Improved synthesis of V-PYRRO/NO, a liver-selective nitric oxide prodrug, and analogues

The reported synthesis of O2-vinyl 1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate (V-PYRRO/NO), a hepatoprotective agent, was cumbersome and limited by a poor overall yield of 4% from sodium 1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate (PYRRO/NO). We report an improved synthesis of V-PYRRO/NO in two steps with a significantly higher overall yield of 40% from PYRRO/NO. Using this protocol, a number of structural analogues of V-PYRRO/NO were prepared in good yields.