Page 23 - phytochemistry general program

Classification of alkaloids

Alkaloids have been classified according to the following:

1- Biogenetic classification:

(biosynthetic pathway of production in the plant) .1
.2
Phenyl alanine (phenylalkylamine alkaloids) .3
.4
Tyrosine (Opium alkaloids) .5

Ornithine (Tropane alkaloids)

Tryptophan (Indole & Quinoline alkaloids )

2- The taxonomical origin classification:

In many cases different alkaloids obtained from the same plant have similar
chemical structure, e.g.Coca alkaloids, Atropa alkaloids, Rauwolfia alkaloids, ergot

alkaloids and so on.

3-The pharmacological action classification: e.g.CNS stimulant alkaloids; caffeine

4- Classification as amines: Classification as 1ry, 2ry, 3ry ,4ry alkaloids

5- Chemical classification:

Classification according to the nature of the basic chemical structure from which
they are derived.

According to chemical structure, two broad divisions may be recognized:

A- Non-heterocyclic or atypical alkaloids that are called “protoalkaloids” or .1
biological amines.

B- Heterocyclic or typical alkaloids, that are sub-classified into different .2
groups according to their ring structure.

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