Back to results
US 2014/0275551 A1Published application
Process for the preparation of roflumilast
AssigneeMylan Laboratories Limited
InventorsPriyesh VIJAYKAR, Dattatrey Kokane, Sushant Gharat, Dhananjay Shinde, Manojkumar Bindu, Vinayak Gore
Life of this patent
Estimating the term…
Abstract
The present invention relates to an improved process for the preparation of Roflumilast. The present invention also relates to crystalline Form-I of Roflumilast.
Claims9
A process for the preparation of Roflumilast comprising the steps of:
- a) reacting 4-Difluoromethoxy-3-hydroxy benzaldehyde of Formula II with a cyclopropylmethyl compound of Formula III in the presence of an organic base to obtain 3-cyclopropylmethoxy-4-Difluoromethoxy benzaldehyde of Formula IV
- wherein X is a leaving group,
- b) oxidising the obtained aldehyde compound of Formula IV into 3-cyclopropylmethoxy-4-Difluoromethoxy benzoic acid of Formula V,
- c) converting 3-cyclopropylmethoxy-4-Difluoromethoxy benzoic acid of Formula V to its acid halide and condensing with 4-amino 3,5-Dichloropyridine in the presence of base to obtain Roflumilast, and
- d) optionally purifying Roflumilast in an organic solvent to get pure Roflumilast.
2 more elements
Dependencies are inferred from the claim text.