(S)-3-[3-(tert-Butyl-dimethyl-silanyloxy)-4-methoxy-5-methyl-phenyl]-2-[(9H-fluoren-9-ylmethoxycarbonyl)-methyl-amino]-propionic acid

(3S,4R)-3-Amino-1-benzyl-4-(5-hydroxy-2,4-dimethoxy-3-methyl-phenyl)-azetidin-2-one

(2aS,4R,8bR)-1-Benzyl-5-hydroxy-6,8-dimethoxy-7-methyl-2-oxo-1,2,2a,3,4,8b-hexahydro-1,3-diaza-cyclobuta[a]naphthalene-4-carboxylic acid methyl ester

(2aS,4S,8bR)-1-Benzyl-5-hydroxy-6,8-dimethoxy-7-methyl-2-oxo-1,2,2a,3,4,8b-hexahydro-1,3-diaza-cyclobuta[a]naphthalene-4-carboxylic acid methyl ester

(2aS,4R,8bR)-1-Benzyl-5-hydroxy-6,8-dimethoxy-7-methyl-2-oxo-2,2a,4,8b-tetrahydro-1H-1,3-diaza-cyclobuta[a]naphthalene-3,4-dicarboxylic acid 3-tert-butyl ester 4-methyl ester