Author/Authors :
Zafar, Shaista University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan , Akhtar, Shamim University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan , Tariq, Talat Federal Urdu University of Science and Technology - Department of Chemistry, Pakistan , Mushtaq, Noushin University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan , Akram, Arfa Federal Urdu University of Science and Technology - Department of Pharmaceutical Chemistry, Pakistan , Ahmed, Ahsaan University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan , Arif, Muhammad University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan , Naeem, Sabahat University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan , Anwar, Sana University of Karachi - Faculty of Pharmacy - Department of Pharmaceutical Chemistry, Pakistan
Abstract :
Dissociation constant (pKa) of ten novel phenacyl derivatives of piperidine were determined by potentiometric titration method in aqueous medium at room temperature (25 ±0.5°C). The sample solutions were prepared in deionized water with ionic strength 0.01M and titrated with 0.1M NaOH solution. In addition, ΔG 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.
Keywords :
Dissociation constant , phenacyl derivatives , CNS active agents , potentiometry , lipophilicity , pH partition theory.
