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Picrasamide A (1), a new cinnamamide derivative, together with two new β-carboline alkaloids (2 and 3) and five known β-carboline alkaloids (4–8) were isolated from the stems of Picrasma quassioides (D. Don) Benn. Their structures were elucidated by detailed analyses of UV, IR, HRESIMS, and NMR data. Compound 1 was the first case of cinnamamide derivative from genus Picrasma. The AChE inhibitory activity and the antimicrobial activity of 1–8 were assessed. In addition, preliminary structure-activity relationships of these β-carboline alkaloids on the AChE inhibitory activity and antimicrobial activity were proposed.

A total of six new alkaloids, melodinhenines A-F (1-6), were isolated from Melodinus henryi. Melodinhenines A and B are new eburnan-vindolinine-type bisindole alkaloids and melodinhenines C-F are new quinolinic melodinus alkaloids. Their structures were elucidated through extensive spectroscopic methods including 2D NMR and HRESIMS analyses. The absolute configuration of 1 and 2 was determined using ECD exciton chirality method. To the best of our knowledge, this is the first report on the determination of the absolute configuration of eburnan-vindolinine-type bisindole alkaloid using this method.

Five new labdane diterpenes (1-5), serralabdanes A-E, were isolated from the whole plant of Chloranthus serratus. Their structures were elucidated by spectroscopic methods, and the absolute configuration of the 12,13-diol moiety in serralabdane C (3) was determined by observing the induced circular dichroism (ICD) after addition of dimolybdenum teracetate in DMSO solution. Serralabdanes A-E (1-5) showed inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells.

Two new compounds, a neolignan (1), and a benzofuran derivative (2), along with 6 known compounds (3-8), were isolated from the aerial parts of Leontopodium leontopodioides. The structures of the new compounds were elucidated as (7R,8S)-3,5'-dimethoxy-4',7-epoxy-8,3'-neolignane-5,9,9'-triol (1) and (2R)-12-hydoxy-4-methoxy-tremeton (2) on the basis of their spectroscopic data, respectively. All of the isolates were evaluated for their effects on the inhibition of nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophages and compounds 1 and 8 exhibited inhibitory activity with IC(50) values of 35.80 and 24.41 μM, respectively.

A new coumaronochromone, 6,4'-dihydroxy-7,5' -dimethoxy-coumaronochromone (1), together with eleven known flavonoids (2-12) were isolated from the ethanol extract of the aerial part of Derris elliptica. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 2, 4, 7, 8 and 9 exhibited moderate insecticidal activities against larvae of Aedes albopictus. All compounds showed strong cytotoxic activities against Spodoptera litura (SL) and Trichoplusia ni BTI-Tn-5B1-4 (Hi-5) cells comparison to positive control of rotenone.

A phytochemical study on the ethanolic extract of the stem barks of Uncaria laevigata leads to the isolation and characterization of 18 triterpenoid compounds. Ten of these are new, including one novel heptanortriterpenoid (1), four ursane triterpenes (2–4, 10), and five oleanane triterpenes (5–9). Their structures were established by spectroscopic methods, especially by 2D-NMR and MS analyses. All these isolates were evaluated for their inhibitory effects on α-glucosidase: ursolic acid and 3 showed potent activities with IC50 values of 16 ± 2.2 and 49 ± 3.7 μM, respectively.

Two novel dimeric indole alkaloids were isolated from the leaves and twigs of Psychotria henryi. Their structures were established by chemical and spectroscopic methods. Compound 1 was a novel dimeric tryptamine-related alkaloid that contained an unprecedented decacyclic ring system, and compound 2 featured a pyrido[3,4-b]indole moiety adjacent to a pyrrolidinoindole skeleton. The absolute configurations of compounds 1 and 2 were determined by calculation of electronic circular dichroism (ECD) using density functional theory (DFT).

Two new sesqui-neolignans with novel conjugation way, simonol A (1), featuring a unique motif of a 5,5-dihydro-pyran with a hemiketal carbon, while simonol B (2) possessing two dihydronfuran rings in the same direction, were isolated from the ethanol extract of the fruits of Illicium simonii. Their structures were elucidated by spectroscopic methods including 1D and 2D NMR, HRESIMS, and calculation of electronic circular dichroism (ECD) using density functional theory (DFT). The two isolates were evaluated for their inhibitory activities against the growth of four lines of human cancer cells (NCI-H460, SMMC-7721, MCF-7, BGC-823): 1 showed strong activities comparable to 5-Fluorouracil, and 2 to a less content. In addition, plausible biosynthetic routes for the two compounds were also proposed.

From the flowers of Chrysanthemum indicum, three new germacrane-type sesquiterpene stereoisomers (1β,3α,5β-trihydroxyl-7-isopropenyl-germacren-4(15), 10(14)-diene (1), 1β,3β,5α-trihydroxyl-7-isopropenyl-germacren-4(15), 10(14)-diene (2), 1β,3β,5β-trihydroxyl-7-isopropenyl-germacren-4(15), 10(14)-diene (3)) were isolated, whose structures were elucidated on the basis of extensive spectroscopic analysis. The absolute configuration of compound 1 was determined by a single crystal X-ray diffraction study using a mirror Cu Kα radiation.

Four new sesquiterpenes, chlorajapolides F-I (1-4), along with nine known terpenoids (5-13) were isolated from the aerial part of Chloranthus japonicus. Their structures were elucidated on the basis of spectroscopic analysis, and a lindenane sesquiterpene, named 9-hydroxy-heterogorgiolide, previously isolated from the C. japonicus, was revised as its 8-epimer (1a). Moreover, methanol extract (ME), EtOAc fraction (EF), water fraction (WF), and all isolates (1a, 1-13) were evaluated for their cytotoxicities using two human cancer cell lines.

The methanol (MeOH) extract of the twigs and leaves of Aglaia duperreana was investigated for its molluscicidal activity against Pomacea canaliculata. The extract was found to exhibit significant molluscicidal activity. The ethyl acetate soluble fraction of the extract showed the most potent molluscicidal activity among different solvent fractions. The bioactivity-guided chemical investigation of the ethyl acetate soluble fraction led to a new triterpenoid along with 15 known compounds. Their structures were elucidated by spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance techniques as well as mass spectroscopic analysis. The molluscicidal activities of compounds 2–16 against P. canaliculata were also investigated. Naringenin trimethyl ether showed significant molluscicidal activity with a median lethal concentration (LC50) of 3.9 μg/mL, which was indicated higher potency than the positive control, tea saponin (LC50 = 4.5 μg/mL).

Two new triterpenoids, 2 α -hydroxyurs-12-en-28-oic acid-3 β - trans - isoferulate ( 1 ) and 2 α , 3 α , 24-trihydroxyolean-18-en-28-oic acid ( 2 ), together with three known triterpenoids ( 3 – 5 ) were isolated from the methanol extract of the bark of Eucalyptus exserta . Their structures were determined by spectroscopic means. Compounds 1 , 2, and 5 exhibited molluscicidal activity against Pomacea canaliculata . All isolated compounds showed significant cytotoxic activity against Spodoptera litura (SL) cells.

A novel aporphine alkaloid, magnofficine (1), has been isolated from the root barks of the Chinese medicinal plant Magnolia officinalis, along with seven known compounds. Elucidations of their structures were achieved by spectroscopic methods. Magnofficine is the first example of an adduct of aporphine alkaloid and 4-hydroxyphenethylamino bridged by a methylene.