Improved Synthesis of Indirubin Derivatives by Sequential Build-Up of the Indoxyl Unit: First Preparation of Fluorescent Indirubins
作者:Herbert M. Riepl、Corinna Urmann
DOI:10.1002/hlca.201200042
日期:2012.8
synthesis of its derivatives relies on the combination of isatins and 2,3‐dihydro‐1H‐indol‐3‐one (‘indoxyl’) derivatives and usually yields indigo as well as other by‐products. Inspection of the hydrolysis of the long‐known condensation products of 2‐thioxothiazolidin‐4‐one with isatins gave useful hints for an improved synthesis of indirubins: this reaction does not yield quinoline derivatives but 2‐(2,