3-Hydroxy-2-nitropyridine

Preparation

Synthesis of 3-hydroxy-2-nitropyridine: add 10g of 3-hydroxypyridine, 80ml of ethyl acetate, 4.2g of KNO3 and 21ml of acetic anhydride into a 250mL three-necked flask, and heat at 45°C with magnetic stirring After the reaction is completed, it is cooled to room temperature, filtered with suction, washed with a small amount of ethyl acetate for 1 to 2 times, the filtrate is taken to adjust the pH to neutrality with saturated NaOH solution, and extracted with ethyl acetate for 3 to 4 times. , take the extract and add activated carbon and heat under reflux for 1 hour, cool and filter, take the filtrate, dry with anhydrous magnesium sulfate, filter, concentrate on a rotary evaporator, and dry in a drying oven. 11.9 g of 3-hydroxy-2-nitropyridine was obtained with a yield of 81%.

General Description

3-Hydroxy-2-nitropyridine, also known as 2-nitro-3-hydroxypyridine or 2-nitropyridin-3-ol, is a key precursor in the synthesis of pyridoxazinone derivatives with notable antimicrobial properties. Derived from 3-Hydroxy-2-nitropyridine, the pyridoxazinone series demonstrated significant antibacterial activity, particularly against Gram-negative bacteria such as *Enterococcus faecalis* and *Acinetobacter baumannii*, with MIC values as low as 7.8 μg/mL. Additionally, certain derivatives exhibited potent antifungal effects against *Candida* species. The pyridine ring in these analogs was identified as critical for enhancing antimicrobial efficacy, while 3-Hydroxy-2-nitropyridines maintained low toxicity and favorable drug-like properties. These findings highlight its potential as a scaffold for developing novel antimicrobial agents.