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

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

Procedure: Dexamethasone (9α-fluoro-11β,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione) can also be prepared from 17β-hydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione by first transforming it to 17α,21-dihydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione 21-acetate as described above and next transforming it to 17α,21-dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate by the process of U.S. Pat. No. 3,130,209. 17α,21-Dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate is then epoxidized by means well known to those skilled in the art, see for example U.S. Pat. No. 3,980,778, Examples 2 and 7 to produce 9β,11β-epoxy-17α,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione which is transformed to dexamethasone 21-acetate by the process of U.S. Pat. No. 3,007,932, Example 2.

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

Procedure: An amount equivalent to 0.030 g of dexamethasone (1, 0.076 mmol, 1.0 equiv.) was completely dissolved in 1 mL of pyridine (non-anhydrous) and 0.038 g of succinic anhydride (0.382 mmol, 5.0 equiv.) was added to the clear solution. Then 1-2 mg of DMAP (7.6 μmol, 0.1 equiv.) was added to the solution and reaction was allowed to run for 48 h at r.t. under N2-flow. After 48 h, pyridine was evaporated under reduced pressure (in a rotary evaporator). A volume equivalent to 10 mL of H2O was added to the evaporated residue. A white precipitate was observed which was stirred for 10 minutes and then centrifuged. The resulting precipitate was washed again with 10 mL of H2O and the washed residue was lyophilized to yield the target product (2). After 48 h pyridine was evaporated under reduced pressure ( in a rotary evaporator) A volume equivalent to 10 mL of H2O was added to the evaporated residue The resulting precipitate was washed again with 10 mL of H2O

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

Procedure: An amount equivalent to 0.030 g of dexamethasone (1, 0.076 mmol, 1.0 equiv.) was completely dissolved in 1 mL of pyridine (non-anhydrous) and 0.038 g of succinic anhydride (0.382 mmol, 5.0 equiv.) was added to the clear solution. Then 1-2 mg of DMAP (7.6 μmol, 0.1 equiv.) was added to the solution and reaction was allowed to run for 48 h at r.t. under N2-flow. After 48 h, pyridine was evaporated under reduced pressure (in a rotary evaporator). A volume equivalent to 10 mL of H2O was added to the evaporated residue. A white precipitate was observed which was stirred for 10 minutes and then centrifuged. The resulting precipitate was washed again with 10 mL of H2O and the washed residue was lyophilized to yield the target product (2). After 48 h pyridine was evaporated under reduced pressure ( in a rotary evaporator) A volume equivalent to 10 mL of H2O was added to the evaporated residue The resulting precipitate was washed again with 10 mL of H2O

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

Procedure: The 21-hydroxy group of dexamethasone is not required for anti-inflammatory activity, and therefore is an ideal choice for conjugation to a polycation (FIG. 1A) (Schimmer et al., 1996, in The Pharmacological Basis of Therapeutics, 1459-1485, eds. Hardman and Limbird, McGraw-Hill, New York). A one-pot reaction between spermine, 2-iminothiolane (Traut's reagent) and dexamethasone mesylate yielded the dexamethasone-spermine and disubstituted conjugates, (DS and D2S, respectively) (FIG. 1B). Traut's reagent is selectively ring-opened by the primary amines (Hermanson, 1996, Bioconjugate Techniques, Academic Press) on spermine, forming a hydrolytically sensitive amidimide bond (Hermanson, 1996, Bioconjugate Techniques, Academic Press) between spermine and iminothiolane and a reactive thiolate anion that reacts with the α-keto mesylate on the 21 position of dexamethasone mesylate (Simmons et al., 1980, J. Org. Chem. 45:084-3088), yielding an α-keto thioether linkage between the dexamethasone and iminothiolane. Dexamethasone mesylate (prepared or received from Steraloids, N.H.) or dexamethasone (Steraloids, N.H.), 2-iminothiolane (Traut's reagent) (Pierce), spermine (Sigma), and ethanol or DMSO (Aldrich) were used as received. A total of 105 mg (223 μmol) of dexamethasone-mesylate, and 28.4 mg (206 μmol) of Trout's reagent were dissolved together in either DMSO or ethanol prior to addition of 31.9 μl (145 μmol of spermine at room temperature. The conjugation reaction was complete in 45 minutes by TLC. HPLC purification (60/40 0.1% TFA/acetonitrile, Hamilton PRP-1 column), evaporative solvent removal, and freeze-drying yielded both DS and D2S as white powders, 1H NMR of DS confirmed the presence of the 3-bis-enone and 11- and 17-hydroxy groups required for glucocorticoid activity (FIG. 1A) as well as 1H signals from the conjugated spermine and the 21-α-keto thioether group. Hydrolysis of DS in 1M NaOH for 20 minutes resulted in the cleavage of the amidimide linkage between spermine and iminothiolane, forming a dexamethasone-amide (DA) (FIG. 1B), which has a 21-substituted butyl thioether amide side-chain on dexamethasone. For DA, FIG. 1B: Calc: C, 63.26; H, 7.35; N, 2.84. Found: C, 63.44; H, 7.27; N, 2.83. Water solubility: DS>100,000 mg/l; DA 60 mg/l; (dexamethasone 100 mg/l).

