Page 35 - phytochemistry II -pharmD general
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Piperidine ring alkaloids
• This group includes,lobelia, Conium and pomegranate alkaloids.
Lobelia alkaloid (Indian tobacco)
Lobeline
Source
Lobelia herb or Indian tobacco
Properties
Lobeline HCl is soluble in chloroform
Lobeline aqueous solution is unstable and should be used at once.
Separation ofLobeline from the mixture of total lobelia alkaloids
The residue of the total alkaloids is dissolved in hydrochloric acid (alkaloids
HCl) and extracted withchloroform,only LobelineHCl is extracted(soluble in
chloroform)
• Tests for identity of lobeline
• On the addition of few drops of Marqui’s reagent to few crystals of lobeline,
a red color is produced.
Uses
Galenical preparations of lobelia are used for their expectorant properties.
Lobeline is a respiratory stimulant.
0.5-1.5 mg doses of lobeline in lozenges or tablets are used to aid in
breaking the tobacco habit.
An injection of lobelin HCL is used in the resuscitation of new born infants who
fail to breathe after birth
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