Chemical investigation on the roots of Tinospora sagittata resulted in the isolation of three novel cis-clerodane diterpenoids, tinospinosides D, E, and tinospin E, together with two known compounds, columbin and columbin glucoside, and their structures were determined by extensive spectroscopic analyses, chemical reactions and computer-assisted calculations. The inhibitory activity of the isolated compounds and their chemical derivatives on nitric oxide production in lipopolysaccharide and interferon-γ activited J774.1 macrophage-like cells was also evaluated.