Thio salicylic acid

Sodium disulfide (or polysulflde) solution, Na S. For use in the preparation of thio-salicylic acid, the reagent is prepared by heating and stirring a mixture of 1.1 moles of Na2S-9H20, 290 ml. of water, and 1.1 moles of powdered sulfur until a brownish red solution results. A solution of 40 g. of sodium hydroxide in 100 ml. of water is added, and the solution is cooled in a salt-ice bath and stirred at 0-5° during addition of a solution of diazotized anthranilic acid. This Sandmeyer-type displacement gives a disulfide reducible to thiosalicylic acid. 

Piroxicam is a non-steroidal anti-iflammatory drug, of the oxicam class. A contact and photocontact sensitizer, which induced contact dermatitis in a physical therapist. Piroxicam generally cross reacts with thio-salicylic acid and also with thiomersal. Cross sensitivity is not observed to tenoxicam. 

Acyl isothiocyanates. The reaction of the reagent with carboxylic acids ves, as expected, acyl isothiocyanates, RCONCS, in 40-55%, yield. A more interesting example is the reaction with salicylic acid in CH2CI2 at — 40" to give 2-thio-3,4-dihydro-2fl-l,3-benzoxazine-4-one (1) in 70% yield. ... 

Caton-Williams et al7 reported a one-pot synthesis of nucleoside 5 -(a-P-thio) triphosphates (89) and phosphorothioate nucleic acids without protecting any nucleoside functionalities. The chemistry of this faeile synthesis involves the treatment of unprotected nucleosides with a mild phosphitylating reagent (salicyl phosphorochloridite and pyrophosphate) followed by sulfurization and hydrolysis to afford the corresponding analogues. These compounds can be easily purified by ion-exchange chromatography. 

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