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

Synthesis of novel derivatives of 4-Pyridine carboxylic acid hydrazide and their activity on central nervous system

Six novel derivatives [2-7] of 4-Pyridine carboxylic acid hydrazide [PCH] were synthesized by treating this lead molecule with substituted arylsulphonyl and benzoyl chlorides

The molecular structures of the newly derived products were characterized by the help of UV Visible, IR, FAB, 1HNMR spectroscopy and CHN analysis

During the preliminary pharmacological screening, it was observed that the synthesized compounds induced noticeable changes on motor activity of the animals

Interesting structure activity relationship was also observed among the synthesized molecules. Because of the interesting affect on motor activity, the newly synthesized derivatives can further be evaluated for their effects on CNS