BEXZoix. 449 



Vol. L, p. 232. 



Benzoin. According to observations made in Java by 

 Tschirch, " the trees yielding benzoin have no secretory receptacles, 

 and do not contain any secretion, the leaves, flowers, bark and 

 wood being entirely free from odour ; and it is only when the plant 

 is wounded that the odoriferous benzoin exudes, consequently it 

 must be regarded altogether as a pathogenic product."* Fritz 

 Ludy has endeavoured to ascertain the substance which gives rise 

 in this way to the formation of Benzoin,-j- the material for that 

 purpose having been supplied by Professor Tschirch. 



By treatment with ether, Siam Benzoin, like the Sumatra 

 variety, is almost completely dissolved, the residue amounting to 

 only 1-6 to 3*3 per cent. On shaking the ether solution with dilute 

 alkali solution, it suddenly solidified to a gelatinous mass of 

 crystals, from which the ether could not be separated. Upon 

 adding some alcohol, crystals of potassium salt of benzoresinol 

 were deposited after some hours. By using a very dilute alkaline 

 solution, and leaving it for some in contact with the ether 

 solution of benzoin, without shaking, a sharp separation of the 

 two liquids was effected. The dark-coloured watery liquid was 

 drawn off, and the ether solution repeatedly washed with very 

 dilute caustic alkali. By treatment of this etlier solution with 

 sodium sulphite, no evidence of the presence of aldehydes was 

 obtained. On distillation of the ether a yellowish thick liquid of 

 very aromatic odour remained, amounting to about 0-3 per cent, 

 of the benzoin, and probably consisting of a benzoic ester, the 

 alcoholic constituent of which was not ascertained. In this way 

 it was found that styrol, benzaldehyde, benzene, styracin and 

 phenyl-propyl cinnamic ester (Cj g H^ g 0.), which are constituents 

 of Sumatra benzoin, are not present in Siam benzoin. The 

 alkaline liquor contained benzoic acid, vanillin amounting to 0-15 

 per cent, of the benzoin, and a resinous substance which gave no 

 benzaldehyde when warmed with permanganate, but resembled 

 the product obtained from Sumatra benzoin. This was found to 

 consist of benzoresinol and siaresinotannol — a substance analogous 

 to resinotannol. Benzoresinol, Cj g H„ ^ Oo, from Siam benzoin, is a 

 white amorphous substance, without taste or odour, meltino- at 



* Pharm. Journ. [3], xxiii., p. 886. 

 t Arcliiv. der Pharm., xliii., p. 231. 

 FF 



