Isocoumarin Derivatives from the Sponge‐Associated Fungus Peyronellaea glomerata with Antioxidant Activities

Abstract

Chemical examination of the solid culture of the sponge-associated fungus Peyronellaea glomerata led to the isolation of five new isocoumarins, namely peyroisocoumarins A - D (1 - 4) and isocitreoisocoumarinol (5), together with 13 known analogues (6 - 18). Their structures were determined on the basis of extensive spectroscopic analyses, including the modified Mosher's method for the configurational assignments. Peyroisocoumarins A and B were characterized by the presence of Cl-atom at pentane chain, which were unusual in isocoumarin derivatives. The ARE reporter assay revealed that peyroisocoumarins A, B, and D exerted potent ARE activation in HepG2C8 cells, while the preliminary analyses of structure-activity relationship was discussed.

Naturally Occurring Isocoumarins Derivatives from Endophytic Fungi: Sources, Isolation, Structural Characterization, Biosynthesis, and Biological Activities

“…The ability of compounds72, 188, 189, 202-205, 207-211, 231, 233, 234, 286, and 287 to regulate Nrf2, that complies to the oxidative stress by binding to ARE in the gene's coding promoter for antioxidant enzymes and protein for the synthesis of glutathione using ARE-driven luciferase reporters in HepG2C8 cells was evaluated. Compounds 209, 210, and 233 (a dose 10 µM) produced a significant induction of luciferase 1.93-2.95 folds more than DMSO (blank control), whereas tBHQ (positive control) invigorated the luciferase activation with 4 folds more than DMSO at a dose (50 µM)[65].Compounds 80,88,118,119, 303, and 307 isolated from Penicillium coffeae were tested for their DPPH scavenging activities. Only 302 had a moderate effect (IC 50 656 µM), compared to BHT (IC 50 59 µM), whereas the rest compounds had no activities (IC 50 > 900 µM)[47].…”

New antimicrobial compounds produced by Seltsamia galinsogisoli sp. nov., isolated from Galinsoga parviflora as potential inhibitors of FtsZ

“…Additionally, the discovery metabolites of Seltsamia galinsogisoli sp.nov. resulted the isolation of seven known compounds ( 3–9 ), including 1,3-Benzenediol,5-(2-hydroxypropyl) ( 3 ) 27 , 3,4-Dihydroxy-2-methyl-7-[prop-1-enyl]-3,4-dihydro-2H-pyrano[4,3-b]pyran-5-one ( 4 ) 28–30 , 1H-2-Benzopyran-1-one,6,8-dihydroxy-3-(2-hydroxypropyl) ( 5 ) 31,32 , 2,5-dimethyl-7-hydroxyl chromone ( 6 ) 33 , 3-methyl-6,8-dihydroxyisocoumarin ( 7 ) 34 , Curvulapyrone ( 8 ) 34 , and 3,4-dihydro-8-hydroxyisocoumarin-3-carboxylic methyl ether ( 9 ) 35 .…”

Dihalohydration of Alkynols: A Versatile Approach to Diverse Halogenated Molecules

“…Using the same method, dichlorohydroxyketone 7n was converted into the corresponding syn ‐dichlorodiol 24 in 90 % yield. Interestingly, dibromo‐1,3‐diols such as 19 and 20 have never previously been synthesised (Scheme ) …”