Reacción #335446

Ecuación de reacción

17-ethyl-1,14-dihydroxy-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

sec-butenyl trichloroacetimidate

Trifluoromethanesulfonic acid

→

title compounds

17-Ethyl-1,14-dihydroxy-12-[2'-(3"-sec-butenyloxy-4"-hydroxycyclohexyl)-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

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONto mix for 5 minutes
2. 2
   OtroAfter 15 minutes the reaction was quenched by the addition of saturated sodium bicarbonate
3. 3
   Extracciónextracted with ethyl acetate (3×8 ml)
4. 4
   LavadoThe combined organics were washed with brine
5. 5
   Secadodried over magnesium sulfate
6. 6
   OtroPurification of the
7. 7
   Concentraciónconcentrate by preparative TLC on silica gel (ethyl acetate: hexane (1:1)+1% methanol)

Procedimiento

To a solution of 17-ethyl-1,14-dihydroxy-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 (150 mg in 3 ml 33% methylene chloride in cyclohexane) sec-butenyl trichloroacetimidate (62 μl neat) was added and the reagents allowed to mix for 5 minutes. Trifluoromethanesulfonic acid (2 μl neat) was added slowly via syringe and the mixture stirred at room temperature. After 15 minutes 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 compounds (11 mg 4"-ether; 13 mg 3"-ether).

Fuente