Deheiculatins A-L, 20-oxygenated cembranoids from Macaranga deheiculata

Twelve cembranoids, deheiculatins A-L, were isolated from the leaves and twigs of Macaranga deheiculata. Their structures were elucidated on the basis of spectroscopic data. Five of these compounds displayed moderate inhibitory activity against human and/or mouse 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). 20-Oxygenated cembranes are rare.

Diterpenoids and Lignans from Cephalotaxus fortunei

Five new diterpenoids including two Cephalotaxus troponoids (1 and 2), two 17-nor-cephalotane-type diterpenoids (3 and 4), and an abietane-type diterpenoid (5), two new lignans (6 and 7), and a new trisnorneoligan (8) along with eight known compounds were identified from the twigs and leaves of Cephalotaxus fortunei. The structure of 11-hydroxyhainanolidol was revised as 10-hydroxyhainanolidol (9) by X-ray crystallographic data. Compounds 3 and 4 are the first examples of 17-nor-cephalotane-type diterpenoids that are likely the biosynthesis precursors of the co-occurring troponoids (e.g., 1, 2, and 9). Compound 1 exhibited cytotoxic activities against HL-60 and A-549 cells with IC₅₀ values of 0.77 ± 0.05 and 1.129 ± 0.057 μM, respectively.

Nanomolar Antimalarial Agents against Chloroquine-Resistant Plasmodium falciparum from Medicinal Plants and Their Structure-Activity Relationships

Inspired by the discovery of the antimalarial drug artemisinin from a traditional Chinese medicine (TCM), a natural product library of 44 lindenane-type sesquiterpenoids was assessed for activities against the Dd2 chloroquine-resistant strain of the malaria parasite Plasmodium falciparum. These compounds were mainly isolated from plants of the Chloranthus genus, many species of which are named "Sikuaiwa" in TCM and have long been used to treat malaria. The compounds consisted of 41 sesquiterpenoid dimers and three monomers, including the 12 new dimers 1-12 isolated from Chloranthus fortunei. The results showed that 16 dimers exhibited potent antiplasmodial activities (<100 nM); in particular, compounds 1, 14, and 19 exhibited low nanomolar activities with IC₅₀ values ranging from 1 to 7 nM, which is comparable to the potency of artemisinin, and selectivity index values toward mammalian cells greater than 500. A comprehensive structure-activity relationship study indicated that three functional groups are essential and two motifs can be modified.

Euphorbesulins A-P, Structurally Diverse Diterpenoids from Euphorbia esula

Aqueous ethanol extracts of powdered twigs of Euphorbia esula afforded 16 new diterpenoids, named euphorbesulins A-P. These euphorbesulins included presegetane (1-3), jatrophane (4-14), paraliane (15), and isopimarane (16) diterpenoids as well as six known analogues. Compounds 1-3 represent a rare type of presegetane diterpenoid. Their structures were determined by analysis of the spectroscopic data, and the absolute configuration of 1 was established by X-ray crystallography. Diterpenoid 7 showed low nanomolar antimalarial activity, while the remaining compounds showed only moderate or no antimalarial activity.

Cephalotanins A-D, Four Norditerpenoids Represent Three Highly Rigid Carbon Skeletons from Cephalotaxus sinensis

Four polycyclic norditerpenoids, cephalotanins A-D (1-4) representing three unprecedented carbon skeletons with highly rigid ring systems, were isolated from Cephalotaxus sinensis and structurally characterized by a combination of various methods. Compounds 1 and 2 are new skeletal norditerpenoid trilactones, while 3 and 4 are two norditerpenoids featuring different new carbon skeletons. Biosynthetic pathways for 1-4 were proposed by involving diverse and very fascinating chemical events with the coexisting cephalotane troponoids as the precursors. Compound 1 exhibited good NF-κB inhibition with an IC50 value of 4.12±0.61 μΜ.

