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The article offers a study which illustrates the existence of xanthones from the roots of Calophyllum membranaceum, an evergreen plant of genus Calophyllum. It says that a root of C. membranaceum from Hainan Province, China was processed at which compounds were extracted. Moreover, it states that, using silica gel column, Sephadex LH-20, and preparative thin layer chromatography (PTLC), several compounds were isolated, including brasixanthone F, gracilixanthone, and methoxy-3-hydroxyxanthone.

Two new lanostane triterpenoids, 20-hydroxyeuphorbol-7-one (1) and 15α-hydroxyeuphorbol-7,11-dione (2), together with four known triterpenoids, euphorbol- 7-one (3), friedelin (4), stigmast-4-ene-6α-ol-3-one (5), stigmasta-4-en-3,6-dione (6), were isolated from ethanol extract of the branches and leaves of Polyalthia obliqua. The structures of 1 and 2 were elucidated on the basis of extensive spectroscopic analysis and comparisons with related known compounds. Antibacterial activities of two new compounds and four known compounds were tested. [ABSTRACT FROM AUTHOR]

A new flavonol, 4'-hydroxy-8,3'- dimethoxy-6-acroleinylflavan-3,4-diol (1) has been isolated from the ethyl acetate extract of stem-bark of Premna fulva Craib, together with six known compounds, vanillic acid(2), syringaresinol(3), naringenin(4), p-hydroxybenzoic acid (5), apigenin (6) and vitexin (7). The structure of 1 was elucidated on the basis of chemical evidence and intensive spectroscopic analysis including HR-ESI-MS, 1D and 2D-NMR. Compounds 1,3,5,6 and 7 were firstly isolated from this plant. To our regret that compound 1 exhibited no activities towards human cancer cell lines HL-60, BGC-823 and Bel-7402 on the bioassay experiments. [ABSTRACT FROM AUTHOR]

A correction to the article "Two New Lanostane Triterpenoids from the Branches and Leaves of Polyalthia oblique," by L. K. Wang and colleagues, that was published in the October 29, 2015 issue is presented.