Two New Ballonigrin-type Diterpenoids from the Roots of Ballota limbata

Two new ballonigrin type lactone diterpenoids, named ballonigrin lactone A and B, have been isolated from the roots of Ballota limbata. Structure elucidation of the isolated compounds was based on spectroscopic {IR, 1H- and 13C-NMR, and 2D-NMR (HMQC, HMBC, COSY and NOESY} and EI-MS data.