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Phytochemical investigation on the nonpolar extracts of P. acidus leaves afforded three new cleistanthane diterpenoids, named phyllanacidins A–C (1–3), in addition to three known ones (4–6). Among them, compounds 2 and 3 represent the first examples of 17-nor cleistanthane diterpenoids. Their structures including absolute configurations were elucidated on the basis of extensive spectroscopic data and single crystal X-ray diffraction analysis. All the isolated cleistanthane diterpenoids were evaluated for their cytotoxic activities against five human cancer cell lines. Compounds 4–6 exhibited moderate cytotoxicity with IC50 values ranging from 16.11 to 30.82 μM.

Six diterpenoids including three ent-kauranes (1-2, 4) and three cleistanthanes (3, 5-6) were isolated from the roots and stems of Phyllanthus acidus (L.) Skeels. Of them, (16S)-ent-16,17,18-tri-hydroxy-19-nor-kaur-4-en-3-one (1), phyllanthone A (2), and 6-hydroxycleistanthol (3) are new compounds, while the ent-kaurane diterpenoids were reported from the titled plant for the first time. Their structures were elucidated on the basis of the extensive spectroscopic analyses. Compounds 2 and 4-6 displayed cytotoxic potential with IC

An elaborated phytochemical study on the fresh fruits of Terminalia chebula var. tomentella (Combretaceae) led to the isolation of five new lignans, including three tetrahydrofuran (1–3) and two furofuran (4 and 5) derivatives, namely termitomenins A-E (1–5), along with 10 known ones. All of them were obtained from the titled plant for the first time. Their structures were determined by extensive spectroscopic analysis, including 1D/2D NMR, MS, UV, IR, electronic circular dichroism (ECD), time-dependent density functional theory (TDDFT) calculation of ECD spectra, and single crystal X-ray diffraction in case of 3. Compounds 1–15 exhibited certain anti-inflammatory activities. Interestingly, compounds 6 (IC50 = 18.17 ± 0.57 μM) and 7 (IC50 = 13.66 ± 0.38 μM) which contain an aldehyde group displayed stronger NO inhibitory activity than the positive control L-NMMA (IC50 = 42.34 ± 0.66 μM).

Four new cleistanthane diterpenoids, phyllaciduloids A–D (1–4), were isolated from the roots and stems of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their structures were elucidated on the basis of extensive spectroscopic analysis. Phyllaciduloids B–D (2–4) present in their structures with ether bond between C-7 and C-16, which were rarely reported. All the isolates were evaluated for their cytotoxic activities against five human cancer cell lines.

Nine new minor dehydrogenated and cleavaged dammarane-type triterpenoid saponins, namely notoginsenosides ST6-ST14 (1-9) were isolated from the steamed roots of Panax notoginseng, together with 14 known ones. Among them, 5-7 and 21-22 were protopanaxadiol type and the left 18 compounds, including 1-4, 8-20, and 23 were protopanaxatriol type saponins. Their structures were identified by extensive analysis of MS, 1D and 2D NMR spectra, and acidic hydrolysis. Resulted from the side chain cleavage, the new saponins 1 and 2 featured in a ketone group at C-25, and 3-5 had an aldehyde unit at C-23. The known saponins 12,16 and 18 displayed the enhancing potential of neurite outgrowth of NGF-mediated PC12 cells at a concentration of 10 mu M, while 20 exhibited acetyl cholinesterase inhibitory activity, with IC50 value of 13.97 mu M. (C) 2015 Elsevier B.V. All rights reserved.