Abstract
A screening of the natural product chlorogenic acid, isolated from the
Brazilian medicinal plant Hypericum brasiliense, caffeic acid,
cinnamic acid, and p-methoxycinnamic acid, and derivatives of
caffeoylquinic, caffeoyl, and cinnamoyl against the enzymes prolyl
oligopeptidase and dipeptidyl peptidase IV was carried out. Caffeoylquinic,
caffeoyl, and cinnamoyl derivatives were prepared using simple
derivatization procedures and through coupling reactions with the amino acid
proline. The dipeptidyl peptidase IV assay showed inhibitory activity of the
tested compounds at a high concentration (500 µM) in the range of
81.5–7.2 %. In contrast, the derivatives methyl ester and 1,7-acetonide
obtained from chlorogenic acid, and caffeic acid and its methyl ester
derivative showed selectivity and activity as prolyl oligopeptidase
inhibitors, with IC50 values of 3 to 14 mM.
Key words
prolyl oligopeptidase - dipeptidyl peptidase IV - chlorogenic acid - caffeoyl and cinnamoyl derivatives -
Hypericum brasiliense
- Hypericaceae