The following figure shows Ligand-receptor interactions of lead compound with IC50 in micromolar range. All of the following is/are possible suggestions to improve its potency except: Select one or more: Add double bond between D and E in Cis configuration Remove amine from position C since it is highly hydrophilic with high dehydration cost Add double bond between D and E in trans configuration Remove bromine atom from position B since it is a large atom and can cause steric clash in the binding site Add hydroxyl group at position A