Z-D-GLU(OTBU)-OH

(R)-2-amino-5-(tert-butoxy)-5-oxopentanoic acid (1.00 g, 4.92 mmol) was suspended in THF (18.45ml)/Water (6.15 ml) and cooled to 0° C. using an ice bath. To the cold slurry was slowly added benzylchloroformate (0.773 mL, 5.41 mmol) and the reaction mixture was allowed to stir for 2.5 h. The slurry wasdiluted with 50 mL of EtOAc before being acidified to pH 3 using an aqueous 1N HCl solution. The crudeproduct was extracted three times with EtOAc. The organic phases were combined, dried over anhydroussodium sulfate, filtered and concentrated. The crude product was obtained as a clear oil and was subjected tosilica gel chromatography using 100percent Hexanes to 100percent ethyl acetate as eluant. The product, (R)-2-(((benzyloxy)carbonyl)amino)-5-(tert-butoxy)-5-oxopentanoic acid, was obtained as a colorless oil (1.41 g, 71percent). 1H NMR (400 MHz, chloroform-d) δ 7.44-7.29 (m, 5H), 5.53 (d, J=7.5 Hz, 1H), 5.13 (s, 2H), 4.41 (d, J=5.1 Hz, 1H), 2.56-2.30 (m, 2H), 2.21 (dd, J=13.5, 6.5 Hz, 1H), 2.06-1.88 (m, 2H), 1.45 (s, 9H).To a solution of 5-tert-butyl-L-glutamate (15 g, 76 mmol) in 110 mL of water and 50 mL of dioxane was added sodium carbonate (8.0 g, 76 mmol) followed by benzyl chloroformate (13 g, 76 mmol) in 60 mL of dioxane at 0°C for 3 hours. After stirring at room temperature overnight, the mixture was extracted with ethyl acetate (50 L*2) . The aqueous layer was acidified to pH 2 with 6N hydrochloric acid and extracted with ethyl acetate (50 mL*3) . The organic layer was washed with brine and dried over sodium sulfate, filtered and concentrated to give N-benzyloxycarbonyl-5- ert-butyl-L-glutamate (12 g, yield 47percent) as yellow oil. (1275)

Molecular Weight:337.4
XLogP3:2.2
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:6
Rotatable Bond Count:10
Exact Mass:337.15253745
Monoisotopic Mass:337.15253745
Topological Polar Surface Area:102
Heavy Atom Count:24
Complexity:437
Undefined Atom Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes