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:
Dec. 18, 1979
Filed:
Aug. 10, 1978
Applicant:
Inventors:
Robert J Schultz, Amherst, NY (US);
Fred W Starks, Kenmore, NY (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07F / ;
U.S. Cl.
CPC ...
2605025 ; 560171 ; 2605 / ;
Abstract
Improved methods for preparation of the tetrasodium and disodium salts of N-(phosphonoacetyl)-L-aspartic acid (PALA) are disclosed. The present methods are well suited for preparation of these products in large amounts. Particular aspects of these methods include: (1) initial preparation of the PALA moiety as the dibenzyl ester; (2) the complete removal of impurities in the form of acetic acid and sodium acetate from disodium PALA by turbulent flow precipitation; and (3) preparation and purification of the cyclohexylammonium salt of dibenzyl PALA which ultimately results in a purer final product.