1. a Phytochemistry Research Laboratory, Department of Pharmaceutical Sciences , University of Strathclyde , SIBS Building, 27 Taylor Street, Glasgow, G4 ONR, UK
2. b Delass Natural Products, the Jordanian Pharmaceutical Manufacturing Company , Naor, P.O. Box 94, Jordan
3. c School of Biomedical Sciences, University of Ulster at Coleraine , Cromore Road, Coleraine, BT52 1SA, UK