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Two new Erythrina alkaloid glycosides, 1 and 2, and three new diarylpropanoid glycosides 12–14 together with nine known compounds were isolated from the MeOH extracts of the seeds of Erythrina velutina. The structures and absolute configurations of these new compounds were elucidated through comprehensive spectroscopic analyses as well as experimental and calculated ECD data. The inhibitory potency of these compounds against nitric oxide production in LPS-induced RAW 264.7 cells and the cytotoxicity of these compounds against the HeLa and HL-60 human cancer cell lines were also discussed.

Canthin-5,6-dione is a common structure of the fluorescent natural products amarastelline A and nigakinone. Here, we synthesized various derivatives, and studied their fluorescence properties. The effects of substituent groups at the N 3 -, 4- and 10-positions were clarified. N 3 -Substitution influenced the solvent-dependent fluorescent change by modulating tautomerization between canthin-5,6-dione and the 5-hydroxy-6-one form. 10-Substitution also influenced the fluorescence, especially in aqueous solution, in combination with N 3 -substitution. Among the synthesized compounds, 5 showed an ‘OFF-ON-OFF’-type fluorescence change with increase of pH, and therefore served as a novel fluorescent sensor for a specific range of pH. Our findings suggest that canthin-5,6-dione should be useful as a fluorophore moiety for fluorescent labeling of biomolecules and for development of fluorescent probes and sensors.

A new pimarane-type diterpenoid, sucupiol (1), and nine known furanocassane-type diterpenoids, vouacapane (2), 7β-hydroxyvouacapane (3), 7β-acetoxyvouacapane (4), 6α-hydroxyvouacapane (5), 6α-acetoxyvouacapane (6), sucutinirane F (7), sucutinirane E (8), 6α, 7β-diacetoxyvouacapane (9), and 6α, 7β-diacetoxyvouacapane-14β-al (10), were isolated from the seeds of Bowdichia virgilioides and their structures were elucidated by using 2D NMR data. The isolation of 1 provides evidence to support the presence of intermediate A in the course of biosynthesis of furanocassane-type diterpenoids.

Four new eremophilane type sesquiterpenoids, a new bakkane type sesquiterpenoid, and a new secoeremophilane type sesquiterpenoid were isolated from Ligularia brassicoides Hand.-Mass. (Asteraceae) collected in China, and were an epoxy lactone derived from 6-acyloxyeuryopsin 1, 6-acyloxy-9oxoeuryopsin 2, 6-acyloxy-9-oxofuranoeremophilane 3, 6-acyloxyeuryopsin 4, 6-acyloxy bakkane type epoxy lactone 5, and secovirgaurenol 6-O-(2'-hydroxymethyl)acrylate (6), respectively. All but one had a 2'-hydroxymethylacryloyloxy group at C-6. This is the first study to describe the chemical constituents of this species. (C) 2014 Elsevier Ltd. All rights reserved.

Twelve new furanocassane diterpenoids, sucupiranins A–L (1–12), and three known compounds (13–15) were isolated from the seeds of Bowdichia virgilioides. The structures of the compounds were elucidated via 1H and 13C NMR analysis, including 2D NMR (1H–1H COSY, HSQC, HMBC, and NOESY); HRMS data; and X-ray crystallographic analysis. The absolute configurations were defined using their electronic circular dichroism (ECD) spectra by applying the exciton chirality method to the bis-p-bromobenzoate of compound 13. Sucupiranin J (10) inhibited lipopolysaccharide-induced nitric oxide production (IC50 30.6 μM), whereas sucupiranins J (10), K (11), and 13 exhibited weak antimalarial activity against Plasmodium falciparum K1 with IC50 values of 32.2, 23.5, and 22.9 μM and selectivity indices of 4.3, 1.9, and >12.0 (MRC-5/K1), respectively.

Five new 12-oxygenated eremophilane sesquiterpenoids bearing a B-ring enone system were isolated from Ligularia lingiana S.W. Liu (Asteraceae) collected in China. Compound 5 was a Diels-Alder adduct of 3 alpha-angeloyloxy-7 beta H-8-oxoeremophila-9,11(13)-dien-12-al and the monoterpene, ocimene. Compound I showed cytotoxic activities against HeLa, HL60, Jurkat, and NIH-3T3 cells at IC50 0.0407, 0.440, 0.313, and 3.48 mu M, respectively. (C) 2014 Elsevier Ltd. All rights reserved.

