The title compounds 2 are prepared by the cyclization of substituted pyrroles 3 with phosgene in refluxing tetrahydrofuran. In the case of 3a, it is shown that the cyclization can also be achieved after alkylation to give 8.
标题化合物2是通过取代
吡咯3与
光气在回流
四氢呋喃中环化制备的。在3a的情况下,研究表明,环化在烷基化后也可以实现,从而得到8。