Low-calcemic, efficacious, 1alpha,25-dihydroxyvitamin D3 analog QW-1624F2-2: calcemic dose-response determination, preclinical genotoxicity testing, and revision of A-ring stereochemistry.

Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA.
Steroids (Impact Factor: 2.72). 10/2004; 69(11-12):757-62. DOI: 10.1016/j.steroids.2004.09.004
Source: PubMed

ABSTRACT Based on an X-ray crystal structure determination, the A-ring stereochemistry of hybrid analog QW-1624F2-2 (1alpha-hydroxymethyl-16-ene-24,24-difluoro-25-hydroxy-26,27-bis-homovitamin D3) is revised to be 1alpha-CH2OH-3beta-OH. This analog is shown to be approximately 80-100 times less calciuric than the natural hormone 1alpha,25-dihydoxyvitamin D3. This analog is shown also to be non-genotoxic in three different standard assays.

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