Page 74 - Phytochemistry 2 (06-PG 605)
P. 74
Ecgonine
Me
NH
COOH
OH
H
Ecgonine
Ecgonine is tropine 2-carboxylic acid. It contains four
asymmetric carbon atoms consequently a number of optically
active stereoisomeric forms are possible.
Ecgonine is obtained by hydrolysis of cocaine with alkali or
with HCl at 160oC.
Cocaine
Me COOMe
NH
O
HO
It is benzoylecgonine methyl ester. It occurs as
laevorotatory colorless prisms (m.p. 96-98 oC) with a bitter taste
followed by numbness; It is slightly volatile, sparingly soluble in
water, soluble in alcohol, ether, chloroform, petroleum ether and
benzene. Partial hydrolysis is affected by boiling with water to
give methanol and benzoyl ecgonine, while complete hydrolysis by
alkali, or when heated with dil. hydrochloric acid at 160 oC, yield
ecgonine, benzoic acid and methanol.
hydrolysis
Cocaine → ecgonine + benzoic acid + methanol
Cocaine HCl
It is the official salt in B.P. 2008 and E.P. 84. Cocaine HCl is
readily soluble in water (1:0.5), alcohol, chloroform (1:15) but
insoluble in ether or petroleum ether.
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