(4S,5R)-4-Hydroxy-5-phenylethynyl-dihydro-furan-2-one

(E)-(S)-6-Oxo-8-phenyl-5-(tetrahydro-pyran-2-yloxy)-oct-2-en-7-ynoic acid tert-butyl ester

(R)-3-[(R)-2-tert-Butoxycarbonylamino-3-(4-methoxy-phenyl)-propionylamino]-2-methyl-propionic acid

(S)-2-{(R)-3-[(R)-2-tert-Butoxycarbonylamino-3-(4-methoxy-phenyl)-propionylamino]-2-methyl-propionyloxy}-4-methyl-pentanoic acid

(E)-(S)-5-Hydroxy-6-oxo-8-phenyl-oct-2-en-7-ynoic acid tert-butyl ester