Development and validation of HPLC method for the determination of Candesartan in human plasma

Candesartan [CAN], an ARB-blocker, antihypertensive, was analyzed in human plasma by a simple, accurate and precise RP-HPLC [reverse phase-High performance liquid chromatography assay method which was then validated for its accuracy, specificity and precision. The mobile phase has a constitution of acetone, diethylamine and distilled water, while Phosphoric acid was used to adjust the pH to 2.5 +/- 0.1. This mobile phase was run at 1.1ml/min and the fluorescence wavelength was set to 392 nm. A C-18 HPLC, column particle size [5 [micro]m] Mediterranean Sea ® L x 1.D. 25cm x 4.6 mm [Supelcosil] , with auto sampler injection volume of 30[micro]l ,an internal standard Valsartan was utilized for chromatographic detection. Candesartan took a retention time of 6 +/- 0.5 minutes. This method was validated by the parameters of selectivity, accuracy, precision, repeatability, reproducibility, recovery, linearity and stability. Candesartan's calibration curves were found to be linear in the range of 200ng/ml to 3.125ng/ml and the coefficient of determination [r2] was found to be 0.99. Analytical recovery obtained was above 88%. Hence, this method has been found to be useful for determining Candesartan in plasma

Determination of pKa values of new phenacyl-piperidine derivatives by potentiometric titration method in aqueous medium at room temperature [25 +/- 0.5[degree sign]C]

Dissociation constant [pKa] of ten novel phenacyl derivatives of piperidine were determined by potentiometric titration method in aqueous medium at room temperature [25 +/- 0.5oC]. The sample solutions were prepared in deionized water with ionic strength 0.01M and titrated with 0.1M NaOH solution. In addition, DELTAG values were also calculated. Different prediction software programs were used to calculate pKa values too and compared to the experimentally observed pKa values. The experimental and theoretical values were found in close agreement. The results obtained in this research would help to predict the good absorption of the studied compounds and can be selected as lead molecules for the synthesis of CNS active agents because of their lipophilic nature especially compound VII

Behavioral and neurochemical profile of some novel phenacyl based isonipecotamide derivatives

Study of natural products led to the development of new molecules of potential biological activity. Piperidine nucleus constitutes one of the components of various alkaloids and drugs. During the course of our project regarding the synthesis of derivatives of piperidine carboxamide to study the effects of these compounds as anti-depressive agents, some of the compounds exhibited significant effects at all three doses, through open field activity thus establishing a direct relationship between dose and locomotion. Moreover, these compounds have also shown the decreased level of 5-HT alone with increased level of dopamine as an indication of their antagonism towards 5-HT receptor