Construction of Interconnected Acidity Functions Based on ortho Substituted Anilines and N-Methylanilines as Indicators

2001 ◽  
Vol 66 (11) ◽  
pp. 1638-1658 ◽  
Author(s):  
Oldřich Pytela ◽  
Jiří Kulhánek ◽  
Eva Jirásková ◽  
Taťjana Nevěčná
Keyword(s):  
Substituted Anilines ◽  
Acidity Functions ◽  
The Given ◽  
Derivatives Of

The log I values of 15 mainly ortho substituted derivatives of aniline and N-methylaniline have been measured spectrophotometrically in sulfuric, perchloric, and methanesulfonic acids. A new algorithm has been suggested for construction of acidity functions enabling simultaneous and independent construction of acidity functions in various media under the condition of equal values of pKa of the same indicators in the given media. The so-called interconnected acidity functions have been constructed with using this algorithm and the log I values measured in the above media, and the pKa values have been calculated. The resulting acidity functions and pKa values agree well with the corresponding literature data.

scholarly journals On Appel-Type Quadrature Rules

2002 ◽  
Vol 9 (3) ◽  
pp. 405-412
Author(s):  
C. Belingeri ◽  
B. Germano
Keyword(s):  
Remainder Term ◽  
Quadrature Rule ◽  
Bernoulli Numbers ◽  
Quadrature Rules ◽  
Rule Based ◽  
Numerical Example ◽  
The Given ◽  
Derivatives Of

Abstract The Radon technique is applied in order to recover a quadrature rule based on Appel polynomials and the so called Appel numbers. The relevant formula generalizes both the Euler-MacLaurin quadrature rule and a similar rule using Euler (instead of Bernoulli) numbers and even (instead of odd) derivatives of the given function at the endpoints of the considered interval. In the general case, the remainder term is expressed in terms of Appel numbers, and all derivatives appear. A numerical example is also included.

ChemInform Abstract: Investigation of the Reaction of N-Acetylindoxyl with Substituted Anilines. Synthesis of Derivatives of Indolo[3,2-b]quinolines.

ChemInform ◽  
2010 ◽  
Vol 33 (17) ◽  
pp. no-no
Author(s):  
N. Z. Tugusheva ◽  
S. Yu. Ryabova ◽  
N. P. Solov'eva ◽  
O. S. Anisimova ◽  
V. G. Granik
Keyword(s):  
Substituted Anilines ◽  
Derivatives Of

Acidity Dependence of the Tautomeric Equilibrium Between the First Conjugated Acids of 4-Aminoazobenzenes

1979 ◽  
Vol 32 (1) ◽  
pp. 41 ◽  
Author(s):  
S Yamamoto ◽  
Y Tenno ◽  
N Nishimura
Keyword(s):  
Sulfuric Acid ◽  
Tautomeric Equilibrium ◽  
Acid Solutions ◽  
Substituted Anilines ◽  
Aqueous Sulfuric Acid ◽  
Acidity Functions ◽  
Sulfuric Acid Solutions

Acidity functions based upon primary anilines which have no ortho substituents have been established in 20% ethanol-80% aqueous sulfuric acid solutions, and compared with those based upon o-substituted anilines and azobenzenes. It was found that the tautomeric equilibrium between azonium and anilinium forms in 4-aminoazobenzene derivatives invariably shifts to the azonium form with increase in acidity. This observation has been interpreted in terms of acidity functions.

Synthesis and Evaluation of Novel Fluorobenzimidazole Derivatives as Antibacterial and Antifungal Agents

2019 ◽  
Vol 4 (4) ◽  
pp. 209-215
Author(s):  
D. Joshi ◽  
R. Narigara ◽  
G. Jani ◽  
K. Parikh
Keyword(s):  
Bacterial Strains ◽  
Compound I ◽  
Substituted Anilines ◽  
Gram Negative ◽  
E Coli ◽  
New Class ◽  
Antibacterial And Antifungal ◽  
Derivatives Of ◽  
Multiple Step

