In one aspect, the invention relates to 4-substituted benzoylpiperazine-1-substituted carbonyls having a structure represented by a formula: derivatives thereof, and related compounds; synthetic methods for making the compounds; pharmaceutical compositions comprising the compounds; and methods of treating disorders, e.g., various tumors and cancers, associated with β-catenin/BCL9 protein-protein interaction dysfunction using the compounds and compositions. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.