The aim of this article is to study the system piecewise linear difference equations xn+1=|xn|−yn−b and yn+1=xn−|yn|+1 where n≥0. A global behavior for b=4 shows that all solutions become equilibrium point. For a large value |x0| |y0|, we can prove (i) if b=5, then solution becomes point (ii) b≥6, periodic prime period 5.

5H-Chromeno[2,3-b]pyridines are important compounds with industrial, biological, and medicinal properties. In this short note, the multicomponent reaction of salicylaldehyde, malononitrile dimer, 2-phenyl-5-(trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one in dimethyl sulfoxide at ambient temperature was investigated to give 2,4-diamino-5-(5-hydroxy-1-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-5H...