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QSPR study on pKa values of N-methoxy-polynitroaniline derivatives

100%

Beteringhe A.

Open Chemistry

2005

tom 3

nr 4

585-591

A QSPR study is presented for acidities of thirteen N-methoxy-polynitroaniline derivatives. Hammett σ values are known for meta and para substituents, and in the present study values are introduced for ortho-substituents in these N-methoxy-polynitroaniline derivatives. Hammett σ values for ortho-substituents in these N-methoxy-polynitroaniline derivatives were obtained by multiplying para values with 0.65.

Microwave assisted synthesis, spectral studies and antimicrobial activities of some 2′,4′-difluorophenyl chalcones

75%

Vijayakumar S. , Arulkumaran R. , Sundararajan R. , Sakthinathan S. P. , Suresh R. , Kamalakkannan D. , Ranganathan K. , Sathiyamoorthy K. , Mala V. , Vanangamudi G. , Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

2013

tom Vol. 9, iss. 1

68-86

Some 2′,4′-difluorophenyl chalcones have been synthesized under microwave irradiation using aldol condensation between 2,4-difluoroacetophenone and substituted benzaldehydes using catalytic amount of hydroxyapatite. The yields of the chalcones are more than 85 %. The purities of these synthesized chalcones were examined by their physical constants and spectroscopic data. The UV absorption maxima (λmax, nm), infrared stretches (ν, cm-1) of CO, fingerprint region of CHip/op, CH=CHop, C=Cop modes, NMR chemical shifts (δ, ppm) of vinyl proton, carbon and carbonyl carbons have been assigned and correlated with Hammett substituent constants, F and R parameters using single and multi-regression analysis. From the statistical analysis the effect of substituent on the above spectral frequencies can be discussed. The antimicrobial activities of these synthesized chalcones have been screened using Bauer-Kirby method.