37413-91-5

Basic information

• Product Name: 3,20-Dioxopregna-1,4,9(11),16-tetraen-21-yl acetate
• Synonyms: Pregna-1,4,9(11),16-tetraen-21-ol-3,20-dione 21-acetate;21-Acetoxypregna-1,4,9(11),16-tetrene-3,20-dione;3,20-Dioxopregna-1,4,9(11),16-tetrene-21-ol acetate;21-(Acetyloxy)-pregna-1,4,9(11),16-tetraene-3,20-dione;2-((8S,10S,13S,14S)-10,13-DiMethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate;21-Acetoxypregna-1,4,9(11),16-tetraene-3,20-dione;Pregna-1,4,9(11),16-tetraene-3,20-dione,21-(acetyloxy)-;Acetate tetraene Matter
• CAS NO: 37413-91-5
• Molecular Formula: C₂₃H₂₆O₄
• Molecular Weight: 366.45
• EINECS: 253-497-3
• Product Categories: Intermediates & Fine Chemicals;Pharmaceuticals;Steroids
• Mol File: 37413-91-5.mol
• Article Data: 8

Chemical Properties

• Melting Point: 173-175°C
• Boiling Point: 534.568 °C at 760 mmHg
• Flash Point: 233.008 °C
• Appearance: /
• Density: 1.211 g/cm³
• Vapor Pressure: 0mmHg at 25°C
• Refractive Index: 1.585
• Storage Temp.: Refrigerator
• CAS DataBase Reference: 3,20-Dioxopregna-1,4,9(11),16-tetraen-21-yl acetate(CAS DataBase Reference)
• NIST Chemistry Reference: 3,20-Dioxopregna-1,4,9(11),16-tetraen-21-yl acetate(37413-91-5)
• EPA Substance Registry System: 3,20-Dioxopregna-1,4,9(11),16-tetraen-21-yl acetate(37413-91-5)

Safety Data

• Hazardous Substances Data: 37413-91-5(Hazardous Substances Data)

Usage

Chemical Properties

White Solid

InChI:InChI=1/C23H26O4/c1-14(24)27-13-21(26)20-7-6-18-17-5-4-15-12-16(25)8-10-22(15,2)19(17)9-11-23(18,20)3/h7-10,12,17-18H,4-6,11,13H2,1-3H3/t17-,18-,22-,23-/m0/s1

Synthetic route

pregna-1,4,9(11)-triene-17α,21-diol-3,20-dione 21-acetate (4380-55-6) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Stage #1: pregna-1,4,9(11)-triene-17α,21-diol-3,20-dione 21-acetate With pyridine; N-chloro-succinimide at -15℃; for 1h; Inert atmosphere; Stage #2: With sulfur dioxide at -10℃; for 0.5h; Inert atmosphere;	98.8%

prednisolone 21-acetate (52-21-1) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Stage #1: prednisolone 21-acetate With pyridine; N-chloro-succinimide at -15 - 20℃; for 0.416667h; Inert atmosphere; Stage #2: With sulfur dioxide for 1h; Inert atmosphere;	83.5%

prednisolone 21-acetate (52-21-1) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + pregna-1,4,9(11)-triene-17α,21-diol-3,20-dione 21-acetate (4380-55-6) + 2-((10S)-10,17-dimethyl-3-oxo-6,7,8,10,12,15,16,17-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate + C46H54O11S

Conditions	Yield
With pyridine; thionyl chloride In N,N-dimethyl-formamide at 20℃; Reagent/catalyst; Temperature;	A 50% B n/a C n/a D n/a

21-acetoxy-pregna-4,9(11),16-triene-3,20-dinone (23460-76-6) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
With selenium(IV) oxide; tert-butyl alcohol
With pyridine; selenium(IV) oxide In tert-butyl alcohol for 24h; Reflux; Inert atmosphere;	25.27 g

