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Updated: Apr 11, 2026

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro
Published on: July 5, 2017
Venuloxanthone, a new pyranoxanthone from the stem bark of Calophyllum venulosum
Ahmad Azri Fitri Bin Ismail1, Gwendoline Cheng Lian Ee1, Shaari Bin Daud1,2
1a Chemistry Department , Faculty of Science, Universiti Putra Malaysia , Serdang 43400 , Selangor , Malaysia.
Abstract:
A new pyranoxanthone, venuloxanthone (1), was isolated from the stem bark of Calophyllum venulosum, together with three other xanthones, tovopyrifolin C (2), ananixanthone (3) and caloxanthone I (4), along with two common triterpenes, friedelin (5) and lupeol (6). The structures of these compounds were identified using several spectroscopic analyses which are NMR, GCMS and FTIR experiments.
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