Chemical components of noni (Morinda citrifolia L.) root

Morinda citrifolia (Rubiaceae), commonly known as noni, is a plant typically found in the Hawaiian and Tahitian islands. It is believed to be one of the most important plants brought to Hawaii by the first Polynesians. The bark, stem, root, leaf and fruit have been used traditionally as a folk remedy for many diseases including diabetes, hypertension, and cancer. In this research, we reported the constituents of the roots of this plant, which included 3 new naphthoquinone derivatives and one new anhydride. Their structures were identified by the combination of APCI-MS, 1D and 2D-NMR (COSY, TOCSY, ROSEY, HMQC and HMBC).