26360-40-7

Upstream product

• 1778-02-5 Pregnenolone acetate 
• 2723-07-1 5-Bromo-6β-hydroxy-20-oxo-5α-pregnan-3β-yl acetate 
• 64-19-7 acetic acid 
• 4777-61-1 3α,5-Cyclo-6β,19-epoxy-5α-pregnan-20-on 
• 15387-47-0 3α,5-cyclo-5α-pregnan-6β-ol-20-one 
• 6885-40-1 3β-toluene-4-sulfonyloxy-pregn-5-en-20-one 
• 145-13-1 Pregnenolone 
• 113687-72-2 3β,19-diacetoxy-5-hydroxy-5β-androstane-17β-carboxylic acid 
• 115208-97-4 3β,19-diacetoxy-21-diazo-5-hydroxy-5β-pregnan-20-one 
• 115209-82-0 3β,19-diacetoxy-5-hydroxy-5β-pregnan-20-one 
• 41767-48-0 3β-acetoxy-5-bromo-6β,19-epoxy-5α-pregnan-20-one 
• 41767-48-0 5-Bromo-20-oxo-6β,19-epoxy-5α-pregnan-3β-yl acetate 
• 101524-60-1 20-oxopregn-5-ene-3β,19-diyl diacetate 

Downstream Products

• 845724-76-7 Acetic acid (3S,5S,8S,9S,10R,13S,14S,17S)-13-methyl-17-(2-methyl-[1,3]dioxolan-2-yl)-3-(toluene-4-sulfonyloxy)-hexadecahydro-cyclopenta[a]phenanthren-10-ylmethyl ester 
• 596-63-4 19-Hydroxyprogesterone 
• 75220-37-0 19-oxo-deoxycorticosterone 
• 88378-35-2 19-oxo-11-deoxycorticosterone acetate 
• 4682-70-6 19-Nordeoxycorticosterone 
• 2394-23-2 19,21-dihydroxypregn-4-ene-3,20-dione 
• 6901-40-2 19,21-dihydroxypregn-4-ene-3,20-dione 21-acetate 

Relevant academic research and scientific papers

Scalable Synthesis of Cyclocitrinol

A 10-step synthesis of the C25 steroid natural product cyclocitrinol from inexpensive, commercially available pregnenolone is reported. This synthesis features a biomimetic cascade rearrangement to efficiently construct the challenging bicyclo[4.4.1] A/B ring system, which enabled a gram-scale synthesis of the bicyclo[4.4.1] enone intermediate 18 in only nine steps. This work also provides experimental support for the biosynthetic origin of cyclocitrinol.

Facile Access to Bridged Ring Systems via Point-to-Planar Chirality Transfer: Unified Synthesis of Ten Cyclocitrinols

Bridged ring systems are found in a wide variety of biologically active molecules including pharmaceuticals and natural products. However, the development of practical methods to access such systems with precise control of the planar chirality presents considerable challenges to synthetic chemists. In the context of our work on the synthesis of cyclocitrinols, a family of steroidal natural products, we herein report the development of a point-to-planar chirality transfer strategy for preparing bridged ring systems from readily accessible fused ring systems. Inspired by the proposed pathway for biosynthesis of cyclocitrinols from ergosterol, our strategy involves a bioinspired cascade rearrangement, which enabled the gram-scale synthesis of a common intermediate in nine steps and subsequent unified synthesis of 10 cyclocitrinols in an additional one to three steps. Our work provides experimental support for the proposed biosynthetic pathway and for the possible interrelationships between members of the cyclocitrinol family. In addition to being a convenient route to 5(10→19)abeo-steroids, our strategy also offers a generalized approach to bridged ring systems via point-to-planar chirality transfer. Mechanistic investigations suggest that the key cascade rearrangement involves a regioselective ring scission of a cyclopropylcarbinyl cation rather than a direct Wagner-Meerwein rearrangement.

Sn(OTf)2 as an effective lewis acid in reactions of cyclopropyl ketones with acetic anhydride: Application in the synthesis of a 19-Nor-B-homo steroid

Attempts to convert 3β-acetoxy-5,19-cyclo-pregna-6,20-dione (8) into a cyclocitrinol-related steroid with a bicyclo[4.4.1]-undecane AB-ring substructure through a Lewis acid-assisted fragmentation failed. Instead, treating 8 with an excess of Ac2/su

An Improved Route to 19-Hydroxypregn-4-ene-3,20-dione and Synthesis of its Analogue

3β-Acetoxy-5-bromo-6β,19-epoxy-5α-pregnane-20-one is more reliably converted into 19-hydroxyprogesterone via reductive opening of the epoxide to give 3β-acetoxy-19-hydroxypregn-5-en-20-one than by a previously published procedure. 19-Hydroxyprogesterone has been converted into its analogue in good yield.