The ammonium salts of many drugs have significantly improved the solubility and, accordingly, bioavailability medicinal substances in human body. 5-(4-Hydroxy-2-oxo-2H-chromen-3-yl)-5H-chromeno[2,3-b]pyridines are potential NPY1R ligands, which attractive for antiobesity treatment. Ammonium 5H-chromeno[2,3-b]pyridines were previously unknown. In this communication, it was found that four-compon...

The enzyme pgalactosidase from a mutant strain of A. niger UV-5 was partially purified using ammonium sulfate and acetone. The saturation range of 60-80% ammonium sulfate was found to yield 60.5% enzyme recovery with 2.4 fold purification. Acetone precipitation at enzyme: acetone ratio of 1 : 1.5 brought about a higher yield i.e. 68% and three-fold purification. The combined procedures of ...