Phenolic compounds are the main special metabolites of Cyperaceae species from phytochemical,
pharmacological, and chemotaxonomical points of view. The present study focused on
the isolation, structure determination, and pharmacological investigation of constituents
from Carex praecox. Twenty-six compounds, including lignans, stilbenes, flavonoids,
megastigmanes, chromenes, and phenylpropanoids, were identified from the methanol
extract of the plant. Five of these compounds, namely, carexines A–E, are previously
undescribed natural products. All compounds were isolated for the first time from
C. praecox. The ACE-inhibitory activity of seven stilbenoid compounds was tested,
and (–)-hopeaphenol proved to be the most active (IC50 7.7 ± 0.9 μM). The enzyme–kinetic
studies revealed a mixed-type inhibition; therefore, domain-specific studies were
also conducted. The in silico docking of (–)-hopeaphenol to the ACE affirmed some
favorable interactions. In addition, the antiproliferative and antibacterial effects
of some compounds were also evaluated.
