Page 98 - phytochemistry II -pharmD general
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Imidazole alkaloids
The most important pharmaceutical examples of this group are Pilocarpus alkaloids.
Pilocarpine
pilocarpine finding use as an ophthalmic cholinergic drug.
Lactone of pilocarpic acid
(Pilocarpine)
Sources:
Pilocarpuse microphyllus & P. jaborandi (Rutaceae).
Physical properties:
➢ oily syrupy non-volatile liquid.
➢ Dextrorotatory.
➢ The base is easily soluble in H2O and CHCl3
Tests for identity:
➢ Helch’s test
Pilocarpine soln in H2O + Pot. dichromate + H2O2 + dil. acid violet color
Upon shaking with CHCl3 it will extract the violet color .
This color reaction can be used for Colorimetic estimation of pilocarpine
➢
➢ Nitrates of pilocarpine and isopilocarpine are separated by fractional
crystallization from ethanol.
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