Synthesis and interconversion of 6‐aroyl‐4‐oxohexanoie acids and 5‐aryl‐2‐furanpropionic acids. Antiinflammatory agents

A series of 6‐aroyl‐4‐oxohexanoic acids (2) was prepared for intermediate use by acid‐catalyzed solvolysis of substituted 3‐(2‐furyl)acrylophenones (1). This reaction occasionally gave 5‐aryl‐2‐furanpropionic acids (3) instead of, or in addition to, the desired diketones (2). Equilibrium between 2 and 3 was observed in the case where Ar is m‐nitrophenyl. A rationalization for the formation of 3 is offered, and published reports with which our results differ are discussed. Diketones (2) were cyclized to furans (3) and antiinflammatory screening data are reported for the latter.