We have now successfully synthesized (±)-minimiflorin, known as a natural product with H+/K+-ATPase inhibitory activities, via two routes. Considering the structural similarity between H+/K+-ATPase and Na+/K+-ATPase, with 60% sequence homology, we measured the Na+/K+-ATPase inhibitory activities of our synthesized (±)-minimiflorin and found that it has Na+/K+-ATPase inhibitory activities.