Page 176 - PG 504-theoretical notes-phyto-1-2024-2025..

Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

- The primary glycosides lanatoside A, is acted upon by specific enzymes (glucosidase enzyme)
which split the terminal glucose, giving the 2ry glycoside, acetyl digitoxin, which is
hydrolyzed by alkalis to digitoxin.

- Alkaline hydrolysis of the primary glycosides lanatoside A gives purpurea glycoside A which
gives digitoxin upon enzymatic hydrolysis.

- Digitoxin is hydrolyzed to digitoxigenin and 3 molecules of glucose by the action of acids

- Lanatoside A gives digitoxigenin and 3 molecules of glucose and one molecule of glucose
when hydrolyzed with acids.

Strophanthus glycosides

Several species of strophanthus (S. kombe and S. gratus, family Apocyanaceae) yield a group of
cardiac glycosides, the genins of which are very related chemically to those of the digitalis
glycosides, they differ only in having either - (CH 2 OH) or (CHO) group instead of the (CH 3 ) of C -
10.

Strophanthus kombe :

The seeds of Strophanthus kombe contains 8 - 10 % of a mixture of glycosides.

The principle glycosides are:

K-strophanthoside (a trioside),

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