Page 147 - PG 504-theoretical notes-phyto-1-2024-2025..

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

Preparation of vanillin:

- 1 From Coniferin and Lignin

- 2 From Eugenol

CH -CH=CH 2 CH=CH-CH 3 OH
2

KOH
OCH OCH OCH
3 3 3
OH OH OH

Eugenol Isoeugenol Vanillin
The bulk of vanillin which is produced commercially is prepared from lignin, which gives upon
hydrolysis coniferyl alcohol. Lignin is obtained in extremely large amounts, as a by-product of
timber industry

Cyanogenetic Glycosides Ex.: Amygdalin

Mandelonitrile Gentiobioside

These are glycosides that yield hydrocyanic acid as one of their hydrolytic products.

Amygdalin

Amygdalin is the most widely distributed cyanophore glycoside.

It occurs in Prunus species, and is obtained from bitter almonds, apples seed, Amygdali n , has
anti - cancer effect .

It is a gentiobioside of mandelonitrile. Gentiobiose is a reducing disaccharide consisting of two
molecules of -glucose linked by -1,6 linkage.

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