A fungal mycotoxin that inhibits the histone lysine methyltransferase (HKMT) SU(VAR)3-9 (IC₅₀ = 0.8 μM). Inhibits other Lys9-specific HMTs, including G9a (IC₅₀ = 2.5 μM) and DIM5 (IC₅₀ = 3 μM). Selectivity for Lys9-HMTs is indicated by higher IC₅₀ values (>90 μM) for Lys20-specific PRSET7, Lys27-specific EZH2, and Lys4-specific SET7/9.