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A series of biologically active seven 2r, 4c-diaryl-3-azabicyclo[3.3.1]nonan-9-one-4-aminobenzoyl hydrazone derivatives have been synthesized in good yield. The structures of compounds have been established on the basis of IR, 1 H, 13 C NMR, and elemental analysis. The structure-activity relationships (SAR) have been studied by screening of antimicrobial activity over a representative panel of bacterial and fungal strains using two-fold serial dilution method. All these synthesized compounds exhibited significant activities against all bacterial and fungal strains.

Kinetics of oxidation of twenty six S-arylmercaptoacetic acids (SAMA) (I) by sodium perborate (PB) have been studied in acid medium. The product of oxidation is the corresponding thiophenol. The rate data of meta-and para-substituted acids have been correlated with DSP equations. While the para-compounds correlate well with PI and o;I values, the meta-compounds correlate well with PI and u; values. The reaction constants are negative and of smaller magnitudes. Further, the ortho-substituted acids show a good correlation with a triparametric equation involving Taft's PI and CT; and Charton's steric parameter v. There is a considerable steric contribution to the total ortho-substituent effect. Based on these observations, mechanism involving the formation of protonated arylsulfinylacetic acid intermediate, followed by an intramolecular rearrangement leading to the product thiophenol has been proposed. 0 1995 John Wiley & Sons, Inc.

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Kinetics of oxidation of substituted benzaldehydes by 4-(dimethylamino)pyridinium chlorochromate (DMAPCC) in protic solvent system has been studied at 303 K. The product of oxidation has been identified as benzoic acid. A unit order dependence of the reaction with respect [DMAPCC] and [benzaldehyde] has been observed. The reaction has been found to be catalysed by H + ions. Decrease in the dielectric constant of the medium decreases the rate. To study the effect of structure reactivity relationships some para-substituted benzaldehydes were subjected to oxidation kinetics by DMAPCC at four different temperatures and thermodynamic parameters were calculated. The isokinetic plot and Exner plot shows that all the para-substituted benzaldehydes are oxidised by the same mechanism. The Hammett plot is linear with positive q value. From the observed kinetic results a suitable mechanism was proposed.

The kinetics of oxidation of benzyl alcohol (BzOH) by benzimidazolium fluorochromate (BIFC) has been studied in 50% aqueous acetic acid medium at 308 K. The reaction is first order with respect to [oxidant] and [benzyl alcohol]. The reaction is catalysed by hydrogen ions. The decrease in dielectric constant of the medium increases the rate of the reaction. Addition of sodium perchlorate increases the rate of the reaction appreciably. No polymerization with acrylonitrile. The reaction has been conducted at four different temperature and the activation parameters were calculated. From the observed kinetic results a suitable mechanism was proposed.