Cytoprotective Polyketides from Sponge-Derived Fungus Lopadostoma pouzarii

Abstract

The new polyketides lopouzanones A and B, as well as the new 1-O-acetyl and 2-O-acetyl derivatives of dendrodochol B, were isolated from the sponge-derived marine fungus Lopadostoma pouzarii strain 168CLC-57.3. Moreover, six known polyketides, gliorosein, balticolid, dendrodolide G, dihydroisocoumarine, (–)-5-methylmellein, and dendrodochol B, were identified. The structures of the isolated compounds were determined by a combination of NMR and ESIMS techniques. The absolute configurations of the lopouzanones A and B were determined using the Mosher’s method. The cytotoxicity of the isolated compounds against human prostate cancer cells PC-3 and normal rat cardiomyocytes H9c2 was investigated. Gliorosein showed weak DPPH radical-scavenging activity and in vitro cardioprotective effects toward rotenone toxicity and CoCl2-mimic hypoxia.

Marine natural products

“…Total synthesis of each enantiomeric pair was achieved in nine steps. 204 Polyketides 594 and 595 and dendrodochol B derivatives 596 and 597 were isolated from a culture of Lopadostoma puzarii , 205 Metarhizium strains yielded a N -butenone spiroquinazoline alkaloid 598 , 206 macrolides 599 , 600 (as an equilibrating mixture of C-2 epimers), 601 and aromatic glycosides 602 and 603 , 207 and supplementation of a Monascus albidus culture with amino acids led to isolation of γ-lactams; enantiomers 604 / 605 and C-3 epimers 606 / 607 . 208 …”