives through carbon-sulfur bond formation

2015 ◽  
Vol 21 (5) ◽  
pp. 269-272 ◽  
Author(s):  
Snehal A. Chavan ◽  
Avinash G. Ulhe ◽  
Baliram N. Berad
Keyword(s):  
Bond Formation ◽  
Synthesis And Characterization ◽  
Mass Spectral ◽  
H Nmr ◽  
Chemical Structures ◽  
Elemental Analyses ◽  
New Compounds ◽  
Sulfur Bond ◽  
C Nmr

AbstractNew 4,7-bis(arylamino)-2-tetra-O-acetyl-β-d-glucopyranosylimino-1,3,5,6-dithiadiazepines were synthesized via reaction of N-tetra-O-acetyl-β-d-glucopyranosyl isocyanodichloride with 1,6-diaryl-2,5-dithio-bis-ureas without using any catalyst. Thus, the synthesis of 7-membered heterocycles containing two sulfur and two nitrogen atoms through carbon-sulfur bond formation was explored. The chemical structures of these new compounds were elucidated by IR, 1H NMR, 13C NMR, mass spectral, and elemental analyses.

Minor diterpene components of the defense secretion from the frontal gland of soldiers of the species Nasutitermes costalis (HOLMGREN)

1984 ◽  
Vol 49 (9) ◽  
pp. 2024-2039 ◽  
Author(s):  
Irena Valterová ◽  
Miloš Buděšínský ◽  
František Tureček ◽  
Jan Vrkoč
Keyword(s):  
Acid Methyl Ester ◽  
Mass Spectral Fragmentation ◽  
Stable Conformation ◽  
Relative Configuration ◽  
Mass Spectral ◽  
Defense Secretion ◽  
Alternative Structures ◽  
H Nmr ◽  
Nasutitermes Costalis ◽  
Hydroxy Groups

Three minor components of the defense secretion from soldiers of the species Nasutermes costalis (HOLMGREN) have been isolated and characterized by means of spectral methods. The first component was identified as 1(15),8(19)-trinervitadien-9β-ol (III), known to occur with the subfamily Nasutitermitinae. For the second component two alternative structures IVa, IVb have been tentatively suggested, both with the 7,16-secotrinervitane skeleton. The third component was determined as 5β,9β-diacetoxy-2-oxo-11(12)kempen-20-oic acid (VII). The kempene skeleton was established on the basis of the 13C NMR spectrum and mass spectral fragmentation of the acid methyl ester. The relative configuration, together with a probable conformation of the tetracyclic framework were determined by 1H NMR. Two major tricyclic components, 1(15),8(19)-trinervitadien-2α,3β-diol (I) and 1(15),8(19)-trinervitadien-2α,3α-diol (II), were further characterized as mono and diacetates. Different rates of acetylation of the hydroxy groups in these diols provided evidence of stable conformation of the six-membered ring within the trinervitane skeleton.

scholarly journals Synthesis, Antioxidant, Antimicrobial, Antimycobacterial, and Cytotoxic Activities of Azetidinone and Thiazolidinone Moieties Linked to Indole Nucleus

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
A. R. Saundane ◽  
Prabhaker Walmik
Keyword(s):  
Spectral Studies ◽  
Cytotoxic Activities ◽  
Mass Spectral ◽  
H Nmr ◽  
Excellent Activity ◽  
C Nmr

2-N-(2-Phenyl-1H-indol-3-yl)imino-4-arylthiazoles (3a–c) were used as key synthons for the preparation of (4-arylthiazol-2-yl)-4-(2-phenyl-1H-indol-3-yl)azetidin-2-ones (4a–c) and 3-(4-arylthiazol-2-yl)-2-(2-phenyl-1H-indol-3-yl)thiazolidin-4-ones (5a–c). These newly synthesized compounds have been characterized with the help of IR,1H NMR,13C NMR, and mass spectral studies. All compounds were screened for their antioxidant, antimicrobial, antimycobacterial, and cytotoxic activities. Some of the compounds displayed excellent activity.

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