Eucarobustols A-I, Conjugates of Sesquiterpenoids and Acylphloroglucinols from Eucalyptus robusta

Nine new conjugates of sesquiterpenoids and acylphloroglucinols, named eucarobustols A-I (1-9), as well as 11 known analogues were isolated from the leaves of Eucalyptus robusta. The sesquiterpenoid motifs furnishing the new conjugates included four structural types of aristolane (1 and 2), guaiane (3), eudesmane (4), and aromadendrane (5-9) moieties. Compounds 1 and 2 were found to represent the first examples of conjugates of aristolane and acylphloroglucinol units. In turn, compound 3 features a new coupling model of guaiane and acylphloroglucinol via the C-4-C-7' bond. Compounds 1, 7, and 9 showed inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) with IC50 values of 1.3, 1.8, and 1.6 μM, respectively.

Two new bisamides from the leaves of Aglaia perviridis

Two new bisamides, aglaiamides A (1) and B (2), along with three known ones (3-5), were isolated from the leaves of Aglaia perviridis. Their structures were established on the basis of detailed spectroscopic analyses.

Limonoids and Triterpenoids as 11β-HSD1 Inhibitors from Walsura robusta

Nine new cedrelone-type limonoid derivatives, walsunoids A-I (1-9), and 11 known compounds were isolated from the leaves of Walsura robusta. Walsunoid A (1) is a new degradation product of cedrelone-type limonoids, and walsunoid I (9) is a rare cedrelone-type limonoid amide. Their structures and absolute configurations were determined by spectroscopic data, single-crystal X-ray diffraction, and ECD data analyses. Five compounds showed moderate inhibitory activities against human and/or mouse 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) with IC50 values ranging from 0.69 to 9.9 μM.

Mannolides A-C with an Intact Diterpenoid Skeleton Providing Insights on the Biosynthesis of Antitumor Cephalotaxus Troponoids

Three new diterpenoids, mannolides A-C (1-3), and two new Cephalotaxus troponoids, 4 and 5, were isolated from Cephalotaxus mannii and structurally characterized by spectroscopic data and X-ray crystallography. The discovery of compounds 1-3 featuring a new intact carbon skeleton, proposed as cephalotane, sheds new light on the biogenesis of Cephalotaxus troponoids, a rare class of antitumor C19 norditerpenoids. Antitumor tests showed that the tropone motif is essential for the activity.

Himalensines A and B, Alkaloids from Daphniphyllum himalense

Chemical investigation into the alkaloidal constituents of the Nepalese Daphniphyllum himalense has returned two new compounds, himalensines A (1) and B (2), with unprecedented carbon skeletons. Structures of the two alkaloids have been characterized on the basis of spectroscopic methods, especially via 2D NMR data analysis. Himalensine B (2) showed marginal inhibitory activities against two kinases, PTP1B and IKK-β.

Formosins A-F: Diterpenoids with Anti-microbial Activities from Excoecaria formosana

Three new halimane-type diterpenoids formosins A-C (1-3), and three clerodane-type diterpenoids formosins D-F (4-6), were isolated from the twigs of Excoecaria formosana. Their structures were assigned on the basis of spectroscopic data analysis. Compounds 1 and 4 showed moderate anti-microbial activities against Bacillus subtilis (MIC = 50 and 50 μg/mL, respectively). Compound 6 exhibited moderate anti-microbial activities against two strains of Helicobacter pylori (Hp-SS1 and ATCC 43504) with MIC values of 50 and 50 μg/mL, respectively.

Cipacinoids A-D, Four Limonoids with Spirocyclic Skeletons from Cipadessa cinerascens

Four limonoids, cipacinoids A-D (1-4), with spirocyclic skeletons were isolated from Cipadessa cinerascens. It is particularly notable that compounds 1-3 had a 17S-configuration for the first time in the limonoid family. Their structures with absolute configurations were assigned by spectroscopic data, X-ray crystallography, and CD analysis. Compound 1 showed moderate protein tyrosine phosphatase 1B (PTP1B) inhibition.