2,4,6-trimethyl-pyridine (108-75-8) + 21-acetoxy-2α-bromo-pregna-4,9(11),16-triene-3,20-dione → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

prednisolon (50-24-8) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: thionyl chloride / tetrahydrofuran / 0.67 h / 0 °C / Inert atmosphere 1.2: 1.25 h / 5 - 20 °C 2.1: dmap / dichloromethane / 0.5 h / 20 °C / Inert atmosphere 3.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / tetrahydrofuran / 3 h / 60 °C / Inert atmosphere View Scheme

C21H24O3 → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: dmap / dichloromethane / 0.5 h / 20 °C / Inert atmosphere 2: 1,8-diazabicyclo[5.4.0]undec-7-ene / tetrahydrofuran / 3 h / 60 °C / Inert atmosphere View Scheme

18-hydroxypregnane-1,4,9(11),17-tetraene-3,19-dione-18-acetate → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene In tetrahydrofuran at 60℃; for 3h; Inert atmosphere;	1.92 g
With 1,8-diazabicyclo[5.4.0]undec-7-ene at 50℃; for 5h; Inert atmosphere;	27.6 g

C23H27BrO4 → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
With potassium acetate; acetic acid In N,N-dimethyl-formamide at 105℃; for 5h; Reagent/catalyst; Solvent; Temperature; Inert atmosphere; Large scale;	965 g

androsta-1,4,9(11)-triene-3,17-dione (15375-21-0) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions

Yield

Multi-step reaction with 4 steps 1.1: potassium hydroxide / tetrahydrofuran; acetone / 2 h / 0 - 40 °C / Inert atmosphere; Large scale 1.2: 15 h / -5 - 5 °C / Large scale 2.1: dmap; triethylamine / dichloromethane / 7 h / Inert atmosphere; Reflux; Large scale 3.1: N-Bromosuccinimide / acetone; tert-butyl alcohol / 2 h / 10 - 20 °C / Large scale 3.2: 1 h / 30 - 35 °C / Inert atmosphere; Large scale 4.1: potassium acetate; acetic acid / N,N-dimethyl-formamide / 5 h / 105 °C / Inert atmosphere; Large scale View Scheme

17α-ethynyl-17β-hydroxy-1,4,9(11)-trieneandrostan-3-one → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: dmap; triethylamine / dichloromethane / 7 h / Inert atmosphere; Reflux; Large scale 2.1: N-Bromosuccinimide / acetone; tert-butyl alcohol / 2 h / 10 - 20 °C / Large scale 2.2: 1 h / 30 - 35 °C / Inert atmosphere; Large scale 3.1: potassium acetate; acetic acid / N,N-dimethyl-formamide / 5 h / 105 °C / Inert atmosphere; Large scale View Scheme

androst-4,9(11)-dien-3,17-dione (1035-69-4) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions

Yield

Multi-step reaction with 6 steps 1.1: acetone / 0.5 h / 20 °C 2.1: calcium oxide; calcium chloride; iodine / methanol; dichloromethane; water / 1.5 h / 20 °C / Inert atmosphere 3.1: potassium acetate / N,N-dimethyl-formamide / 2 h / 65 °C / Inert atmosphere 3.2: 0.5 h / Inert atmosphere 4.1: toluene-4-sulfonic acid; trifluoroacetic anhydride / dichloromethane / 2.5 h / 20 °C 4.2: 0.25 h 5.1: potassium acetate / dimethyl sulfoxide / 2 h / 80 °C / Inert atmosphere 5.2: 0.5 h / Inert atmosphere 6.1: pyridine; selenium(IV) oxide / tert-butyl alcohol / 24 h / Reflux; Inert atmosphere View Scheme

9-alpha-hydroxyandrost-4-ene-3,17-dione (560-62-3, 23015-99-8) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions

