New diterpenoid glucoside and flavonoids from Plectranthus scutellarioides (L.) R. Br.

Three new compounds, diterpenoid glucoside (13S, 15S)-6 beta, 7 alpha, 12 alpha-trihydroxy-13 beta, 16-cyclo-8-abietene11,14- dione 7-O-beta-D-glucoside 1, flavonoids apigenin 7-O-(3''-O-acetyl)-beta-D-glucuronide 2 and apigenin 5-O( 3''-O-acetyl)-beta-D-glucuronide 3, together with known compounds caffeic acid 4, luteolin 5-O-beta-D-glucoside 5 and rosmarinic acid 6 were isolated from the aerial parts of Plectranthus scutellarioides (L.) R. Br. The structures of the new compounds were elucidated by spectroscopic and mass-spectrometric analyses, including 1D-and 2D-NMR. Compound 1 inhibited hyaluronidase by 25% at the concentration of 200 mu M, compounds 2 and 3 showed inhibitory activity on butyrylcholinesterase better than standard galanthamine at the concentration of 100 mu M, and compound 6 is a potent antioxidant with an ORAC value of 2.15 +/- 0.12. (c) 2018 SAAB. Published by Elsevier B. V. All rights reserved.