24916-90-3

Basic information

• Product Name: 16-beta Methyl Epoxide
• Synonyms: (9b,11b,16a)-9,11-epoxy-17,21-dihydroxy-16-methyl-pregna-1,4-diene-3,20-dione;9BETA,11BETA-EPOXY-17,21-DIHYDROXY-16ALPHA-METHYLPREGNA-1,4-DIENE-3,20-DIONE;9,11B-EPOXY-17,21-DIHYDROXY-16A-METHYL-9B-PREGNA-1,4-DIENE-3,20-DIONE;9,11BETA-EPOXY-17,21-DIHYDROXY-16ALPHA-METHYL-9BETA-PREGNA-1,4-DIENE-3,20-DIONE;8DM;16-ALPHA METHYL EPOXIDE;9beta,11beta-epoxy-17,21-dihydroxy-16beta-methylpregna-1,4-diene-3,20-dione;16 α-Methyl epoxide(8-DM)
• CAS NO: 24916-90-3
• Molecular Formula: C₂₂H₂₈O₅
• Molecular Weight: 372.46
• EINECS: 213-563-4
• Product Categories: Pharmaceutical Raw Materials;Intermediates & Fine Chemicals;Pharmaceuticals;Steroids
• Mol File: 24916-90-3.mol
• Article Data: 5

Chemical Properties

• Melting Point: 210-220°C
• Boiling Point: 564.9 °C at 760 mmHg
• Flash Point: 198°C
• Appearance: pale-yellow solid
• Density: 1.32
• Vapor Pressure: 4.09E-15mmHg at 25°C
• Refractive Index: 1.616
• Storage Temp.: Refrigerator
• Solubility: Chloroform (Slightly, Heated, Sonicated), DMSO (Slightly, Sonicated), Methanol (
• PKA: 12.56±0.70(Predicted)
• CAS DataBase Reference: 16-beta Methyl Epoxide(CAS DataBase Reference)
• NIST Chemistry Reference: 16-beta Methyl Epoxide(24916-90-3)
• EPA Substance Registry System: 16-beta Methyl Epoxide(24916-90-3)

Safety Data

• Hazardous Substances Data: 24916-90-3(Hazardous Substances Data)

Usage

Chemical Properties

Pale-Yellow Solid

Uses

A metabolite of Mometasone furoate.

Definition

Pyrethrolone ester of chrysanthemumdicarboxylic acid. One of the four primary active insecticidal ingredients of pyrethrum flowers.

InChI:InChI=1/C22H28O5/c1-12-8-16-15-5-4-13-9-14(24)6-7-19(13,2)22(15)18(27-22)10-20(16,3)21(12,26)17(25)11-23/h6-7,9,12,15-16,18,23,26H,4-5,8,10-11H2,1-3H3

Synthetic route

C26H33BrO8 → 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3)

Conditions	Yield
With sodium hydroxide In methanol; dichloromethane at 0 - 5℃;	93.3%

17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate (2884-51-7) → 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3)

Conditions	Yield
With sodium hydroxide In methanol at -10 - -5℃; for 2h; Reagent/catalyst; Temperature;	84%
With water; sodium hydroxide In methanol; dichloromethane at -5 - 0℃; for 3h;

11α,17,21-trihydroxy-16α-methyl-pregna-1,4-diene-3,20-dione (78761-59-8) → 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3)

Conditions	Yield
Multi-step reaction with 4 steps 1: triethylamine / dichloromethane / -15 °C 2: phosphorus pentachloride / tetrahydrofuran / -85 °C 3: perchloric acid; 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione / water; N,N-dimethyl-formamide / 1 h / 20 °C 4: sodium hydroxide / dichloromethane; methanol / 0 - 5 °C View Scheme

Carbonic acid 2-((8S,9S,10R,11R,13S,14S,16R,17R)-11,17-dihydroxy-10,13,16-trimethyl-3-oxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxo-ethyl ester ethyl ester → 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3)

Conditions	Yield
Multi-step reaction with 3 steps 1: phosphorus pentachloride / tetrahydrofuran / -85 °C 2: perchloric acid; 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione / water; N,N-dimethyl-formamide / 1 h / 20 °C 3: sodium hydroxide / dichloromethane; methanol / 0 - 5 °C View Scheme

17α-hydroxy-16α-methyl-21-ethoxycarbonyloxypregna-1,4,9(11)-triene-3,20-dione (89561-92-2) → 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3)

