Process for the preparation of 6-(3,4-dihydro-3-oxo-1,4(2H)-benzoxazin-7-yl)-2,3,4,5-tetrahydropyridazin-3-ones
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jun 22, 1993
Grant Date -
N/A
app pub date -
Dec 21, 1990
filing date -
Dec 21, 1990
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
The invention relates to a process for the synthesis of compounds of the formula I ##STR1## wherein R.sub.1 -R.sub.5 are as defined herein. The process is a multistep process which comprises acylating a 2-benzoxazolinone with an alkanoic anhydride to form an acylated carbamate, hydrolyzing the carbamate, reacting the resultant aminophenol with haloalkanoyl halide to form a substituted benzoxazine, reacting the benzoxazine with an aldehyde, alkylating the resultant aminomethyl compound with an alkylating agent to form a quaternary ammonium salt, reacting the salt with an alkali metal cyanide to form a nitrile, hydrolyzing the nitrile and reacting the resultant carboxylic acid with hydrazine. The compounds are useful as cardiotonic and vasodilating agents and as inhibitors of phosphodiesterase fraction III and platelet aggregation. In addition, the compounds are active as smooth muscle relaxants and bronchodilators.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully