Process for preparing 1,4-dihydro-4-oxoquinoline-2-carboxylates and 4-aminoquinoline compounds therefrom
US10875831B1 · kind B1 · utility
0Cited by
1References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 12, 2019 |
| Grant date | Dec 29, 2020 |
| Priority date | — |
| Expiry date | Aug 12, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D215/48
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method for preparing an alkyl 5,7-dihalo-1,4-dihydro-4-oxoquinoline-2-carboxylate ester is described herein. The method comprises cyclizing a compound of Formula III with Eaton's reagent in heated continuous flow reactor to form a compound of Formula IV wherein in Formula III and Formula IV, each X independently is a halogen atom; and each R independently is C1 to C4 alkyl. Optionally, a cosolvent such as dichloromethane can be included with the Eaton's reagent. A method of preparing a diphenylureido-dihalokynurenic acid alkyl ester of Formula VI from the compound of Formula IV also is described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.