2-Nitrobenzenesulfonyl chloride → HCID 57124729, compound

Participants

Reaction Steps

To a solution of 17-allyl-1-hydroxy-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 (176 mg, Example 57) in dry methylene chloride (10 ml) is added diisopropylethylamine (117 μl) followed by 2-nitrobenzenesulfonyl chloride (104 mg), then 4-dimethylaminopyridine (55 mg). The yellow solution is stirred at room temperature under nitrogen atmosphere for 5 h, then quenched with sat'd. aqueous sodium bicarbonate solution. The organic layer is washed (water, sat'd. NaHCO3, sat'd. NaCl), dried (anhydrous Na2SO4) and the solvent is removed in vacuo. Chromatography on silica gel gave 17-allyl-1-hydroxy-12-[2'-[4"-(2"'-nitrobenzenesulfonyloxy)-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 as an off-white solid (120 mg). This off-white solid (100 mg) was dissolved in dry DMF (1 ml) and to this solution was added sodium azide (33 mg) in one portion and heated at 80° C. under nitrogen atmosphere for 5.5 h. The reaction mixture was cooled, poured into water (5 ml) and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate and purified by column chromatography on silica gel (1:1 ethyl acetate/hexane) to give 17-allyl-1-hydroxy-12-[2'-(4"-azido-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 (66 mg). This material (60 mg) and triphenylphosphine (19 mg) in wet benzene (2 ml) was refluxed for 6.5 h. The solvent was removed in vacuo and the residue was purified on silica gel (eluted first with 5% MeOH/CH2Cl2, then 1% NH4OH in 5% MeOH/CH2Cl2) to give 36 mg of the title compound.

Provenance & Evidence