p. 4125 - 4128
(1993)3-{4-[(Diethoxy-phosphoryl)-difluoro-methyl]-phenyl}-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionic acid
2-tert-Butoxycarbonylamino-3-{4-[(diethoxy-phosphoryl)-difluoro-methyl]-phenyl}-propionic acid methyl ester
2-tert-Butoxycarbonylamino-3-{4-[(diethoxy-phosphoryl)-difluoro-methyl]-phenyl}-propionic acid
2-tert-Butoxycarbonylamino-3-[4-(diethoxy-phosphoranecarbonyl)-phenyl]-propionic acid methyl ester
2-tert-Butoxycarbonylamino-3-{4-[(diethoxy-phosphoryl)-hydroxy-methyl]-phenyl}-propionic acid methyl ester