A New Antibacterial Diterpene with a Fused 6-5-6-6 Ring System, Trichodermanin I, Isolated from the Soil-Derived Fungus Trichoderma atroviride YD-13

One new diterpene with a fused 6-5-6-6 ring system, trichodermanin I (1), along with three known ones, wickerols A and B and trichodermanin F (2-4), were acquired from the extract of Trichoderma atroviride YD-13 isolated from soil. Their chemical structures were determined by interpretation of 1D/2D nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Compound 1 was evaluated for inhibiting the growth of four human pathogenic bacteria (Clostridium botulinum, Escherichia coli, Salmonella, and Staphylococcus aureus) and exhibited potential antibacterial activity against C. botulinum, E. coli, and S. aureus with MIC values of 8.0 mu g/mL, 32 mu g/mL, and 16 mu g/mL, respectively.