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(-)-N-Formylanonaine (1), (-)-oliveroline (2), (+)-nornuciferine (3), lysicamine (4), (+)-cyperone (5), (+)-epi-yangambin (6), ficaprenol-10 (7), pheophytin a (8), aristophyll C (9) and michephyll A (10) were isolated from the leaves of Michelia alba DC (Magnoliaceae). Among them, 10 is a new compound. The structures of these compounds were characterised and identified by spectral analyses. We have also presented the antioxidation activity of 10.

We have continued the study of constituents from Michelia alba >1@. To further understand the chemotaxonomy and to continue searching for novel agents from Magnoliaceous plants, the stems of M. alba were chosen for the first time for phytochemical investigation. In this paper, we report the isolation of 20 pure substances. The compounds, including six aporphines, (-)-anonaine (1), (-)-norushinsunine (2), (-)-ushinsunine (3), (-)-N-formylanonaine (4) [2], (-)-romerine (5) [3], and (-)-asimilobine (6) [4]; two oxoaporphines, liriodenine (7) and oxoxylopine (8); one lignan, (+)-syringaresinol (9); one amide, N-trans-feruloyltyramine (10); seven benzenoids, 4-hydroxybenzaldehyde (11), p-anisaldehyde (12) [5], veratraldehyde (13) [5], 3,4,5-trimethoxybenzoic acid (14) [6], 3,4-dimethoxybenzoic acid (15) [7], eugenol (16) [8], and methyl isoeugenol (17) [8]; one triterpenoid, ficaprenol (18) [9]; two steroids, E-sitosterol (19) [10] and stigmasterol (20) [10], are isolated from the stems of Michelia alba. Compounds 4, 5, and 6 and 12-18 were isolated for the first time from this species [2].The MeOH extract (156.7 g) was obtained from M. alba according to the literature method >1@ (89.2 g) and H 2 O (60.8 g). The CHCl 3 -soluble fraction was chromatographed over silica gel (800 g, 70-230 mesh) using n-hexane-EtOAcCHCl 3 -MeOH mixtures as eluents to produce five fractions. Part of fraction 1 (12.86 g) was subjected to silica gel chromatography by eluting with n-hexane-EtOAc (40:1) and enriched gradually with EtOAc to furnish three fractions (1-1-1-3). Fraction 1-1 (5.32 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain eugenol (16) (23 mg), methylisoeugenol (17) (18 mg), and ficaprenol (18) (20 mg). Fraction 1-2 (4.63 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain p-anisaldehyde (12) (19 mg), veratraldehyde (13) (22 mg), 3,4,5-trimethoxybenzoic acid (14) (26 mg), and 3,4-dimethoxybenzoic acid (15) (25 mg). Fraction 1-3 (3.28 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain E-sitosterol (19) (45 mg) and stigmasterol (20) (38 mg). Part of fraction 2 (9.33 g) was subjected to silica gel chromatography by eluting with n-hexane-EtOAc (30:1) and enriched with EtOAc to furnish two further fractions (2-1-2-2). Fraction 2-1 (5.22 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain liriodenine (7) (62 mg). Part of fraction 2-2 (3.62 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain (+)-syringaresinol (9) (30 mg). Part of fraction 3 (11.36 g) was subjected to silica gel chromatography by eluting with n-hexane-EtOAc (10:1) and enriched with EtOAc to furnish three further fractions (3-1-3-3). Fraction 3-1 (5.59 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain oxoxylopine (8) (18 mg). Fraction 3-2 (5.45 g) was further purified on a silica gel column using n-hexane-EtOAc mixtures to obtain 4-hydroxybenzaldehyde (1...

The stems of Cinnamomum reticulatum Hay (Lauraceae) were extracted with hexane and chloroform successively. A series of new esters, including a mixture of 4-hydroxy-3-methoxyphenethyl derivatives, along with two butanolides, isoobtusilactone A and obtusilactone A, two amides, N-trans-feruloylmethoxytyramine and N-cis-feruloyl-methoxytyramine, three benzenoids, p-hydroxybenzoic acid, syringic acid and vanillic acid, one lignan, (+)-syringaresinol and one steroid, beta-sitostenone, were isolated. The structures of the new esters were elucidated by chemical and physical evidence.

Ficumone, a 2-oxetanone isolated from the fruits of Synsepalum dulcificum, has been characterised as (R*)-4-hydroxy-2-oxetanone by means of spectroscopic methods.