Efficient Synthesis of 2-Modified 1α,25-Dihydroxy-19-norvitamin D<sub>3</sub> with Julia Olefination: High Potency in Induction of Differentiation on HL-60 Cells
作者:Keiichiro Ono、Akihiro Yoshida、Nozomi Saito、Toshie Fujishima、Shinobu Honzawa、Yoshitomo Suhara、Seishi Kishimoto、Takayuki Sugiura、Keizo Waku、Hiroaki Takayama、Atsushi Kittaka
DOI:10.1021/jo034787y
日期:2003.9.1
Six novel 2-substituted analogues of 1alpha,25-dihydroxy-19-norvitamin D(3), 6a,b-8a,b, were efficiently synthesized utilizing (-)-quinic acid as the A-ring precursor. The C2-modified A-rings were prepared as 4-alkylated (3R,5R)-3,5-dihydroxycyclohexanones 12-15 from (-)-quinic acid based on radical allylation at the C4 position of methyl (-)-quinicate. The new type of the CD-ring coupling partner
利用(-)奎尼酸作为A环前体有效合成了1alpha,25-dihydroxy-19-norvitamin D(3),6a,b-8a,b的六个新颖的2-取代类似物。基于在(-)-奎宁酸甲酯的C 4位上的自由基烯丙基化,由(-)-奎宁酸将C 2修饰的A-环制备为4-烷基化的(3R,5R)-3,5-二羟基环己酮12-15。由25-羟基Grundmann's酮19合成了新型的CD-环偶联配偶体23,以应用于改性的Julia烯化反应,以在A-环和CD-环之间构建一个二烯单元。包括脱保护步骤在内的偶联产率为47-62%。根据C2立体化学分离了非对映异构体后,通过(1)H NMR实验确定了结构(2alpha或2beta),并将其与DeLuca的2-甲基-和2-乙基-1alpha进行了比较,25-二羟基-19-norvitamin D(3)。因此,合成的2alpha-(3-羟丙基)-1alpha,25-d