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Chemical fractionation of the ethanolic extract of Eclipta prostrata yielded a series of unreported terpenoid constituents, including a rare 6/6/6/6-fused tetracyclic triterpenoid, a pentacyclic triterpenoid, two pentacyclic triterpenoid saponins, a diterpenoid and a sesquiterpenoid. Structures were assigned to these compounds on the basis of comprehensive spectroscopic analyses, with the absolute configurations of the tetracyclic triterpenoid, the diterpenoid and the sesquiterpenoid being determined via explanation of electronic circular dichroism data. Screening of these isolates in an array of bioassays revealed antibacterial, cytotoxic and α-glucosidase inhibitory activities for selective compounds. Of particular interest, the tetracyclic triterpenoid showed very strong inhibition against α-glucosidase with an IC 50 of 0.82 ± 0.18 μM, being 10 3 -fold as active as the positive control acarbose., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Three new sesquiterpenoids (1 – 3) and two new sesquiterpenoid glucosides (4 & 5), along with 24 known analogues (6 – 29), were obtained from the flowers of Inula japonica. Structures of the new compounds were determined by interpretation of spectroscopic data, and their absolute configurations were established via comparison of experimental with computed ECD curves. All the isolates were tested in an in vitro cytotoxic assay against human A549, MCF-7 and MDA-MB-231 cancer cell lines, and selective ones displayed significant activity close to the positive control adriamycin. The new molecules 1 – 5 were also evaluated for their nitric oxide (NO) release inhibitory effect in murine macrophage RAW264.7 cells, with compound 1 showing comparable activity (IC 50 16.2 ± 0.8 μM) to the positive control dexamethasome. A preliminary mechanistic study of the effect of 8 toward A549 cells revealed that it could arrest cell cycle at G 2 /M phase and induce cell apoptosis in a dose-dependent manner. Unlabelled Image [ABSTRACT FROM AUTHOR]

isolation, structural elucidation, and antioxidative properties of five new cassane diterpenoids, caesalmins I-M, along with 23 known analogues [ABSTRACT FROM AUTHOR]

Under the guidance of MS/MS-based molecular networking, five new clerodane diterpenoid glucosides, tinosinesides R-V (1 – 5), along with 15 known diterpenoids (6–20), were isolated from the stems of Tinospora sinensis. Compound 1 represents the first example of diterpenoid bearing a thio sugar and compound 5 is the first 18,19-dinor-clerodane with cis -fused A/B ring. The structures of the new compounds were elucidated by spectroscopic means, and their absolute configurations were established on the basis of time-dependent density functional theory (TD-DFT) based electronic circular dichroism (ECD) calculation and chemical methods. Selected compounds were evaluated for their immunomodulatory effect and several compounds could enhance the proliferation of B lymphocytes. Preliminary mechanistic studies disclosed that 3 could promote B cell generation and inhibit B cell differentiation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Seven new pentacyclic triterpenoids including six ursane-type, marinoids A–F (1 – 6), and one oleanane-type, marinoid G (7), along with five known analogues (8 – 12), were separated from the roots of Morinda officinalis var. officinalis. Their structures were assigned by spectroscopic means especially analysis of 2D NMR data, with the absolute configurations of 1 and 2 being determined via comparison of their experimental ECD spectra with the computed ones. Selective compounds displayed cytotoxic activity against two human osteosarcoma cell lines and also antibacterial effects against one Gram positive and one Gram negative strains. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Twenty-seven monoterpene indole alkaloids (MIAs) including three new ones were isolated from the plant of Rhazya stricta . Their structures were elucidated by analyses of HRMS and NMR data. Secopleiocarpamine A ( 1 ) represents a novel 2,3- seco pleiocarpamine type MIA possessing a cyano group. A possible biosynthetic pathway for 1 was postulated. All compounds were evaluated for their inhibitory activities against six Candida strains, and the results showed that 2 , 5 , 12 , 21 , 23 , and 27 exhibited moderate inhibitory activities with MIC values ranging from 3.125 to 50 μg/mL. [ABSTRACT FROM AUTHOR]

