potassium cyanide
(R,S)-ethyl 4-<(tert-butoxycarbonyl)amino>-4,5-dihydro-3-<(diphenoxyphosphinyl)oxy>-2-thiophenecarboxylate
phosphoric acid diphenyl ester chloride
(R,S)-N-(tert-butoxycarbonyl)-S-(carbethoxymethyl)-cysteine, ethyl ester
(R,S)-ethyl 4-<(tert-butoxycarbonyl)amino>tetrahydro-3-oxo-2-thiophenecarboxylate