by Semmler and Bartelt 1 ), who found that although teresantalic 

 acid does not stand in genetic relation to tricyclic a-santalol, it 

 also belongs to the tricyclic series. It melts at 15 7 , and has the 

 specific rotatory power [a] D — 70 24/ in 25 per cent, alcoholic solution. 

 From its ester, which was formed from the white silver salt unaffected 

 by light by means of methyl iodide (b. p. 85 to 86° at 1 1 mm. 

 pressure; d2o° 1,032; n D 1,47053; a^ — 63°45 / ; molecular refraction 

 found 48,8, calculated for C u H 16 2 48,3), there originated on reduction 

 with sodium and alcohol, the corresponding alcohol teresantalol 

 C 10 H 16 O (m. p. 1 13°; Hd -j- ii° 58' in alcoholic solution). The latter 

 has an exceptional tendency for subliming, it possesses a camphor-like 

 odour, and can be acetylated quantitatively. Its chloride, obtained by 

 means of phosphorus pentachloride, yielded on reduction with sodium 

 and alcohol the not quite pure hydrocarbon teresantalane C 10 H 16 

 (b. p. 165 to 168 : d 20 o 0,892; n D 1,48033). 



When teresantalic acid was treated with hydrochloric acid gas in 

 methyl alcoholic solution, it yielded a chloride (m. p. 199 ) which 

 was converted by reduction with sodium and alcohol into dihydro 

 teresantalic acid C 10 H 16 O 2 (m. p. 226 ). By reducing the ester 

 of this acid (b. p. 88° at 9 mm. pressure; d2o° 1,0034; «p — 13 in 

 50 per cent, alcoholic solution; n p 1,46757; molecular refraction 

 found 50,42, calculated for C u H 18 2 50,23), Semmler and Bartelt 

 obtained the corresponding alcohol dihydro teresantalol C 10 H 18 O 

 (m. p. 171 ), which, however, is obtained more easily directly from 

 teresantalol by treatment with hydrogen chloride, and subsequent 

 reduction with sodium and alcohol. 



With regard to the constitution of teresantalic acid and dihydro - 

 teresantalic acid, it is, in the opinion of the authors, established beyond 

 doubt that the former is tricyclic saturated, and the latter bicyclic 

 saturated. The action of hydrochloric acid would therefore split up 

 a bridge-bond of the tricyclic system. Semmler and Bartelt imagine, 

 owing to the similarity between the teresantalol series and camphor, 

 that the constitution of the above-mentioned compounds is as follows: 

 CH CH 



H C 



H C 



H 2 C 







CH, 





H 3 CCCOOH 





TTP 







r'xj 



( 



:.ch 3 



Teresanl 



alic acid 





CCH S 



Dihydroteresantalic acid 



*) Berl. Berichte 40 (1907), 3101. 



