HDAC6 and B-cell chronic lymphocytic leukemia: ■Pyrimidinecarboxylic acid;■Investigational for breast carcinoma (phase 1), chronic lymphocytic leukemia (phase 1), diabetic neuropathy (phase 2), multiple myeloma (phase 1), peripheral nervous system disease (phase 1), hilar cholangiocarcinoma (phase 1), and lymphoma (phase 1);■Histone deacetylase 6 (HDAC6) inhibitor.