Galanthamine N-Oxide → (-)-Galantamine

HRID 619015

Reaction equation

HRID 619015 reaction equation
[CH3:1][N+:2]1([O-])[CH2:18][C:16]2=[C:17]3[C:12](=[C:13]([O:19][CH3:20])[CH:14]=[CH:15]2)[O:11][C@@H:10]2[C@:5]3([CH:6]=[CH:7][C@H:8]([OH:21])[CH2:9]2)[CH2:4][CH2:3]1>CO>[CH3:1][N:2]1[CH2:18][C:16]2[CH:15]=[CH:14][C:13]([O:19][CH3:20])=[C:12]3[C:17]=2[C@:5]2([C@@H:10]([O:11]3)[CH2:9][C@@H:8]([OH:21])[CH:7]=[CH:6]2)[CH2:4][CH2:3]1

Participants

3

Reactant 1

HCID 11748698Galanthamine N-Oxide

Product 1

HCID 9651(-)-Galantamine

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of 1.73 g (5.7 mmoles) of galanthamine N-oxide and 3.17 g (11,4 mmoles, 2 eq) of FeSO4 --7H2O in 100ml of methanol is agitated under argon for 1.5 hours at 10° C. After the evaporation of the solvent, the residue is taken up again in dichloromethane, treated with a saturated aqueous solution of sodium hydrogencarbonate and extracted three times with dichloromethane. The organic phases are collected and washed with a saturated aqueous solution of sodium chloride, dried on sodium sulfate and evaporated. The crude product of the reaction is purified by flash chromatography on silica gel using the mixture of dichloromethane/methanol (80:20) as eluant. The least polar fraction yields galanthamine and the most polar fraction yields for the most part norgalanthamine in the form of a white foam (yield=76%).

Workup

  1. customAfter the evaporation of the solvent
  2. additiontreated with a saturated aqueous solution of sodium hydrogencarbonate
  3. extractionextracted three times with dichloromethane
  4. customThe organic phases are collected
  5. washwashed with a saturated aqueous solution of sodium chloride
  6. customdried on sodium sulfate
  7. customevaporated
  8. customThe crude product of the reaction is purified by flash chromatography on silica gel using
  9. additionthe mixture of dichloromethane/methanol (80:20) as eluant

Sources & evidence

ORD record
ord-0c1322a7f47645ad923f4c026698e788
Source dataset
uspto-grants-1999_09
Patent number
US05958903

Linked notes

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