In immunoglobulin light chain amyloidosis (AL), the unique antibody light chain (LC) protein that is secreted by monoclonal plasma cells in each patient misfolds and/or aggregates, a process leading to organ degeneration. For treating AL patients, such as those with substantial cardiac involvement who have difficulty tolerating existing chemotherapy regimens, provided herein are small molecule compounds of Formula Ia, Formula Ib, and Formula II that are kinetic stabilizers of the native dimeric structure of full-length LCs, which compounds can slow or stop the amyloidogenicity cascade at its origin.