반응 #54609

반응 방정식

Boc-Ser(Bzl)-Ser(Bzl)-Glu(OBzl)-OH

HCl

Boc-Thr(Bzl)-OSu

Et3N

Et3N

→

Boc-Thr(Bzl)-Ser(Bzl)-Ser(Bzl)-Glu(OBzl)-OH

용매

DMSO

THF

DMF

반응 조건

후처리

1. 1
   기타The mixture was evaporated to dryness
2. 2
   기타the residue evaporated twice more with THF
3. 3
   기타to give a solid mass (59.3 g; mp 161°-165°)
4. 4
   기타It was collected
5. 5
   세척washed with ether
6. 6
   온도to maintain
7. 7
   기타the reaction slightly basic
8. 8
   기타Some insoluble matter formed
9. 9
   여과was filtered off
10. 10
    기타the filtrate evaporated to an oil which
11. 11
    workup.DISSOLUTIONwas dissolved in EtOAc (1.5 liters)
12. 12
    세척washed with 5% HOAc, H2O (2 times)
13. 13
    건조dried (Na2SO4)
14. 14
    기타evaporated to a solid mass
15. 15
    기타The product was recrystallized from EtOAc and petroleum ether
16. 16
    기타to yield

실험 절차

Boc-Ser(Bzl)-Ser(Bzl)-Glu(OBzl)-OH (71.6 g, 104 mmol) was treated with 2.7 liters of freshly prepared 3.9 N HCl in THF for 45 minutes. The mixture was evaporated to dryness and the residue evaporated twice more with THF to give a solid mass (59.3 g; mp 161°-165°). It was collected and washed with ether and stirred in 500 ml of DMF with Boc-Thr(Bzl)-OSu (38.2 g, 94 mmol) in the presence of Et3N (25 ml) at 0° for 1 hour and then at 25° for 15 hours. More Et3N (14.5 ml) was added in serveral portions during this time to maintain the reaction slightly basic. Some insoluble matter formed was filtered off and the filtrate evaporated to an oil which was dissolved in EtOAc (1.5 liters), washed with 5% HOAc, H2O (2 times), dried (Na2SO4), and evaporated to a solid mass. The product was recrystallized from EtOAc and petroleum ether to yield, 64.8 g (78.1%); mp 115°-118°; [α]D25 =+11.64° (c 1, DMSO).

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