Diels–Alder Additions, Ene Reactions, and Condensations of 4-(Acylamino)-5-nitrosopyrimidines – Synthesis of 8-Substituted Guanines and of 6-Substituted Pteridinones
作者:Thomas Steinlin、Andrea Vasella
DOI:10.1002/hlca.200890048
日期:2008.3
condensation to provide 8-substituted guanines, or by a Diels–Alder cycloaddition, or an ene reaction, to provide 6-substituted pteridinones, depending on the nature of the acyl group and the reaction conditions. Experimental details are provided for the transformation of (acylamino)-nitrosopyrimidines to 8-substituted guanines, and the scope of the reaction is further demonstrated by transforming the trifluoro
4-(酰基氨基)-5-亚硝基嘧啶通过还原缩合反应生成8-取代的鸟嘌呤,或通过Diels-Alder环加成反应或烯键反应生成6-取代的蝶啶,具体取决于酰基的性质和反应条件。提供了将(酰基氨基)-亚硝基嘧啶转化为8-取代的鸟嘌呤的实验细节,并且通过将三氟乙酰胺25转化为8-(三氟甲基)鸟嘌呤(27)和N,进一步证明了反应的范围。ñ ' -双(nitrosopyrimidinyl) -二甲酰胺29向(- [R ,R) -1,2- -二(胍-8-基)乙烷-1,2-二醇(32)。N-山梨糖基(= N -hexa-2,4-dinoyl)亚硝基嘧啶10的分子内Diels-Alder反应,然后自发消除以裂解初始环加成产物的N,O键,从而获得了蝶啶14或15,其特征在于在C(6)的(Z)-或(E)-3-羟基丙-1-烯基。用Ph 3 P处理10导致C(8) -penta-1,3-dienyl-guanine 18。所述的烯反应Ñ