75863-26-2

Basic information

• Product Name: pregna-1,4,16-triene-3,20-dione
• CAS NO: 75863-26-2
• Molecular Formula: C₂₁H₂₆O₂
• Molecular Weight: 310.4299
• Mol File: 75863-26-2.mol
• Article Data: 5

Chemical Properties

• Boiling Point: 463.5°C at 760 mmHg
• Flash Point: 172.4°C
• Density: 1.12g/cm³
• Vapor Pressure: 9E-09mmHg at 25°C
• Refractive Index: 1.573
• CAS DataBase Reference: pregna-1,4,16-triene-3,20-dione(CAS DataBase Reference)
• NIST Chemistry Reference: pregna-1,4,16-triene-3,20-dione(75863-26-2)
• EPA Substance Registry System: pregna-1,4,16-triene-3,20-dione(75863-26-2)

Safety Data

• Hazardous Substances Data: 75863-26-2(Hazardous Substances Data)

Upstream product

• 1162-53-4 16-dehydropregnenolone 
• 13952-06-2 17α-ethynyl-17β-hydroxy-1,4-androstadiene-3,11-dione 
• 566-65-4 dihydroprogesterone 
• 93206-68-9 (E)-17-(isocyanotosylmethylene)-3-methoxyandrosta-3,5,9⁽¹¹⁾-triene 
• 97674-02-7 tributyl(1-ethoxyvinyl)stannane 
• 148405-75-8 17-Iod-androsta-1,4,16-trien-3-on 

Downstream Products

• 1624-73-3 3-methoxy-19-norpregna-1,3,5⁽¹⁰⁾-trien-20-one 
• 1667-98-7 3-hydroxy-19-norpregna-1,3,5⁽¹⁰⁾-trien-20-one 

Relevant articles and documents

On a pregnane - 16 - ene - 3, 20 - dione steroid derivatives preparation method

The invention relates to a preparation method for a pregna-16-ene-3, 20-dione steroid derivative (II). The method is characterized by: reacting 17alpha-ethynyl-17beta-hydroxysteroid derivative I with a reagent A or an organic solvent containing the reagent A to obtaining the derivative (II). The reaction temperature ranges from 25DEG C to a solvent reflux temperature, and the reagent A is a solution formed by dissolving 5%-15% of phosphorus pentoxide in methanesulfonic acid.

Synthesis of 20-oxo steroids

The synthesis is described of a series of eighteen 16-dehydro-20-isocyano-20-sulfonylpregnanes (5 and 8-14) by C-20 alkylation of 17-androstanes 1-3.The geminal isocyano and sulfonyl groups at C-20 (compounds 5, 8-14) are removed by acid hydrolysis to provide a new entry into 20-oxo steroids (6, 15-19).The C-20 alkylation also includes halomethylation and alkoxymethylation to form 21-halo- and 21-alkoxy-16-dehydro-20-oxopregnanes, respectively.As an attractive alternative to acid hydrolysis, the isocyano group is first oxidized with Pb(OAc)4 to an isocyanato group prior to hydrolysis (of the geminal isocyanato and sulfonyl groups) to the same 20-oxo steroids.The latter conversion is carried out under non-acidic conditions at room temperature in a slurry of alumina in dichloromethane.

Preparation of 20-keto-Δ16 -steroids

A novel process for the preparation of 20-keto-Δ16 -steroids comprising reacting a 17-(isocyanosulfonylmethylene)-steroid with an alkylating agent QR4 wherein R4 is an organic group and Q is a group or atom readily displaced with a nucleophile to form a 20-isocyano-20-sulfonyl-Δ16 -steroid followed by hydrolysis which are intermediates for the preparation of corticosteroids and the novel intermediates formed therein.