A Novel and Efficient Approach for the Combinatorial Synthesis of Structurally Diverse Pyrimidines on solid support
作者:Daniel Obrecht、Christine Abrecht、Alfred Grieder、Jos� M. Villalgordo
DOI:10.1002/hlca.19970800106
日期:1997.2.10
We describe a versatile novel approach for the synthesis of 2, 4, 6-trisubstituted pyrimidines on solid support. Thus, polymer-boun J thiouronium salt 2 reacted in high yield in a cyclocondensation reaction with the acetylenic ketones 3 to form, after tert-butyl-ester cleavage, the polymer-bound carboxylic acids 4, which were cleaved by oxidation with 3-chloroperbenzoic acid and pyrrolidine to form
我们描述了一种在固体载体上合成2、4、6-三取代的嘧啶的通用新颖方法。因此,在叔丁基酯裂解后,聚合物-JJ硫脲鎓盐2以高收率在环缩合反应中与乙炔酮3反应,形成聚合物结合的羧酸4,其通过与3-氯过苯甲酸的氧化而裂解。酸和吡咯烷以高产率和纯度形成2-吡咯烷基基嘧啶-4-羧酸6a-c,而无需进一步纯化(方案1)。或者,将酸4a进行Ugi四组分缩合反应,使聚合物结合Ugi产品9a-e的收率很高(方案2)。砜8a与不同亲核试剂的多向裂解反应导致嘧啶-4-羧酰胺10-13的干净形成(方案3)。该策略有效地将固相化学与多组分反应和多方向裂解步骤结合在一起,以平行阵列的形式形成高度多样化的嘧啶。