Processes for making hydrazides
AssigneeWyeth
InventorsGeorge Anello Chiarello, Ayman Sahli
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Abstract
A method is disclosed for preparing hydrazides from hydrazine and an acyl chloride which comprises the steps of (a) preparing a stirred substantially uniform slurry comprising hydrazine and an inert solvent at low temperature; and (b) adding an acyl chloride continuously to said slurry. The method avoids or limits production of undesired bis-hydrazide by-products. The method is used to prepare 3-methyl-3-mercaptobutanoic acid hydrazide, a molecule used to link calicheamicin to a monoclonal antibody.
Claims25
A stirred, uniform slurry comprising hydrazine in an inert solvent, prepared by dropwise addition of the hydrazine to a cold inert solvent, wherein the volume ratio of hydrazine to the inert solvent is about 14% to about 19%, and wherein the inert solvent is selected from the group consisting of methylene chloride, carbon tetrachloride, chloroform, ethylene dichloride, chlorobenzene, and mixtures thereof.
Dependencies are inferred from the claim text.