A sugar ester and an iridoid glycoside from Scrophularia ningpoensis

Abstract From cytotoxic extracts of the roots of Scrophularia ningpoensis Hemsl. (Scrophulariaceae) a new sugar ester, ningposide D (3- O -acetyl-2- O - p -methoxycinnamoyl-α(β)- l -rhamnopyranose) ( 1 ) and a new iridoid glycoside, scrophuloside B 4 (6- O -(2″- O -acetyl-3″- O -cinnamoyl-4″- O - p -methoxycinnamoyl-α- l -rhamnopyranosyl) catalpol) ( 2 ) along with known compounds: oleanonic acid ( 3 ), ursolonic acid ( 4 ), cinnamic acid ( 5 ), 3-hydroxy-4-methoxy benzoic acid ( 6 ), 5-(hydroxymethyl)-2-furfural ( 7 ) and β-sitosterol ( 8 ) were isolated. The structures of the new compounds were elucidated by spectral data (1, 2D NMR, EI, HRESI-MS and MS/MS). Oleanonic acid ( 3 ) and ursolonic acid ( 4 ) were found to be cytotoxic against a series of human cancer cell lines with IC 50  = 4.6, 15.5 μM on MCF7; 4.2, 14.5 μM on K562; 14.8, 44.4 μM on Bowes; 24.9, 43.6 μM on T24S; 61.3, 151.5 μM on A549, respectively. β-Sitosterol ( 8 ) inhibited Bowes cells growth at IC 50  = 36.5 μM. Scrophuloside B 4 ( 2 ) showed activity on K562 and Bowes cells at IC 50  = 44.6, 90.2 μM, respectively.