1. Department of Food Science and Technology, National Fisheries University, Nagatahonmachi, Shimonoseki 759‐6595, Japan;2. Department of Applied Chemistry, Faculty of Engineering, Kyushu Insitute of Technology, Tobata‐ku, Kitakyushu 804‐8550, Japan;3. Department of Food Science and Technology, Tokyo University of Agriculture, Abashiri, Hokkaido 099‐2493, Japan
Abstract:
The synthetic scheme of 6,6′‐dibromoindirubin ( 2 ) was investigated in detail. The reaction of 6‐fluoro‐3‐acetoxyindole ( 7 ) with isatin ( 8 ) in methanol with Na2CO3 produced 6′‐fluoroindirubin in moderate yields. Its structure determination was mainly undertaken using 1H NMR spectroscopy. On the basis of this result, the synthetic scheme of 2 reported by Cooksey was revised.
