1-((2S,3S)-3-(benzyloxy)piperidin-2-yl)propan-2-one

(4S,5S)-5-(benzyloxy)-8-hydroxy-4-((2-methoxyphenyl)amino)octan-2-one

(4S,5S)-5-(benzyloxy)-8-((tert-butyldimethylsilyl)oxy)-4-((2-methoxyphenyl)amino)octan-2-one

(2S,3S)-tert-butyl 3-(benzyloxy)-2-(2-oxo-3-(4-oxoquinazolin-3(4H)-yl)propyl)piperidine-1-carboxylate

tert-butyl (2S,3S)-3-(benzyloxy)-2-(3-bromo-2-oxopropyl)piperidine-1-carboxylate