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Kinetics of Electrophilic Fluorination of Steroids and Epimerisation of Fluorosteroids.

ABSTRACT: Fluorinated steroids, which are synthesised by electrophilic fluorination, form a significant proportion of marketed pharmaceuticals. To gain quantitative information on fluorination at the 6-position of steroids, kinetics studies were conducted on enol ester derivatives of progesterone, testosterone, cholestenone and hydrocortisone with a series of electrophilic N-F reagents. The stereoselectivities of fluorination reactions of progesterone enol acetate and the kinetic effects of additives, including methanol and water, were investigated. The kinetics of epimerisation of 6?-fluoroprogesterone to the more pharmacologically active 6?-fluoroprogesterone isomer in HCl/acetic acid solutions are detailed.

SUBMITTER: Rozatian N

PROVIDER: S-EPMC7540021 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Kinetics of Electrophilic Fluorination of Steroids and Epimerisation of Fluorosteroids.

Rozatian Neshat N Harsanyi Antal A Murray Ben J BJ Hampton Alexander S AS Chin Emily J EJ Cook Alexander S AS Hodgson David R W DRW Sandford Graham G

Chemistry (Weinheim an der Bergstrasse, Germany) 20200825 52

Fluorinated steroids, which are synthesised by electrophilic fluorination, form a significant proportion of marketed pharmaceuticals. To gain quantitative information on fluorination at the 6-position of steroids, kinetics studies were conducted on enol ester derivatives of progesterone, testosterone, cholestenone and hydrocortisone with a series of electrophilic N-F reagents. The stereoselectivities of fluorination reactions of progesterone enol acetate and the kinetic effects of additives, inc ...[more]

PMID: 32267575

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