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. 20, 2024
Filed:
Mar. 27, 2019
Nof Corporation, Tokyo, JP;
NOF CORPORATION, Tokyo, JP;
Abstract
A method for producing a multi-arm type polyethylene glycol derivative, which includes carrying out the following in order: Step (A): protecting an even number of hydroxyl groups, while leaving only the hydroxyl group at the 1-position of a polyhydric alcohol having an odd number of hydroxyl groups, other than the hydroxyl group at the 1-position by cyclic benzylidene acetalization, Step (B): linking two molecules of the compound obtained in step (A) to a compound for introducing a specific linker by etherification reaction, Step (C): deprotecting the cyclic benzylidene acetal structure at the terminal of the compound obtained in step (B), Step (D): polymerizing 3 to 600 mol of ethylene oxide to each hydroxyl group of the compound obtained in step (C) to obtain a multi-arm type polyethylene glycol derivative, and Step (E): functionalizing the hydroxyl group at the terminal of the multi-arm type polyethylene glycol derivative obtained in step (D).