A New Antimycobacterial, 3β-Acetoxy-15α,22-dihydroxyhopane, from the Insect Pathogenic Fungus Aschersonia tubulata

Abstract

Bioassay-guided fractionation of the cell extract of the insect pathogenic fungus Aschersonia tubulata BCC 1785 led to the isolation of dustanin (1), 3β,15α,22-trihydroxyhopane (3), 5α,8α-epidioxy-24(R)-methylcholesta-6,22-diene-3β-ol (6), together with the new 3β-acetoxy-15α,22-dihydroxyhopane (4). Chemical structures of these compounds were elucidated by spectral analyses as well as chemical transformation. Compounds 1 and 4 exhibited antimycobacterial activity with the minimum inhibitory concentration (MIC) of 12.5 μg/ml.

References

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