Synthesis of new 18-substituted analogues of calcitriol using a photochemical remote functionalization.
A novel convergent synthetic approach to new analogues of calcitriol modified at the C-18 position is reported. The key step in the synthesis is the 20-hydroxyl-directed photochemical iodination of the 18-methyl group in the presence of (diacetoxyiodo)benzene. Using this methodology, two new analogues of calcitriol were prepared: the first contains a hydroxylated alkyl side chain attached at C-18 with the natural side chain replaced by an isopropylidene group; the second is a conformationally locked analogue due to an extra oxacycle between the C-18 and C-20 positions.
Cornella
Iván
I
Departamento de Química Fundamental, Universidade da Coruña, E-15071 A Coruña, Spain.
Pérez Sestelo
José
J
Mouriño
Antonio
A
Sarandeses
Luis A
LA
D001667:Binding, Competitive; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010777:Photochemistry; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014961:X-Ray Diffraction
D002117:Calcitriol