New Advances in Chemical Research, April 2021.21905-86-2. Chemo-enzymatic cascade processes are invaluable due to their ability to rapidly construct high-value products from available feedstock chemicals in a one-pot relay manner. Introduce a common compound, CAS is 21905-86-2, Name is Cinnoline-4-carboxylic acid, belongs to cinnolinecompound.
EXAMPLE 2 Potassium Cinnoline-4-carboxylate (2) 5.10 g of (1) was added over 30 minutes to a vigorously stirred solution of 2.02 g of potassium carbonate in 25 ml of water, at room temperature. The resulting mixture was stirred for one hour at room temperature, then treated with charcoal, and after filtration the water was evaporated. The residue was azeotropically distilled with toluene and dried at 70 C. under reduced pressure, to give 2, as a light tan powder, m.p.: above 280 C., 21905-86-2
But sometimes, even after several years of basic chemistry education, it is not easy to form a clear picture on how they govern reactivity!, 21905-86-2
Reference：
Patent; E. I. Du Pont de Nemours and Company; US4699651; (1987); A;,
Cinnoline – Wikipedia
Cinnoline – an overview | ScienceDirect Topics