Application
In Japan, potassium 5-nitroorotate monohydrate is mainly used as an ingredient in over-the-counter multivitamin medications and as an additive in soft drinks. In Western Europe, it is not only a component of pharmaceutical vitamins but also widely used in cosmetics as a nutritional cosmetic matrix, which can be absorbed by skin cells, promoting cell metabolism and inhibiting skin aging. In the United States, there is considerable research on potassium 5-nitroorotate monohydrate. A series of orotic acid-based drugs, such as nitroorotate and aminoorotate, have been developed both domestically and internationally. Potassium 5-nitroorotate monohydrate possesses an asymmetric spatial structure and various coordination functional groups, enabling it to form a rich variety of coordination compounds with different metal ions. Potassium 5-nitroorotate monohydrate is a key intermediate in the synthesis of dipyridamole, which is a precursor in the synthesis of persantin and aggrenox.
Synthesis
Maintaining cooling to below 50C, 420 ml (7.68 mol) of concentrated sulfuric acid (H2SO4, about 98%) was added to 169 ml (2.56 mol) of 65% nitric acid (HNO3). Then 200 g of whey acid (1.28 mol; 99.64% purity) was added in batches. The reaction mixture was heated to 50-55C with stirring and kept for 3 hours.
Upon completion of the nitration reaction, the reaction mixture was cooled to ambient temperature (about 10-15C) and then kept cooled to below 30C and decanted into 800 ml of water. When the resulting mixture was cooled to about 0-10C, it was slowly stirred. The precipitated product was filtered and washed with a small amount of cold water and then dried at about 50-60C to obtain 5-nitro orotate.
Weigh KOH, 5-nitro orotate (0.402 g, 2.0 mmol), 1,10-o-phenanthroline (0.360 g, 2.0 mmol) in a round-bottomed flask, add 20 mL of distilled water and 1.0 mL of DMF, and stir for 10 min at room temperature to form a suspension of the mixture, and then transfer it to a stainless steel reactor and react it for 24 h at 100oC, and then naturally cool it to room temperature. Filtered and separated to obtain the bulk crystal 5-nitro orotate potassium salt monohydrate.
