Process for the preparation of 9-deoxo-8a-aza-(8a-alkyl)-8a-homoerythromycin A derivatives from 9-deoxo-9 (Z)-hydroxyiminoerythromycin A
US6482931B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 2001 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Mar 22, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07H17/08
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention provides a process for the preparation of 9-deoxo-8a-aza-8a-homoerythromycin A and of its 8a-alkylated derivatives from 9-deoxo-9(Z)-hydroxyiminoerythromycin A via a stereospecific Beckmann rearrangement in a reaction mixture using pyridine as main solvent, resulting in imidate intermediates which are not isolated from said mixture and which are employed directly in a reduction stage using a sufficient amount of borohydride, after extraction of the pyridine with a hydrocarbon which is miscible with the latter and in which said imidates are insoluble. The compound V can be directly N-alkylated at the 8a-position using an aldehyde without being isolated from the reduction mixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.