2755-10-4

Basic information

• Product Name: 9beta,10alpha-pregn-4-ene-3,20-dione
• Synonyms: 9beta,10alpha-pregn-4-ene-3,20-dione;(9β,10α)-Pregn-4-ene-3,20-dione;(9β,10α)-Progesterone;Lumiprogesterone
• CAS NO: 2755-10-4
• Molecular Formula: C21H30O2
• Molecular Weight: 314.4617
• EINECS: 220-407-9
• Mol File: 2755-10-4.mol
• Article Data: 7

Chemical Properties

• Melting Point: 154-156 °C
• Boiling Point: 447.2°Cat760mmHg
• Flash Point: 166.7°C
• Appearance: /
• Density: 1.08g/cm³
• CAS DataBase Reference: 9beta,10alpha-pregn-4-ene-3,20-dione(CAS DataBase Reference)
• NIST Chemistry Reference: 9beta,10alpha-pregn-4-ene-3,20-dione(2755-10-4)
• EPA Substance Registry System: 9beta,10alpha-pregn-4-ene-3,20-dione(2755-10-4)

Safety Data

• Hazardous Substances Data: 2755-10-4(Hazardous Substances Data)

Usage

Uses

Retroprogesterone is employed as a combine menopause hormonal therapy, to ameliorate the risk of breast cancer in postmenopausal women.

Synthetic route

dydrogesterone (601-33-2, 1162-56-7, 2640-38-2, 3795-24-2, 25093-47-4, 152-62-5) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
With hydrogen; 5% Pd/CaCO3 In toluene for 1h;	88%
With hydrogen; 5 wt% palladium on calcium carbonate In toluene for 1h;	88%

4-(diethylamino)butan-2-one (3299-38-5) + sodium tert-pentoxide (14593-46-5) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
In benzene

(S)-1-((4aS,4bR,6aS,7S,9aS,9bS)-4a,6a-dimethyl-2-oxo-2,3,4,4a,4b,5,6,6a,7,8,9,9a,9b,10-tetradecahydroindeno[5,4-f]chromen-7-yl)ethyl acetate → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: tetrahydrofuran / 0.5 h / -35 - -25 °C 2: sodium hydroxide; water / methanol / 1 h / 65 °C 3: 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione / Isopropyl acetate / 6 h / 60 - 88 °C View Scheme

(8S,9R,10S,13S,14S,17S)-17-((S)-1-hydroxyethyl)-10,13-dimethyl-1,2,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-3H-cyclopenta[a]phenanthren-3-one → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
With 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione In Isopropyl acetate at 60 - 88℃; for 6h;

(3S,3aS,5aR,6R,9aR,9bS)-3-((S)-1-hydroxyethyl)-3a,6-dimethyldodecahydro-7H-cyclopenta[a]naphthalen-7-one → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions

Yield

Multi-step reaction with 6 steps 1.1: tert-Amyl alcohol; sodium hydroxide / 1 h / 50 °C / Inert atmosphere 1.2: 16.5 h / 50 °C 2.1: sodium hydroxide; water; N-benzyl-trimethylammonium hydroxide / 6 h / Reflux 3.1: 1.5 h / 135 °C 3.2: 1.5 h / Reflux 4.1: tetrahydrofuran / 0.5 h / -35 - -25 °C 5.1: sodium hydroxide; water / methanol / 1 h / 65 °C 6.1: 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione / Isopropyl acetate / 6 h / 60 - 88 °C View Scheme

3-((3S,3aS,5aR,6S,9aS,9bS)-3-((S)-1-hydroxyethyl)-3a,6-dimethyl-7-oxododecahydro-1H-cyclopenta[a]naphthalen-6-yl)propanenitrile → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 5 steps 1.1: sodium hydroxide; water; N-benzyl-trimethylammonium hydroxide / 6 h / Reflux 2.1: 1.5 h / 135 °C 2.2: 1.5 h / Reflux 3.1: tetrahydrofuran / 0.5 h / -35 - -25 °C 4.1: sodium hydroxide; water / methanol / 1 h / 65 °C 5.1: 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione / Isopropyl acetate / 6 h / 60 - 88 °C View Scheme

