Page 36 - Phytochemistry 2 (06-PG 605)

Pyridone alkaloids

OCH3
CN

NO
CH3

Source: Castor seeds
The cake left after the expression of the oil contains about 0.2% ricinine.
Toxicity Ingestion causes nausea, vomiting, hemorrhagic gastroenteritis,
hepatic and renal damage. Also convulsions, coma, hypotension, respiratory
depression, and death.

Ricin (toxic protein): the main toxic principle of castor seeds

Quinoline alkaloids

Source: More than 25 alkaloids have been isolated from the bark of
Cinchona species , family Rubiaceae
• The 4 major alkaloids in cinchona are two pairs of stereo isomers :
(-) quinine, (+) quinidine,
• (-) cinchonidine and (+) cinchonine
• They occur in plant combined with some organic acids, chiefly quinic and
cinchotannic acids .

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