Reacción #2346

ord-b36ff282a19946cb9e1721c4f32fd0ac

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    workup.STIRRINGThe mixture was stirred at room temperature for 2 hours
  2. 2
    Temperaturaheated
  3. 3
    Temperaturaat gentle reflux for 21/2 hours
  4. 4
    Otroevaporated
  5. 5
    workup.ADDITIONThe residue was treated with water
  6. 6
    OtroThe gum which precipitated
  7. 7
    Otrowas separated
  8. 8
    Extracciónextracted with dichloromethane, (2×50 ml)
  9. 9
    LavadoThe combined extracts were washed with brine
  10. 10
    Otrodried
  11. 11
    Otroevaporated
  12. 12
    OtroThe residue was purified by chromatography
  13. 13
    LavadoMega Bond Elut silica gel column, eluting with 5% methanol/dichloromethane/0.5% triethylamine

Procedimiento

A crude sample of the product of Example 36 (3.4 g) was treated with a solution, at 0° C., made by adding thionyl chloride (2.25 g) dropwise to ethanol (45 ml) with stirring at below 0° C. The mixture was stirred at room temperature for 2 hours, heated at gentle reflux for 21/2 hours, and evaporated. The residue was treated with water and adjusted to pH6 with aqueous sodium bicarbonate solution. The gum which precipitated was separated and the aqueous solution was adjusted to pH8 and extracted with dichloromethane, (2×50 ml). The combined extracts were washed with brine, dried and evaporated. The residue was purified by chromatography using a 10 g. Mega Bond Elut silica gel column, eluting with 5% methanol/dichloromethane/0.5% triethylamine to give the title product as a solid (0.2 g); m.p. 163°-165° C.; NMR(CDCl3) δ 8.34(2H,m), 7.97(2H,m), 6.98(2H,m), 6.63(2H,m), 4.89(2H,s), 4.7(2H,s), 4.29(2H,q), 4.1(2H,s), 3.7(2H, m), 3.6(2H,m), 1.31(3H,t); m/e 398(M+H)+ ; calculated for C21H23N3 O5 : C, 63.5; M, 5.83; N, 10.6. Found: C, 61.5; H, 5.9; N, 10.5%.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US05728701uspto-grants-1998_03