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

Procedure: The 21-hydroxy group of dexamethasone is not required for anti-inflammatory activity, and therefore is an ideal choice for conjugation to a polycation (FIG. 1A) (Schimmer et al., 1996, in The Pharmacological Basis of Therapeutics, 1459-1485, eds. Hardman and Limbird, McGraw-Hill, New York). A one-pot reaction between spermine, 2-iminothiolane (Traut's reagent) and dexamethasone mesylate yielded the dexamethasone-spermine and disubstituted conjugates, (DS and D2S, respectively) (FIG. 1B). Traut's reagent is selectively ring-opened by the primary amines (Hermanson, 1996, Bioconjugate Techniques, Academic Press) on spermine, forming a hydrolytically sensitive amidimide bond (Hermanson, 1996, Bioconjugate Techniques, Academic Press) between spermine and iminothiolane and a reactive thiolate anion that reacts with the α-keto mesylate on the 21 position of dexamethasone mesylate (Simmons et al., 1980, J. Org. Chem. 45:084-3088), yielding an α-keto thioether linkage between the dexamethasone and iminothiolane. Dexamethasone mesylate (prepared or received from Steraloids, N.H.) or dexamethasone (Steraloids, N.H.), 2-iminothiolane (Traut's reagent) (Pierce), spermine (Sigma), and ethanol or DMSO (Aldrich) were used as received. A total of 105 mg (223 μmol) of dexamethasone-mesylate, and 28.4 mg (206 μmol) of Trout's reagent were dissolved together in either DMSO or ethanol prior to addition of 31.9 μl (145 μmol of spermine at room temperature. The conjugation reaction was complete in 45 minutes by TLC. HPLC purification (60/40 0.1% TFA/acetonitrile, Hamilton PRP-1 column), evaporative solvent removal, and freeze-drying yielded both DS and D2S as white powders, 1H NMR of DS confirmed the presence of the 3-bis-enone and 11- and 17-hydroxy groups required for glucocorticoid activity (FIG. 1A) as well as 1H signals from the conjugated spermine and the 21-α-keto thioether group. Hydrolysis of DS in 1M NaOH for 20 minutes resulted in the cleavage of the amidimide linkage between spermine and iminothiolane, forming a dexamethasone-amide (DA) (FIG. 1B), which has a 21-substituted butyl thioether amide side-chain on dexamethasone. For DA, FIG. 1B: Calc: C, 63.26; H, 7.35; N, 2.84. Found: C, 63.44; H, 7.27; N, 2.83. Water solubility: DS>100,000 mg/l; DA 60 mg/l; (dexamethasone 100 mg/l).

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 200 mL Erlenmeyer flask equipped with a magnetic stir bar and a rubber septum was charged with 5 grams of dexamethasone (12.7 mmol, 1 equivalent) and 16 mL of anhydrous pyridine. The flask was cooled to 0° C. with an ice bath, and 1.2 mL of methanesulfonyl chloride was added. After 1 hour, 0.8 mL of additional methanesulfonyl chloride was added. At two hours, the solution was poured into 100 mL of cold 1M HCl, forming a precipitate. The precipitate was filtered and redissolved in 250 mL of ethanol, and precipitated into 250 mL of 1M HCl. The precipitate was filtered and recrystallized in ethanol, filtered, and dried under vacuum yielding 4.95 g (82.6%) of dexamethasone mesylate. A 200 mL Erlenmeyer flask equipped with a magnetic stir bar At two hours forming a precipitate The precipitate was filtered redissolved in 250 mL of ethanol precipitated into 250 mL of 1M HCl The precipitate was filtered recrystallized in ethanol filtered dried under vacuum

