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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

Six new compounds including four prenylated indole alkaloids (1–4) and two lignans (5–6), along with eight known cometabolites (7–14), were isolated from the flower buds of Tussilago farfara. Structures of the new compounds were elucidated by comparison with structurally related known analogues and also by comprehensive spectroscopic analyses. Their absolute configurations were determined by a variety of means including Mosher's method, Marfey's analysis, electronic circular dichroism (ECD) exciton chirality method and ECD calculations. Our bioassays have established that compounds 1 and 2 showed potent α-glucosidase inhibitory activity with IC50 values of 105 ± 4.7 and 35.2 ± 3.2 μM, respectively, while the known 13 and 14 exerted moderate DPPH radical scavenging activity with IC50 values of 45.2 ± 2.9 and 29.2 ± 2.0 μM, respectively.

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.

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 (20R,21S,24S)-21,24-cyclopenta-3β,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

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.

Three new thiophene derivatives, ecliprostins A-C (1-3), have been isolated from the aerial parts of a Compositae medicinal plant Eclipta prostrata, and structures of them have been elucidated by comprehensive spectroscopic analyses. Both ecliprostins A (1) and B (2) feature an acetylenic bithiophenyl backbone and also incorporate an isovalerate moiety, while ecliprostin C (3) is a symmetrical dimer of compound 1 and represents the first example bonded via an ether bridge among the very limited natural dimers. All three compounds show antibacterial activity against Staphylococcus aureus.

Five new lanostane-type triterpenoids, ganoderenses A-E (1-5), two new lanostane nor-triterpenoids, ganoderenses F and G (6 and 7), along with 13 known analogues (8-20) were isolated from the fruiting body of Ganoderma hainanense. Their structures were determined by combined chemical and spectral methods, and the absolute configurations of compounds 1 and 13 were confirmed by single crystal X-ray diffraction. All compounds were evaluated for inhibitory activity against thioredoxin reductase (TrxR), a potential target for cancer chemotherapy with redox balance and antioxidant functions, but were inactive.

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.