Page 226 - PG 504-theoretical notes-phyto-1-2024-2025..

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

B- Aromatic aldehydes 2- cinnamaldehyde

• Occurrence: in cassia and cinnamon leaf and bark oils.
• Purification: by dilute and cold Sod. bisulfite, while recovering Cinnamaldehyd by
Na2CO3 solution. Hot and concentrated solution of NaHSO3 should be avoid
otherwise a soluble hydrosulfonic acid salt will be formed by the addition on the
ethylenic bond beside the normal aldehydic addition.
• Uses: flavoring, scenting and manufacture of artifical cinnamon flavor.
•
Heterocyclic Aldehydes

-FurFural -colorless liquid.

Source: pine oil, caraway and clove oils.
O CHO
It is water soluble

It occurs in the first fractions of most oils, these fractions are washed with water and the water
wash is extracted with ether Furfural can be purified by sodium bisulfite.

Furfural give a red color with aniline acetate and give the aldehydes reactions as bisulfite
addition, Br2 addition, and reduction of Fehling and Tollen’s

2- Terpene Ketones

A) Monocyclic

1- menthone
O
• Occurrence: in oil of Mentha

• Isolation: by hydroxylamine → oxime → dil H2SO4 → menthone

• Properties: colourless, oily liquid with mentha like odour Menthone
Br 2 /quinoline
• Reactions: (studied before) Menthone Thymol
Menthone Reduction Menthol

• Identification: by formation of oxime with definite m.p.

• Uses: in compounding artificial essential oils

2- Carvone

• Occurrence: in oil of caraway (Carum carvi)

• Isolation: By reaction with Na2SO3 to yield bisulfite derivatives: being ketone,
addition takes place at both ethylenic groups, the liberated NaOH is neutralized from
time to time with dil HCl, then extract the non-ketonic part with ether , treat with
NaOH to regenerate carvone which is distilled.

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