Réaction #81344

ord-47a2d8e4b8b645a482a9b6f8488878c1

Équation de réaction

CC(C)[C@H](NC(=O)OC(C)(C)C)C(=O)OC(O)C(=O)[C@@]1(O)CC[C@H]2[C@@H]3CCC4=CC(=O)CC[C@]4(C)[C@H]3[C@@H](O)C[C@@]21C
(2S)-2-((1,1-dimethylethoxycarbonyl) -amino)-3-methyl-butyric acid [11β,17,21-trihydroxy-3,20-dioxo -pregn-4-en-21-yl] ester
O=C(O)C(F)(F)F
trifluoroacetic acid
→
CC(C)[C@H](N)C(=O)OC(O)C(=O)[C@@]1(O)CC[C@H]2[C@@H]3CCC4=CC(=O)CC[C@]4(C)[C@H]3[C@@H](O)C[C@@]21C.O=C(O)C(F)(F)F
(2S)-2-amino-3-methyl-butyric acid [11β,17,21-trihydroxy-3,20-dioxo-pregn-4-en-21-yl] ester trifluoroacetate
Rendement 76.0%

Réactifs

CC(C)[C@H](NC(=O)OC(C)(C)C)C(=O)OC(O)C(=O)[C@@]1(O)CC[C@H]2[C@@H]3CCC4=CC(=O)CC[C@]4(C)[C@H]3[C@@H](O)C[C@@]21C
(2S)-2-((1,1-dimethylethoxycarbonyl) -amino)-3-methyl-butyric acid [11β,17,21-trihydroxy-3,20-dioxo -pregn-4-en-21-yl] ester
O=C(O)C(F)(F)F
trifluoroacetic acid

Réactifs

Aucun

Conditions de réaction

Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    AutreThen, the trifluoroacetic acid is evaporated in a vacuum
  2. 2
    workup.ADDITIONThe residue is mixed
  3. 3
    workup.STIRRINGwith stirring with a little diethyl ether
  4. 4
    Autrethe white precipitate that is produced
  5. 5
    Autredried

Mode opératoire

500 mg (0.89 mmol) of (2S)-2-((1,1-dimethylethoxycarbonyl) -amino)-3-methyl-butyric acid [11β,17,21-trihydroxy-3,20-dioxo -pregn-4-en-21-yl] ester (Example 27) is mixed with 1 ml of trifluoroacetic acid and stirred for 10 minutes at room temperature. Then, the trifluoroacetic acid is evaporated in a vacuum. The residue is mixed with stirring with a little diethyl ether, the white precipitate that is produced is suctioned off and dried. 385 mg (76%) of (2S)-2-amino-3-methyl-butyric acid [11β,17,21-trihydroxy-3,20-dioxo-pregn-4-en-21-yl] ester trifluoroacetate is obtained.

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US05616573uspto-grants-1997_04