Ultrasonic Absorption Measurements of Propionic Acid Derivatives of NSAID and β-Cyclodextrin in Aqueous Solution

2016 ◽  
Vol 37 (6) ◽  
pp. 826-829 ◽  
Author(s):  
Jong-Rim Bae
Keyword(s):  
Aqueous Solution ◽  
Propionic Acid ◽  
Ultrasonic Absorption ◽  
Derivatives Of ◽  
Absorption Measurements

scholarly journals A Kinetic Study of the Monomer-dimer Reaction in Propionic Acid by Means of Ultrasonic Absorption Measurements

1972 ◽  
Vol 45 (10) ◽  
pp. 3096-3100 ◽  
Author(s):  
Nobuhide Tatsumoto ◽  
Takayuki Sano ◽  
Tatsuya Yasunaga
Keyword(s):  
Kinetic Study ◽  
Propionic Acid ◽  
Ultrasonic Absorption ◽  
Absorption Measurements

THE SYNTHESIS OF SOME DERIVATIVES OF 3,4-METHYLENEDIOXYBENZENE

1964 ◽  
Vol 42 (8) ◽  
pp. 1901-1905 ◽  
Author(s):  
Pritam Singh ◽  
Louis Berlinguet
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Acetic Anhydride ◽  
Hydrazine Hydrate ◽  
Propionic Acid ◽  
Sodium Acetate ◽  
Potassium Chlorate ◽  
Ammonium Formate ◽  
Dilute Aqueous Solution ◽  
Derivatives Of

A few derivatives of 3,4-methylenedioxy-α-nitromethylbenzyl alcohol (I) have been prepared. Chlorination with hydrochloric acid and potassium chlorate gave 6-chloro-3,4-methylenedioxy-α-nitromethylbenzyl alcohol (II) which on refluxing with acetic anhydride and sodium acetate gave 6-chloro-3,4-methylenedioxy-ω-nitrostyrene (III). Attempted reduction of (I) with ammonium formate resulted in dehydration to give 3,4-methylenedioxy-ω-nitrostyrene (IV). Reduction of (I) with hydrazine hydrate gave an isobenzaldoxime (VI).β-(3,4-Methylenedioxyphenyl) serine (VII) was prepared by the condensation of piperonal with glycine. α,β-Dibromo-β-(3,4-methylenedioxyphenyl) propionic acid could not be aminated by a dilute aqueous solution of ethylamine. Decarboxylation and elimination of HBr took place to give ω-bromo-3,4-methylenedioxystyrene (VIII).

scholarly journals Quantum-Chemical Search for Keto Tautomers of Azulenols in Vacuo and Aqueous Solution

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 497
Author(s):  
Ewa D. Raczyńska
Keyword(s):  
Aqueous Solution ◽  
Quantum Chemical ◽  
Biologically Active ◽  
Deprotonation Reaction ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Scanty Information ◽  
Derivatives Of ◽  
Common Anion ◽  
Tautomeric Mixture

Keto-enol prototropic conversions for carbonyl compounds and phenols have been extensively studied, and many interesting review articles and even books appeared in the last 50 years. Quite a different situation takes place for derivatives of biologically active azulene, for which only scanty information on this phenomenon can be found in the literature. In this work, quantum-chemical studies have been undertaken for symmetrically and unsymmetrically substituted azulenols (constitutional isomers of naphthols). Stabilities of two enol (OH) rotamers and all possible keto (CH) tautomers have been analyzed in the gas phase {DFT(B3LYP)/6-311+G(d,p)} and also in aqueous solution {PCM(water)//DFT(B3LYP)/6-311+G(d,p)}. Contrary to naphthols, for which the keto forms can be neglected, at least one keto isomer (C1H, C2H, and/or C3H) contributes significantly to the tautomeric mixture of each azulenol to a higher degree in vacuo (non-polar environment) than in water (polar amphoteric solvent). The highest amounts of the CH forms have been found for 2- and 5-hydroxyazulenes, and the smallest ones for 1- and 6-hydroxy derivatives. The keto tautomer(s), together with the enol rotamers, can also participate in deprotonation reaction leading to a common anion and influence its acid-base properties. The strongest acidity in vacuo exhibits 6-hydroxyazulene, and the weakest one displays 1-hydroxyazulene, but all azulenols are stronger acids than phenol and naphthols. Bond length alternation in all DFT-optimized structures has been measured using the harmonic oscillator model of electron delocalization (HOMED) index. Generally, the HOMED values decrease for the keto tautomers, particularly for the ring containing the labile proton. Even for the keto tautomers possessing energetic parameters close to those of the enol isomers, the HOMED indices are low. However, some kind of parallelism exists for the keto forms between their relative energies and HOMEDs estimated for the entire molecules.

scholarly journals Ultrasonic Absorption Mechanism in an Aqueous Solution of Isopropyl Alcohol

