New ellagitannins from Tiencha and their inhibitory activity against dental plaque

Four new galloyl-oxygen-diphenyl (GOD)-type ellagitannins, brambliins A–D (1–4), were isolated from the leaves of Rubus suavissimus. Their structures were elucidated by extensive spectroscopic analyses and the absolute configurations of 1–4 were determined by chemical and phytochemical evidence. These GOD-type ellagitannins inhibited the formation of dental plaque, which is beneficial for oral hygiene.