Yield

Multi-step reaction with 6 steps 1.1: diethyl ether / 0.5 h / 20 °C 2.1: calcium oxide; calcium chloride; iodine / methanol; dichloromethane; water / 1.5 h / 20 °C / Inert atmosphere 3.1: potassium acetate / N,N-dimethyl-formamide / 2 h / 65 °C / Inert atmosphere 3.2: 0.5 h / Inert atmosphere 4.1: toluene-4-sulfonic acid; trifluoroacetic anhydride / dichloromethane / 2.5 h / 20 °C 4.2: 0.25 h 5.1: potassium acetate / dimethyl sulfoxide / 2 h / 80 °C / Inert atmosphere 5.2: 0.5 h / Inert atmosphere 6.1: pyridine; selenium(IV) oxide / tert-butyl alcohol / 24 h / Reflux; Inert atmosphere View Scheme

17α-Hydroxy-21-iodopregna-4,9(11)-diene-3,20-dione (95816-38-9) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions

Yield

Multi-step reaction with 4 steps 1.1: potassium acetate / N,N-dimethyl-formamide / 2 h / 65 °C / Inert atmosphere 1.2: 0.5 h / Inert atmosphere 2.1: toluene-4-sulfonic acid; trifluoroacetic anhydride / dichloromethane / 2.5 h / 20 °C 2.2: 0.25 h 3.1: potassium acetate / dimethyl sulfoxide / 2 h / 80 °C / Inert atmosphere 3.2: 0.5 h / Inert atmosphere 4.1: pyridine; selenium(IV) oxide / tert-butyl alcohol / 24 h / Reflux; Inert atmosphere View Scheme

pregna-4,9(11)-diene-3,20-dione-17-hydroxy-21-methyl (34184-82-2) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions

Yield

Multi-step reaction with 5 steps 1.1: calcium oxide; calcium chloride; iodine / methanol; dichloromethane; water / 1.5 h / 20 °C / Inert atmosphere 2.1: potassium acetate / N,N-dimethyl-formamide / 2 h / 65 °C / Inert atmosphere 2.2: 0.5 h / Inert atmosphere 3.1: toluene-4-sulfonic acid; trifluoroacetic anhydride / dichloromethane / 2.5 h / 20 °C 3.2: 0.25 h 4.1: potassium acetate / dimethyl sulfoxide / 2 h / 80 °C / Inert atmosphere 4.2: 0.5 h / Inert atmosphere 5.1: pyridine; selenium(IV) oxide / tert-butyl alcohol / 24 h / Reflux; Inert atmosphere View Scheme

anecortave (7753-60-8) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: toluene-4-sulfonic acid; trifluoroacetic anhydride / dichloromethane / 2.5 h / 20 °C 1.2: 0.25 h 2.1: potassium acetate / dimethyl sulfoxide / 2 h / 80 °C / Inert atmosphere 2.2: 0.5 h / Inert atmosphere 3.1: pyridine; selenium(IV) oxide / tert-butyl alcohol / 24 h / Reflux; Inert atmosphere View Scheme

pregna-4,9(11)-diene-17α,21-diol-3,20-dione 17,21-diacetate (7780-63-4) → 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: potassium acetate / dimethyl sulfoxide / 2 h / 80 °C / Inert atmosphere 1.2: 0.5 h / Inert atmosphere 2.1: pyridine; selenium(IV) oxide / tert-butyl alcohol / 24 h / Reflux; Inert atmosphere View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → C24H27BrO6

Conditions	Yield
Stage #1: 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate; N,N-dimethyl-formamide With perchloric acid In water at 20 - 27℃; Inert atmosphere; Stage #2: With 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione In water; N,N-dimethyl-formamide at 20 - 35℃; Inert atmosphere;	99%

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 16α,17α,21-trihydroxypregna-1,4,9(11)-triene-3,20-dione-21-acetate (77017-20-0)

Conditions	Yield
Stage #1: 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate With formic acid In acetone at -5 - 0℃; for 0.0833333h; Stage #2: With potassium permanganate In water; acetone at -5 - 0℃; for 0.166667h;	96%
With potassium permanganate
With potassium permanganate; formic acid In water; acetone at -7 - -3℃; for 0.5h; Industrial scale;	15 kg
With potassium permanganate; oxalic acid In water; butanone at -5℃; Reagent/catalyst; Solvent; Temperature;	50.5 g

