New Pyrrolobenzoxazine Sesquiterpenoid Derivatives from the Fungus Talaromyces trachyspermus

Three new pyrrolobenzoxazine sesquiterpenoids, talatrachyoxazines A-C ( 1 - 3 ), together with fourteen known compounds ( 4 - 17 ), were isolated from the fungus Talaromyces trachyspermus EU23. Their structures were identified by spectroscopic evidence and mass spectrometry. The absolute configurations of 1 - 3 were determined by NOESY data and comparison of their calculated and experimental electronic circular dichroism (ECD) spectra. Compound 1 showed cytotoxic activity against HelaS3, KB, HT-29, MCF-7, and HepG2 cell lines with IC (50) values of 7, 11, 10, 12, and 10 mu M, respectively. Compounds 1 and 14 showed weak antibacterial activity against the gram-positive bacteria Bacillus cereus and Bacillus subtilis , while 1 - 3 and 14 showed weak antibacterial activity against the gram-negative bacterium Pseudomonas aeruginosa . In addition, compound 1 showed weak antibacterial activity against Escherichia coli .

Automated summary

Three new pyrrolobenzoxazine sesquiterpenoids, talatrachyoxazines A-C (1-3), were isolated from the fungus Talaromyces trachyspermus EU23, along with fourteen known compounds. Compound 1 showed cytotoxic activity against several cancer cell lines and weak antibacterial activity against both gram-positive and gram-negative bacteria. The structures and absolute configurations of the compounds were determined using spectroscopic evidence and mass spectrometry.