Process for the preparation of 4-(8-chloro-5 6-dihydro-11h-benzo-(5 6)-cyclohepta-(1 2b)-pyridin-11-ylidene-1-piperidiniecarboxylic acid ethyl ester (loratadine)
US7449583B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 2002 |
| Grant date | Nov 11, 2008 |
| Priority date | — |
| Expiry date | Apr 30, 2024 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D413/14
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process and new oxazolinic intermediates for the preparation of 4-(8-chloro-5,6-dihydro-11H-benzo-[5,6]-cyclohepta-[1,2-b]-pyridin-11-ylidene)-1-piperidinecarboxylic acid ethyl ester (loratadine) is described. The process starts from 2-(4,4-dimethyl-4,5-dihydrooxazol-2-yl)-3-methyl-pyridine, a new intermediate to obtain loratadine. 2-(4,4-dimethyl-4, 5-dihydrooxazol-2-yl)-3-methyl-pyridine is condensed with 3-chloro-benzyl-chloride and the resultant product is treated with Grignard reagent of 4-chloro-N-methyl-piperidine. [3-(2-(3-chloro-phenyl)-ethyl]-pyridin-2-yl]-1-(methyl-piperidin-4-yl)-methanone is obtained for subsequent hydrolysis. Starting from this last compound it is possible to obtain loratadine with known methods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.