Sulfamic Acid → 2-Methyl-2-[3-(3-{4-[7-(2-morpholin-4-yl-ethoxy)-benzo[d]imidazo[2,1-b]thiazol-2-yl]-phenyl}-ureido)-isoxazol-5-yl]-propionic acid

Participants

Reaction Steps

Alternatively final compound 2-methyl-2-[3-(3-{4-[7-(2-morpholin-4-yl-ethoxy)-benzo[d]imidazo[2,1-b]thiazol-2-yl]-phenyl}-ureido)-isoxazol-5-yl]-propionic acid (I-5) is prepared by following a general procedure given in US 2005/0070549 A1. To a stirred solution of 1-[5-(1,1-dimethyl-2-oxo-ethyl)-isoxazol-3-yl]-3-{4-[7-(2-morpholin-4-yl-ethoxy)-benzo[d]imidazo[2,1-b]thiazol-2-yl]-phenyl}-urea (I-4a) (1 equivalent) in a mixture of acetic acid and water at rt is added a solution of amidosulfuric acid (1.5 equivalents) and sodium chlorite (1.5 equivalents) in water, and the mixture is stirred at rt until the reaction is substantially complete as monitored by LCMS or TLC. The mixture is neutralized with 30% aq sodium hydroxide and partitioned between water and either dichloromethane or a mixture of isopropanol and dichloromethane. The separated aqueous layer is further extracted with dichloromethane or a mixture of isopropanol and dichloromethane, and the combined organic layers are washed with water or brine dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The residue is purified by preparative reverse-phase HPLC or silica gel flash chromatography to afford 2-methyl-2-[3-(3-{4-[7-(2-morpholin-4-yl-ethoxy)-benzo[d]imidazo[2,1-b]thiazol-2-yl]-phenyl}-ureido)-isoxazol-5-yl]-propionic acid (I-5).

Provenance & Evidence