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Nine compounds, including six phenylethanoid glycosides: acteoside (1); bioside (2); echinacoside (3); poliumoside (4); phenylethyl glycoside (5); salidroside (6) and three flavonoids; linarin (7); apigenin (8); isorhoifolin (9), were isolated from the flowers of Buddleja officinalis MAXIM. (Buddlejaceae). Chemical structures were confirmed by (1)H-, and (13)C-NMR, and MS spectral methods and compared with those reported in the literature. Antioxidant activities of the methanol and water extracts, and all isolated compounds were evaluated using the total oxidant scavenging capacity (TOSC) assay against peroxynitrite. Results of the assay showed that the phenylethanoid glycosides, a major class of compounds of the flowers of B. officinalis, possess strong antioxidant activity. Of these, acteoside, echinacoside and poliumoside have 9.9-, 9.8- and 9.5-fold TOSC value, respectively, compared with the positive control, Trolox.

Sixteen new acylated iridoid glycosides, called buddlejosides A1-A16, were isolated from Buddleja japonica HEMSL., together with four known iridoid glycosides; 6-vanilloyl-ajugol, 6-feruloyl-ajugol, verbascoside A, and 6-O-[α-L-(4-O-feruloyl)-rhamnopyranosyl]-catalpol. Structures of the new compounds were determined on the basis of chemical and spectroscopic evidence. Buddlejosides A1 was an ajugol derivative acylated with monoterpenic acid, A2 was an sinuatol and A3-A16 were 6-rhamnopyranosyl-catalpol derivatives acylated with cinnamic acid derivative and acetic acid.

Two new triterpenoid glycosides, named mimengosides A (1) and B (2), along with acteoside (3) were isolated from the Buddlejae Flos (flower and bud of Buddleja officinalis). The structures of 1 and 2 were determined as 3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→3)-[β-D-glucopyranosyl-(1→2)-β-D-fucopyranoside of 16-dehydroxysaikogenin G and that of 3, 23, 28-trihydroxy-11-methoxy-olean-12-ene, respectively, by spectral and chemical methods.

Four new oleanane-type triterpene saponins, named buddlejasaponins I (1), II (2), III (3) and IV (4) were isolated from the aerial parts of Buddleja japonica HEMSL., together with a known saponin saikosaponin a (5). Their structures were elucidated on the basis of the chemical and spectroscopic studies.

Further toxic principle, buddledin C, and two additional sesquiterpenes, buddledin D and E, have been isolated from the root bark of Buddleja davidii FRANCH. The structures of buddledin C and D have been determined to be 3 and 4 by chemical transformation of buddledin A into buddledin D and dihydrobuddledin C (6), and by comparisons of their spectral data with those of buddledin A and its cis-isomer (8), which was obtained by the photoisomerization of 1. Structure 5 has been assigned for buddledin E by its spectral data and deuteration experiment.