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:
Jan. 04, 2011
Filed:
Oct. 01, 2009
Torfinn Haaland, Spangereid, NO;
Ole Magne Homestad, Spangereid, NO;
Torfinn Haaland, Spangereid, NO;
Ole Magne Homestad, Spangereid, NO;
GE Healthcare AS, Oslo, NO;
Abstract
This invention relates generally to the preparation of non-ionic X-ray contrast agents, iohexyl, ioversol, and iodixanol. It further relates to a method for improving the purity of 5-amino-N,N'-bis(2,3-dihydroxypropyl)-isophthalamide (or ABA), an intermediate in the industrial preparation of these non-ionic X-ray contrast agents. In particular, it relates to a method for significantly removing ABA monomethylester and ABA dimer from ABA by hydrolyzing ABA under a pH between about 12 to about 13 in an aqueous medium to convert ABA monomethylester to ABA monoacid, before the iodination reaction of ABA.