Studies on the Constituents of Syringa Species. I. Isolation and Structures of Iridoids and Secoiridoids from the Leaves of Syringa reticulata (BLUME) HARA

Five new iridoids, named syringopicrogenin-A, -B, -C, syrigopicroside-B and -C, have been isolated together with syringopicroside from the leaves of Syringa reticulata (BLUME) HARA, and their structures have been elucidated on the basis of chemical and spectral evidence. Three secoiridoid glucosides have been also isolated from the same extract, and each of the compounds were identified by direct comparison with authentic samples.