6-Aminoindazole is a tetronic acid derivative that has been shown to have an inhibitory effect on the activity of cyclopentyl and ethylene diamine. This drug also increases blood pressure in animals, and is found to be a potent inhibitor of thrombin receptor.
6-Aminoindazole is structurally similar to quinoline derivatives and has been shown to have anticancer activity in human ovarian carcinoma cells. The affinity constants for this compound are higher than those for most other compounds with anti-cancer effects, which may be due to the presence of hydrogen bonds between the nitrogen atoms and the carbonyl group.
General procedure for the synthesis of 6-aminoindazole from 6-nitro-1H-indazole: 6-nitro-1H-indazole (25 g, 0.153 mol, commercially available) was mixed with 10% Pd/C catalyst (2.0 g) in methanol, and the reaction was stirred overnight under hydrogen atmosphere (1 atm). After completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated to afford 6-amino-1H-indazole (18.5 g, 94% yield) as a yellow solid.
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