Isolation and identification of phytochemical constituents from Scrophularia takesimensis

Phytochemical constituents were isolated from Scrophularia takesimensis (Scrophulariaceae) using repeated chromatography and prep-HPLC. Their structures were elucidated as stigmast-5-en-3-ol (1), α-spinasterol 3-O-β-d-glucopyranoside (2), 5-hydroxypyrrolidin-2-one (3), trans-cinnamic acid (4), 4-methoxycinnamic acid (5), 2-methoxycinnamic acid (6), and 5,7-dihydroxy-4′-methoxyflavone (7) by spectroscopic analysis. All compounds were isolated for the first time from S. takesimensis and compounds 2, 3, 6, and 7 were isolated for the first time from Scrophularia species. Among them, 5,7-dihydroxy-4′-methoxyflavone (7) exhibited strong AR inhibitory activity, with an IC50 value of 4.96 μM. The content of 5,7-dihydroxy-4′-methoxyflavone (7) was measured in aerial parts of S. takesimensis, S. kakudensis and S. boreali-koreana (54.3, 25.4, and 15.0 μg/g, respectively) by HPLC.   Key words: Aldose reductase inhibition, HPLC analysis, phytochemical constituent, Scrophularia takesimensis.