(6S,8S,9S,10R,11S,13S,14S,16R,17S)-6-fluoro-11-hydroxy-17-(2-hydroxyacetyl)-10,13,16-trimethyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-3-one

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

Procedure: 26 mmol of fluocortolone (FC) is reacted with 32 mmol of Boc-valine (Boc-Val-OH), 2.9 mmol of 4-dimethylaminopyridine and 34 mmol of dicyclohexylcarbodiimide in dichloromethane/dioxane 3:2. Chromatography (ethyl acetate/hexane 2:1): F1 9.3 g of pure product, F2 4.8 g of slightly contaminated product. (Total yield 92%) crystallization of F1 from ethyl acetate/hexane yields 7.0 g (46%) of (2S)-2-((1,1-dimethylethoxycarbonyl)-amino)-3-methyl-butyric acid [11β,21-dihydroxy-6α-fluoro-16α-methyl-3,20-dioxo-pregna-1,4-dien-21-yl] ester. (Total yield 92%) crystallization of F1 from ethyl acetate/hexane

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

Procedure: 26 mmol of fluocortolone (FC) is reacted with 32 mmol of Boc-valine (Boc-Val-OH), 2.9 mmol of 4-dimethylaminopyridine and 34 mmol of dicyclohexylcarbodiimide in dichloromethane/dioxane 3:2. Chromatography (ethyl acetate/hexane 2:1): F1 9.3 g of pure product, F2 4.8 g of slightly contaminated product. (Total yield 92%) crystallization of F1 from ethyl acetate/hexane yields 7.0 g (46%) of (2S)-2-((1,1-dimethylethoxycarbonyl)-amino)-3-methyl-butyric acid [11β,21-dihydroxy-6α-fluoro-16α-methyl-3,20-dioxo-pregna-1,4-dien-21-yl] ester. (Total yield 92%) crystallization of F1 from ethyl acetate/hexane

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

Procedure: 26 mmol of fluocortolone (FC) is reacted with 32 mmol of Boc-valine (Boc-Val-OH), 2.9 mmol of 4-dimethylaminopyridine and 34 mmol of dicyclohexylcarbodiimide in dichloromethane/dioxane 3:2. Chromatography (ethyl acetate/hexane 2:1): F1 9.3 g of pure product, F2 4.8 g of slightly contaminated product. (Total yield 92%) crystallization of F1 from ethyl acetate/hexane yields 7.0 g (46%) of (2S)-2-((1,1-dimethylethoxycarbonyl)-amino)-3-methyl-butyric acid [11β,21-dihydroxy-6α-fluoro-16α-methyl-3,20-dioxo-pregna-1,4-dien-21-yl] ester. (Total yield 92%) crystallization of F1 from ethyl acetate/hexane

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Five grams of 6α-fluoro-11β,21 -dihydroxy-16α-methyl-1,4-pregnadiene-3,20-dione is refluxed in 25 ml. of pyridine with 5 g. of succinic acid anhydride for 2 hours. After cooling to 20°C., the solution is stirred into ice water, acidified with hydrochloric acid, and the thus-precipitated product is vacuumfiltered, washed with water, and dried. By recrystallization from ethyl acetate, 4.85 g. of (6α-fluoro-11β-hydroxy-3,20-dioxo-16α-methyl-1,4-pregnadien-21-yl) hydrogen succinate is obtained, m.p. 212°-214° C. washed with water dried By recrystallization from ethyl acetate, 4.85 g