| The chemical analysis of three Penstemon (Scrophulariaceae) species (Penstemon glaber, Penstemon secundiflorus and Penstemon mucronatus) yielded three new iridoid glycosides. The three new iridoids all contained the rare C-5/C-9 trans ring fusion. Two of those found in P. mucronatus had C-10 in the ;The biosynthesis of iridoids in P. secundiflorus was investigated. Feeding studies revealed that the C-5/C-9 trans fused compound ;The chemical investigation of five Cornus (Cornaceae) species (Cornus nuttallii, Cornus florida, Cornus canadensis, Cornus stolonifera and Cornus peruviana) was carried out. Several known iridoid and other glycosides were isolated. It was determined that there is little variation in iridoid content due to location. |
