New 1α,25-Dihydroxy-19-norvitamin D<sub>3</sub> Compounds of High Biological Activity: Synthesis and Biological Evaluation of 2-Hydroxymethyl, 2-Methyl, and 2-Methylene Analogues
作者:Rafal R. Sicinski、Jean M. Prahl、Connie M. Smith、Hector F. DeLuca
DOI:10.1021/jm9802618
日期:1998.11.1
New highly active isomers of the natural hormone 1alpha, 25-dihydroxyvitamin D3 possessing an exomethylene group at the 2-position were prepared in a convergent manner, starting with (-)-quinic acid and the corresponding (20R)- and (20S)-25-hydroxy Grundmann ketones. These 2-methylene-19-norvitamins were efficiently converted to the 2-methyl and 2-hydroxymethyl derivatives, some of which exhibited
以(-)-奎尼酸和相应的(20R)-和(20S)-为起始原料,以聚合方式制备了天然激素1α,25-二羟基维生素D3在2-位具有异亚甲基的新的高活性异构体。 25-羟基Grundmann酮。这些2-亚甲基-19-norvitamins被有效地转换为2-甲基和2-羟甲基衍生物,其中一些表现出明显的体内生物活性。A环取代基的构型通过1H NOE差异光谱以及自旋解耦实验确定。已经确定,由于其大的构象自由能,C-2上的大的甲基和羟甲基取代基主要占据赤道位置。此外,在1alpha,25-(OH)2D3中进行了C(10)-C(19)双键的羟基化反应,得到1alpha,19,25-三羟基-10,19-二氢维生素D3衍生物,其中由于空间原因,C-10处的羟甲基取代基被迫占据轴向位置。结果,合成了维生素D3类似物,其中生物活性所需的1α-羟基几乎是轴向的或赤道取向的,这是因为单个A环椅子构象的稳定性。评估了合