We found some errors in our previous published paper [1]. The structure of simplexin Q was found to be the same as klysimplexin C, previously published in Tetrahedron 2009, 65, 7016–7022 [2]. Also, simplexin S and a known compound cladieunicellin G, reported in Chem. Pharm. Bull. 2012, 60, 160–163 [3], have the same structure (see Figure 1). We apologize for any inconvenience caused to the readers by these errors.