434-05-9

Basic information

• Product Name: Methenolone acetate
• Synonyms: 17-(acetyloxy)-1-methyl-,(5-alpha,17-beta)-androst-1-en-3-on;17-beta-hydroxy-1-methyl-5-alpha-androst-1-en-3-onacetate;17-beta-hydroxy-1-methyl-5-alpha-androst-1-en-3-oneacetate;nibal;premobolan;primobolan;primobolone;primonabol
• CAS NO: 434-05-9
• Molecular Formula: C₂₂H₃₂O₃
• Molecular Weight: 344.49
• EINECS: 207-097-0
• Product Categories: Steroids;Steroid and Hormone;methenolone series
• Mol File: 434-05-9.mol
• Article Data: 1

Chemical Properties

• Melting Point: 138-139°
• Boiling Point: 419.57°C (rough estimate)
• Flash Point: 189.9 °C
• Appearance: /
• Density: 1.0906 (rough estimate)
• Vapor Pressure: 5.54E-08mmHg at 25°C
• Refractive Index: 1.5000 (estimate)
• CAS DataBase Reference: Methenolone acetate(CAS DataBase Reference)
• NIST Chemistry Reference: Methenolone acetate(434-05-9)
• EPA Substance Registry System: Methenolone acetate(434-05-9)

Safety Data

• Hazardous Substances Data: 434-05-9(Hazardous Substances Data)

Usage

Description

Methenolone acetate (Brand name: Primobolan) is a synthetic, orally active anabolic-androgenic steroid and dihydrotestosterone (DHT) derivative. It can be used for the treatment of bone marrow disease and anemia. Methenolone acetate is known for its higher therapeutic efficiency and lower hepatic toxicity compared with its 17 alpha- alkylated analogs. However, it is frequently abused in human sports because of its capability of increasing muscle strength as well as promoting performance and aggressiveness. It is capable of enhancing performance in racehorses.

Chemical Properties

White Solid

Uses

Methenolone acetate is an anabolic steroid. This is a controlled substance.

References

Ho, Emmie N. M., et al. "Metabolic studies of methenolone acetate in horses." Analytica Chimica Acta 540.1(2005): 111-119. https://en.wikipedia.org/wiki/Metenolone_acetate

InChI:InChI=1/C22H32O3/c1-13-11-16(24)12-15-5-6-17-18-7-8-20(25-14(2)23)21(18,3)10-9-19(17)22(13,15)4/h11,15,17-20H,5-10,12H2,1-4H3/t15-,17-,18-,19-,20-,21-,22-/m0/s1

Synthetic route

17β-acetoxy-1-methyl-androsta-1,4-dien-3-one (1099-80-5) → 3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9)

Conditions	Yield
With thallium(III) nitrate trihydrate In diethylene glycol dimethyl ether for 24h; Ambient temperature;	8%

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-acetoxy-1-methyl-androsta-1,4-dien-3-one (1099-80-5)

Conditions	Yield
With diphenyl diselenide; iodosylbenzene In toluene at 80℃; for 4h;	80%
With thallium(III) acetate In acetic acid

formaldehyd (50-00-0) + 3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) + thiophenol (108-98-5) → 17β-acetyloxy-1-methyl-2-<(phenylthio)methyl>-5α-androst-1-en-3-one (127557-42-0)

Conditions	Yield
In water at 110℃; for 24h;	61%

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-Hydroxy-1-methyl-5α-androst-1-en

Conditions	Yield
With lithium aluminium tetrahydride In diethyl ether

Isopropenyl acetate (108-22-5) + 3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → Acetic acid (5S,8R,9S,10S,13S,14S,17S)-17-acetoxy-10,13-dimethyl-1-methylene-4,5,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester (2098-47-7)

Conditions	Yield
With hydrogen cation

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-Acetoxy-1-methyl-Δ1-5α-androstenol-(3β)

Conditions	Yield
With lithium tri-t-butoxyaluminum hydride

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) + acetic anhydride (108-24-7) → Acetic acid (5S,8R,9S,10S,13S,14S,17S)-17-acetoxy-10,13-dimethyl-1-methylene-4,5,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester (2098-47-7)

Conditions	Yield
With hydrogen cation

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) + benzoyl chloride (98-88-4) → Benzoic acid (5S,8R,9S,10S,13S,14S,17S)-17-acetoxy-10,13-dimethyl-1-methylene-4,5,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester

Conditions	Yield
In toluene

diazomethane (186581-53-3, 908094-01-9) + 3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → A-Homo-4-oxo-1-methyl-17β-acetoxy-Δ1(2)-5α-androsten (1050-87-9)

