13-Methyl-substituted des-C,D analogs of (20S)-1α,25-dihydroxy-2-methylene-19-norvitamin D3 (2MD): Synthesis and biological evaluation
作者:Katarzyna Plonska-Ocypa、Rafal R. Sicinski、Lori A. Plum、Pawel Grzywacz、Jadwiga Frelek、Margaret Clagett-Dame、Hector F. DeLuca
DOI:10.1016/j.bmc.2008.11.082
日期:2009.2
from ester 21. The obtained α,β-unsaturated esters 22 and 23 served as convenient starting compounds to the syntheses of the corresponding chiral acyclic aldehydes, β,γ-unsaturated (28) and saturated (39 and 40), required for the final Wittig–Horner coupling with the anion of the phosphine oxide 29. After hydroxyl deprotection, the synthesized vitamin D analogs 11–13 and 32 were purified and biologically
(20的类似物小号)-1α,25-二羟基-2-亚甲基-19-去甲维生素d 3(2,为2Md)中,在C-13取代的,但缺乏C和d的环,在会聚合成制备,开始于手性酯14和氧化膦29。合成的维生素中的两种(11和32)是类似物,其中13-甲基构成不饱和片段的取代基,即C(13)-C(17)双键,而在其他两种情况下(12和13),甲基属于一个三元碳立体异构中心。这些研究的目的是进一步探索维生素D骨架“上部”的广泛修饰,以期找到具有潜在治疗价值的生物活性类似物。 商业化的(R)-(-)-甲基-3-羟基-2-甲基丙酸酯(14)通过六步转化为醇18(维生素D侧链片段)。随后的三步转化生成了醛20,该醛与衍生自酯21的阴离子进行了Still-Gennari HWE反应。获得的α,β-不饱和酯22和23可作为合成最终Wittig-Horner偶联所需的相应手性无环醛,β,γ-不饱和(28)和饱和(39和40