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

Procedure: 5 (0.54 g, 2.4 mmol, 1.05 eqv.) was dissolved in dry THF (5 mL) and DMAP (0.14 g, 1.2 mmol, 0.5 eqv.) was added to the solution under nitrogen. After cooling on ice, a dexamethasone solution (0.91 g, 2.3 mmol, 1 eqv.) in dry THF (25 mL) and DCC (0.525 g, 2.5 mmol, 1.1 eqv.) were added to the mixture. The reaction mixture was slowly warmed to room temperature and stirred overnight at RT. The completion of the reaction was confirmed by TLC (EtOAc/Hex, 20:1 (v/v), Rf: 0.24). Most of the solvent was evaporated and the remaining solution was purified on a 20 cm silica gel column (EtOAc/Hex, 20:1 (v/v)). 1 g (73% yield) DMSL2 was obtained as a yellow fluffy solid. After cooling on ice Most of the solvent was evaporated the remaining solution was purified on a 20 cm silica gel column (EtOAc/Hex, 20:1 (v/v)) was obtained as a yellow fluffy solid

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

Procedure: A solution of 33 g (84.09 mmole) of 9-fluoro-16α-methyl-11β,17,21-trihydroxypregna-1,4-diene-3,20-dione in 50% acetic acid (3 liters) was stirred with 320 g of sodium bismuthate at room temperature for 20 hours. The resulting brown suspension was filtered through a bed of deactivated silica powder and washed with 300 ml of 50% acetic acid. The filtrate was concentrated in vacuo to 500 ml, diluted with 250 ml of 20% hydrochloric acid and extracted with chloroform. The chloroform solution was washed with 20% hydrochloric acid and water, dried over anhydrous Na2SO4 and evaporated in vacuo to give a solid. This was dissolved in chloroform and chromatographed on a 250 g-silica gel column, eluting successively with chloroform and 1:4 ethyl acetate-chloroform to give 22.8 g (81.6%) of tlc-homogeneous title compound, melting point 240°-242° with consistent spectral data. The resulting brown suspension was filtered through a bed of deactivated silica powder washed with 300 ml of 50% acetic acid The filtrate was concentrated in vacuo to 500 ml diluted with 250 ml of 20% hydrochloric acid extracted with chloroform The chloroform solution was washed with 20% hydrochloric acid and water dried over anhydrous Na2SO4 evaporated in vacuo to give a solid chromatographed on a 250 g-silica gel column eluting successively with chloroform and 1:4 ethyl acetate-chloroform

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

Procedure: Dexamethasone (9α-fluoro-11β,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione) can also be prepared from 17β-hydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione by first transforming it to 17α,21-dihydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione 21-acetate as described above and next transforming it to 17α,21-dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate by the process of U.S. Pat. No. 3,130,209. 17α,21-Dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate is then epoxidized by means well known to those skilled in the art, see for example U.S. Pat. No. 3,980,778, Examples 2 and 7 to produce 9β,11β-epoxy-17α,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione which is transformed to dexamethasone 21-acetate by the process of U.S. Pat. No. 3,007,932, Example 2.

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

Procedure: Dexamethasone (9α-fluoro-11β,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione) can also be prepared from 17β-hydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione by first transforming it to 17α,21-dihydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione 21-acetate as described above and next transforming it to 17α,21-dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate by the process of U.S. Pat. No. 3,130,209. 17α,21-Dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate is then epoxidized by means well known to those skilled in the art, see for example U.S. Pat. No. 3,980,778, Examples 2 and 7 to produce 9β,11β-epoxy-17α,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione which is transformed to dexamethasone 21-acetate by the process of U.S. Pat. No. 3,007,932, Example 2.

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

Procedure: Dexamethasone (9α-fluoro-11β,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione) can also be prepared from 17β-hydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione (VI) by first transforming it to 17α,21-dihydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione 21-acetate as described above and next transforming it to 17α,21-dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate by the process of U.S. Pat. No. 3,130,209. 17α,21-Dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate is then epoxidized by means well known to those skilled in the art, see for example U.S. Pat. No. 3,980,778, Examples 2 and 7 to produce 9β,11β-epoxy-17α,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione which is transformed to dexamethasone 21-acetate by the process of U.S. Pat. No. 3,007,932, Example 2.

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

Procedure: Dexamethasone (9α-fluoro-11β,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione) can also be prepared from 17β-hydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione (VI) by first transforming it to 17α,21-dihydroxy-16-methylenepregna-1,4,9(11)-triene-3,20-dione 21-acetate as described above and next transforming it to 17α,21-dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate by the process of U.S. Pat. No. 3,130,209. 17α,21-Dihydroxy-16α-methylpregna-1,4,9(11)-triene-3,20-dione 21-acetate is then epoxidized by means well known to those skilled in the art, see for example U.S. Pat. No. 3,980,778, Examples 2 and 7 to produce 9β,11β-epoxy-17α,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione which is transformed to dexamethasone 21-acetate by the process of U.S. Pat. No. 3,007,932, Example 2.