di-tert-butyl 1-((4R)-5-bromo-4-((tert-butyldimethylsilyl)oxy)-1-methoxy-1-oxopentan-2-yl)hydrazine-1,2-dicarboxylate

(3R,5R)-5-Hydroxy-tetrahydro-pyridazine-1,3-dicarboxylic acid 3-methyl ester 1-(2-trimethylsilanyl-ethyl) ester

(3S,5R)-5-Hydroxy-tetrahydro-pyridazine-1,2,3-tricarboxylic acid 1,2-di-tert-butyl ester 3-methyl ester

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