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. 24, 1981
Filed:
Sep. 10, 1980
Takeda Chemical Industries, Ltd., Osaka, JP;
Abstract
Novel 1-azaxanthone-3-carboxylic acid derivatives, which are shown by the following formula (I) ##STR1## wherein R is hydrogen, alkyl, alkoxy or halogen; R.sub.1 and R.sub.2 are the same or different and each is hydrogen, alkyl or alkenyl; and m is 1 or 2; and their physiologically acceptable salts, are usable as effective medicines for preventing and/or treating allergic diseases. The compound of the formula (I) can be produced by reacting a compound of the formula: ##STR2## wherein R and m have the same meaning as defined above; R.sub.3 is carboxyl or group which is convertible into carboxyl through hydrolysis; X is alkyl phosphate radical or halogen, with a compound of the formula: ##STR3## wherein R.sub.1 and R.sub.2 have the same meaning as defined above, or its salt, and conducting hydrolysis, if necessary.