17-Ethyl-1,14-dihydroxy-12-[1-(4-hydroxy-3-methoxycyclohexyl)prop-1-en-2-yl]-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-tetrone → 17-Ethyl-1,14-dihydroxy-12-[2'-(4"-allyloxy-3"-methoxycyclohexyl)-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

Beteiligte Stoffe

Reaktionsschritte

To a solution of 17-ethyl-1,14-dihydroxy-12-[2'-(4"-hydroxy-3"-methoxycyclohexyl)-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 (200 mg in 3.0 ml 33% methylene chloride in cyclohexane), allyl trichloroacetimidate (88 μl neat) was added and the reagents allowed to mix for 5 minutes. Trifluoromethanesulfonic acid (4.5 μl neat) was added slowly via syringe and the mixture stirred at room temperature. After 18 hours the reaction was quenched by the addition of saturated sodium bicarbonate and extracted with ethyl acetate (3×5 ml). The combined organics were washed with brine and dried over magnesium sulfate. Purification of the concentrate by flash chromatography on silica gel (ethyl acetate:hexane (1:2)+1% methanol) gave the title compound (156 mg).

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