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:
Apr. 06, 1993
Filed:
Jan. 03, 1992
Applicant:
Inventor:
Ponnampalam Mathiaparanam, Appleton, WI (US);
Assignee:
Appleton Papers Inc., Appleton, WI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ; C07D / ;
U.S. Cl.
CPC ...
544144 ; 544143 ; 546165 ; 546 94 ; 548427 ; 548456 ;
Abstract
Preparation of novel mono(indolylethylenyl) phthalides is disclosed. Specifically, these compounds are chromogenic mono(indolylethylenyl)phthalides of the formula ##STR1## wherein A is as hereinafter defined and selected from moieties of the type ##STR2## wherein L is an indole moiety as hereinafter defined; wherein B is a moiety of the type ##STR3## as hereinafter defined. The process disclosed comprises condensing indolylethylene with a keto acid or its derivative and an electron acceptor in an organic solvent.