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:
Oct. 20, 1992
Filed:
Jan. 18, 1991
Applicant:
Inventors:
David L Hughes, Old Bridge, NJ (US);
Dalian Zhao, Scotch Plains, NJ (US);
Assignee:
Merck & Co., Inc., Rahway, NJ (US);
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
546176 ; 546178 ; 548502 ;
Abstract
An indole having the formula I: ##STR1## is prepared by a Fischer-Indole reaction employing a mixture of phosphorous pentoxide and methane sulfonic acid as an acid catalyst. The reaction, which is optionally run in a co-solvent, provides 3-unsubstituted indoles in high yields with high regioselectivity. The indole thus prepared is an intermediate in the synthesis of leukotriene biosynthesis inhibitors.