New diterpenoids from Sapium discolor

Chemical fractionation of the ethanolic extract generated from the twigs and leaves of Sapium discolor led to the isolation and identification of four new macrocyclic diterpenoids including three members of the rare casbane family, sapidisins A-C (1-3), and an analog of the cembrane class, sapidisin D (4), a new 3,4-seco ent-kaurane diterpenoid (5), and 18 known phenolic compounds. Their structures were elucidated by comprehensive spectroscopic analyses especially 1D NMR (1)H-(1)H couplings and 2D NMR ROESY data. The discovery of 1-4 from S. discolor provides a clue for further study on the biogenetic evolution of the widely existent tigliane-type diterpenoids in the Sapium species.

New alkaloids from Daphniphyllum himalense

A series ofDaphniphyllumalkaloids with selective kinase inhibitory activity were isolated and structurally characterized fromDaphniphyllum himalense.

Flueggether A and Virosinine A, Anti-HIV Alkaloids from Flueggea virosa

Two new alkaloids, flueggether A (1) and virosinine A (2), were isolated from a Chinese medicinal plant, Flueggea virosa. Their structures were assigned via spectroscopic methods with the absolute configurations of 1 and 2 being established by X-ray diffraction analysis and calculated electronic circular dichroism data, respectively. Compound 1 represents the first example with an ether bridge of Securinega alkaloid oligomers, and 2 bears a new heterocyclic backbone. Both alkaloids showed mild in vitro anti-HIV activity.

Clinical and cytogenetic results of a series of amniocentesis cases from Northeast China: a report of 2500 cases

The aims of this study were to demonstrate the clinical and cytogenetic results of amniocentesis (AS) cases in Northeast China, to compare the incidence of different kinds of chromosomal abnormalities, and to study the association between the detection rate of chromosomal abnormalities and different indications for prenatal diagnosis. Cytogenetic analysis was performed on long-term tissue cultures of 2500 second-trimester amniotic fluid samples. The most common indication for genetic AS was abnormal maternal serum-screening test (69.56%), followed by advanced maternal age (15.04%). Chromosomal abnormality was detected in 206 (8.24%) of the 2500 samples. The detection rate of abnormal karyotypes was 62.5% in the group in which one member of the couple was a carrier of a chromosome abnormality; in the group having a positive result from noninvasive prenatal testing, the frequency was 50%. To determine the origin of fetal chromosome abnormal karyotype, 45 fetuses were analyzed. Of these, 20 were found to be de novo abnormalities and 25 were familial. The frequency and proportion of abnormal karyotypes varied substantially across different maternal AS indications. Knowing the origin and type of chromosomal abnormality would help determine termination or continuation of the pregnancy.

Terpenoids and Steroids from Euphorbia hypericifolia

Two new triterpenoids and two new sterols, named euphyperins A-D (1–4), including an oleanane-type triterpenoid (1), a lupane-type nortriterpenoid (2), and two cholestane-type steroids (3 and 4), along with five known compounds (5–9) were isolated from the twigs and leaves of Euphorbia hypericifolia. Euphyperin B (2) represents a rare lupane-type nortriterpenoid, and euphyperin C (3) is a novel 8,14-secocholestane-type steroid. Euphyperin A (1) exhibited moderate PTP1B inhibitory activity with an IC50 = 17.05 ± 1.12 μg/mL.

Terpenoids and Steroids from Euphorbia hypericifolia

Two new triterpenoids and two new sterols, named euphyperins A-D (1-4), including an oleanane-type triterpenoid (1), a lupane-type nortriterpenoid (2), and two cholestane-type steroids (3 and 4), along with five known compounds (5-9) were isolated from the twigs and leaves of Euphorbia hypericifolia. Euphyperin B (2) represents a rare lupane-type nortriterpenoid, and euphyperin C (3) is a novel 8,14-secocholestane-type steroid. Euphyperin A (1) exhibited moderate PTP1B inhibitory activity with an IC50 = 17.05 ± 1.12 μg/mL.