Synthesis, Anti‐inflammatory, and Arginase Inhibitory Activity of Piceatannol and Its Analogs

The present study describes the synthesis of piceatannol (2) and its analogs (3–8) using Wittig‐Horner reaction, Colvin rearrangement, and Sonogashira reaction as key steps and also evaluation of their inhibitory potency on the production of inflammatory mediator nitric oxide (NO) in lipopolysaccharide (LPS)‐induced RAW‐264.7 macrophages. Three compounds 7 (90.1%), 8 (60.8%), and 6 (55.2%) were found to potently inhibit NO production induced by LPS without affecting the viability of RAW‐264.7 cells. In addition, their Arginase I and II inhibition activity was also evaluated. In this study, three compounds, i.e., compounds 2–4 were showed good inhibition activity to both arginase I and II. Of the synthesized compounds, compound 2 exhibited maximum inhibitory activity of 28% (arginase I) and 26% (arginase II) at 10 μM concentration followed by compounds 3 and 4 of 20 and 22% to arginase I, 22 and 23% to arginase II, respectively.