Efficient microwave‐assisted synthesis of ellipticine through <i>N</i>‐(1,4‐dimethyl‐9<i>H</i>‐carbazol‐3‐ylmethyl)‐<i>N</i>‐ tosylaminoacetaldehyde diethyl acetal

Abstract

Abstract magnified image The long‐lasting problematic low yield in the D‐ring cyclization of ellipticine ( 1a ) was dramatically improved through N ‐(1,4‐dimethylcarbazol‐3‐ylmethyl)‐ N ‐tosylaminoacetaldehyde diethyl acetal with microwave irradiation. The overall yield of 1a starting from indole was significantly increased by 25‐fold. This new approach is superior to reported methods in yields and, reaction time, and it provides efficient access to a broad spectrum of ellipticine derivatives. J. Heterocyclic Chem., (2010).