(2S,4R)-1-(tert-Butoxycarbonyl)-4-((2-(4-isopropoxyphenyl)benzofuro[3,2-d]pyrimidin-4-yl)oxy)pyrrolidine-2-carboxylic acid (cas# 1315326-78-3) is a useful research chemical, used in the preparation of proline-containing peptidomimetics as HCV protease inhibitors.