Conditions	Yield
Multi-step reaction with 2 steps 1: perchloric acid; 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione / water; N,N-dimethyl-formamide / 1 h / 20 °C 2: sodium hydroxide / dichloromethane; methanol / 0 - 5 °C View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 9,11-epoxy-17α-hydroxy-16α-methyl-3-oxandrosta-1,4-diene-17β-carboxylic acid (159264-49-0)

Conditions	Yield
With periodic acid In tetrahydrofuran; water at 0 - 5℃; for 2h;	98.7%

acetic anhydride (108-24-7) + 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate (2884-51-7)

Conditions	Yield
With potassium acetate In ISOPROPYLAMIDE at 20℃; for 2h;	98%

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 21-chloro-17α-hydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (83881-08-7)

Conditions	Yield
With Vilsmeier reagent In tetrahydrofuran Reagent/catalyst; Solvent; Inert atmosphere;	86%
Multi-step reaction with 2 steps 1: triethylamine; 4-(dimethylamino)pyridine / CH2Cl2 / 0 - 5 °C 2: CH2Cl2; methanol / 3.5 h / 40 - 42 °C View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) + methanesulfonyl chloride (124-63-0) → 17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-methanesulfonate (223776-47-4)

Conditions	Yield
With triethylamine In tetrahydrofuran for 4h; Ambient temperature;	84%
With pyridine at -5 - 0℃; for 5h;

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 21-chloro-17α-hydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (83881-08-7) + 9β,11β-epoxy-17α-hydroxy-17β-(4-(R)-hydroxy-2,2-dioxido-1,2-oxathiolan-4-yl)-16α-methylandrosta-1,4-diene-3-one (223776-51-0)

Conditions	Yield
With dmap; methanesulfonyl chloride In dichloromethane for 4h; Heating;	A 69% B 1.1%

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) + methanesulfonyl chloride (124-63-0) → 21-chloro-17α-hydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (83881-08-7) + 9β,11β-epoxy-17α-hydroxy-17β-(4-(R)-hydroxy-2,2-dioxido-1,2-oxathiolan-4-yl)-16α-methylandrosta-1,4-diene-3-one (223776-51-0)

Conditions	Yield
With dmap In dichloromethane for 4h; Heating;	A 69% B 1.1%

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → C22H28O6 (134429-25-7)

Conditions	Yield
With selenium(IV) oxide In 1,4-dioxane at 80℃; for 1h;	33.5%

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) + p-toluenesulfonyl chloride (98-59-9) → 9β,11β-epoxy-17α,21-dihydroxy-16α-methyl-1,4-pregnadien-3,20-dione 21-tosylate

Conditions	Yield
With dmap; triethylamine In dichloromethane at 0 - 5℃;
With triethylamine hydrochloride In dichloromethane at -5 - 5℃; for 9h;

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → mometasone (105102-22-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: 69 percent / 4-DMAP, CH3SO2Cl / CH2Cl2 / 4 h / Heating 2: 83 percent / conc. HCl / acetic acid / 3 h / Ambient temperature View Scheme
Multi-step reaction with 2 steps 1: 69 percent / 4-DMAP / CH2Cl2 / 4 h / Heating 2: 83 percent / conc. HCl / acetic acid / 3 h / Ambient temperature View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → Mometasone furoate (83919-23-7)

Conditions	Yield
Multi-step reaction with 3 steps 1: 69 percent / 4-DMAP, CH3SO2Cl / CH2Cl2 / 4 h / Heating 2: 3.44 g / Et3N, 4-DMAP / CH2Cl2 / 6 h / Ambient temperature 3: 83 percent / conc. HCl / acetic acid / 3 h / Ambient temperature View Scheme
Multi-step reaction with 3 steps 1: 69 percent / 4-DMAP / CH2Cl2 / 4 h / Heating 2: 3.44 g / Et3N, 4-DMAP / CH2Cl2 / 6 h / Ambient temperature 3: 83 percent / conc. HCl / acetic acid / 3 h / Ambient temperature View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 9,11-Epoxidemometasone furoate (83881-09-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 69 percent / 4-DMAP, CH3SO2Cl / CH2Cl2 / 4 h / Heating 2: 3.44 g / Et3N, 4-DMAP / CH2Cl2 / 6 h / Ambient temperature View Scheme
Multi-step reaction with 2 steps 1: 69 percent / 4-DMAP / CH2Cl2 / 4 h / Heating 2: 3.44 g / Et3N, 4-DMAP / CH2Cl2 / 6 h / Ambient temperature View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 9β,11β-epoxy-16α-methyl-17α,21-oxidopregna-1,4-diene-3,20-dione

