Oxy-4,4''-bis(benzenesulfinic acid sodium salt)

4,4''-Oxybis-benzenesulfinic Acid Disodium Salt is an intermediate used in the synthesis of 4,4''-Oxybis[p-(phenylsulfonylaniline)] Hydrochloride (O870561), which is used in the preparation of polyamido polysulfone thermoplastics.