Antibiotic. Protein tyrosine kinase inhibitor. Has antifungal, antimalarial, antiangiogenic (in vivo), anti-inflammatory and antiviral activity. Cyclooxygenase-2 (COX-2) expression inhibitor without affecting COX-1 expression in LPS-stimulated macrophages. Induces the differentiation of HL-60 cells into macrophages. Potent HSP90 inhibitor. Anticancer compound. In vivo Rad/Raf interaction inhibitor. Inhibitor of AP-1-, NF-kappaB- and serum response factor (SRF)-mediated transcription. Suppresses expression of iNOS (NOS II). Non-competitive inhibitor of ATP citrate lyase. DNA topoisomerase VI and type II DNA topoisomerase inhibitor. Protects against LPS/IFN-gamma-induced neuronal cell death. Apoptosis inducer.