HF51116 is a potent antagonist of CXCR4. HF51116 strongly antagonizes SDF-1α-induced cell migration, calcium mobilization, and CXCR4 internalization. HF51116 inhibits HIV-1 infection via CXCR4. HF51116 has the potential for the research of HIV-1 infection , hematopoietic stem cell mobilization, and cancer metastasis.