72498-89-6Relevant articles and documents
Improved synthesis of fluocinolone acetonide and process research of 6α,9α-fluorination
Tang, Jie,Zeng, Chunling,Xie, Longyong,Wang, Jinghua,Tian, Mi,Guo, Cancheng
supporting information, p. 110 - 112 (2018/01/26)
An efficient and improved synthetic route of fluocinolone acetonide with combination of bio-fermentation was developed from 21-acetyloxy-17α-hydroxy-4,9(11)-diene-3,20-dione (1a). Process of the 6α and 9α fluorination steps was studied, and it was observe
STEREOSELECTIVE METHOD OF PRODUCING 6ALPHA-FLUOROPREGNANES AND INTERMEDIARIES
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Page 9, (2008/06/13)
6α-fluorpregnanes (I), where the dotted line between positions 1 and 2 represents a single or double bond; R1 is OH, OCOR2, X, SO3R3, or an (R7)(R8)(R9)SiO- group, where X is halogen, R2 and R3 are C1-6 alkyl or phenyl optionally substituted by C1-4 alkyl, and R7, R8 and R9, equal or different, are C1-6 alkyl or phenyl optionally substituted by C1-4 alkyl, can be obtained by means of a high stereoselectivity process comprising reacting a 3-(trisubstituted)silyloxy-pregna-3,5-diene (IV) with a fluorinating agent selected among N-fluorosulfonimides and N-fluorosulfonamides. The 6α-fluorpregnanes (I) are intermediates for the synthesis of steroids useful as anti-inflammatory and anti-asthmatic agents.
Process for the preparation of 6-halo-pregnanes
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, (2008/06/13)
The invention relates to a new process for the preparation of 6α-halo-3-keto-Δ1,4 -pregnadiene-derivatives in two-steps-synthesis affording directly 6α-halo-derivatives by reacting 3-keto-9β,11β-oxido-Δ1,4 -pregnadiene-derivatives with a suitable acylating or etherifying agent to give the corresponding new 3-enol-derivatives which are finally halogenated by using a suitable halogenating agent.