Convergent Approaches and Biological Activity of C1 and/or C3 Mono or Diamino Derivatives of 1α,25‐Dihydroxy‐19‐ <i>nor</i> ‐vitamin D ₃ . Key Enzymatic Desymmetrization of A‐Ring Synthon Precursor

Three novel 19-nor-1α,25-dihydroxyvitamin D3 derivatives modified at C1 and/or C3 with an amino group were synthesized to study the influence of substitution one or both hydroxyl groups A-ring by on affinity for vitamin D receptor (VDR) and binding protein (hDBP), also antiproliferative activity. The precursors prepared from cis,cis-1,3,5-cyclohexanetriol applying a desymmetrization reaction prochiral 1,3-diol catalyzed Pseudomonas cepacia lipase as key step. structural elucidation diastereoisomers unambiguously assigned NMR spectroscopy.