a
Department of Chemistry, Indian Institute of Technology Madras, Chennai, India
E-mail: sbhaskar@iitm.ac.in
;
Fax: (+91) 44-2257-0545
b
Department of Organic Chemistry, University of Yaounde 1, BP 812 Yaounde, Cameroon
c
Institute of Environmental Research and Analytical Chemistry, Dortmund University of Technology, 44227 Dortmund, Germany