ChemInform Abstract: Arylidene Pyruvic Acids Motif in the Synthesis of New 2H, 5H‐Chromeno[4′, 3′:4, 5]thiopyrano[2, 3‐d]thiazoles via Tandem Hetero‐Diels—Alder‐Hemiacetal Reaction. Issue 5 (January 2016)