“…Thus, in the past fewdecades we have studied rearrangements [ 1 , 2 , 3 , 4 ], heterocyclicring-openings [ 5 , 6 , 7 , 8 , 9 ], and the different behaviors [ 10 , 11 , 12 ] of many heterocyclic compounds, also gaininguseful information on their pharmacological activities (cardiovascular [ 13 , 14 , 15 ], antitumor [ 16 , 17 , 18 ], and anti-MDR1 [ 19 , 20 ] effectshave been evaluated).…”