반응 #6396

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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

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후처리

1. 1
   workup.ADDITIONto mix for 5 minutes
2. 2
   기타After 24 hours the reaction was quenched by the addition of saturated sodium bicarbonate
3. 3
   추출extracted with ethyl acetate (3×8 ml)
4. 4
   세척The combined organics were washed with brine
5. 5
   건조dried over magnesium sulfate
6. 6
   기타Purification of the
7. 7
   농축concentrate by preparative TLC on silica gel (ethyl acetate:hexane (1:1)+1% methanol)

실험 절차

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).

출처