The dimeric butenolides glochidiolide and isoglochidiolide, a new glucoside of a nitrogen-containing C(8) dimer, acuminaminoside, and glucosides of C(8) compounds, designated glochidacuminosides A-D, were isolated from the leaves of Glochidion acuminatum. The structures of glochidionolactone and acuminaminoside were determined by X-ray analyses, and those of the remaining C(8) glucosides by NMR spectroscopic analyses, chemical conversion, and a modified Mosher's method.