L-Serine → Z-Glu(OBzl)-Ser-OH

Temperatur

-15 °C

To a solution of Z-Glu(OBzl)OH (5.62 g, 15 m mole) (Hayakawa et al. Bull. Chem. Soc. Japan, 39: 391 (1966)) in tetrahydrofuran (20 ml), N-methylmorpholin (1.53 ml) and isobutyl chloroformate (1.98 ml) were added with stirring at -15° C. To this mixture a solution of HOSu (N-hydroxy-succinimide) (3.45 g) in tetrahydrofuran (10 ml) was added with stirring at -15° C. The mixture was stirred at -15° C. for 30 min., and at 0° C. for 30 min. To this mixture a solution of H-Ser-OH (3.15 g, 30 mmole) in H2O (15 ml) containing triethylamine (4.2 ml) was added with stirring at 0° C. The mixture was stirred at 0° C. for 2 hr. and at room temperature for 15 hr. After removal of the organic solvent, the residue was extracted with three portions of ethyl acetate, which were washed successively with 1N citric acid and sat. NaCl solution, and dried over Na2SO4. After evaporating the residue was solidified by addition of ether. Reprecipitation from methanol-ether to yield (I) (5.29 g, 76.9%), RfI 0.74 RfII 0.70, mp 104°-105° C. [α]D27 +5.7 (C=1.12 in methanol).

1. stirringwith stirring at -15° C
2. stirringThe mixture was stirred at -15° C. for 30 min.
3. additionwas added
4. stirringwith stirring at 0° C
5. stirringThe mixture was stirred at 0° C. for 2 hr
6. waitand at room temperature for 15 hr
7. customAfter removal of the organic solvent
8. extractionthe residue was extracted with three portions of ethyl acetate, which
9. washwere washed successively with 1N citric acid and sat. NaCl solution
10. dry with materialdried over Na2SO4
11. customAfter evaporating the residue
12. additionwas solidified by addition of ether
13. customReprecipitation from methanol-ether

ORD-Eintrag

ord-759ebb41ab394f4cb105107fb97fa18c

Quelldatensatz

uspto-grants-1985_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04518527