Stereoselective synthesis of novel pyrazole derivatives using tert-butansulfonamide as a chiral auxiliary
作者:Chang Min Park、Dong Ju Jeon
DOI:10.1039/c2ob06495b
日期:——
preparation of chiral toluenesulfinyl imine by the condensation of (R)- and (S)-tert-butanesulfinamide with an aldehyde. Next, a corresponding chiral amine synthesis by a stereoselective addition reaction of 4-picolyl lithium to the chiral toluenesulfinyl imine is performed, followed by desulfination. The preparation of the cis-type enaminone from the addition of the enaminone to the corresponding chiral amine
我们的研究计划开发了一种新型手性吡唑衍生物,作为一种有效的PDE4抑制剂,可用于治疗抗炎疾病,例如哮喘和慢性阻塞性肺疾病。公开了通过新颖的方法不对称地合成带有吡唑部分的抑制剂的不对称合成,包括直接与手性中心键合的氮。合成序列的关键步骤始于通过(R)-和(S)-叔丁亚磺酰胺与醛的缩合制备手性甲苯亚磺酰基亚胺。接下来,通过4-吡啶甲基锂与手性甲苯亚磺酰基亚胺的立体选择性加成反应进行相应的手性胺合成,然后进行脱硫。的准备然后完成了将烯胺酮加入相应的手性胺中的顺式烯胺酮,并通过烯胺酮的胺化和随后的脱氢环化作用进一步转化为吡唑衍生物。共完成8个步骤,以产生5.5%的产率(100%ee)。