1. The Graduate School, University of Santo Tomas, España Blvd., Manila 1015, Philippines
2. Laboratory for Organic
Reactivity, Discovery and Synthesis (Rm. 410), Research Center for the Natural and Applied Sciences, University of
Santo Tomas, Espana Blvd., Manila 1015, Philippines
3. Department of Chemistry, College of Science, Adamson University,
San Marcelino St., Ermita, Manila 1000, Philippines