75863-26-2

Upstream product

• 13952-06-2 17α-ethynyl-17β-hydroxy-1,4-androstadiene-3,11-dione 
• 1162-53-4 16-dehydropregnenolone 
• 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 academic research and scientific papers

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.

Δ16-20-Ketosteroids by C2-Elongation from Δ16-17-Substituted Steroids

Reactions of corticoid precursor steroids with a Δ16-double bond and iodine, trimethylsilyl, tributylstannyl or trifluoromethanesulfonyloxy groups in 17-position were studied with the aim of introducing an acyl substituent in 17-position.Starting with the 17-trimethylsilyl compounds, using acyl chlorides and AlCl3 as a catalyst, a mixture of chlorinated compounds were obtained, among others.Better results gave palladium-catalyzed reactions, such as the cross-coupling of 17-tributylstannyl compounds with acyl chlorides or the substitution of the 17-iodides or the 17-triflates by vinyl ethers.In the reaction of the 17-iodides, different protecting groups are tolerated; thus this method is of general use.No Δ16-17-triflates were obtained by the reaction of androsta-4-ene-3,17-dione or androsta-1,4-diene-3,17-dione with trifluoromethanesulfonyl anhydride.This is a limitation of the triflate method, which in the other cases gives the best yields (>80percent).

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.