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:
Feb. 27, 1990
Filed:
Feb. 29, 1988
Terry G Sinay, Jr, Preston, CT (US);
Robert J Sysko, Niantic, CT (US);
Pfizer Inc., New York, NY (US);
Abstract
This invention relates to a process for the production of phthalazineacetic acid ester derivatives of the formula ##STR1## wherein R is (C.sub.1 -C.sub.4) alkyl which comprises reacting (Z)-3-oxo-1(3H)-isobenzofuranylideneacetic acid with hydrazine in the presence of a solvent; reacting the resulting mixture of the novel compound 1-hydrazino-1,2,3,4-tetrahydro-4-oxo-phthalazineacetic acid and 3,4-dihydro-4-oxo-phthalazineacetic acid with acid in the presence of a solvent; and reacting the resulting 3,4-dihydro-4-oxo-phthalazineacetic acid with acid in the presence of an alcohol. This invention also relates to the novel compound 1-hydrazino-1,2,3,4-tetrahydro-4-oxo-phthalazineacetic acid of the formula ##STR2## which is an intermediate formed in the process of this invention and which is useful for the production of phthalazineacetic acid ester derivatives of formula IV. The compounds of formula IV are useful for the preparation of certain heterocyclic oxophthalazinyl acetic acids and esters thereof.