1. Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford, OX1 3TA, U.K.
2. Chemistry
Branch, Faculty of Petroleum and Mining Engineering, Suez University, Suez 43721, Egypt
3. Departamento
de Química Orgánica, Universidad de Salamanca, Plaza de
los Caídos 1−5, 37008 Salamanca, Spain
4. SUPA,
School of Physics and Astronomy, University of St Andrews, North
Haugh, St Andrews, KY16
9SS, U.K.