62 CINCHONA BARKS. 
(quinovin or kinovin). It was discovered in 1821 by Pelletier and 
Caventou, in Cinchona nova surinamensis, and named by them 
“acide quinovique’”’; it was afterward designated by others as chzno- 
va-bitter or cinchona-bitter, and in 1859 was recognized by Hlasi- 
wetz as a glucoside. Chinovin is best extracted from fresh 
Indian barks by means of a dilute alkali, and is precipitated there- 
from, according to De Vrij, by hydrochloric acid. In order to 
purify it, the chinovin is dissolved in milk of lime and again pre- 
cipitated. After having been subjected to this treatment several 
times, it is finally dissolved in chloroform. Chinovin is scarcely 
soluble in water, but is soluble in acetone, ether and alcohol; 
although neutral, it forms compounds with the alkalies, which are 
mostly soluble in water, and possess a very bitter taste. It is 
probable that a portion of the alkaloids in Cinchona barks is in 
combination with chinovin. According to Hlasiwetz, chinovin, 
C,.H,,O,, in alcoholic solution, is split, by the action of hydrochloric 
acid, into chimovie (quinovic or kinovic) acid C,,H,,O, and a smeary 
variety of sugar (afterward recognized as mannitan),* C;H,,O 
whereby a molecule of water is absorbed. 
CZN,0, + HO == 0,H,0, + CjH;,,0; 
patie, cvsnet Sy ie aE. pall 
Chinovin. Chinovie Acid. Mannitan. 
If an alcoholic solution of chinovin, diluted with a little water, is 
brought in contact with sodium amalgam, there is obtained, upon 
concentration, chinovate of sodium, as Rochleder (1867) has 
shown. 
Chinovin participates in the medicinal activity of Cinchona 
barks.* The plane of polarization is deviated by its solutions, as 
well as by those of chinovic acid, to the right. The latter forms 
rhombic laminz, and is of a feebly acid nature; it dissolves only 
in boiling alcohol somewhat abundantly, but neither in chloroform 
nor in water. Chinovin, associated with chinovic acid, is not con- 
fined in the Cinchonas to the bark, but is distributed through all 
their parts. De Vrij, in 1860, found in dried leaves of Cinchonas 
cultivated in India as much as 2 per cent.;in the trunk bark as 
much as 1.4 per cent., and in the root bark 1 per cent. of chinovin; 
decomposition of chinovin is thus considered to take place according to the following 
equation Cian 
Kid 
C,sH,20),; = C32H 4,06 + C.H,,0, + H,0. 
te ————— ay ; 
; Chinovin Chinovic acid Chinovin sugar. 
_ 1 Liebermann and Giesel, /oc. cit., p. 935, place the identity of this sugar with mannitan 
in question, but find the sugar obtained by the decomposition of both varieties of chino- 
vin to be identical. (F. B. P.) ; 
* Kerner, in the Géschen Deutsche Klinik, 1868, No. 9. 
