Antioxidant CPA-type indole alkaloids produced from the deep-sea derived fungusAspergillussp. SCSIO 41024

Twelve indole alkaloids, including alpha-cyclopiazonic acid (CPA) (1), nine 2-oxo indole CPA derivatives (2-10), and two open-ring indole CPA derivatives (11and12), were isolated from the fermentation broth of a deep-sea derived fungusAspergillussp. SCSIO 41024. Their structures and absolute configurations were elucidated mainly by using extensive NMR spectroscopic, mass spectrometric and single crystal X-ray diffraction analysis. To the best of our knowledge, the crystallographic data of3and7were firstly reported, and the absolute configuration of3was confirmed for the first time by the single crystal X-ray diffraction analysis. Most isolated compounds were tested for their antimicrobial, antitumor and radical scavenging activities. In addition, compounds1,2and11showed moderate antioxidative activity against DPPH with IC(50)values of 190.1, 31.9, 228.4 mu g/mL, respectively.