STYRAX 293 



4 per cent. When boiled with a solution of potassium dichromate 

 and sulphuric acid it evolves an odor resembling that of bitter 

 almonds (due to the presence of cinnamic acid) ; it forms little or no 

 foam when mixed with an equal volume of alcohol and shaken with 

 ammonia water, indicating the absence of turpentine and fixed oils. 



Constituents. Storax consists of about 50 per cent of two resin 

 alcohols, a-storesin and 0-storesin, which are partly free, partly in 

 combination with cinnamic acid and partly with sodium, a-storesin 

 (a-storesinol) is an amorphous substance that is very sparingly sol- 

 uble in water and forms a crystalline compound of potassium. 

 /3-storesin (/3-storesinol) occurs in white flakes which are somewhat 

 soluble in water but do not form a crystalline compound of potassium. 

 Storax also contains from 10 to 20 per cent of an ester consisting of 

 cinnamic acid and storesin; from 5 to 10 per cent of cinnamyl or 

 styryl cinnamate (styracin) which occurs in colorless, odorless and 

 tasteless needles and which on hydrolysis yields cinnamic alcohol 

 (styrone) and a salt of cinnamic acid; about 10 per cent of an odor- 

 less, viscid substance, phenyl-propyl cinnamate; from 2 to 3 per 

 cent of phenyl ethylene (styrol or styrene), which occurs as a color- 

 less liquid possessing the odor and pungent taste of storax; from 

 0.5 to 1 per cent of a volatile oil which is Isevo-rotatory and consists of 

 a hydrocarbon, styrene, about 0.4 per cent of an oxygenated com- 

 pound (styrocamphene), and cinnamates of ethyl, benzyl, phenyl- 

 propyl and cinnamic alcohols; from 2 to 5 per cent of free cinnamic 

 acid; a small quantity of iso-cinnamic acid which occurs in colorless 

 crystals; a crystallizable substance, styrogenin; about 0.15 per 

 cent of vanillin; a trace of benzoic acid; ethyl vanillin; resin, and 

 caoutchouc. Storax sometimes yields more than 20 per cent of free 

 cinnamic acid and is the best available source of this substance. 



Allied Plants. Liquidambar Styraciflua, a tree indigenous to 

 the eastern and southern United States and Mexico, yields the 

 American storax, which occurs as a yellowish-brown, semi-liquid 

 mass somewhat resembling Levant storax. It probably contains 

 related storesins (storesinols), which appear to form similar com- 

 binations with cinnamic acid. On distillation of the fresh balsam 

 about 7 per cent of a volatile oil is obtained, which is dextrorotatory 

 and contains styrol and a body with the odor of oil of turpentine, 

 the cinnamyl-ethyl-ester and cinnamyl-benzyl-ester being wanting. 

 It also contains phenyl-propyl-cinnamate, styracin, styrol, free 

 cinnamic acid and vanillin. On account of the scarcity of Levant 

 styrax, the American product has attracted considerable attention. 

 It contains 28 per cent of cinnamic acid, 22.86 per cent of cinna- 



