反応 #6396

反応方程式

17-ethyl-1-hydroxy-12-[2'-(3",4"-dihydroxycyclohexyl)-1'-methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.04,9 ]octacos-18-ene-2,3,10,16-tetraone

isopropyl trichloroacetimidate

Trifluoromethanesulfonic acid

→

title compound

17-Ethyl-1-hydroxy-12-[2'-(4"-hydroxy-3"-isopropoxycyclohexyl)-1'-methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.04,9 ]octacos-18-ene-2,3,10,16-tetraone

反応条件

後処理

1. 1
   workup.ADDITIONto mix for 5 minutes
2. 2
   その他After 24 hours the reaction was quenched by the addition of saturated sodium bicarbonate
3. 3
   抽出extracted with ethyl acetate (3×8 ml)
4. 4
   洗浄The combined organics were washed with brine
5. 5
   乾燥dried over magnesium sulfate
6. 6
   その他Purification of the
7. 7
   濃縮concentrate by preparative TLC on silica gel (ethyl acetate:hexane (1:1)+1% methanol)

実験手順

To a solution of 17-ethyl-1-hydroxy-12-[2'-(3",4"-dihydroxycyclohexyl)-1'-methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.04,9 ]octacos-18-ene-2,3,10,16-tetraone (69 mg in 3 ml 33% methylene chloride in cyclohexane), isopropyl trichloroacetimidate (22 μl neat) was added and the reagents allowed to mix for 5 minutes. Trifluoromethanesulfonic acid (2μl neat) was added slowly via syringe and the mixture stirred at room temperature. After 24 hours the reaction was quenched by the addition of saturated sodium bicarbonate and extracted with ethyl acetate (3×8 ml). The combined organics were washed with brine and dried over magnesium sulfate. Purification of the concentrate by preparative TLC on silica gel (ethyl acetate:hexane (1:1)+1% methanol) gave the title compound (12 mg).

出典