Preparation of pyrrol and oxazole compounds: formation of porphyrins and c-acyl-.alpha.-amino acid esters therefrom
US5367084A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1993 |
| Grant date | Nov 22, 1994 |
| Priority date | — |
| Expiry date | Oct 26, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D207/34
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for preparation of new or previously known pyrrol derivatives is provided. The process involves reacting a nitroalkane or a nitroalkene with an isocyanoacetate in the presence of a proprophosphatrane "super base" to prepare the pyrrol compounds. Through production of new pyrrol compounds, new pyrrol derivatives such as dipyrromethane and porphyrin may be synthesized. In addition, the high yields of pyrrol compounds produced according to the method of the invention provide for more efficient production of previously known dipyrromethane and porphyrin compounds. The invention further provides a mild, high yield process for de-esterification of esterified pyrrol and dipyrromethane compounds. The invention also provides a synthetic method for the production of high yields of oxazoles through reaction of an aryl halide or acid anhydride with an isocyanoacetate in the presence of a prophosphatrane "super base". The product oxazoles serve as intermediates for subsequent treatment to provide pharmaceutically interesting C-acyl-.alpha.-amino acid esters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.