Page 225 - PG 504-theoretical notes-phyto-1-2024-2025..

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

OH

OCH
3

CHO
• Ionones are used in synthesis of vitamin

B- Aromatic aldehydes 1- vanillin Vanillin
• Occurrence: clove oil, and some balsams.

• The most important source for vanillin is vanilla pods where it contains about 3%
vanillin which is present in a form of glucosides. By enzymatic hydrolysis these
glucosides release Vanillin and purified by sod. bisulfite method.

• Vanillin gives blue color with FeCl3.

• It is considered to be phenol and can be estimated either as aldehydes using the
bisulfite method or as phenol using alkali hydroxide method.

• Vanillin is widely used in flavoring, perfumery & cosmetics.
• Synthesis of Vanillin:

a) From eugenol
b) Oxidation of lignin give Vanillin (lignin looks like an iso eugenol polymer
OH
OCH OH
3 OCH 3
[O]

CHO
Vanillin
n
Lignin polymer
c) From guaiacol (application of Riemer Tiemann's reaction)

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