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → C23H26O5

Conditions	Yield
Stage #1: 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate With perchloric acid; 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione In water; acetone at -10 - -5℃; for 2h; Stage #2: With potassium carbonate In water; acetone at -5 - 35℃; for 12h;	96%
Stage #1: 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate With perchloric acid; 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione In acetone at -10 - -5℃; Stage #2: With potassium carbonate In acetone at 33 - 37℃;	83.36%

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → C23H28O6

Conditions	Yield
With potassium permanganate; formic acid In water; acetone at -5 - 0℃; for 0.5h; Solvent; Temperature; Inert atmosphere;	86%

(phenylthio)nitromethane (60595-16-6) + 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → Acetic acid 2-[(8S,10S,13S,14S,16R,17S)-10,13-dimethyl-16-(nitro-phenylsulfanyl-methyl)-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl]-2-oxo-ethyl ester (144602-46-0)

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene In tetrahydrofuran; tert-butyl alcohol Yield given;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + methyl-d3-magnesium iodide (41251-37-0) → C24H27(2)H3O4

Conditions	Yield
With methylmagnesium chloride; copper(II) propionate In tetrahydrofuran at -9 - -7℃; for 0.666667h;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + <14C>methyl iodide (22092-83-7) → C23(14)CH30O4

Conditions	Yield
With methylmagnesium chloride; copper(II) propionate In tetrahydrofuran at -9 - -7℃; for 0.666667h;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 17α,21-dihydroxy-16β-methyl-1,4,9(11)-pregnatriene-3,20-dione 21-acetate (910-99-6)

Conditions	Yield
Multi-step reaction with 5 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc 3: m-chloroperbenzoic acid 5: 90 percent / Wilkinson catalyst View Scheme
Multi-step reaction with 5 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc 3: 57 percent / m-chloroperbenzoic acid 5: 90 percent / Wilkinson catalyst View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → Acetic acid 2-((8S,10S,13S,14S,17R)-17-hydroxy-10,13-dimethyl-16-methylene-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxo-ethyl ester (19683-24-0)

Conditions	Yield
Multi-step reaction with 4 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc 3: m-chloroperbenzoic acid View Scheme
Multi-step reaction with 4 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc 3: 57 percent / m-chloroperbenzoic acid View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → Acetic acid 2-[(8S,10S,13S,14S,16R,17S)-16-(bis-phenylsulfanyl-methyl)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl]-2-oxo-ethyl ester (144602-47-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → Acetic acid 2-[(8S,10S,13S,14S,16R,17S)-16-(benzenesulfinyl-phenylsulfanyl-methyl)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl]-2-oxo-ethyl ester (144602-48-2)

Conditions	Yield
Multi-step reaction with 3 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc 3: m-chloroperbenzoic acid View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → Acetic acid 2-[(8S,10S,13S,14S,16R,17S)-16-(bis-benzenesulfinyl-methyl)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl]-2-oxo-ethyl ester (144602-43-7)

Conditions	Yield
Multi-step reaction with 3 steps 1: DBU / 2-methyl-propan-2-ol; tetrahydrofuran 2: 70 percent / HOAc 3: 57 percent / m-chloroperbenzoic acid View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 16α,21-diacetoxy-17-hydroxy-pregna-1,4,9(11)-triene-3,20-dione (95943-95-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: KMnO4 View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 9β,11β-epoxy-21-hydroxypregna-1,4,16-triene-3,20-dione 21-acetate (103466-44-0)

Isopropenyl acetate (108-22-5) + 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 3,21-diacetyloxy-pregna-1,3,5,9(11),16-pentaene-20-one (1058744-83-4)

Conditions	Yield
toluene-4-sulfonic acid In water at 80℃; for 4h;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 6α-fluoro-1,4,9,16-tetraenepregna-3,20-dione-21-acetate (2476-74-6)

