Methods for the preparation of charged crosslinkers

摘要

Processes for the preparation of charged crosslinkers bearing a sulfonic acid moiety are disclosed. These procedures also optionally include methods to convert the resulting products to substantially a single salt form.

主权项

1. A process for the preparation of a compound of formula (3): or a salt thereof, comprising the step of: a) reacting a lactone of formula (4): with a sulfonating agent to form a compound of formula (5):or a salt thereof;
b) reacting the compound of formula (5) or a salt thereof with a sulfur-bearing nucleophile, optionally followed by deprotection, to form a compound of formula (6):or a salt thereof;
c) reacting the compound of formula (6) or a salt thereof with a disulfide compound to form the compound of formula (3), wherein: Q′ is a linear, branched or cyclic alkyl having 1 to 10 carbon atoms, phenyl, ortho or para-nitrophenyl, dinitrophenyl, pyridyl or nitropyridyl; and Ra, Rb, Rc, Rd and Re, each independently, is H or a linear, branched or cyclic alkyl having 1 to 10 carbon atoms.