Kiusianins A-D (1-4) were isolated from the leaves of a Japanese endemic plant, Tilia kiusiana, together with 14 known compounds. The structures of a new lanostane-type triterpenoid 1 and three new cholestane-type sterols 2-4 were elucidated by spectroscopic methods, including two dimensional (2D) NMR. All the compounds isolated were evaluated for their cytotoxicity against two human cancer cell lines, HeLa and HL-60.

Five new furanocassane-type diterpenoids, sucupiranins M–Q (1–5) were isolated from the seeds of Bowdichia virgilioides. Their structures and stereo chemistries were elucidated on the basis of spectroscopic analyses including HRESIMS, 2D NMR (1H-1H COSY, HSQC, HMBC, and NOESY), and ECD spectra.

Four new compounds, rearranged noreremophilan-8,6-olide, rearranged dinoreremophilanone, epoxy gamma-lactone, and 2 alpha-hydroxyermophil-11-en-9-one, along with eremophilenolides related to ligularol and other known terpenoids, were isolated from Ligularia virgaurea (ligularol type) collected from the northern Sichuan Province of China. Three of the new compounds had degraded and unique structures. The absolute configuration of 2 alpha-hydroxyermophil-11-en-9-one was determined on the basis of density functional theory calculation. The back octant rule cannot be applied to this compound because of the contribution of the hydroxy group to the front octant. (C) 2013 Elsevier Ltd. All rights reserved.

Two new Erythrinan alkaloids, cristanines A and B (1, 2), were isolated from the bark of Erythrina crista-galli L. together with nine known Erythrinan alkaloids (3-5, 7-12) and an indole alkaloid (13). The structures of the compounds, cristanines A (1) and B (2), were elucidated by spectroscopic methods. Three of the twelve compounds isolated showed significant inhibitory activity on lipopolysaccharide induced nitric oxide (NO) production.

Four new oxindole alkaloids, paratunamides A-D (1-4), containing a secologanin unit, were isolated from the bark of Cinnamodendron axillare, and their structures and relative configurations were elucidated by spectroscopic data. The absolute configuration at C-7 in 1-4 was assigned as S, S, R, and S, respectively, on the basis of the CD spectra.

Two new flavonolignans, mururins A and B ( 1 and 2), and a new lignan, mururin C ( 3), were isolated from the bark of Brosimum acutifolium Huber together with three known lignans. Their structures were elucidated by spectroscopic means and chemical modifications. They were tested for protein kinase A (PKA) and protein kinase C (PKC) inhibitory activity. Mururin A showed 3 % and 63 % inhibition to PKA and PKC, respectively, at 20 microM. Mururin B showed 58 % and 38 % inhibition, respectively. Mururin C did not have significant activity.

A termolecular condensation reaction of harmane, alkyl halide, and dimethyl oxalate has been developed for the construction of a variety of canthin-5,6-diones. The carbon skeleton of amarastelline A, a fluorescent canthin alkaloid, was synthesized in 99.8% yield by applying this procedure.

From the roots of Ligularia cymbulifera collected in Yunnan Province, China, two new eremophilane-type sesquiterpenoids (1 and 2) together with ten known compounds (3–12) were obtained through the precise chemical component elucidation. The structure determination was mainly carried out with 1D and 2D NMR data.

A new diterpenoid with a rearranged skeleton, prattinin A (1), was isolated along with five known compounds (2–6) from the roots of Salvia prattii. The structure of 1 bearing a methyl group at the C-5 position was established by extensive spectroscopic analyses and the absolute configuration of 1 was elucidated by comparing the calculated and experimental electronic circular dichroism (ECD) spectra. Compounds 1, 3, 4, and 5 exhibited moderate or weak cytotoxicity against HL-60 and HeLa cell lines.

A novel compound, named salviskinone A (1), was isolated from Salvia przewarskii. The compound has a rearranged carbon skeleton with a methyl unit at C-5 from abietane-type diterpene. Its structure and relative stereochemistry were elucidated by detailed spectroscopic analysis, including HREIMS and 2DNMR (COSY, HSQC, HMBC, and NOESY) spectra. (C) 2011 Elsevier Ltd. All rights reserved.

Three new labdane diterpenoids, pacovatinins A-C (1-3), were isolated from seeds of the Brazilian medicinal plant Renealmia exaltata ("Pacová-catinga"), and their structures including absolute configurations were elucidated by spectroscopic data and a modified Mosher method.