A new class of fluorobenzimidazole derivatives (IIIa-j)was synthesized to investigate their antimicrobial potential. All the compounds were prepared by multiple step synthesis, initiating from the synthesis of 5-(difluoromethoxy)-1H-benzimidazole-2-thiol (I). The compound I was further reacted with different derivatives of 2-chloro-N-phenylacetamide (IIa-j) prepared by reacting differently substituted anilines with chloroacetylchloride and triethylamine in DMF (solvent); resulting in formation of fluorobenzimidazoles IIIa-j. The compounds IIIa-j were characterized by spectral analysis viz. 1H NMR, 13C NMR, mass spectra, elemental analysis and IR. All these compounds were screened in vitro for their antimicrobial activity against Gram-positive (S. aureus and E. faecalis) and Gram-negative bacterial (E. coli and P.aeruginosa) strains as well as fungi (A. niger and C. albicans). Some of the compounds exhibited promising results (in MIC) against Gram-negative bacterial strains.

scholarly journals Synthesis and Antimicrobial Evaluations of Sulfur Inserted Fluoro-Benzimidazoles

2021 ◽  
Vol 33 (7) ◽  
pp. 1525-1529
Author(s):  
Parmesh Kumar Dwivedi ◽  
Devdutt Chaturvedi
Keyword(s):  
Antimicrobial Agents ◽  
Bacterial Strains ◽  
Substituted Anilines ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
New Compounds ◽  
Derivatives Of ◽  
Multiple Step

A new series of fluorinated sulfur inserted benzimidazole analogues Za-i were synthesized and characterized. The new compounds were screened for their antimicrobial and antioxidant potential. The synthesized compounds were obtained by multiple step synthesis, initiating from the synthesis of 5-(difluoromethoxy)-1H-benzimidazole-2-thiol X. The compounds Ya-i prepared by reacting differently substituted anilines with chloroacetylchloride and triethylamine in DMF. Finally, the compound X was reacted with different derivatives of 2-chloro-N-phenylacetamide resulting in formation of titled compounds Za-i. The synthesized compounds (Za-Zi) were characterized by spectral analysis viz.1H & 13C NMR, mass spectra, elemental analysis and IR. The in vitro antimicrobial potential against Gram-positive (S. aureus and E. faecalis) and Gram-negative bacterial (E. coli and P.aeruginosa) strains as well as fungi (A. niger and C. albicans) was recorded for the obtained compounds. Some of the compounds exhibited encouraging results (in MIC) against Gram-positive and Gram-negative bacterial strains. These studies thus suggest that the designed sulfur inserted fluoro-benzimidazoles scaffold may serve as new promising template for further amplification as antimicrobial agents.

New possibilities of applications of the Barker quasi-lattice theory. Prediction of gE and hE of binary systems whose one component is formed by n-alkanes

1979 ◽  
Vol 44 (6) ◽  
pp. 1698-1714 ◽  
Author(s):  
Vladimír Dohnal ◽  
Robert Holub ◽  
Jiří Pick
Keyword(s):  
Aromatic Hydrocarbons ◽  
Lattice Theory ◽  
Binary Systems ◽  
Derived Relations ◽  
Orientation Effects ◽  
The Given ◽  
Derivatives Of ◽  
Arbitrary Component ◽  
Excess Quantities ◽  
Good Agreement

For binary systems of the type an arbitrary component + n-alkane we derived relations, on the basis of the Barker theory and on the basis of the group contribution concept, for predicting gE and hE from one system to another when the n-alkane length is changed. To carry out the prediction it is not necessary to evaluate any adjustable parameters. The developed method was tested using a large number of different systems covering alcohols, amines, ketones, esters, chlorinated derivatives of hydrocarbons, aromatic hydrocarbons and n-alkanes from n-pentane to n-hexadecane. The results of predictions are in very good agreement with experimental data in the cases, when the n-alkanes involved are not longer than n-decane. Systematic regular deviations in hE in the cases, when at least one of n-alkanes involved is longer, can be explained by the presence of orientation effects in the pure longer n-alkanes. The correction suggested by us for these effects improves considerably results obtained. The developed method appears to be suitable for the systematic prediction of excess quantities of systems of the given type and represents an effective test of the Barker theory.

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