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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)
1-Thujane derivatives:
Sabinene:
Occurrence: Oil of savin (Juniperus sabina)
1- Bicyclic monoterpenes have a tendency to undergo molecular rearrangement, shifting of
the double bonds may take place, oxidation, dehydrogenation and hydrogenation are likely.
2- Acid treatment open the rings
Sabinene is one of the chemical compounds that contributes to the spiciness of black
pepper
OH
Dehydration
OH
OH
Terpinene-4-ol Limonene Terpinene
Cold H SO
2
4 Hot H 2 SO 4
Hydration then Dehydration
Hydration
H +
Isomerisation
-thujene Sabinene
2-Pinane Derivatives
a-Pinene:
• Occurrence: In turpentine oil.
• Isolation & Purification:
• Isolation: by fractional distillation.
• Purification: by adding NOCl (nitrosyl chloride), where a-pinene is converted to
crystalline nitrosochloride, then recovered by the addition of aniline.
• Use: - highly repellant to insects
- substrate for many synthetic products such as borneol & camphor
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