(3R,5R)-5-(tert-Butyl-dimethyl-silanyloxy)-tetrahydro-pyridazine-1,2,3-tricarboxylic acid 1,2-di-tert-butyl ester 3-methyl ester

(3R,5R)-5-Hydroxy-hexahydro-pyridazine-3-carboxylic acid methyl ester

N-Troc-D-valine

(R)-2-(1,2-bis(tert-butoxycarbonyl)hydrazineyl)pent-4-enoic acid