Chemical fractionation of the EtOH extract of the roots of a traditional Chinese herb, Morinda officinalis , afforded an array of methyl 2-naphthoate derivatives (1 – 9) including four pairs of enantiomers (1 – 4), two pimarane diterpenes and two ursane triterpenoids. Among them, eight compounds (1a / 1b - 3a / 3b , 11 and 13) were reported in the current work for the first time. The structures of the new compounds, including their absolute configurations, were defined by spectroscopic analyses in combination with quantum chemical electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR calculations. All the isolates were evaluated for their inhibitory effect on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine RAW264.7 macrophage cells, and the enantiomers 1a and 3b exhibited moderate activity with IC 50 values of 41.9 and 26.2 μM. Meanwhile, compound 3b also dose-dependently inhibited the secretion of two pro-inflammatory cytokines TNF-α and IL-6 in the same cell model. [Display omitted] • Three pairs of new methyl 2-naphthoate enantiomers were isolated from Morinda officinalis. • One new pimarane diterpenoid and one new unstable ursane triterpenoid were also identified. • Two new enantiomers 1a and 3b showed mild inhibition against the release of NO in RAW264.7 cells. • Compound 3b could dose-dependently block the secretion of pro-inflammatory factors TNF-α and IL-6. [ABSTRACT FROM AUTHOR]

Chemical fractionation of the EtOH extract of a medicinal macro fungus, Inonotus obliquus , afforded an array of lanostane-type triterpenoids (1 − 11) including two new ones (1 and 8). The structures of these compounds were determined on the basis of spectroscopic analyses, single crystal X-ray crystallography of 3 – 6 and biosynthetic considerations. With the confirmatory structural information provided by X-ray diffraction analysis in hand, several previously reported 21,24-cyclolanostanes, such as inonotsutriols A–C and (20 R ,21 S ,24 S)-21,24-cyclopenta-3 β ,21,25-trihydroxylanosta-8-ene, were structurally corrected. In addition, the NMR data of other types of 21,24-cyclo triterpenoids were also re-examined and structural revisions were thus suggested. Compounds 2 , 6 and 8 showed significant cytostatic effects against a panel of tumor cell lines with IC 50 values ranging from 7.80 to 18.5 μM. Further assays established that compound 2 exerted promising in vitro anti-breast cancer potential by inhibiting the proliferation and migration of 4T1 cells. [Display omitted] • Two new lanostane-type triterpenoids were isolated from fungus Inonotus obliquus. • The absolute configurations were characterized by single-crystal X-ray diffraction. • The structures of several previously reported 21,24-cyclolanostanes were corrected. • Selective compounds showed cytotoxicity against lung, breast & gastric tumor cells. • Compound 2 dose-dependently inhibited the proliferation and migration of 4 T1 cells. [ABSTRACT FROM AUTHOR]

Six undescribed low-polarity compounds including three rare 14-methylergostane steroids (1 – 3), one euphane triterpenoid (4) and two octadecanoic acid ethyl esters (5 and 6), along with ten previously reported terpenyl cometabolites (7 – 16), were isolated from the stems of Tinospora sagittata. Their structures were determined by detailed spectroscopic analyses and comparison with structurally related known compounds, and all of them have been reported from T. sagittata for the first time. Compounds 4 – 6 and 16 showed potent in vitro inhibitory activity against the diabetes target α -glucosidase, while compounds 10 and 14 displayed promising antibacterial effect toward Staphylococcus aureus ATCC 25923. [Display omitted] • New 14-methylergostane steroids, euphane triterpenoid and octadecanoid derivatives were separated from Tinospora sagittata. • All the compounds have been reported from Tinospora sagittata for the first time. • Compounds 4 – 6 and 16 showed potent α-glucosidase inhibitory activity. • Compounds 10 and 14 exerted promising antibacterial effect toward Staphylococcus aureus. [ABSTRACT FROM AUTHOR]