Iridoid glucosides from Viburnum ayavacense

Nine new iridoid glucosides, all characterized by a beta-D-glucopyranosyl moiety linked to the C-ll oxymethylene and either a 3-methylbutyroyl (isovaleroyl) or a 2-methylbutyroyl group at position 1, have been isolated from leaves and branches of Viburnum ayavacense, together with three related known compounds. The nine new structures (namely 7,10,2',3' tetra-acetylsuspensolide F, 7,10,2',3' tetra-acetylisosuspensolide F, 7,10,2',6' tetra-acetylisosuspensolide F, 2',3' diacetylvalerosidate, 2',3' diacetylisovalerosidate, isoviburtinoside II, isoviburtinoside III, isosuspensolide E and isosuspensolide Fl have been elucidated by spectroscopic means. (C) 1997 Elsevier Science Ltd.