Patent ID: 6448401
Filing Date: 2002-09-10
Classification: C07F

Abstract:
A process for the preparation of a water-soluble prodrug of the formula wherein A is and R and R1 are each independently hydrogen or (C1-C6)alkyl, or a pharmaceutically acceptable salt thereof, which comprises(a) reacting a compound of the formula Aâ€”OH wherein A is as defined above with a compound of the formula in which R and R1 are as defined above and Pr represents a hydroxyl-protecting group with a source of iodide ion selected from sodium iodide, lithium iodide, cesium iodide, cadmium iodide, cobalt iodide, copper iodide, rubidium iodide, barium iodide, zinc iodide, calcium iodide or elemental iodine in an inert organic solvent and in the presence of base at a temperature of from about 25Â° C. to 50Â° C. to form an intermediate of the formula wherein Pr, A, R and R1 are as defined above, and(b) removing the protecting groups Pr from intermediate IV to produce a compound of the formula and, optionally, converting said compound I to a pharmaceutically acceptable salt thereof.