Antioxidant activity of several classes of lichen metabolites were assessed in the in vitro superoxide radical (SOR), nitric oxide radical and 2,2-diphenyl-1-picrylhydrazil radical scavenging assays. The despsides sekikaic acid and lecanoric acid showed promising antioxidant activity in SOR assay with IC₅₀ values of 82.0 ± 0.3 µmol and 91.5 ± 2.1 µmol, respectively, while the depsidone lobaric acid exhibited an IC₅₀ value of 97.9 ± 1.6 µmol, all relative to the standard, propyl gallate (IC₅₀ = 106.0 ± 1.7 µmol). One of the most abundant mononuclear phenolic compounds, methyl-β-orcinol carboxylate was found to be a potent NO scavenger (IC₅₀ = 84.7 ± 0.1 µmol), compared to the standard rutin (IC₅₀ = 86.8 ± 1.9 µmol).

A new high-load, soluble oligomeric dichlorotriazine (ODCT) reagent derived from ring-opening metathesis polymerization (ROMP) is reported as an effective coupling reagent, scavenger of nucleophilic species and activator of DMSO for the classic Swern oxidations. Two variants of this reagent 2GODCT 4 and 1GODCT 16, possessing theoretical loads of 5.3 mmol/g and 7.3 mmol/g, respectively, have been synthesized. Preparation was accomplished via simple synthetic protocols affording free flowing powders, amenable for large-scale production. Removal of the spent oligomeric reagent was achieved via either precipitation of the spent reagent or simple filtration utilizing a silica SPE, followed by solvent removal, to deliver products in excellent yield and purity. In addition, the corresponding norbornenyl monomer 3 was successfully demonstrated in a couple-ROMP-filter protocol utilizing in-situ polymerization, achieving comparable results versus the corresponding oligomeric variant.

The development of a ring-opening metathesis/ring-closing metathesis/cross metathesis (ROM-RCM-CM) cascade strategy to the synthesis of a diverse collection of bi-and tricyclic sultams is reported. In this study, functionalized sultam scaffolds derived from intramolecular Diels-Alder (IMDA) reactions undergo metathesis cascades to yield a collection tricyclic sultams. Additional appendage based diversity was achieved by utilizing a variety of CM partners.

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