3-(bromomethyl)-2,2-dimethyloxirane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixed solution of 1α,3β-bis(tert-butyldimethyl-silyloxy)-20(R)-hydroxypregna-5,7,16-triene (51 mg, 0.0911 mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (75 mg, 0.455 mmol) in tetrahydrofuran (2ml) was heated under reflux for 1.5 hours and combined with 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (0.9 ml, 0.900 mmol), and the mixed solution was heated under reflux for 20 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate=10:1, developed twice) to give the title compound as a colorless oil (48.6 mg, 83%). under reflux for 1.5 hours the mixed solution was heated under reflux for 20 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixed solution of 1α,3β-bis(tert-butyldimethyl-silyloxy)-20(R)-hydroxypregna-5,7,16-triene (51 mg, 0.0911 mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (75 mg, 0.455 mmol) in tetrahydrofuran (2ml) was heated under reflux for 1.5 hours and combined with 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (0.9 ml, 0.900 mmol), and the mixed solution was heated under reflux for 20 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate=10:1, developed twice) to give the title compound as a colorless oil (48.6 mg, 83%). under reflux for 1.5 hours the mixed solution was heated under reflux for 20 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: After a mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-triene (97 mg, 0.175mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (145 mg, 0.877 mmol) in tetrahydrofuran (2ml) was heated under reflux for 12 hours, 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (1.8 ml, 1.80 mmol) was added and the mixed solution was heated under reflux for 45 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1) to give the title compound as a colorless oil (113 mg, 100%). under reflux for 12 hours the mixed solution was heated under reflux for 45 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: After a mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-triene (97 mg, 0.175mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (145 mg, 0.877 mmol) in tetrahydrofuran (2ml) was heated under reflux for 12 hours, 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (1.8 ml, 1.80 mmol) was added and the mixed solution was heated under reflux for 45 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1) to give the title compound as a colorless oil (113 mg, 100%). under reflux for 12 hours the mixed solution was heated under reflux for 45 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-triene (67.7 mg, 0.118 mmol), sodium hydride (60% in oil, 40.0 mg, 1.00 mmol) and 1-bromo-2,3-epoxy-3-methylbutane (100 mg, 0.606 mmol) in tetrahydrofuran (1 ml) was refluxed under heating for 1.5 hours. To the thus obtained reaction solution, was added 1.0M L-SELECTRIDE/tetrahydrofuran solution (1.2 ml, 1.2 mmol) at room temperature, followed by stirring at the same temperature for 12 hours. After cooling the reaction solution with ice, a 3N aqueous sodium hydroxide solution and then hydrogen peroxide solution were added to the reaction solution. Immediately after the addition, the mixture was diluted with ethyl acetate and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and evaporated to remove the solvent under reduced pressure; the thus obtained residue was purified by preparative thin layer chromatography (2 sheets (each 0.5 mm thickness), hexane:ethyl acetate=15:1, developed once) to give the titled compound (72.5 mg, 93%) as a colorless oil. under heating for 1.5 hours To the thus obtained reaction solution After cooling the reaction solution with ice Immediately after the addition washed with water and saturated brine The organic layer was dried over anhydrous magnesium sulfate evaporated to remove the solvent under reduced pressure the thus obtained residue was purified by preparative thin layer chromatography (2 sheets (each 0.5 mm thickness), hexane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(R)-hydroxypregna-5,7,16-triene (51 mg, 0.0911 mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (75 mg, 0.455 mmol) in tetrahydrofuran (2 ml) was heated under reflux for 1.5 hours and combined with 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (0.9 ml, 0.900 mmol), and the mixed solution was heated under reflux for 20 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate 10:1, developed twice) to give the title compound as a colorless oil (48.6 mg, 83%). under reflux for 1.5 hours the mixed solution was heated under reflux for 20 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate 10:1

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(R)-hydroxypregna-5,7,16-triene (51 mg, 0.0911 mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (75 mg, 0.455 mmol) in tetrahydrofuran (2 ml) was heated under reflux for 1.5 hours and combined with 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (0.9 ml, 0.900 mmol), and the mixed solution was heated under reflux for 20 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate 10:1, developed twice) to give the title compound as a colorless oil (48.6 mg, 83%). under reflux for 1.5 hours the mixed solution was heated under reflux for 20 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate 10:1

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: After a mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-triene (97 mg, 0.175 mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (145 mg, 0.877 mmol) in tetrahydrofuran (2 ml) was heated under reflux for 12 hours, 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (1.8 ml, 1.80 mmol) was added and the mixed solution was heated under reflux for 45 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1) to give the title compound as a colorless oil (113 mg, 100%). under reflux for 12 hours the mixed solution was heated under reflux for 45 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(R)-hydroxypregna-5,7,16-triene (51 mg, 0.0911 mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (75 mg, 0.455 mmol) in tetrahydrofuran (2 ml) was heated under reflux for 1.5 hours and combined with 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (0.9 ml, 0.900 mmol), and the mixed solution was heated under reflux for 20 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane:ethyl acetate=10:1, developed twice) to give the title compound as a colorless oil (48.6 mg, 83%). under reflux for 1.5 hours the mixed solution was heated under reflux for 20 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by preparative thin layer chromatography (0.5 mm×1, hexane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: After a mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-triene (97 mg, 0.175mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (145 mg, 0.877 mmol) in tetrahydrofuran (2 ml) was heated under reflux for 12 hours, 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (1.8 ml, 1.80 mmol) was added and the mixed solution was heated under reflux for 45 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1) to give the title compound as a colorless oil (113 mg, 100%). under reflux for 12 hours the mixed solution was heated under reflux for 45 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: After a mixed solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-hydroxypregna-5,7,16-triene (97 mg, 0.175mmol), sodium hydride (50 mg, 2.08 mmol) and 4-bromo-2,3-epoxy-2-methylbutane (145 mg, 0.877 mmol) in tetrahydrofuran (2 ml) was heated under reflux for 12 hours, 1M lithium tri-s-butylborohydride solution in tetrahydrofuran (1.8 ml, 1.80 mmol) was added and the mixed solution was heated under reflux for 45 minutes. The reaction solution was stirred with 3N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide at room temperature for 30 minutes, then diluted with ethyl acetate, washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1) to give the title compound as a colorless oil (113 mg, 100%). under reflux for 12 hours the mixed solution was heated under reflux for 45 minutes washed with brine dried over magnesium sulfate The solvent was distilled off under reduced pressure the resulting residue was purified by column chromatography (hexane:ethyl acetate=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 1α,3β-bis(tert-butyldimethylsilyloxy)-17-(hydroxymethyl)androsta-5,7,16-triene (51.6 mg, 0.0947 mmol), sodium hydride (95%, 21.1 mg, 0.879 mmol) and 1-bromo-2,3-epoxy-3-methylbutane (91.2 mg, 0.553 mmol) in tetrahydrofuran (1 ml) was stirred at room temperature for 20 min. and refluxed under heating for 20 min. The reaction solution was diluted with ethyl acetate and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, evaporated under reduced pressure to remove the solvent, and the thus obtained residue was purified by preparative thin layer chromatography (1 sheet (0.5 mm thickness), hexane:ethyl acetate=10:1, developed twice) to give the titled compound (48.3 mg, 81%) as a pale yellow oil. refluxed under heating for 20 min washed with water and saturated brine The organic layer was dried over anhydrous magnesium sulfate evaporated under reduced pressure to remove the solvent the thus obtained residue was purified by preparative thin layer chromatography (1 sheet (0.5 mm thickness), hexane