[1] Univ Peshawar, Inst Chem Sci, Peshawar 25120, Pakistan
[2] Abdul Wali Khan Univ, Dept Chem, Mardan, Pakistan
[3] PCSIR Labs Complex Peshawar NWFP, Peshawar, Pakistan
[4] Univ Saskatchewan, Dept Chem, Saskatoon, SK S7N 0W0, Canada
[5] Univ Karachi, HEJ Res Inst Chem, Int Ctr Chem & Biol Sci, Karachi 32, Pakistan
[6] Univ Malakand, Dept Chem, Chakdara, Pakistan