Synfacts, Table of Contents Synfacts 2022; 18(02): 0127DOI: 10.1055/s-0041-1737743 Synthesis of Heterocycles Synthesis of Complex Guanidines by [4+2]-Cycloaddition Indoles with N-Amidinyliminium Ions(Pfizer) Contributor(s): Paul Richardson , Matt DowlingRecommend Article Abstract Buy ArticleKey words Key wordshetero-Diels–Alder reaction - indoles - guanidines - amidinyliminium ions Full Text