Use of thiopropyl sepharose for preparation of 2-nitro-5-thiobenzoic acid

A simple method is described for preparation of 2-nitro-5-thiobenzoic acid (NTB), a compound with versatile applications but is commercially unavailab le. In this method, NTB is produced by the reduction of 5,5'-dithiobis(2-ni trobenzoic acid) (DTNB) with thiopropyl sepharose, which is then separated from NTB by filtration. Two molecules of NTB can be generated from each mol ecule of DTNB when a large excess of thiopropyl sepharose is used. Thioprop yl sepharose is commercially available and can be readily regenerated for r epeated use in the preparation of NTB, This method is simple and more effec tive than any other reported methods of NTB preparation. (C) 2000 Elsevier Science B.V. All rights reserved.