e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
Synthesis of some new biologically active 1, 3, 4-oxadiazolyl nitroindoles and a modified Fischer indole synthesis of ethyl nitro indole-2-carboxylates
An efficient and modified synthesis of ethyl-4-nitro/5-nitro/6-nitro and 7-nitroindole-2- carboxylates is described. Carbohydrazides of corresponding ethyl nitroindole-2- carboxylates underwent smooth one-step transformation to 1, 3, 4-oxadiazolyl nitroindoles (4a–l) on reaction with aromatic carboxylic acids in the presence of phosphorus oxychloride. An alternate method to synthesize 1, 3, 4-oxadiazolyl nitroindoles is also described. ...