Recently, aspernigrin A (1a), which had previously been described by us from a sponge-derived Aspergillus niger, was reisolated from an endophytic Cladosporium herbarum obtained from the inner tissues of Cynodon dactylon (Ye, Y. H.; Zhu, H. L.; Song, Y. C.; Liu, J. Y.; Tan, R. X. J. Nat. Prod. 2005, 68, 1106-1108). On the basis of X-ray crystallographic analysis, the authors revised the 2-pyridone substructure initially proposed for aspernigrin A (1b) to a 4-pyridone (1a), also reassigning 13C NMR signals observed for C-4 (δ 178.1), C-6 (δ 151.2), and C-14 (δ 165.9). Signals observed at δ 177.6, 151.0, and 165.5 were originally assigned by us as C-14, C-4, and C-6, respectively. Due to this misinterpretation of the 13C NMR data, a 4J correlation observed in the HMBC spectrum from H-5 to C-14 was consequently misinterpreted to be a 2J correlation from H-5 to C-6, leading to the wrong structure 1b, which, before this background, was erroneously explained by 2J and 3J correlations. On the basis of the X-ray crystal structure published for 1a in conjunction with the nearly identical NMR data observed for the 4-pyridone moiety, the planar structure of 2 should likewise be revised to a 4-pyridone (2). Consequently, in the 13C NMR spectrum three downfield signals should be exchanged (δ 176.1, C-4; δ 164.5, C-14; δ 151.7, C-6), while in the HMBC spectrum, one of the correlations listed for H-5 should read C-14 (instead of C-4). Since in the original publication three groups represented by three corresponding authors contributed to different main aspects well separated from each other, i.e., W. E. G. Müller (biological testing), G. Bringmann (assignment of absolute configuration), and R. Ebel (isolation and elucidation of planar structure), the last author takes full responsibility for the structure revision for aspernigrin A (1a) and B (2).