3-((3S,3aS,5aR,6S,9aS,9bS)-3-((S)-1-hydroxyethyl)-3a,6-dimethyl-7-oxododecahydro-1H-cyclopenta[a]naphthalen-6-yl)propanoic acid → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: 1.5 h / 135 °C 1.2: 1.5 h / Reflux 2.1: tetrahydrofuran / 0.5 h / -35 - -25 °C 3.1: sodium hydroxide; water / methanol / 1 h / 65 °C 4.1: 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione / Isopropyl acetate / 6 h / 60 - 88 °C View Scheme

4-(diethylamino)butan-2-one (3299-38-5) + 4-diethylaminobutan-3-one (90226-41-8) + 20β-hydroxy-9β,10β-desA-pregnan-5-one → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
With sodium hydroxide; sodium ethanolate; sodium In ethanol; acetic acid

Des-A-17α-Δ9-pregnen-5,20-dion (10072-88-5) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: sodium tetrahydroborate; methanol / -55 °C 2.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 3.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 3.2: 1 h / 50 - 55 °C 4.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme
Multi-step reaction with 5 steps 1.1: sodium tetrahydroborate / methanol 2.1: manganese(IV) oxide / dichloromethane / 20 - 55 °C 3.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 4.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 4.2: 1 h / 50 - 55 °C 5.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

C17H28O2 → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: manganese(IV) oxide / dichloromethane / 20 - 55 °C 2.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 3.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 3.2: 1 h / 50 - 55 °C 4.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

C17H26O2 → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 2.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 2.2: 1 h / 50 - 55 °C 3.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

C17H28O2 → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 1.2: 1 h / 50 - 55 °C 2.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

20β-hydroxy-9β,10α-pregn-4-en-3-one (4243-72-5) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
With chromium(VI) oxide; sulfuric acid In water; acetone at -10 - -5℃;

Progesterone (57-83-0) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 7 steps 1.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 120 °C 2.1: rhodium(III) chloride hydrate; sodium periodate / tetrachloromethane; acetonitrile; water 3.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 80 °C 4.1: sodium tetrahydroborate; methanol / -55 °C 5.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 6.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 6.2: 1 h / 50 - 55 °C 7.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme
Multi-step reaction with 8 steps 1.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 120 °C 2.1: rhodium(III) chloride hydrate; sodium periodate / tetrachloromethane; acetonitrile; water 3.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 80 °C 4.1: sodium tetrahydroborate / methanol 5.1: manganese(IV) oxide / dichloromethane / 20 - 55 °C 6.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 7.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 7.2: 1 h / 50 - 55 °C 8.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

pregna-1,4-diene-3,20-dione (1162-54-5) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 6 steps 1.1: rhodium(III) chloride hydrate; sodium periodate / tetrachloromethane; acetonitrile; water 2.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 80 °C 3.1: sodium tetrahydroborate; methanol / -55 °C 4.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 5.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 5.2: 1 h / 50 - 55 °C 6.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme
Multi-step reaction with 7 steps 1.1: rhodium(III) chloride hydrate; sodium periodate / tetrachloromethane; acetonitrile; water 2.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 80 °C 3.1: sodium tetrahydroborate / methanol 4.1: manganese(IV) oxide / dichloromethane / 20 - 55 °C 5.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 6.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 6.2: 1 h / 50 - 55 °C 7.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

5,20-Dioxo-1,5-seco-2,3,4-trisnor-pregnan-1-saeure (17955-33-8) → (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4)

