Absolute Configurations and Chitinase Inhibitions of Quinazoline-Containing Diketopiperazines from the Marine-Derived Fungus Penicillium polonicum.

ABSTRACT: Three new quinazoline-containing diketopiperazines, polonimides A-C (1-3), along with four analogues (4-7), were obtained from the marine-derived fungus Penicillium polonicum. Among them, 2 and 4, 3 and 5 were epimers, respectively, resulting the difficulty in the determination of their configurations. The configurations of 1-3 were determined by 1D nuclear overhauser effect (NOE), Marfey and electron circular dichroism (ECD) methods. Nuclear magnetic resonance (NMR) calculation with the combination of DP4plus probability method was used to distinguish the absolute configurations of C-3 in 3 and 5. All of 1-7 were tested for their chitinase inhibitory activity against OfHex1 and

SUBMITTER: Guo XC 

PROVIDER: S-EPMC7551877 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature