Total synthesis of two naturally occurring polyacetylenic glucosides (−)-bidensyneoside A1 and B, and an analogue of (−)-bidensyneoside C

The total syntheses of two novel polyacetylenic natural products bidensyneoside A1 and B, as well as an analogue of bidensyneoside C are described. These syntheses are based on our recently developed strategy. A new preparation of the required starting material (E)-3-penten-1-yne was developed. The preparation of the analogue of (−)-bidensyneoside C further confirms the side chain configuration of the natural product as (R).