Novel immunosuppressive butenamides
Abstract
2-[4-(1,1-Dimethylethyl)phenyl]thiophene 12 was carboxylated using butyllithium and carbon dioxide to give 5-[4-(1,1-dimethylethyl)phenyl]thiophene-2-carboxylic acid 13. Conversion of the acid 13 using diphenyl phosphazidate and triethylamine gave 5-[4-(1,1-dimethylethyl)phenyl]thiophene-2-carbonyl azide 14, which was rearranged in toluene at 110 °C with loss of nitrogen to give the isocyanate 15; this in turn was treated with sodium 1-cyanoprop-1-ene 2-oxide 16 in tetrahydrofuran to give 2-cyano-N-{5-[4-(1,1-dimethylethyl)phenyl]thiophen-2-yl}-3-hydroxybut-2-enamide 17. Analogous chemistry has been utilised to synthesize both phenylheteroarylbutenamides and phenylbutenamides which display immunosuppressive activity towards proliferating concanavalin A-stimulated T-lymphocytes.