In this paper is reported an in deep study of the glycosidic fraction of S. alopecuros subsp. divulsa which permitted to widen the knowledge on its iridoid pattern, being constituted also by ajugoside (1), reptoside (6) and 6-O-acetyl-ajugol (7), besides 8-O-acetylharpagide (2), harpagide (3), allobetonicoside (4), 4′-O-galactopyranosyl-teuhircoside (5) which had been already isolated from this species. The phenolic compounds isolated during the study resulted to be chlorogenic acid (8), β-arbutin (9), verbascoside (10) and stachysoside A (11) instead. Except for the reconfirmed verbascoside (10), the other phenolic compounds were recognized for the first time in the studied species. The complete NMR assignment of compound (1) by means of bidimensional techniques is reported and both the chemotaxonomic and pharmacologic relevance of the isolated compounds are discussed.
Key words: Iridoid, Chemotaxonomy, NMR, Chlorogenic acid, β-arbutin, Phenylethanoid glycosides.
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