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:
Feb. 21, 2006
Filed:
Feb. 12, 2003
Quanlai Song, Encinitas, CA (US);
Bruce S. Ross, Carlsbad, CA (US);
Quanlai Song, Encinitas, CA (US);
Bruce S. Ross, Carlsbad, CA (US);
ISIS Pharmaceuticals, Inc., Carlsbad, CA (US);
Abstract
A process of manufacturing protected nucleosides comprises reacting a nucleoside with a protecting reagent in the presence of a regioselective activator to produce a regioselectively protected nucleoside. In some embodiments of the inventive method, an optionally substituted trityl or optionally substituted pixyl group is selectively added to the 5'-O-position of a nucleoside in the presence of lutidine as activator or activator/solvent. The inventive method results in improved selectivity of the 5′-O-position over the 3′-O-position, thereby improving overall product yield and purity, and permitting simplified purification protocols, in some cases obviating the need for chromatography to produce a purified protected nucleoside suitable for automated synthesis of oligonucleotides, such as primers, probes and antisense molecules.