Preparation of (-)-5-(beta)-1-hydroxy-2-((beta)-1-methyl-3-phenylpropyl)aminoethyl) salicylamide
US4658060A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1982 |
| Grant date | Apr 14, 1987 |
| Priority date | — |
| Expiry date | Apr 26, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/55
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
There is disclosed a multistep process for producing (-)-5-[(R)-1-hydroxy-2-((R)-1-methyl-3-phenyl-propyl)aminoethyl]salicylami de in high yields which does not require chromatography. The process is stereoselective for the desired products starting with the reaction of D-(+)-alpha-methylbenzylamine with benzylacetone followed by reduction of the resulting Schiff's base to form an amine as an R,R: R,S diastereomeric mixture, resolution of the mixture to obtain the R,R stereoisomer as a salt, conversion to a free base, reaction of the R,R free base with an O-protected alpha-bromo-3-carbamoyl-acetophenone to produce the corresponding R,R-ketobenzamide, reduction to produce a mixture of S,R,R;R,R,R hydroxybenzamide, removal of the protecting groups, resolution of the deprotected product and then conversion to the free R,R-amine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.