Comparative evaluation of a Pictet–Spengler protocol in microwave-assisted conversions of tryptamine with aryl- and carboxyaryl aldehydes: role of ring strain in cyclocondensation of the primarily formed carboxyaryl-substituted β-carbolines
2. Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Arany János Str. 11, 400028, Cluj-Napoca, Romania 1. Institute of Chemistry, Eotvos Lorand University, P.O. Box 32, 1518, Budapest 112, Hungary