Combretum quadrangulare

Combretum quadrangulare, or commonly known as sakae naa, is a small tree of the family Combretaceae, up to 10 m high. The tree grows wildly or is planted in Vietnam, Cambodia, Laos, Myanmar and Thailand.

The tree is planted along the banks of rivers or arroyos for firing. It is found throughout Thailand especially in open, wet places. Studies of the chemical constituents of this plant have revealed that alcoholic and other extracts from the roots and seeds could kill earthworms.

Description
Tree, 5-10m high: young branchlets acutely quad-rangular or very narrowly quadrialate. Leaves simple, opposite, elliptic or obovate, 3–8 cm wide, 6–16 cm long: petiole acutely ridged. Inflorescence in terminal and axillary spike; flower small, yellowish white. Fruit dry, thinly quadrialate: seed brownish red, ellipsoid, 4- angled.

Chemistry
Combretol is an O-methylated flavonol, found in C. quadrangulare. The plant also contains the gallic acid derivative, 1-O-galloyl-6-O-(4-hydroxy-3,5-dimethoxy)benzoyl-beta-D-glucose.