Four new nitrogen-containing clerodane diterpenoids, echinophyllins C-F (1-4), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus ("Chapéu-de-couro"), and their structures and relative stereochemistry were elucidated from their spectroscopic data. Compounds 1-4 possess an alpha,beta-unsaturated gamma-lactam ring consisting of a clerodane diterpene unit and an amine moiety.

Two novel nitrogen-containing clerodane diterpenoids, echinophyllins A (1) and B (2), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus (‘Chapeu-de-couro’), and their structures and relative stereochemistry were elucidated by spectroscopic data. Echinophyllins A (1) and B (2) possess a unique α,β-unsaturated γ-lactam ring consisting of a clerodane diterpene and a tyramine unit or N-feruloyl putrescine unit, respectively.

One new ent-neosecurinane-type alkaloid, secu’amamine E (1), and two novel alkaloids consisting of a ent-neosecurinane and a piperidine unit, secu’amamine F (2), and secu’amamine G (3), were isolated from Securinega suffruticosa var. amamiensis. Their structures and stereochemistry were elucidated on the basis of spectroscopic analyses.

A selective potent anti-Helicobacter pylori isoflavone was isolated from a Brazilian Medicinal Plant, Myroxylon peruiferum. The isolation bioassay-guided and the characterization of an active anti-H. pylori constituent was performed using the methanol extract of plant of minute amount. The active compound was identified as cabreuvin (1), an isoflavone derivative. The structure-activity relationships of several related compounds were also investigated.

A novel indolizidine alkaloid, secu'amamine A (1), was isolated from the leaves and twigs of the medicinal plant, Securinega suffruticosa var. amamiensis together with securinine (2). The structure and relative stereochemistry of 1 was elucidated by spectroscopic data and its absolute configuration was assigned on the basis of the OMe-madelate method.

An extremely potent antitumor neo -clerodane diterpene was isolated from the oleoresin of the Brazilian medicinal plant, Copaifera langsdorfii Desfon. This compound was identified as (-)-kolavenol 1 . The antitumor effect of 1 against IMC carcinomas as determined from the increase in lifespan (I.L.S.) in mice was twice that of 5-FU. The structure elucidation and the antitumor activity of the other related compounds 2 ∼ 6 in this oleoresin were also described.

A new rotenoid, derrisin (1), together with 10 known rotenoids (2-11) were isolated from the roots of Derris malaccensis Plain. The structure of 1 was elucidated by spectroscopic analysis. Nine of the isolated rotenoids (3-11) showed antibacterial activity against Helicobacter pylori.

Four new Erythrinan alkaloids (1—4) were isolated from the seeds of Erythrina velutina. The structures of these new compounds 1—4 were elucidated by spectroscopic methods including 2D-NMR. Three of four were found to be novel sulfated Erythrinan alkaloids.

Brartemicin (1), a new trehalose-derived metabolite, was isolated from the culture broth of the actinomycete of the genus Nonomuraea. Its structure and absolute configuration were determined by spectroscopic analyses. The new compound inhibited the invasion of murine colon carcinoma 26-L5 cells with an IC(50) value of 0.39 microM in a concentration-dependent manner without showing cytotoxic effects.

A new Erythrinan alkaloid (1), erythodine N-oxide, was isolated from the seeds of Erythrina velutina together with seven known Erythrinan alkaloids (2-7, 9) and an indole alkaloid (8). The structure of new compound (1) was elucidated by spectroscopic methods. Six of the nine compounds showed enhanced activity when combined with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Erysotrine (4) did not show cytotoxic activity by itself, but exhibited significant cytotoxicity when combined with TRAIL.

An indole alkaloid (hypaphorine (1)) was isolated from Brazilian medicinal plant, Erythrina velutina (Leguminosae). This compound was investigated for sleep promoting effects in mice, and the results showed that it significantly increased non-rapid eye movement (NREM) sleep time during the first hour after its administration. The NREM sleep time was enhanced by 33% in the experimental mice when compared to that of the controls. This study therefore confirmed its sleep promoting property.

Three new Securinega alkaloids, secu'amamines B-D ( 1- 3), were isolated from the wood of the Japanese medicinal plant Securinega suffruticosa var. amamiensis, together with five known analogues ( 4, 6- 9). The structures 1- 3 were elucidated by spectroscopic methods including 2D NMR, and all eight compounds were evaluated for cytotoxicity against two cancer cell lines.

