C. Schwartner et al., MARCHANTINS AND RELATED POLYPHENOLS FROM LIVERWORT - PHYSICOCHEMICAL STUDIES OF THEIR RADICAL-SCAVENGING PROPERTIES, Free radical biology & medicine, 20(2), 1996, pp. 237-244
Structurally unique macrocyclic phenols from liverwort, i.e., marchant
ins and related substances, were studied for their antioxidative poten
tial using pulse-radiolytic and EPR-spectroscopic techniques. The gene
rally diffusion-controlled rate constants for scavenging of azide radi
cals as a model electrophilic species and the sufficiently slow bimole
cular decay confirm their antioxidative potential. Transient spectra a
fter pulse radiolysis and the EPR spectra both demonstrate the interna
l strain of the macrocyclic ring. One compound, Perrottetin D, further
more gave proof to the hitherto only kinetically verifyable superior r
adical-scavenging capability of the aroxyl radical derived from a phen
olic antioxidant.