Conditions	Yield
Multi-step reaction with 5 steps 1.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 80 °C 2.1: sodium tetrahydroborate; methanol / -55 °C 3.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 4.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 4.2: 1 h / 50 - 55 °C 5.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme
Multi-step reaction with 6 steps 1.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / toluene / 20 - 80 °C 2.1: sodium tetrahydroborate / methanol 3.1: manganese(IV) oxide / dichloromethane / 20 - 55 °C 4.1: Rh/Al2O3; hydrogenchloride; hydrogen / water; ethanol / 20 °C 5.1: sodium hydroxide / tert-butyl alcohol / 0.5 h / 20 - 55 °C / Inert atmosphere 5.2: 1 h / 50 - 55 °C 6.1: chromium(VI) oxide; sulfuric acid / water; acetone / -10 - -5 °C View Scheme

hydrogen cyanide (74-90-8) + (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 20-cyano-20-hydroxy-9beta,10alpha-pregna-4-ene-3-one (22641-37-8)

Conditions	Yield
With triethylamine In methanol at -8 - -3℃; for 48.25h;	100%
With triethylamine In ethanol

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 1-Dehydroretroprogesteron

Conditions	Yield
With 2,3-dicyano-5,6-dichloro-p-benzoquinone In benzene Heating;

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 21-F-Retroprogesteron

Conditions	Yield
(i) I2, MeOH, THF, (ii) AgF, CaF2, MeCN; Multistep reaction;

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6β-hydroxy-9β,10α-retroprogesterone

Conditions	Yield
With Cephalosporium aphidicola In ethanol for 72h;	93 mg

Bromotrichloromethane (75-62-7) + (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6β-Trichlormethyl-9β,10α-pregn-4-en-3,20-dion (4105-53-7)

Conditions	Yield
(i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732543/, Py; Multistep reaction;

carbon tetrabromide (558-13-4) + (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6β-Tribrommethyl-9β,10α-pregn-4-en-3,20-dion (4192-94-3)

Conditions	Yield
(i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py; Multistep reaction;

methanol (67-56-1) + (9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Methoxy-9β,10α-pregna-4,6-dien-3,20-dion

Conditions	Yield
With copper(ll) bromide

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 8-Hydroxy-9β.10α-pregnen-(4)-dion-(3.20) (23035-51-0)

Conditions	Yield
(microbiological transformation);

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 9-Hydroxy-Δ4-9β,10α-pregnen-3,20-dion (24495-52-1)

Conditions	Yield
(microbiological transformation);

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 18-cyano-9β,10α-pregna-4-ene-3,20-dione (22641-38-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: Et3N / ethanol 2: Pb(OAc)4, I2 / CH2Cl2; cyclohexane / Irradiation View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6α-Methyl-9β,10α-pregn-4-en-3,20-dion (4255-80-5)

Conditions	Yield
Multi-step reaction with 3 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: NaOH / methanol; CH2Cl2 3: H2, Et3N / Pd-SrCO3 / toluene; 2-methoxy-ethanol View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6β-Methyl-9β,10α-pregna-1,4-dien-3,20-dion

Conditions	Yield
Multi-step reaction with 5 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: NaOH / methanol; CH2Cl2 3: H2, Et3N / Pd-SrCO3 / toluene; 2-methoxy-ethanol 4: HCl / acetic acid 5: DDQ / dioxane View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Dichlormethyl-9β,10α-pregna-4,6-dien-3,20-dion

Conditions	Yield
Multi-step reaction with 2 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732543/, Py 2: ion-exchange resin - form> / CH2Cl2; aq. ethanol View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Dibrommethyl-9β,10α-pregna-4,6-dien-3,20-dion

Conditions	Yield
Multi-step reaction with 2 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: ion-exchange resin - form> / CH2Cl2; aq. ethanol View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Dichlormethylen-9β,10α-pregn-4-en-3,20-dion

Conditions	Yield
Multi-step reaction with 2 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732543/, Py 2: NaOH / methanol; CH2Cl2 View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Dibrommethylen-9β,10α-pregn-4-en-3,20-dion (4105-55-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: NaOH / methanol; CH2Cl2 View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Dibrommethylen-9β,10α-pregna-1,4-dien-3,20-dion

Conditions	Yield
Multi-step reaction with 3 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: NaOH / methanol; CH2Cl2 3: DDQ, HCl / dioxane View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6β-Methyl-9β,10α-pregn-4-en-3,20-dion (4422-50-8)