Conditions	Yield
Multi-step reaction with 2 steps 1: 84 percent / Et3N / tetrahydrofuran / 4 h / Ambient temperature 2: 80 percent / DBU / CH2Cl2 / 2 h / Heating View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 17β-(2,2-dioxido-3,4-dehydro-1,2-oxathiolan-4-yl)-9β,11β-epoxy-17α-hydroxy-16α-methylandrosta-1,4-dien-3-one 17-(2-furoate) (223776-50-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1.1 percent / 4-DMAP, CH3SO2Cl / CH2Cl2 / 4 h / Heating 2: 10 mg / 4-DMAP, Et3N / CH2Cl2 / 5 h / Ambient temperature View Scheme
Multi-step reaction with 2 steps 1: 1.1 percent / 4-DMAP / CH2Cl2 / 4 h / Heating 2: 10 mg / 4-DMAP, Et3N / CH2Cl2 / 5 h / Ambient temperature View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 9α-chloro-11β,17α-dihydroxy-17β-(2,2-dioxido-3,4-dehydro-1,2-oxathiolan-4-yl)-16α-methylandrosta-1,4-dien-3-one 17-(2-furoate)

Conditions	Yield
Multi-step reaction with 3 steps 1: 1.1 percent / 4-DMAP, CH3SO2Cl / CH2Cl2 / 4 h / Heating 2: 10 mg / 4-DMAP, Et3N / CH2Cl2 / 5 h / Ambient temperature 3: 87 percent / conc. HCl / acetic acid / 2 h / Ambient temperature View Scheme
Multi-step reaction with 3 steps 1: 1.1 percent / 4-DMAP / CH2Cl2 / 4 h / Heating 2: 10 mg / 4-DMAP, Et3N / CH2Cl2 / 5 h / Ambient temperature 3: 87 percent / conc. HCl / acetic acid / 2 h / Ambient temperature View Scheme

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-(4-dimethylaminopyridinium methanesulfonate)

Conditions	Yield
Multi-step reaction with 2 steps 1: 84 percent / Et3N / tetrahydrofuran / 4 h / Ambient temperature 2: 91 percent / CH2Cl2 / 3 h / Heating View Scheme

t-butyldimethylsiyl triflate (69739-34-0) + 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → 9β,11β-epoxy-3,21-di(t-butyldimethylsilyloxy)-17α-hydroxy-16α-methylpregna-1,3,5-triene-20-one

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In dichloromethane at -4 - 20℃; for 0.25h;

dichloromethane (75-09-2) + 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) + p-toluenesulfonyl chloride (98-59-9) → 21-chloro-17α-hydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (83881-08-7)

Conditions	Yield
With triethylamine In methanol; water

methanol-dichloromethane + 17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) → epoxyparamethasone (23961-95-7)

Conditions	Yield
methanolic potassium hydroxide

17α,21-dihydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (24916-90-3) + p-toluenesulfonyl chloride (98-59-9) → 21-chloro-17α-hydroxy-9β,11β-oxido-16α-methylpregna-1,4-diene-3,20-dione (83881-08-7)

Conditions	Yield
With triethylamine In methanol; dichloromethane; water

Upstream product

• 2884-51-7 17α,21-dihydroxy-9β,11β-epoxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate 
• 89561-92-2 17α-hydroxy-16α-methyl-21-ethoxycarbonyloxypregna-1,4,9(11)-triene-3,20-dione 
• 78761-59-8 11α,17,21-trihydroxy-16α-methyl-pregna-1,4-diene-3,20-dione 

Downstream Products

• 23961-95-7 epoxyparamethasone 
• 223776-49-6 9α-chloro-11β,17α-dihydroxy-17β-(2,2-dioxido-3,4-dehydro-1,2-oxathiolan-4-yl)-16α-methylandrosta-1,4-dien-3-one 17-(2-furoate) 
• 83881-09-8 9,11-Epoxidemometasone furoate 
• 83919-23-7 Mometasone furoate 

Relevant articles and documents

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