• Natural Product Sciences
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• v.24 no.1
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• pp.47-53
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• 2018

Callophylum symingtonianum (Guttiferae), an evergreen broad-leaved tree that usually grows in hill forests, can be found distributed in the Malay Peninsula. The barks, leaves, flowers and seeds is often used medicinally to treat diarrhea and rheumatism. In the present study, we isolated two inophyllum type coumarins, 12-O-ethylinophyllum D (1) and iso-soulattrolide (2) from the stembarks of C. symingtonianum together with their antibacterial activity. The compounds were isolated by chromatographic methods on a silica gel. The structures were established by spectroscopic methods including UV, IR, (1D and 2D) NMR and mass spectrometry as well as by comparison with several literature sources. The antibacterial activity of those compounds was tested using a disc-diffusion assay against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Both compound exhibited mild inhibition against P. aeruginosa with both $111{\mu}g/ml$ MIC value. Compound 2 also inhibits S. aureus with $25{\mu}g/ml$ MIC value.

• Natural Product Sciences
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• v.12 no.3
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• pp.138-143
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• 2006

Our continuing interest on Garcinia and Mesua species has led us to carry out a detail study on the chemistry of the root bark of Garcinia mangostana (Guttiferae) since this part of the plant has not been investigated before, and the strm bark of Mesua corneri (Guttiferae) an uninvestigated species. This study has yielded six xanthones, ${\alpha}-mangostin$ (1), ${\beta}-mangostin$ (2), ${\gamma}-mangostin$ (3), garcinone-D (4), mangostanol (5) and gartanin (6) from Garcinia mangostana and two xanthones rubraxanthone (7) and inophyllin B (8) from Mesua corneri. Structural elucidations were achieved using $^1H,\;^{13}C$ NMR and MS data. The crude hexane and chloroform extracts of the root bark of Garcinia mangostana and the hexane extract of the stem bark of Mesua corneri were found to be active against CEM-SS cell lines with $IC_{50}$ values less than $30\;{mu}g/ml$. Moreover, ${\gamma}-mangostin$ gave a very low $LC_{50}$ value of $4.7\;{mu}g/ml$ while rubraxanthone gave an $LC_{50}$ value of $5.0\;{mu}g/ml$ indicating these two compounds to be potential lead compounds for anti-cancer activity against the CEM-SS cell line. This paper reports the isolation and identification of these compounds as well as bioassay data for the crude extracts, ${\gamma}-mangostin$ and rubraxanthone.

• Natural Product Sciences
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• v.10 no.5
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• pp.220-222
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• 2004

A new prenylated pyranoxanthone, inophyllin B (1), was isolated from the roots of Calophyllum inophyllum (Guttiferae). Together with this compound was also isolated the known pyranoxanthone brasilixanthone B (2) and two common triterpenes friedelin (3) and sitosterol (4). Structural elucidations of these compounds were achieved through $^1H,\;^{13}C$, DEPT, COSY, HSQC and HMBC experiments. The molecular mass was determined using MS techniques. The crude extract indicated weak toxicity to the larvae of Aedes aegypti. We report here the isolation, structural elucidation and bioassay data for Inophyllin B and brasilixanthone B.

• Korean Journal of Pharmacognosy
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• v.37 no.3
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• pp.162-168
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• 2006

The isolation and identification of a new xanthone (6-0-palmitolyl-1,6-dihydroxy-5,7-dimethoxyxanthone) along with n-alkanols, fatty acids, 1,6-dihydroxy-5,7-dimethoxyxanthone, 1,7-dihydroxykanthone, betulinic acid, ${\beta}-sitosterol$, methyl 4-hydroxybenzoate, quercetin, and kaempferol from the aerial parts of Hypericum ascyron was reported. The structures were elucidated by spectroscopic methods, mainly NMR and mass spectrometry.

• Natural Product Sciences
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• v.9 no.3
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• pp.174-176
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• 2003

Studies on the stem bark extracts of Garcinia cuneifolia have furnished a new xanthone cuneifolin (1) and the triterpene stigmasterol (2). Structures for these compounds were elucidated based on NMR, 2D NMR, MS and GCMS data. Larvicidal activity screening of the crude bark extract using the larvae of Aedes aegypti indicated the larvae to be susceptible to these extracts. $LC_{50}$ values of the bioassays show the extracts to be moderately toxic to the larvae of Aedes aegypti.