Org Lett 2016 Jan 29;18(2):244-7. Epub 2015 Dec 29.
Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China , Qingdao 266003, People's Republic of China.
Neosartoryadins A (1) and B (2), both with a unique 6/6/6/5 quinazoline ring system connected directly to a 6/5/5 imidazoindolone ring, together with three biogenetically related compounds 3-5, were isolated from the endophytic fungus Neosartorya udagawae HDN13-313. The absolute configurations of new compounds 1-4 were established. Compounds 1 and 2 displayed anti-influenza virus A (H1N1) activities with IC50 values of 66 and 58 μM, respectively (ribavirin as positive control, IC50 = 94 μM).