Conditions	Yield
With Selectfluor In acetonitrile at -10 - 25℃; for 5h;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + methylmagnesium chloride (676-58-4) + methyl iodide (74-88-4) → 2-oxo-2-((8S,10S,13S,14S,16R,17S)-10,13,16,17-tetramethyl-3-oxo-2,3,6,7,8,10,12,13,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl)ethyl acetate (1201591-22-1)

Conditions	Yield
Stage #1: 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate; methylmagnesium chloride; copper(II) propionate In tetrahydrofuran Cooling with acetone-dry ice; Stage #2: methyl iodide In tetrahydrofuran

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + methylmagnesium chloride (676-58-4) + 1-(Trimethylsilyl)imidazole (18156-74-6) → (Z)-2-((8S,10S,13S,14S,16R)-10,13,16-trimethyl-3-oxo-7,8,12,13,15,16-hexahydro-3H-cyclopenta[a]phenanthren-17(6H,10H,14H)-ylidene)-2-(trimethylsilyloxy)ethyl acetate (1201591-18-5)

Conditions	Yield
1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; copper(II) propionate In tetrahydrofuran; dichloromethane at -50 - -30℃; Inert atmosphere;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 17α,21-dihydroxy-16α-methyl-1,4,9(11)-pregnatriene-3,20-dione 21-acetate (10106-41-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; copper(II) propionate / dichloromethane; tetrahydrofuran / -50 - -30 °C / Inert atmosphere 2: 3-chloro-benzenecarboperoxoic acid / dichloromethane / 0 °C View Scheme
Multi-step reaction with 2 steps 1.1: dichloromethane; tetrahydrofuran / 3 h / 20 °C / Inert atmosphere 1.2: 3 h / 20 °C / Inert atmosphere 1.3: -50 °C / Inert atmosphere 2.1: acetic acid; peracetic acid / toluene / 0.5 h / -10 °C / Inert atmosphere View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → (8S,10S,13S,14S,16R,17S)-17-(2-hydroxyacetyl)-10,13,16-trimethyl-6,7,8,10,12,13,14,15,16,17-decahydro-1H-cyclopenta[a]phenanthren-3(2H)-one (111669-38-6)

Conditions

Yield

Multi-step reaction with 4 steps 1: 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; copper(II) propionate / dichloromethane; tetrahydrofuran / -50 - -30 °C / Inert atmosphere 2: hydrogenchloride; water / ethyl acetate 3: triethylsilane / Wilkinson's catalyst / dichloromethane / 40 °C 4: potassium carbonate; water / dichloromethane; methanol / 2 h / 5 °C / Inert atmosphere; Cooling with ice View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 16α-methyl-21-hydroxypregna-1,4,9(11)-triene-3,20-dione (56016-90-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; copper(II) propionate / dichloromethane; tetrahydrofuran / -50 - -30 °C / Inert atmosphere 2: hydrogenchloride; water / ethyl acetate 3: potassium carbonate; water / dichloromethane; methanol / 2 h / 5 °C / Inert atmosphere; Cooling with ice View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 2-oxo-2-((8S,10S,13S,14S,16R,17S)-10,13,16-trimethyl-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl)ethyl acetate (4258-83-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; copper(II) propionate / dichloromethane; tetrahydrofuran / -50 - -30 °C / Inert atmosphere 2: hydrogenchloride; water / ethyl acetate View Scheme

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 2-oxo-2-((8S,10S,13S,14S,16R,17S)-10,13,16-trimethyl-3-oxo-2,3,6,7,8,10,12,13,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl)ethyl acetate (177180-83-5)

Conditions	Yield
Multi-step reaction with 3 steps 1: 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; copper(II) propionate / dichloromethane; tetrahydrofuran / -50 - -30 °C / Inert atmosphere 2: hydrogenchloride; water / ethyl acetate 3: triethylsilane / Wilkinson's catalyst / dichloromethane / 40 °C View Scheme

chloro-trimethyl-silane (75-77-4) + 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) + methylmagnesium chloride (676-58-4) → C27H38O4Si

