Origin and Production. Genuine angostura bark comes from Venezuela and the upper Orinoco and is derived from Cusparia trifoliata, Engl. (Galipea Cusparia, St. Hil., G. officinalis, Hancock3), family Rutacese). Upon distillation with water vapor it yields 1,04), 1,55) to 1,96) p.c. of volatile oil with an aromatic odor and taste. The light yellow color of the fresh oil becomes dark upon standing. d15,0,928 to 0,96; aD - 7°30' to - 50°; nD20o 1,50744; A.V.I,8; E. V. 5,5; E. V. after acetylation 35,7; with 9 vol. of 90 p.c. alcohol it forms a turbid solution4).
Composition. According to the extensive investigations of H. Beckurts and ). Trceger7), the aromatic principle of angostura bark oil is a sesquiterpene alcohol galipol, C15H260. It boils between 260 and 270°, has a specific gravity of 6,9270 at 20°, is optically inactive and is present to the extent of about 14 p.c. It is very unstable, giving off water at higher temperatures.
l) Hardy, Bull. Soc. chim. II. 24 (1876), 497; Chem. Zentralbl. 1876, 70.
8) Report of Schimmel & Co. April 1899, 27.
3) Comp. C. Hartwich and M. Gamper, Beitrage zur Kenntnis der Angosturarinden. Arch, der Pharm. 238 (1900), 568.
4) Report of Schimmel & Co. April 1913, 26.
5) Schimmel's Bericht April 1890, 47.
") Oberlin and Schlagdenhauffen, Journ. de Pharm. et Chim. IV. 26 (1877), 130; Jahresb. d. Pharm. 1877, 178.
7) Arch, der Pharm. 235 (1897), 518 and 634; 236 (1898), 392. - Comp. also Beckurts and Nehring, ibidem 229 (1891), 612 likewise Herzog, ibidem U3 (1858), 146.
Another important constituent is cadinene, C16H24, to which is due the lasvorotation of the oil. It was characterized by its hydrohalogen addition products.
In addition to the laevogyrate cadinene and the inactive alcohol, the oil contains an inactive sesquiterpene, named galipene, which boils at 255 to 260° and has a specific gravity of 0,912 at 19°. With hydrohalogens it forms liquid addition products that are readily decomposed.
Angostura bark oil also contains a small amount of a terpene that appears to be identical with .pinene.