All chemicals used were purchased from Aldrich Chemical Co., Ltd. (St. Louis, MO, USA), and were of highest commercially available purity. Silica gel for column chromatography (CC) was performed on silica gel (Merck silica gel 60H, particle size 5–40 μm) and Sephadex LH-20 gel. Thin layer chromatography (TLC) was performed on Merck aluminium backed plates, precoated with silica (0.2 mm, 60F254). UV spectra were recorded on Hitachi's U-2000 Double-Beam UV/Vis Spectrophotometer. Mass spectra were carried out on a Thermo Finnigan PolarisQ Ion Trap system (Waltham, MA, USA) using a direct exposure probe. Nuclear magnetic resonance 1H NMR and 13C NMR spectra were recorded at 400 and 100 MHz, respectively, on a Varian Gemini spectrometer (Palo Alto, CA, USA). Melting points were determined using a Stuart SMP10 melting point apparatus (Stone, Staffordshire, UK).
Diazepam was kindly donated by the Department of Pharmacy, University of Peshawar. Imipramine, DMSO, Tween solution (TWEEN® 80), flumazenil (Sigma-Aldrich, USA), and pentylenetetrazol (Tokyo Chemical Industries Co., Ltd.) were purchased for the study. All chemicals and solvents used in this research were of analytical grade.
Diazepam was kindly donated by the Department of Pharmacy, University of Peshawar. Imipramine, DMSO, Tween solution (TWEEN® 80), flumazenil (Sigma-Aldrich, USA), and pentylenetetrazol (Tokyo Chemical Industries Co., Ltd.) were purchased for the study. All chemicals and solvents used in this research were of analytical grade.