The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 22, 2005
Filed:
Feb. 25, 2003
Marioara Mendelovici, Rehovot, IL;
Gideon Pilarsky, Holon, IL;
Tamar Nidam, Yehud, IL;
Ben-zion Dolitzky, Petach Tikva, IL;
Marioara Mendelovici, Rehovot, IL;
Gideon Pilarsky, Holon, IL;
Tamar Nidam, Yehud, IL;
Ben-Zion Dolitzky, Petach Tikva, IL;
Teva Pharmaceutical Industries Ltd., Petah Tiqva, IL;
Abstract
A process for preparing 6-hydroxy-3,4-dihydroquinolinone by intramolecular Friedel-Crafts alkylation of N-(4-methoxyphenyl)-3-chloropropionamide in which an equivalent of N-(4-methoxyphenyl)-3-chloropropionamide is contacted with a Lewis acid in DMSO or a high boiling amide or amine at an elevated temperature of from about 150° C. to about 220° C. is provided. The process produces 6-HQ in high yield and a high state of purity such that it may be used in subsequent reactions toward the preparation of cilostazol without intermediate purification. A process for preparing cilostazol from 6-hydroxy-3,4-dihydroquinolinone prepared by the process and improved processes for preparing N-(4-methoxyphenyl)-3-chloropropionamide are also provided.