— 203 — 



they obtained q/dohexanone-2-carboxylic acid, an acid which begins to 

 soften at 79° and decomposes at 81 to 82°. By reducing this acid with 

 sodium-amalgam they obtained q/dohexanol-2-carboxylic acid (hexahydro- 

 salicylic acid), m. p. 111°. From l-methyl-q/cfohexane-3-one (from pulegone) 

 they derived d-l-methyl-c^cfohexane-3-one-2(?)-carboxylic acid, m. p. 103°, 

 Md + 97,2 . The inactive acid melts at 100°. 1 -Methyl-ci/c/ohexane-4- 

 one-3-carboxylic acid melts at 101° and, when reduced with sodium amalgam, 

 yields l-methyl-c?/c/ohexane-4-ol-3-carboxylic acid (m.p. 114°), from which by 

 the action of heat, methyl-q/cfohexene carboxylic acid (b. p. 153° at 25 mm.) 

 is obtained. The authors also obtained menthone carboxylic acid (m. p. 154°) 

 and thymomenthone carboxylic acid (m.p. 150 to 151°). All these acids 

 contain the atomic group COCHCOOH and give intense colorations with 

 ferric chloride. The formation of the acids proceeds as follows: — 



CH 2 CH 2 CrVCHNa CH 2 CH(COOH) 



M 2 C<T \C0 — > H.c/ \C0 — I 



CH 2 CH, CH 2 CB 



Cinnamic acid. As mentioned in our last Report, Riiber and Gold- 

 schmidt 1 ) ascribe the differences in the behaviour of synthetic and storacic 

 cinnamic acid to the presence of substituted cinnamic acids as impurities. 

 rZrlenmeyer and Hilgendorf 2 ) oppose this view, and give it as their opinion 

 that the differences in the cinnamic acids are due, not to contamination 

 by a substitution product, but to differences in the benzaldehydes used 

 for the preparation of the acids. The authors promise to publish the re- 

 sults of their examination of the various benzaldehydes. 



Nitrogenous bodies. 



On the occurrance of hydrocyanic acid in some species of Thalictrum, 

 see under Phyto-physiological Notes, p, 172. 



Skatol. T. Sasaki 3 ) recently has described an exceptionally sensitive 

 reaction for skatol, by which the presence of this body may be detected in a 

 dilution of 1 : 500 000. The process consists of diluting 3 cc. of a skatol 

 solution with 3 drops of methyl alcohol and underlaying the solution with 

 3 cc. of concentrated sulphuric acid, when a violet ring appears at the 

 plane of contact of the two liquids. When the solution is shaken up the 

 whole of it acquires a reddish-violet tint. This reaction is not produced 

 with either indol or «-methylindol. 



x ) Berl. Berichte 43 (1910), 453; Report April 1910, 189. 



2 ) Berl. Berichte 43 (1910), 955. 



'•) Biochem. Zeitschr. 23 (1910), 402. 



