CURARE ALKALOIDS. 
§ 5I7-] 
427 
of the berries and seeds. The mucous membrane was red in patches and 
softened, and the small intestines were also inflamed. 
XI.—Curare Alkaloids. 
§ 517. Commercial curare is a black, shining, resinoid mass, about 
83 per cent, of which is soluble in water, and 79 in weak spirit. It is a 
complicated mixture of vegetable extracts, from various plants. Tube- 
curare, which, according to Pictet, is the commercial variety, has been 
shown by Boehm to contain two alkaloids, tubo-curarine, C 19 H 22 N0 4 .0H, 
a reddish powder with a bitter taste, and curine, C 18 H 19 N0 3 , which 
crystallises in colourless prisms and melts at 212 °. 
Calabash-curare, from Strychnos toxifera, is said to contain a substance, 
curarine, C 19 H 25 N 2 0. OH, which is amorphous and very bitter. It must be 
remembered that the name curarine has also been applied to the mixed 
alkaloids from commercial curare. 
Pot-curare, from Strychnos castelnaca, contains protocurine, C 20 H 23 NO 3 , 
a slightly toxic crystalline substance, melting at 306° ; protocuridine, 
C 19 H 21 NO 3 , a non-toxic crystalline substance, melting at 274°-276° ; and 
protocurarine, C 19 H 23 N0 2 , a toxic substance. These substances have not 
been fully investigated. 
Curare is an arrow poison 1 prepared by different tribes of Indians 
in South America, between the Amazon and the Orinoco ; therefore, 
samples are found to vary much in their poisoning properties, although 
it is noticeable that qualitatively they are the same, and produce closely 
analogous symptoms. It is now known that some of the curare is 
derived from different species of strychnos, and like the South American 
strychnines paralyses, and does not tetanise. It is not unlikely that the 
active principles of curare (or woorari) may be methyl compounds similar 
1 A constituent of the Borneo arrow poison is “ derrid,” a toxic principle obtained 
from a leguminous plant, the Derris elliptica ; it is a resinous substance, which has 
not yet been obtained in the pure state. It is said not to be a glucoside, nor to contain 
any nitrogen (Greshoff, Ber., xxiii. 3537-3550). 
The Comalis on the east coast of Africa prepare an arrow poison from the aqueous 
extract of the root of Oubaion, a tree closely related to Carissa Schimperii. 
Oubain is prepared by treating the aqueous extract with lead acetate, getting 
rid of excess of lead by SH 3 , and concentrating in a vacuum. The syrup is boiled 
with six times its volume of alcohol of 85°, and allowed to cool in shallow vessels ; 
crystals are obtained which are recrystallised, first from alcohol, and afterwards 
from water. 
Oubain, C 30 H 46 O 12 , forms thin white nacreous lamellae. It is tasteless, odourless, 
and neutral, almost insoluble in cold water, and soluble in boiling water ; it dissolves 
readily in moderately concentrated alcohol, is almost insoluble in absolute alcohol, 
and insoluble in ether and chloroform. Its melting-point is 200°. The solution of 
oubain in water is laevo-rotatory, [a] D = — 340. It is a glucoside, yielding on boiling 
with dilute acids a sugar. It is very poisonous ; 2 mgrms. will kill a dog of 12 kilos, 
weight in a few minutes, if subcutaneously injected ; but, taken by the stomach, it 
produces no effect.—Arnaud, Covipt. Rend., cvi. 1011-1014. 