A new clerodane diterpenoid (6) with a caged hemiacetal ring has been isolated as a minor constituent from Portulaca grandiflora and its structure elucidated by extensive spectral studies. The compound might be of significance in the biosynthesis and in the chemosystematics of constituents of the genus Portulaca. The structural features of 6 provide important clues for the proposal of a chemically reasonable scheme for the biosynthesis of portulal (1).

Two new labdane diterpenoids, 15beta-methoxyfaciculatin (1) and 15alpha-methoxyfaciculatin B (2), together with the previously known methoxynepetaefolin (3), were isolated from a methanol extract of the dried aerial parts of a Brazilian medicinal plant, Hyptis faciculata. Their structures were elucidated by analysis of spectroscopic data. Plausible biogenetic correlation between faciculatins and nepetaefolin is briefly discussed.

Four new flavonoids, brosimacutins J-M (1 - 4), were isolated from the bark of Brosimum acutifolium Huber together with a known flavan, brosimine A (5). The structures of compounds 1-4 were elucidated by spectroscopic means. 27 constituents of this plant including compounds 1-5 were evaluated for their cytotoxic activity against murine leukemia P388 cells. Although no compounds tested had any reversal effect on vincristine resistance, brocimacutins J-M (1-4) were cytotoxic to vincristine-resistant P388 cells (IC50 4.4 - 19 microg/mL).

Four new triterpenoids with various skeletons, maytefolins A−C (1−3) and uvaol-3-caffeate (4), were isolated from the leaves of a Brazilian medicinal plant, Maytenus ilicifolia, together with five known triterpenoids. Of these triterpenoids only erythrodiol exhibited significant cytotoxicity against KB/S, KB/VJ300, and KU 19-20 cells.

Five new monoterpene indole alkaloids, naucleamides A-E (1-5), were isolated from the bark and wood of Nauclea latifolia, and the structures and relative stereochemistry were elucidated from the spectroscopic data. Naucleamide E (5) is a unique monoterpene indole alkaloid possessing a pentacyclic ring system with an amino acetal bridge.

Nine new flavonoids, brosimacutins A-I (1-9), and four known flavonoids were isolated from the bark of Brosimum acutifolium, a Brazilian folk medicine ("Murure"). Their structures were elucidated by spectroscopic methods, including 2D NMR. Brosimacutins A-I possess differentially functionalized isoprene units at C-8.

Two new diarylheptanoids, renealtins A (1) and B (2), have been isolated from the seeds of the Brazilian medicinal plant Renealmia exaltata ("Pacova-catinga", Zingiberaceae), and their structures were elucidated by spectroscopic data. Renealtins A (1) and B (2) are the first example of naturally occurring diarylheptanoids containing a tetrahydrofuran ring.

Two new cembrane diterpenoids with an eight-membered lactone ring, echinodolides A (1) and B (2), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus (“Chapeu-de-couro”), and the structures and relative stereochemistry were elucidated from their spectroscopic data.

A new seco-labdane-type diterpenoid, chapecoderin A (1), and two new rearranged labdane-type diterpenoids, chapecoderins B (2) and C (3), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus ("Chapeu-de-couro"), and their structures and relative stereochemistry were elucidated by spectroscopic data. Chapecoderins A-C (1-3) possess in common an alpha,beta-unsaturated gamma-lactone ring in the side chain.

Fifteen Isodon diterpenoids (1–15) were evaluated for their cytotoxic activity against HeLa and HL-60 human cancer cell lines, and against murine vincristine (VCR)-resistant P388 cells. Kamebanin (14) showed efficient cytotoxic activity against HeLa and HL-60 cells. In addition, although dihydroenmein (2) and trichorabdal B (7) were inactive against several tested cell types, they were found to have cytotoxic-enhancing activity of VCR against VCR-resistant P388 cells.

Two new clerodane-type diterpenes, porwenins A (1) and B (2), were isolated from Portulaca okinawensis, and the structures were elucidated by spectroscopic data.

Two labdane-type diterpenes 4 and 5 isolated from the Brazilian medicinal plant Mimosa hostilis were confirmed to have absolute configurations in enantiomeric relation to each other by X-ray crystallographic analysis of p-bromophenyl carbamate derivative 5a and comparison between 4a and 5b, readily available from 5a.

In the survey of the minor diterpenoid constituents of Portulaca grandiflora Hook, four new compounds, portulic lactone (4), 3-hydroxyportulol ether (5), 5-hydroxyportulal (6), and 5-hydroxyportulic acid (7), were isolated and their structures, all of which have skeletons related to portulal (1), were elucidated on the basis of spectral evidence and chemical correlations.