1. Department of Chemistry, Faculty of Basic Sciences, University of Birjand, P. O. Box 97175-615, Birjand, Iran
2. Institut für Organische Chemie, Universität Regensburg, Universitätsstr. 31, 93053 Regensburg, German
3. Department of Chemistry, Faculty of Basic Sciences, Hakim Sabzevari University, P. O. Box 96179-76487, Sabzevar, Iran