Page 103 - phytochemistry II -pharmD general

solasodine demonstrates the close similarity to the structure of the steroidal
saponins. The following structures show that solasodine is exactly the N-
analogue of diosgenin, a steroidal sapogenin.

25 25

F F

E ON E OO

CD CD

A5 B HO A5 B
HO
Diosgenin
Solasodine (In Dioscoria & Trigonella species)
(The N-Analogues of Diosgenin)

Solanum alkaloids have no or little physiological activity. However they are
of great commercial value as starting material (precursors) for the synthesis of the
steroidal sex hormones and the corticoids.

2. Veratrum alkaloids

Veratrum species Fam. Liliaceae contain alkaloids of typical or atypical
steroidal structures; these alkaloids may be distinguished into two chemical types.
I)- The first type:

Includes simple typical or atypical steroidal alkamines. These alkamines
contain in their structure one or two hydroxyl groups but these hydroxyl groups are
not esterified by acids (not esters). They also have a double bond between C5
and C6.

From the formulas it is clear that some of these alkamines are typical steroids
(rubijervine and isorubijervine). While the others (jervine and veratramine) are
atypical steroids (they are C-Nor D-homo steroids).
These bases are found in plant extracts partly as free alkamines and partly as
glycosides (with one molecule of glucose at the OH of C3).

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