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A novel homosesquiterpenoid, burmanol (1), along with 16 known compounds, including one triterpenoid, one quinol, two chlorophylls, two coumarins, two steroids, three lignans and five benzenoids were obtained from the stems of Cinnamomum burmanii (Lauraceae). The structures of these compounds were determined on the basis of spectroscopic analysis.

Synsepalum dulcificum Daniell (Sapotaceae) is an evergreen shrub native to tropical West Africa; its fruit and red berries have the property of remarkably altering the sour taste to a sweet taste [1]. This explains why the berry has been called "miracle fruit or mysterious fruit". In the course of screening for chemically novel agents from plants, S. dulcificum was chosen for further phytochemical investigation [2][3][4][5]. In this study, the MeOH extract of its stems was subjected to chromatographic separation to afford six pure compounds, including propane-1,2,3-triol (1), 2,5-dimethoxyphenol (2), 3,4,5-trimethoxybenzoic acid (3), nicotinic acid (4) [6], E-sitosterol (5), and stigmasterol (6) [7]. Among them, 2 was isolated from natural sources for the first time though they had been synthesized previously [8], and 1-4 were obtained for the first time from this plant [2][3][4][5]. In this paper, we report the isolation and structure elucidation of 2.2,5-Dimethoxyphenol (2) was obtained as a brown powder. Its molecular formula was deduced as C 8 H 10 O 3 by HR-ESI-MS m/z 177.0521 ([M + Na] + ; calcd 177.0528). The UV spectroscopic absorptions at 225, 265, and 305 and the IR spectrum show absorptions for the hydroxyl group (3400 cm -1 ) and an aromatic moiety (1590 and 1510 cm -1 ). The 1 H NMR spectrum clearly indicated the presence of two methoxy groups at G 3.88 (3H, s) and 3.91 (3H, s), one hydroxy group at G 7.32 (1H, s), and three ABX methine protons at G 6.90 (1H, d, J = 8.3, H-3), 7.55 (1H, d, J = 1.8, H-6), and 7.58 (1H, dd, J = 8.3, 1.8, H-4). The carbons of the 2,5-dimethoxyphenol were assigned, from 13 C NMR and DEPT experiments, to two methyls at G 56.4 (5-OCH 3 ) and 56.7 (2-OCH 3 ), three methines at G 108.2 (C-6), 113.7 (C-4), and 124.1 (C-3), and three quaternary carbons at G 145.4 (C-2), 148.7 (C-1), and 155.1 (C-5). The structure of 2 was also confirmed by 2D NMR experiments.

Pressafonin A (1) and pressafonin B (2), two new Michelia monoterpenic esters, have been isolated from Michelia compressa (Maxim.) Sargent var. formosana Kanehira (Magnoliaceae), and their structures are determined on the basis of spectroscopic analysis.