— 80 - 



E. Rudderi, Maiden, E. Baueriana, Schauer (E. subrotunda, R. Br. ; E. poly- 

 unthemos, Benth. non Schauer; E. Fletcheri, R. T. Baker with the var. conica. 

 Maiden and E. eneorifolia, D. C. (E. stricta, R. Br. non Sieb.; E. hypericifolia, 

 Link; E. myrtiformis, Naudin [?]). 



Oil of Fagara Aubertia, see Oil of Xanthoxylum Aubertia, p. 134. 



Oil of Fagara xanthoxyloides. In our last two Reports (April 1911, 73; 

 October 1911, 49) we referred to xanthotoxin, an interesting body which 

 has been found by Thorns in the root oil of Fagara xanthoxyloides. 

 Even at that time, Thorns surmised xanthotoxin to be a coumarin-like 

 compound, related to citroptene. His latest investigations 1 ) have con- 

 firmed the correctness of this supposition. By extracting the shells with 

 alcohol, Thorns obtained a solid substance (m. p. 128°) which was split 

 up by repeated re crystallisation into two parts, xanthotoxin (m. p. 145 

 to 146°) and bergaptene (m. p. 190 to 191°), the latter a constituent of 

 bergamot oil. The two bodies are isomeric, but bergaptene is a phloro- 

 glucinol derivative, whereas xanthotoxin is derived from pyrogallol. 



Besides nitroxanthotoxin, which has already been described 2 ), Thorns 

 prepared methylxanthotoxic acid (m. p. 114 to 117°) and methylxanthotoxin 

 methylate (m. p. 44°). The isomeric methylbergaptene methylate melts at 

 52°. When melted with potash, pyrogallol carboxylic acid is formed, from 

 which it is evident that xanthotoxin is a pyrogallol derivative to which the 

 molecular structure reproduced below applies, assuming that no atomic 

 transposition takes place during the melting-process. 



Experiments with sticklebacks showed that the narcotic power of 

 xanthotoxin is considerably higher than that of bergaptene. 



From a botanical point of view the occurrence of xanthotoxin and 

 bergaptene in Fagara xanthoxyloides, and of bergaptene in the fruit of 

 €itrus Bergamia, the parent-plant of bergamot oil, is interesting, for the 

 two plants are closely related, belonging to sub-divisions of the same 

 botanical family, namely: Rutacece-Xanthoxylece and Butacece-Aurantoidece. 



OCH 3 OCH 8 



lCH:CH 



/-0 



O • CO ^HC 



CH<f 

 CH:CH \-0 



O • CO 



Xanthotoxin. One of the formulae 



given for bergaptene by Pomeranz 3 ). 



Another body which has been isolated by Thorns and F. Thumen Ij 

 from the root-bark of Fagara xanthoxyloides by extracting with benzene 



*) Berl. Berichte 44 (1911), 3325. 



8 ) Comp. Report October 1911, 50. 



9 ) Monatsh. f. Chem. 12 (1891), 379. 

 *) Berl. Berichte 44 (1911), 3717. 