Conditions

Yield

Stage #1: methylmagnesium chloride With copper dichloride In tetrahydrofuran at 3℃; for 0.0166667h; Inert atmosphere; Stage #2: 2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate In tetrahydrofuran at 3℃; for 0.0333333h; Grignard Reaction; Inert atmosphere; Stage #3: chloro-trimethyl-silane; methylmagnesium chloride In tetrahydrofuran at 2℃; for 0.2h; Inert atmosphere;

2-((10S,13S,14S)-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15-octahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate (37413-91-5) → 17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate (2884-51-7)

Conditions

Yield

Multi-step reaction with 4 steps 1.1: perchloric acid / water / 20 - 27 °C / Inert atmosphere 1.2: 20 - 35 °C / Inert atmosphere 2.1: potassium carbonate / water; acetone / 40 - 46 °C / Inert atmosphere 3.1: copper dichloride / tetrahydrofuran / 0.02 h / 3 °C / Inert atmosphere 3.2: 0.03 h / 3 °C / Inert atmosphere 3.3: 1.75 h / 2.5 °C / Inert atmosphere 4.1: peracetic acid; acetic acid / dichloromethane / 18 h / 4 - 20 °C / Inert atmosphere View Scheme

Upstream product

• 7780-63-4 pregna-4,9(11)-diene-17α,21-diol-3,20-dione 17,21-diacetate 
• 7753-60-8 anecortave 
• 34184-82-2 pregna-4,9⁽¹¹⁾-diene-3,20-dione-17-hydroxy-21-methyl 
• 95816-38-9 17α-Hydroxy-21-iodopregna-4,9(11)-diene-3,20-dione 
• 560-62-3 9-alpha-hydroxyandrost-4-ene-3,17-dione 
• 1035-69-4 androst-4,9⁽¹¹⁾-dien-3,17-dione 
• 52-21-1 prednisolone 21-acetate 
• 15375-21-0 androsta-1,4,9⁽¹¹⁾-triene-3,17-dione 
• 4380-55-6 pregna-1,4,9(11)-triene-17α,21-diol-3,20-dione 21-acetate 
• 50-24-8 prednisolon 
• 108-75-8 2,4,6-trimethyl-pyridine 
• 23460-76-6 21-acetoxy-pregna-4,9⁽¹¹⁾,16-triene-3,20-dinone 
• 23460-76-6 21-Acetoxypregna-4,9⁽¹¹⁾,16-trien-3,20-dion 
• 1035-69-4 Androstadien-(4,9,⁽¹¹⁾)-dion-3,17 

Downstream Products

• 77017-20-0 16α,17α,21-trihydroxypregna-1,4,9(11)-triene-3,20-dione-21-acetate 
• 4258-83-7 2-oxo-2-((8S,10S,13S,14S,16R,17S)-10,13,16-trimethyl-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl)ethyl acetate 
• 10106-41-9 17α,21-dihydroxy-16α-methyl-1,4,9(11)-pregnatriene-3,20-dione 21-acetate 
• 911437-91-7 triamcinolone acetonide 
• 13209-41-1 (8S,10S,13S,14S,16R,17R)-17-hydroxy-17-(2-hydroxyacetyl)-10,13,16-trimethyl-7,8,12,14,15,16-hexahydro-6H-cyclopenta[a]phenanthren-3-one 
• 51372-29-3 budesonide 
• 13951-70-7 desonide 
• 86401-80-1 11β,16α,17α,21-tetrahydroxypregnane-1,4-diene-3,20-dione-21-acetate 
• 60864-48-4 C₂₃H₂₇FO₇ 
• 67-73-2 fluocinolone Acetonide 
• 356-12-7 fluocinonide 
• 1058744-83-4 3,21-diacetyloxy-pregna-1,3,5,9(11),16-pentaene-20-one 
• 2476-74-6 6α-fluoro-1,4,9,16-tetraenepregna-3,20-dione-21-acetate 
• 215095-77-5 C₂₁H₂₆O₆ 

Relevant articles and documents

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