Glycine → (S)-2-(2-((tert-Butoxycarbonyl)amino)-4-methylpentanamido)acetic acid

2.63 Grams of H-Gly-OH and 3.50 g of sodium hydrogen carbonate were suspended in 50 ml of water, to this supension was added, under ice-cooling condition, 50 ml of dioxane solution containing 10.0 g of Boc-Leu-OSu, and stirred for 30 minutes, then this mixture was further stirred at room temperature for 15 hours. The reaction mixture was concentrated under reduced pressure, and the residue thus obtained was extracted with ethyl acetate (70 ml). The ethyl acetate layer was washed with 1N-hydrochloric acid, and with a saturated sodium chloride aqueous solution, then was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue thus obtained was recrystalled from ethyl acetate-n-hexane to obtain 6.65 g (yield: 75.7%) of the above-mentioned objective product.

1. additionwas added, under ice-
2. stirringthis mixture was further stirred at room temperature for 15 hours
3. concentrationThe reaction mixture was concentrated under reduced pressure
4. customthe residue thus obtained
5. extractionwas extracted with ethyl acetate (70 ml)
6. washThe ethyl acetate layer was washed with 1N-hydrochloric acid
7. dry with materialwith a saturated sodium chloride aqueous solution, then was dried over anhydrous magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe residue thus obtained

ORD record

ord-e827f6e001ba444aab7a9df216915011

Source dataset

uspto-grants-1993_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05204326