Diverse prenylated C6-C3 derivatives from the stems and branches of Illicium ternstroemioides A. C. Smith with anti-inflammatory and antiviral activities

Abstract

Fifteen unreported prenylated C₆-C₃ derivatives (1-15) were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith, including one bis-prenylated C₆-C₃ derivative (1), three prenylated C₆-C₃ derivative-shikimic acid ester hybrids (2-4) and 11 prenylated C₆-C₃ monomers (5-15). The structures of compounds 1-15 were elucidated by spectroscopic analysis (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of the compounds were determined using electronic circular dichroism (ECD), induced circular dichroism (ICD), and the modified Mosher's method. Among the isolates, compounds 11, 12, and 15 exhibited significant anti-inflammatory activities by inhibiting the nitric oxide with IC₅₀ values ranging from 1.89 to 24.83 μM in lipopolysaccharide-stimulated murine RAW 264.7 macrophages and murine BV2 microglial cells; compounds 2, 3, and 7 exhibited antiviral activitives against Coxsackievirus B3 with an IC₅₀ value of 33.3, 25.9, and 27.8 μM, respectively.

Keywords: Anti-Coxsackievirus B3 activity; Anti-inflammatory activity; Illiciaceae; Illicium ternstroemioides A. C. Smith; Prenylated C(6)-C(3) derivatives.