2-Methylpiperazine → Gatifloxacin

HRID 492109

Reaction equation

HRID 492109 reaction equation
[CH:1]1([N:4]2[C:13]3[C:8](=[CH:9][C:10]([F:17])=[C:11](F)[C:12]=3[O:14][CH3:15])[C:7](=[O:18])[C:6]([C:19]([OH:21])=[O:20])=[CH:5]2)[CH2:3][CH2:2]1.[CH3:22][CH:23]1[CH2:28][NH:27][CH2:26][CH2:25][NH:24]1>CS(C)=O>[CH3:22][CH:23]1[NH:24][CH2:25][CH2:26][N:27]([C:11]2[C:12]([O:14][CH3:15])=[C:13]3[N:4]([CH:1]4[CH2:3][CH2:2]4)[CH:5]=[C:6]([C:19]([OH:21])=[O:20])[C:7](=[O:18])[C:8]3=[CH:9][C:10]=2[F:17])[CH2:28]1

Participants

4

Reactant 2

HCID 660572-MethylpiperazineHCID 70194651-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid

Product 1

HCID 5379GatifloxacinYield 75%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent2×

Conditions

Temperature
55 °C

Procedure

Forty grams of 1-cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinoline carboxylic acid and 28.4 g (2.1 eq) of 2-methyl piperazine were put in suspension in DMSO (800 mL) under nitrogen atmosphere. The mixture was heated to 55° C. during 24 hours. Subsequently, the mixture was heated to 70° C. and half of the amount of DMSO was distilled-off at reduced pressure (1-5 mm Hg). At the end of the distillation, toluene (200 mL) was added, the reaction mixture was cooled to 5° C., and held at this temperature overnight. The solution was filtered and dried under vacuum to obtain 38 g after assay (75% yield) of gatifloxacin.

Workup

  1. temperatureSubsequently, the mixture was heated to 70° C.
  2. distillationAt the end of the distillation, toluene (200 mL)
  3. additionwas added
  4. temperaturethe reaction mixture was cooled to 5° C.
  5. customheld at this temperature overnight
  6. filtrationThe solution was filtered
  7. customdried under vacuum

Sources & evidence

ORD record
ord-67e8ed0ba11d4a1cb5562f304898781a
Source dataset
uspto-grants-2009_05
Patent number
US07531656B2

Linked notes

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