Conditions	Yield
Multi-step reaction with 4 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: NaOH / methanol; CH2Cl2 3: H2, Et3N / Pd-SrCO3 / toluene; 2-methoxy-ethanol 4: HCl / acetic acid View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 6-Methyl-9β,10α-pregna-4,6-dien-3,20-dion (4479-03-2)

Conditions	Yield
Multi-step reaction with 4 steps 1: (i) HC(OEt)3, TsOH, CHCl3, (ii) /BRN= 1732799/, Py 2: NaOH / methanol; CH2Cl2 3: H2, Et3N / Pd-SrCO3 / toluene; 2-methoxy-ethanol 4: DDQ, HCl / dioxane View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 18-Cyan-18,20β-epoxy-20-hydroxy-9β,10α-pregnen-(4)-on-(3)

Conditions	Yield
Multi-step reaction with 2 steps 1: Et3N / ethanol 2: Pb(OAc)4, I2 / CH2Cl2; cyclohexane / Irradiation View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 9,17β-Dihydroxy-Δ4-9β,10α-androsten-3-on (23015-96-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: (microbiological transformation) 2: (microbiological transformation) View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 10α-Pregna-4,9(11)-dien-3,20-dion (4085-88-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: (microbiological transformation) 2: collidine, MeSO2Cl / dimethylformamide View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 10α-Pregna-4,8-dien-3,20-dion (23102-60-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: (microbiological transformation) 2: collidine, MeSO2Cl / dimethylformamide View Scheme

(9β,10α)-pregn-4-ene-3,20-dione (2755-10-4) → 9-Hydroxy-Δ4-9β,10α-androsten-3,17-dion (23015-99-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: (microbiological transformation) 2: (microbiological transformation) 3: aq. CrO3, H2SO4 / acetone View Scheme

Upstream product

• 103000-97-1 1-(3,20-dioxo-5α-pregnan-2ξ-yl)-pyridinium; bromide 
• 64-19-7 acetic acid 
• 17503-05-8 (4α,5)epoxy-5α-pregnan-3,20-dione 
• 17597-24-9 (4β,5)-epoxy-5β-pregnan-3,20-dione 
• 163061-04-9 3β-hydroxy-14β,17α-pregn-5-en-20-one 
• 556-91-2 aluminum tri-tert-butoxide 
• 56-23-5 tetrachloromethane 
• 93-59-4 Perbenzoic acid 
• 67-66-3 chloroform 
• 7726-95-6 bromine 
• 753497-21-1 17β-Δ¹-5β-pregnen-3,20-dione 
• 57968-14-6 Δ¹-5β-pregnen-20-one 
• 1162-54-5 dl-Δ^1,2-pregnadiene-3,20-dione 
• 168609-36-7 3β-acetoxy-14β.17βH-pregnen-(5)-one-(20) 

Downstream Products

• 7093-55-2 5-pregnene-3,20-dione-3,20-bisethyleneketal 
• 58-22-0 testosterone 
• 16031-66-6 14-hydroxy-4-pregnene-3,20-dione 
• 63-05-8 Androstenedione 
• 145-14-2 (20S)-20-hydroxypregn-4-en-3-one 
• 68-96-2 17-hydroxyprogesterone 
• 600-57-7 (8S,9S,10R,11S,13S,14S,17S)-17-Acetyl-11-hydroxy-10,13-dimethyl-1,2,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-cyclopenta[a]phenanthren-3-one 
• 145-15-3 20α-hydroxyprogesterone 
• 7217-07-4 4-pregnene-3β,20β-diol 
• 80-75-1 11-alpha-hydroxyprogesterone 
• 599-14-4 12β,15α-Dihydroxyprogesterone 
• 1162-56-7 6-dehydroprogesterone 
• 1171-90-0 3,20-dioxo-pregna-1,4-dien-21-yl acetate 
• 897-06-3 Androsta-1,4-diene-3,17-dione 

Relevant articles and documents

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