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. 15, 1981
Filed:
Mar. 25, 1980
James A Ellard, Dayton, OH (US);
Joseph Satanek, Jr, Dayton, OH (US);
Other;
Abstract
In a method of preparing methotrexate from a coupling of 2,4-bis(triphenylphosphazino)-6-bromomethylpteridine hydrobromide with ethyl N-(p-methylamino)-benzoyl-L-glutamate to produce the phosphazino derivative of methotrexate ester and subsequently hydrolyzing the phosphazino and ester groups to produce the free methotrexate, the pteridine synthesis step wherein molecular oxygen is substituted for reaction air and the pH throughout the pteridine synthesis is regulated to between 2.5 and 5.4, the preferred pH being about 3.0 and producing from tetraaminopyrimidine and dihydroxyacetone the isomer 2,4-diamino-6-hydroxymethylpteridine over 2,4-diamino-7-hydroxymethylpteridine in a ratio of about 20:1. Exemplary of other situations involving pteridine where the molecular oxygen may be substituted for reaction air are: in the production of folic acid, tetrahydrofolic acid, etc.