Conditions	Yield
With aluminium trichloride In diethyl ether; benzene

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 1,2-dimethylandrosta-1,4-dien-3,17-dione (127557-30-6)

Conditions

Yield

Multi-step reaction with 5 steps 1: 61 percent / various solvent(s); H2O / 24 h / 110 °C 2: 73 percent / Raney nickel / acetone / 0.25 h / Heating 3: 78 percent / iodoxybenzene, diphenyl diselenide / toluene / 4 h / 80 °C 4: 94 percent / 3 percent potassium hydroxide / methanol / 4 h / Ambient temperature 5: 81 percent / chromium trioxide, conc. sulfuric acid / H2O; acetone / 0.25 h / Ambient temperature View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-hydroxy-1,2-dimethyl-5α-androst-1-en-3-one (6176-40-5)

Conditions	Yield
Multi-step reaction with 3 steps 1: 61 percent / various solvent(s); H2O / 24 h / 110 °C 2: 73 percent / Raney nickel / acetone / 0.25 h / Heating 3: 93 percent / 3 percent potassium hydroxide / methanol / 4 h / Ambient temperature View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 1,2-dimethyl-5α-androst-1-en-3,17-dione (127557-45-3)

Conditions	Yield
Multi-step reaction with 4 steps 1: 61 percent / various solvent(s); H2O / 24 h / 110 °C 2: 73 percent / Raney nickel / acetone / 0.25 h / Heating 3: 93 percent / 3 percent potassium hydroxide / methanol / 4 h / Ambient temperature 4: 86 percent / chromium trioxide, conc. sulfuric acid / H2O; acetone / 0.25 h / Ambient temperature View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-hydroxy-1,2-dimethylandrosta-1,4-dien-3-one (127557-44-2)

Conditions	Yield
Multi-step reaction with 4 steps 1: 61 percent / various solvent(s); H2O / 24 h / 110 °C 2: 73 percent / Raney nickel / acetone / 0.25 h / Heating 3: 78 percent / iodoxybenzene, diphenyl diselenide / toluene / 4 h / 80 °C 4: 94 percent / 3 percent potassium hydroxide / methanol / 4 h / Ambient temperature View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-acetyloxy-1,2-dimethyl-5α-androst-1-en-3-one (5984-09-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 61 percent / various solvent(s); H2O / 24 h / 110 °C 2: 73 percent / Raney nickel / acetone / 0.25 h / Heating View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-acetyloxy-1,2-dimethylandrosta-1,4-dien-3-one (127557-43-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: 61 percent / various solvent(s); H2O / 24 h / 110 °C 2: 73 percent / Raney nickel / acetone / 0.25 h / Heating 3: 78 percent / iodoxybenzene, diphenyl diselenide / toluene / 4 h / 80 °C View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → Acetic acid (5S,8R,9S,10S,13S,14S,17S)-1,10,13-trimethyl-4,5,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-3H-cyclopenta[a]phenanthren-17-yl ester

Conditions	Yield
Multi-step reaction with 2 steps 1: LiAlH4 / diethyl ether 2: Py View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 1-Chlormethyl-Δ1-androsten-17β-ol-3-on-17-acetat

Conditions	Yield
Multi-step reaction with 2 steps 1: H+ 2: (chlorination) View Scheme
Multi-step reaction with 2 steps 1: H+ 2: (chlorination) View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → Acetic acid (5S,8R,9S,10S,13S,14S,17S)-1-bromomethyl-10,13-dimethyl-3-oxo-4,5,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-3H-cyclopenta[a]phenanthren-17-yl ester

Conditions	Yield
Multi-step reaction with 2 steps 1: H+ 2: (bromination) View Scheme
Multi-step reaction with 2 steps 1: H+ 2: (bromination) View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-Acetoxy-1α-methyl-1,2β-methylen-5α-androstanol-(3β) (5902-14-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: Li 2: Zn-Cu / diethyl ether; 1,2-dimethoxy-ethane / Heating View Scheme

3-oxo-1-methyl-5α-androst-1-en-17β-yl acetate (434-05-9) → 17β-Acetoxy-1α-methyl-1.2β-methylen-5α-androstanon-(3)

Conditions	Yield
Multi-step reaction with 3 steps 1: Li 2: Zn-Cu / diethyl ether; 1,2-dimethoxy-ethane / Heating 3: CrO3, aq. H2SO4 / acetone View Scheme

Upstream product

• 1099-80-5 17β-acetoxy-1-methyl-androsta-1,4-dien-3-one 

Downstream Products

• 127557-42-0 17β-acetyloxy-1-methyl-2-<(phenylthio)methyl>-5α-androst-1-en-3-one 

Relevant articles and documents

Preparation of steroidal 1,4-dien-3-ones using thallium(III) nitrate (1)

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