Title: Balsam Gurjun
Additional Names: Wood oil; "East Indian Copaiba"
Literature References: Oleoresin from various species of Dipterocarpus, Dipterocarpaceae. Habit. Eastern India, Burma. Constit. About 75% volatile oil, boiling at about 255°; gurjunic acid, resin, bitter substance sol in water. Isoln of an optically inactive sesquiterpene d-elemene, from gurjun balsam: Gough, Powell, Tetrahedron Lett. 1961, 763.
Properties: Clear liquid, light brown by transmitted light with greenish fluorescence; somewhat bitter, but not very acrid taste. Acid no. 5-15. Sapon no. 10-20 (2 g in 20 g xylene for 1 hr). d 0.95-0.97; [a]D -23 to -70°; nD28 1.510-1.516. Insol in water. Completely sol in benzene, chloroform; incompletely in alcohol, ether, carbon disulfide, petr ether.
Optical Rotation: [a]D -23 to -70°
Index of refraction: nD28 1.510-1.516
Density: d 0.95-0.97
Use: As of copaiba; adapted for varnishes and lacquers, particularly for articles to be exposed to a temp of 80° or so. |