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Synthesis of New 26,27-Difluoro- and 26,26,27,27-Tetrafluoro-25-hydroxyvitamin D: Effects of Terminal Fluorine Atoms on Biological Activity and Half-life. | LitMetric

AI Article Synopsis

  • Researchers synthesized two new fluorinated vitamin D analogues, 26,27-difluoro-25-hydroxyvitamin D and 26,26,27,27-tetrafluoro-25-hydroxyvitamin D, using a convergent method involving the Wittig-Horner coupling reaction.
  • The tetrafluorinated compound displayed a higher binding affinity to the vitamin D receptor and better resistance to metabolism than both the difluorinated analogue and the standard vitamin D compound.
  • Among the tested compounds, HF-25(OH)D exhibited the highest biological activity, showing a transactivation effect on the osteocalcin promoter that was 19 times greater than that of the natural vitamin D form.

Article Abstract

As an extension of our research on providing a chemical library of side-chain fluorinated vitamin D analogues, we newly designed and synthesized 26,27-difluoro-25-hydroxyvitamin D (1) and 26,26,27,27-tetrafluoro-25-hydroxyvitamin D (2) using a convergent method applying the Wittig-Horner coupling reaction between CD-ring ketones (13, 14) and A-ring phosphine oxide (5). The basic biological activities of analogues, 1, 2, and 26,26,26,27,27,27-hexafluoro-25-hydroxyvitamin D [HF-25(OH)D] were examined. Although the tetrafluorinated new compound 2 exhibited higher binding affinity for vitamin D receptor (VDR) and resistance to CYP24A1-dependent metabolism compared with the difluorinated 1 and its non-fluorinated counterpart 25-hydroxyvitamin D [25(OH)D], HF-25(OH)D showed the highest activity among these compounds. Osteocalcin promoter transactivation activity of these fluorinated analogues was tested, and it decreased in the order of HF-25(OH)D, 2, 1, and 25(OH)D in which HF-25(OH)D showed 19-times greater activity than the natural 25(OH)D.

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Source
http://dx.doi.org/10.1248/cpb.c23-00395DOI Listing

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