— 129 — 



here the toxic action has diminished on the conversion in the alcohol- 

 group, pulegol shows, according to Lindemann, the same action as 

 pulegone. This may possibly be connected with the presence of the 

 double linking in the lateral isopropyl chain; if this is removed by 

 further reduction, we arrive at menthol, which is a but slightly active 

 body, whereas the corresponding ketone menthone possesses at any 

 rate a more powerful action. 



/CH^— CO /CHg /CHj-CHOH/CHg /CHg-CHOH /CH 3 



CH,.CH NciC CHg-CH Nc:C CH 3 -CH ^CH-CH 



\ / \ \ / \ \ \ 



CH- — CH 2 ^-"-3 CH 2 — ^-^"2 ^^3 CH« — CH g ^-"-s 



Pulegone Pulegol Menthol 



In the relation between menthone and menthol, an analogous 

 behaviour therefore shows itself as between camphor and borneol. 



Closely related to thujone as to its structure is sabinol, which according 

 to my examinations is the toxic principle 1 ) of savin oil, in which it 

 is present as acetate. It shows an action differing from that of all 

 other camphor species, viz., an injurious action on the blood, which 

 finds expression in this, that (in the dog) urine is passed which 

 contains blood and also methaemoglobin. The toxic action corresponds 

 to that observed in man, where savin oil, or decoctions of the branches, 

 have been taken for the purpose of bringing about abortion. Ac- 

 cording to Semmler's 2 ) examinations, sabinol is a hydroxyl derivative 

 of the terpene sabinene in which an isopropyl and methylene group are 

 situated in p-position; the latter is, according to Semmler, characteristic 

 of the "pseudo-group" of the terpenes. 



/CO-CH, /CH 3 /CHOH-CH, /CH, /CHg-CIi, /CH, 



CH 3 .CH _\c-CH CH-C \c-CH CH 2 :C ^CCH 



\-^V \ v — ^^ \ \^"' \ 



CH-CH 2 X CH 3 X CH CH 2 X CH 3 X CH— CH 2 X^ 



Thujone Sabinol Sabinene 



The terpene sabinene is a but slightly active body; in the organism, 

 an oxidation takes place at one part of the ring, but apparently not at 

 the same part where in sabinol the hydroxyl-group is situated; with this 

 agrees the fact that, apart from the difference in toxicity, the products 

 of conversion (or oxidation), obtained from the urine, are not the same. 



For camphene, which, according to Semmler's 3 ) examinations, 

 belongs to the pseudo-class of the terpenes, the conversions could be 

 followed in the animal body, as it was found that camphene in the 



2 ) H. Hildebrandt, Arch. f. exp. Pharmakol. 45 (1901). 



2 ) Berl. Berichte 85 (1902), 2045. 



3 ) Ibidem 33 (1900), 3423. 



