Page 67 - phytochemistry II -pharmD general

Ecgonine is pseudotropine 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.

Alkaloids from ecgonine base:

1. Cocaine
2. Cinnamyl cocaine

It occurs in Java coca leaves in a percentage higher than that of cocaine as
rosettes or needles, m.p.121 oC, insoluble in water, soluble in organic solvents.
The platinic chloride of cinnamyl cocaine is amorphous (c.f. cocaine). When
heated with hydrochloric acid, cinnamyl cocaine yields ecgonine, cinnamic acid
and methyl alcohol. It reduces acid potassium permanganate solution on cold.

3. Truxillines
They are esters of methyl ecgonine with α or β-truxillic acid. Truxillic acids

are dimers of cinnamic acid. Solutions of the base are laevorotatory.

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.

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