(1S,8aS)-1-((R)-1-Hydroxy-but-2-ynyl)-6-triisopropylsilanyl-8,8a-dihydro-1H-oxazolo[3,4-a]pyridine-3,7-dione

(1S,8aS)-1-[(S)-1-(tert-Butyl-dimethyl-silanyloxy)-but-2-ynyl]-8,8a-dihydro-1H-oxazolo[3,4-a]pyridine-3,7-dione

Formic acid (S)-1-((1S,8aS)-3,7-dioxo-6-triisopropylsilanyl-1,7,8,8a-tetrahydro-oxazolo[3,4-a]pyridin-1-yl)-but-2-ynyl ester

(S)-2-[(S)-Hydroxy-(methoxy-methyl-carbamoyl)-methyl]-4-oxo-5-triisopropylsilanyl-3,4-dihydro-2H-pyridine-1-carboxylic acid (1R,2S)-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester

(S)-2-((S)-2,2-Diethyl-5-oxo-[1,3]dioxolan-4-yl)-4-oxo-5-triisopropylsilanyl-3,4-dihydro-2H-pyridine-1-carboxylic acid (1R,2S)-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester