The Antiproliferative Activity and NO Inhibition of -Clerodane Diterpenoids from in RAW 264.7 Macrophages.

In this study, nine -clerodane-type diterpenoids (-) were isolated from the dichloromethane extract of Bedolla & Zamudio leaves. Compounds - were new natural products, and - were acetone artifacts. In addition, four -clerodanes diterpenoids (-) previously described from different sources and six triterpenoids-identified as 3β,20,25-trihydroxylupane, oleanolic acid, 3β--acetyl-oleanolic acid, ursolic acid, 3β--acetyl-betulinic acid, and 3β,28--diacetyl-betulin-were isolated. Additionally, five flavonoids were also isolated from the methanol extract: quercetin-3--β-xylopyranosyl-(1 → 2)-β-galactopyranoside, taxifolin-7--β-glucopyranoside, naringenin-7--β-glucopyranoside, a mixture of 2 and 2 eriodictyol-7--β-glucopyranoside, caffeic acid, the methyl ester of rosmarinic acid, and rosmarinic acid. The structure of the isolated compounds was established by spectroscopic means, mainly H and C NMR, including 1D and 2D homo- and heteronuclear experiments. The absolute configuration of and was ascertained via an X-ray analysis, and that of the other compounds via ECD. The antiproliferative activity of some diterpenoids was determined using the sulforhodamine B method, where guevarain B () and 6α-hydroxy-patagonol acetonide () showed moderate activity against the K562 line, with IC (μM) = 33.1 ± 1.3 and 39.8 ± 1.5, respectively. The NO inhibition in RAW 264.7 macrophage activity was also determined for some compounds, where 2-oxo-patagonal (), 6α-hydroxy-patagonol acetonide (), and 7α-acetoxy--clerodan-3,13-dien-18,19:16,15-diolide () were proven to be active, with IC (μM) of 26.4 ± 0.4, 17.3 ± 0.5, and 13.7 ± 2.0, respectively. The chemotaxonomy of is also discussed.