1976 ◽  
Vol 49 (5) ◽  
pp. 1413-1414 ◽  
Author(s):  
Sadakatsu Nishikawa ◽  
Mitsuo Mashima ◽  
Tatsuya Yasunaga
Keyword(s):  
Aqueous Solution ◽  
Isopropyl Alcohol ◽  
Ultrasonic Absorption ◽  
Absorption Mechanism

scholarly journals Molecular-Dynamics Simulations of C- and N-Terminal Peptide Derivatives of GCN4-p1 in Aqueous Solution

2005 ◽  
Vol 2 (8) ◽  
pp. 1086-1104 ◽  
Author(s):  
John H. Missimer ◽  
Michel O. Steinmetz ◽  
Wolfgang Jahnke ◽  
Fritz K. Winkler ◽  
Wilfred F. van Gunsteren ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Aqueous Solution ◽  
Molecular Dynamics Simulations ◽  
Peptide Derivatives ◽  
C And N ◽  
Dynamics Simulations ◽  
Derivatives Of

scholarly journals Radiolytic Oxidation of Peptide Derivatives of Glycine in Aqueous Solution

1972 ◽  
Vol 50 (1) ◽  
pp. 48 ◽  
Author(s):  
Hashim A. Makada ◽  
Warren M. Garrison
Keyword(s):  
Aqueous Solution ◽  
Peptide Derivatives ◽  
Radiolytic Oxidation ◽  
Derivatives Of

scholarly journals Ultrasonic absorption measurements in mammalian tissues

1978 ◽  
Vol 63 (S1) ◽  
pp. S13-S13
Author(s):  
S. A. Goss ◽  
L. A. Frizzell ◽  
F. Dunn
Keyword(s):  
Ultrasonic Absorption ◽  
Mammalian Tissues ◽  
Absorption Measurements

ChemInform Abstract: ULTRASONIC ABSORPTION MECHANISM IN AN AQUEOUS SOLUTION OF N-PROPYL ALCOHOL

1975 ◽  
Vol 6 (20) ◽  
Author(s):  
SADAKATSU NISHIKAWA ◽  
MITSUO MASHIMA ◽  
TATSUYA YASUNAGA
Keyword(s):  
Aqueous Solution ◽  
Ultrasonic Absorption ◽  
Absorption Mechanism ◽  
Propyl Alcohol

The Chemical Evolution of a Nitrogenase Model, 20 Alkyl Molybdates(VI) and the Mechanism of Hydrocarbon Production by Nitrogenase [1]

1982 ◽  
Vol 37 (3) ◽  
pp. 380-385 ◽  
Author(s):  
G. N. Schrauzer ◽  
Laura A. Hughes ◽  
Norman Strampach
Keyword(s):  
Aqueous Solution ◽  
Alkaline Hydrolysis ◽  
Room Temperature ◽  
Bond Cleavage ◽  
Model Compounds ◽  
Hydrocarbon Production ◽  
Acidic Solutions ◽  
Reducing Conditions ◽  
Hydrolysis Of ◽  
Derivatives Of

Abstract Colorless alkylmolybdates(VI) of composition R-MoO3-are generated in aqueous solutions by the alkaline hydrolysis of complexes R-Mo(Bpy)(0)2Br(Bpy = 2,2′-bipyridyl, R = CH3 and higher alkyl). At room temperature in alkaline aqueous solution, the new organometallic derivatives of oxomolybdate(VI) are remarkably resistant against Mo-C bond hydrolysis. Decomposition occurs more rapidly on heating, affording unrearranged alkanes according to the eq.: R-MoO3- + OH-→RH + Mo04=. In acidic solutions, the methylmolybdate(VI) species decomposes with the formation of a mixture of methane and ethane while higher alkylmolybdates carrying hydrogen in the β-position relative to molybdenum undergo Mo-C bond heterolysis by way of β-elimina-tion: R-CH2CH2-MoO3 → Mo+4 (aq) + H+ + R-CH = CH2. The Mo-C bond of alkylmolybdates is resistant to oxidants but is very sensitive to cleavage under reducing conditions. Reductive Mo-C bond cleavage occurs particularly rapidly in the presence of thiols and reduced ferredoxin model compounds. The latter reactions simulate the terminal steps of hydrocarbon producing reactions of nitrogenase with alternate substrates such as CN-, R-CN or R-NC, confirming previous mechanistic conclusions concerning the mechanism of nitrogenase action.

Toward novel sulphur-containing derivatives of tetraazacyclododecane: synthesis, acid–base properties, spectroscopic characterization, DFT calculations, and cadmium(ii) complex formation in aqueous solution

2020 ◽  
Vol 44 (20) ◽  
pp. 8337-8350 ◽  
Author(s):  
Marianna Tosato ◽  
Marco Verona ◽  
Riccardo Doro ◽  
Marco Dalla Tiezza ◽  
Laura Orian ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Complex Formation ◽  
Dft Calculations ◽  
Spectroscopic Characterization ◽  
Acid Base ◽  
Derivatives Of ◽  
Base Properties

New sulphur derivatives of cyclen, with potential complementary properties with respect to known compounds, have been synthesized and studied.

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