A Convenient Preparation of 2-Aroyl-3,3-bis(alkylsulfanyl)acrylaldehydes and Their Application in the Synthesis of 5-Aroyl-2-oxo-1,2-dihydro-2-pyridinecarbonitriles - Anabha, Engoor R; Asokan, Chittoorthekkathil V (Synthesis, 2006)