270 POISONS : THEIR EFFECTS AND DETECTION. [§ 326 . 
disulphide, there is evolution of heat, separation of sulphur, and forma¬ 
tion of thiosulphate. Nicotine does not respond to this reaction. 
§ 326. The Constitution of the Coniine Bases. — Coniine is the 
dextro-modification of a -propylpiperidine, 
H 2 C 
ch 2 
^ ch 2 
h 2 c 
ch-ch 2 -ch 2 -cii 2 
N 
H 
Coniine. 
If the hydrochloride is distilled with zinc dust conyrine or a-propl- 
pyridine is formed, 
/X 
C 4 H 7 
N 
Conyrine. 
The coniceines are a-propylpiperidines. Five isomers have been 
prepared, of which a-coniceine and y-coniceine are more poisonous 
than coniine. 
a-coniceine is a liquid which boils at 158°. y-coniceine occurs in 
Conium maculatum and also in commercial coniine ; it is a liquid boiling 
at 171°-172°, optically inactive, and reduced by tin and HC1 or sodium 
and alcohol to inactive coniine, 
OH, 
H 2 C 
/ 
CH 
H 2 C ^ C—C 3 H 7 
N 
H 
y-Coniceine. 
Conhydrine is found in Conium maculatum. Crystallises from ether 
in colourless leaflets. Melts at 105°. Distils at 236°. Soluble in alcohol 
and in ether. Polarises to the right. It is an hydroxylated coniine, 
and may be provisionally represented thus— 
H 
OH 
: 2 c 
A 
ch 2 
: 2 c 
\/ 
-ch-c 3 h 7 
N' 
H 
Pseudoconhydrine is isomeric with conhydrine and has similar pro¬ 
perties. It is a crystalline deliquescent powder, soluble in water, 
