Synthesis and reactions of nitroso sulphamethoxazole with biological nucleophiles: Implications for immune mediated toxicity

Sulphamethoxazole hydroxylamine (SMX-NHOH) and nitroso sulphamethoxazole (SMX-NO) were prepared bv a modified literature procedure. SMX-NO produced a complex set of unstable intermediates with sulphur nucleophiles, but did not react with amino containing compounds. No reactions were observed between sulphamethoxazole (SMX) / SMX-NHOH and the nucleophiles used in this study. Thus antigens formed from N-oxidation of SMX are likely to be unstable in vivo.