Precursor-Directed Biosynthesis of Talaroenamine Derivatives Using a Yellow River Wetland-Derived Penicillium malacosphaerulum

Precursor-directed biosynthesis was used to introduce selected aniline derivatives into the talaroenamine pathway, which had recently been defined from a Yellow River wetland-derived Penicillim malacosphaerulum HPU-J01. The known talaroenamine B (1) and six previously undescribed talaroenamine derivatives, talaroenamines F–K (2–7), were generated and structurally characterized. The aniline derivatives are introduced via nonenzymatic addition to the reactive intermediate cyclohexanedione. Compound 2 was active against Bacillus cereus with an MIC value of 0.85 μg/mL.