Synthesis of Metabolites and Related Compounds of 3-Isobutyryl-2-isopropylpyrazolo (1,5-a) pyridine (Ibudilast). I. Metabolites of Alkyl Side Chains.
作者:Katsuya AWANO、Seigo SUZUE
DOI:10.1248/cpb.40.631
日期:——
3-Isobutyryl-2-isopropylpyrazolo[1, 5-α]pyridine (ibudilast) has a large number of metabolites. In order to unequivocally establish the true identity of these metabolites, we prepared a series of authentic reference compounds, namely novel pyrazolo[1, 5-α]pyridine derivatives with mono- and dihydroxylated alkyl side chains and carboxylated alkyl side chains. These results lead to the conclusion that reactions at the 3-position of pyrazolo[1, 5-α]pyridine are governed by the electron-donating effect and the weak basicity of bridge-head nitrogen. On the basis of these results we were able to establish a method of functional group introduction to the alkyl side chains of pyrazolo[1, 5-α]pyridine.
3-异丁酰-2-异丙基吡唑并[1, 5-α]吡啶(ibudilast)具有大量的代谢物。为了明确这些代谢物的真实身份,我们准备了一系列正品参考化合物,即具有单羟基和双羟基烷基侧链以及羧基烷基侧链的新型吡唑并[1, 5-α]吡啶衍生物。这些结果得出结论,吡唑并[1, 5-α]吡啶在3位的反应受电子供给效应和桥头氮的弱碱性影响。基于这些结果,我们能够建立一种在吡唑并[1, 5-α]吡啶的烷基侧链中引入功能团的方法。