This research is to test a new medicine called BMF-219. BMF-219 is a *covalent menin inhibitor*, which means it attaches to a protein called menin and stops it from working. This study is for adults with certain types of blood cancers like acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), diffuse large B-cell lymphoma (DLBCL), multiple myeloma (MM), and chronic lymphocytic lymphoma (CLL)/small lymphocytic lymphoma (SLL). The study will figure out the best dose and see how well BMF-219 works. **Key Points:** - **Length and Visits**: The study has different groups and may involve multiple visits. - **Eligibility**: Participants must be adults (18+), have specific blood cancer, and have tried other treatments without success. - **Risks and Precautions**: Participants need to have healthy organs, use birth control, and cannot join if they have certain diseases or infections. This is a Phase 1 trial, meaning it's the first time this drug is tested in humans, so safety is a priority. Participants should discuss potential benefits and risks with their doctor.