Réaction #2346
ord-b36ff282a19946cb9e1721c4f32fd0ac
Équation de réaction
Réactifs
Réactifs
Conditions de réaction
Traitement
- 1workup.STIRRINGThe mixture was stirred at room temperature for 2 hours
- 2Températureheated
- 3Températureat gentle reflux for 21/2 hours
- 4Autreevaporated
- 5workup.ADDITIONThe residue was treated with water
- 6AutreThe gum which precipitated
- 7Autrewas separated
- 8Extractionextracted with dichloromethane, (2×50 ml)
- 9LavageThe combined extracts were washed with brine
- 10Autredried
- 11Autreevaporated
- 12AutreThe residue was purified by chromatography
- 13LavageMega Bond Elut silica gel column, eluting with 5% methanol/dichloromethane/0.5% triethylamine
Mode opératoire
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%.