3747-91-9Relevant articles and documents
Carbonyl-Directed Aliphatic Fluorination: A Special Type of Hydrogen Atom Transfer Beats out Norrish II
Ghorbani, Fereshte,Harry, Stefan Andrew,Capilato, Joseph N.,Pitts, Cody Ross,Joram, Jacob,Peters, Garvin N.,Tovar, John D.,Smajlagic, Ivor,Siegler, Maxime A.,Dudding, Travis,Lectka, Thomas
supporting information, p. 14710 - 14724 (2020/10/13)
Recently, our group reported that enone and ketone functional groups, upon photoexcitation, can direct site-selective sp3 C-H fluorination in terpenoid derivatives. How this transformation actually occurred remained mysterious, as a significant number of mechanistic possibilities came to mind. Herein, we report a comprehensive study describing the reaction mechanism through kinetic studies, isotope-labeling experiments, 19F NMR, electrochemical studies, synthetic probes, and computational experiments. To our surprise, the mechanism suggests intermolecular hydrogen atom transfer (HAT) chemistry is at play, rather than classical Norrish hydrogen atom abstraction as initially conceived. What is more, we discovered a unique role for photopromoters such as benzil and related compounds that necessitates their chemical transformation through fluorination in order to be effective. Our findings provide documentation of an unusual form of directed HAT and are of crucial importance for defining the necessary parameters for the development of future methods.
A method for avoiding heavy metal residual acetate preparation method
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Paragraph 0017; 0061; 0062; 0063; 0064, (2017/08/25)
The invention discloses a novel method for preparing abiraterone acetate. The method comprises the following steps of: hydroxyl protection, Aldol reaction, dehydration reaction, deprotection and acetylation. According to the method, the heavy-metal reagent, the strict anhydrous and anaerobic equipment and the expensive alkyl boron reagent are not used, thus the cost is reduced greatly. The method is suitable for mass industrial production.
Methods of preparing pharmaceutical solid state forms
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Page/Page column 41, (2016/05/19)
The invention provides and describes solid state 17α-ethynyl-5α-androstane-3α,17β-diol including amorphous and crystalline forms and specific polymorphic forms thereof. Anhydrates and solvates of 17α-ethynyl-5α-androstane-3α,17β-diol include Form III anhydrate and Form I solvate. The invention further relates to solid and suspension formulations containing 17α-ethynyl-5α-androstane-3α,17β-diol in a described solid state form and use of the formulations to treat cancers or precancers such as prostate cancer or breast cancer in subjects or human patients. The invention also relates to methods to make liquid formulations from solid state forms of 17α-ethynyl-5α-androstane-3α,17β-diol and uses of such formulations in treating the described conditions.
PROCESS FOR THE PREPARATION OF ABIRATERONE AND INTERMEDIATES THEREOF
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Paragraph 0149, (2015/02/05)
The present invention provides intermediates for preparing abiraterone, and processes for preparing abiraterone and intermediates thereof. The intermediates include a compound of formula (IV): wherein R represents a hydroxy-protecting group.
METHODS AND COMPOUNDS FOR PREPARING 3ALPHA-OXYGEN SUBSTITUTED STEROIDS
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, (2012/09/05)
The invention relates to processes for preparing 3α-O-linked steroids including 3α-O-linked-androst-5-ene steroids and 3α-O-linked-5a-androstane steroids. In one process a 3α,4α-epoxy androst-5-en-17-one is predominately reduced at the epoxy moiety wherein reduction of the 3α,4α epoxy functional group occurs preferentially at position C4 with retention of configuration at position C3 to provide a 3α-O-linked-androst-5-ene steroid. In another process, conditions are provided for inversion of configuration of a 3β-hydroxy-androst-5-ene steroid by the Mitsunobu reaction to provide a 3α-O-linked-androst-5-ene steroid with reduced amounts of 3α,5α-cycloandrostane side-product impurities.
METHODS FOR PREPARING 17-ALKYNYL-7-HYDROXY STEROIDS AND RELATED COMPOUNDS
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Page/Page column 13; 14, (2009/12/28)
The invention relates to processes for preparing 17-alkynyl-7-hydroxy- steroids, such as 17-Ethynyl-10R13S-dimethyl 2,3,4,7,8R,9S, 10,11,12,13,14S,15,16,17-hexadecahydro-1 H-cyclopenta[a]phenanthrene- 3R,7R,17S-triol (also referred to as 17α-ethynyl-androst-5-ene-3β,7β,17β-triol), that are essentially free of process impurities having binding activity at nuclear estrogen receptors.