查看更多>>摘要:? 2022 Elsevier B.V.Six new 2-(2-phenylethyl)chromone dimers (1–6) were isolated from ethyl ether extract of red soil agarwood of Aquilaria crassna from Vietnam by LC-MS-guided fractionation procedure. Their structures were unambiguously elucidated based on HRESIMS, 1D and 2D NMR spectra. The absolute configuration of 2-(2-phenylethyl)chromone dimers was determined by comparison of the experimental and computed ECD spectra. Compound 6 displayed cytotoxicity against the human myeloid leukemia cell line (K562) with an IC50 value of 39.49 μM.
查看更多>>摘要:? 2022 Elsevier B.V.Seven undescribed thermopsine-based alkaloids (1–7), including one undescribed biogenetically related intermediate (7), were isolated from the seeds of Thermopsis lanceolata R. Br. Compound 1 possessed a 6/6–6 tricyclic skeleton, while compounds 2–6 represented three rare dimerization patterns constructed by quinolizidine alkaloids. Their structures were elucidated by comprehensive spectroscopic data analysis as well as ECD calculations. Biologically, compound 6 displayed significant anti-Tomato spotted wilt virus (TSWV) activity compared with the positive control ningnanmycin. Moreover, compound 1 exhibited good insecticidal activity against Aphis fabae with LC50 value of 25.2 mg/L.
查看更多>>摘要:? 2022 Elsevier B.V.Ginsenosides, characterized by triterpenoid, are one of the active components of ginseng. Among them, PPD-type ginsenosides have potent and diverse pharmacological activities, while the effective applications and clinical studies are limited by the poor stability, water solubility and oral bioavailability. In this review, we have attempted to demonstrate the structural-activity relationship of chemical modifications on the dammarane-type skeleton and the C-17 side chain, noting that certain structurally modified derivatives exhibit satisfactory pharmacological activity. This review will provide ideas for the design and synthesis of novel PPD derivatives, and valuable help for the further study of PPD derivatives to make it realize clinical application.
查看更多>>摘要:? 2022Grossheimin 1 is a polyfunctionalized sesquiterpene, featuring, in addition to the exomethylene-γ-lactone group, also an additional exocyclic double bond, a hydroxyl, and a ketone carbonyl. These functional groups have been modified, generally in an orthogonal way, by arylation of the exomethylene, by the introduction of heteroatoms associated to oxygen-, nitrogen- and phosphorous functionalities, and by acylation. A selection of the analogues was investigated for bioactivity, showing that the introduction of a substituent at C-13 is not detrimental, and can modulate potency independently from retention or reduction of the C-11 – C-13 exomethylene double bond and the effect of this maneuver on Michael reactivity. In vivo experiments of 26 samples made it possible to establish that grossheimin 1 and its five new derivatives have a pronounced antitumor activity against alveolar liver cancer, Pliss lymphosarcoma, Walker's carcinosarcoma, sarcoma 45, M-1 sarcoma, P-388 leukemia.
查看更多>>摘要:? 2021Five new α-pyrones, cryptowratones A-E (1–5), and five known congeners (6–10), together with four other known compounds 11–14 were isolated from the twigs of Cryptocarya wrayi. The structures of the new compounds were elucidated on the basis of extensive spectroscopic data analysis and ECD calculations. All α-pyrones except 6 were evaluated for their stimulatory effects on glucose uptake in vitro with CHO-K1/GLUT4 cells. The positive control insulin displayed an approximate 42 ± 0.14% promotion on glucose uptake at 25 μM, compared with the CHO-K1/GLUT4 group. Compounds 1a/2a, 2, 3, and 10 showed a more significant stimulation of glucose uptake than insulin (25 μM) by 36 ± 0.08%, 27 ± 0.12%, 28 ± 0.12%, and 25 ± 0.12% at 1.5 μM, respectively. Immunofluorescence assays indicated the glucose uptake-stimulatory activity of α-pyrones might be correlated with increased GLUT4 translocation.
查看更多>>摘要:? 2022Sixteen guaiane-type sesquiterpenoids were isolated from Stellera chamaejasme L. Among them, chamaejasnoids A-F (1–5) are new compounds. 1 represents the first example of 2,3-seco-guaiane sesquiterpenoid with a 5/6/7 bridged ring system. 2 is a unique 2-nor-guaiane sesquiterpenoid. A plausible biosynthetic pathway for 1 was proposed, involving a Baeyer-Villiger oxidation and a non-enzymatic intramolecular transesterification. 5 exhibited a selective cytotoxicity against HCT8 cell line with an IC50 of 11.82 ± 2.89 μM.