Benzoate esters and flavonoids from Desmos pedunculosus

The genus Desmos (Annonaceae) is comprised of about thirty-three species of trees and shrubs found in southern Asia, Indonesia, and northern Australia. The chemistry of many of these species is largely unreported. Phytochemical investigation of a methanol extract of the aerial parts of D. pedunculosus led to the isolation of two flavonoids and eight benzoate ester derivatives. Three of these benzoate esters are new compounds, while two others are known synthetic compounds reported here as natural products for the first time. The compounds were characterized by mass spectrometry and 1D and 2D NMR spectroscopy. Based on a comparison of extracts of D. chinensis and D. pedunculosus from Vietnam, several of the compounds we report may serve as marker compounds to chemically distinguish these similar species.     

Two new saponins from Paronychia capitata

Two new oleanane-type triterpene glycosides, 3˗O˗β˗D˗glucopyranosyl˗28˗O˗[β˗D˗glucopyranosyl˗(1→2)˗β˗D˗xylopyranosyl˗(1→6)˗β˗D˗glucopyranosyl]medicagenic acid (1) and 3˗O˗β˗D˗glucopyranosyl˗28˗O˗[β˗D˗glucopyranosyl˗(1→6)˗β˗D˗glucopyranosyl˗(1→2)˗ β˗D˗xylopyranosyl]oleanolic acid (2), named capitatosides A and B respectively, were isolated from the butanol extract of Paronychia capitata (L.) Lam., along with seven known compounds. The structures of the isolated compounds were established by spectroscopic methods, mainly HRMS, 1D and 2D NMR (¹H, ¹³C, COSY, HSQC, HMBC and NOESY) techniques, whereas those of the known compounds were identified by spectral comparison with reported literature data.     

New sesquiterpenes from the endophyte Microdiplodia sp. TT-12 and their antimicrobial activity

Four new compounds, phomadecalin F (1), 8α-monoacetoxyphomadecalin D (2), 3-epi-phomadecalin D (3), and 13-hydroxylmacrophorin A (4), were isolated from the endophyte, Microdiplodia sp. TT-12 together with two known compounds, phomadecalins C (5) and D (6). The structures of the compounds were elucidated by NMR spectroscopic and mass spectrometric analyses in combination with chemical means. The antibacterial activities of the isolated compounds were evaluated. Compound 4 was weakly active against Raffaelea quercivora.     

Flower scent composition in Dianthus and Saponaria species (Caryophyllaceae) and its relevance for pollination biology and taxonomy

Floral fragrance compounds of seven Dianthus species (D. arenarius, D. armeria, D. barbatus, D. deltoides, D. monspessulanus, D. superbus, and D. sylvestris) and one Saponaria species (S. officinalis) (Caryophyllaceae) were studied using headspace adsorption technique followed by gas chromatography massspectrometry (GC-MS). The number of compounds (fatty acid derivatives, benzenoids, phenyl propanoids, isoprenoids, and nitrogen containing compounds) identified in the floral odors ranged from 18 to 51 but all were dominated by only 1–3 compounds. Most of the compounds identified in this study have been previously reported in floral scents from species of the closely related genus Silene L. However, the phenyl propanoids eugenol, methyleugenol, methylisoeugenol, cis-asarone, and trans-asarone have formerly not been found in Silene. Based on the measurement of Sørensen’s index of similarity (I_s) nonmetric multidimensional scaling (MDS) was used to detect meaningful underlying dimensions and to visualize similarities between the investigated species. The MDS analysis showed three groups of species, (1) the diurnal D. armeria, D. barbatus, and D. deltoides are characterized by the predominance of fatty acid derivatives, (2) the closely related nocturnal D. monspessulanus, and D. superbus by high relative amounts of isoprenoids such as cis-β-ocimene and β-caryophyllene, and (3) the species D. arenarius, D. sylvestris and S. officinalis by a predominance of benzenoids, especially methylbenzoate. The results are discussed in relation to pollination, especially by butterflies, moths, and hawkmoths.     

Phenolic dimers and an indole alkaloid from Campylospermum flavum (Ochnaceae)

From the leaves and stem bark of Campylospermum flavum (Ochnaceae), three compounds, namely 4?-O-methylagathisflavone, flavumchalcone, and flavumindole have been isolated together with 10 known compounds, including three flavonoids, two biflavonoids, two alkaloids, two nitrile glucosides, and glucopyranosyl-β-sistosterol. The structures of these compounds and their relative configurations were established by 1D and 2D NMR experiments. The methanolic crude extracts of leaves and stem bark of C. flavum and compounds displayed a significant cytotoxicity towards Artemia salina larvae.     

Evaluation of analgesic and anti-inflammatory activities and molecular docking analysis of steroidal lactones from Datura stramonium L.

BackgroundDatura stramonium L. is widely used across the world for its therapeutic potential to treat inflammatory disorders. The current work was designed to isolate and identify steroidal lactones from D. stramonium leaves and evaluate their anti-inflammatory and analgesic properties.MethodsSeveral compounds were isolated from D. stramonium leaves and characterized by nuclear magnetic resonance and high-resonance electron spray ionization mass spectrometry techniques. Further, anti-inflammatory properties of these compounds were evaluated by in vitro assays, such as release of NO and pro-inflammatory cytokines by lipopolysaccharide (LPS)-activated J774A.1 macrophages. Using in vivo models, anti-inflammatory and analgesic effects were examined by mouse tail-flick, carrageenan-induced inflammation in rat paw model, vascular permeability in rats, and acetic acid-induced writhing in mice. The docking studies were performed for assessing the binding efficiency of the test compounds with cyclooxygenase-1 (COX-1) and COX-2, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), inducible nitric oxide synthases (iNOS) and nuclear factor-κB (NF-κB).ResultsThree lactones were isolated and confirmed as daturalactone (D1), 12-deoxywithastramonolide (D23), and daturilin (D27). Further, the isolated compounds showed nitric oxide inhibition and pro-inflammatory cytokines released by LPS-activated J774A.1 macrophages. The in vivo results suggest that D1, D23 and D27 (20 mg/kg) were able to reduce the pain and inflammation in various animal models. The docking analysis showed that these three compounds actively bind with COX-1, COX-2, LOX-1, NF-κB, and iNOS, validating the anti-inflammatory effects of the lactones.ConclusionThese findings demonstrate substantial anti-inflammatory and analgesic properties of D. stramonium-derived lactones and their potential as anti-inflammatory agents to treat chronic inflammatory ailments.     

Cytotoxic cycloartanes from the fruits of Caloncoba glauca

Two new cycloartane-type triterpenoids, glaucartanoic acids A (1) and B (2), together with five known compounds were isolated from the fruits of Caloncoba glauca. Their structures were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques, by chemical evidence and by comparison with literature data. The new compounds were evaluated for their in vitro cytotoxicity against five human cancer cell lines.     

Chemical constituents from the root of Damnacanthus officinarum Huang

The present phytochemical investigation on Damnacanthus officinarum Huang led to the isolation of a new anthraquinone glycoside named digiferruginol-11-O-β-gentiobioside, along with six known compounds, including anthraquinone glycosides, iridoid glycoside and etc. In the study, compounds (2–7) were isolated for the first time from D. officinarum Huang and Damnacanthus genus. The found of compounds (1–4, 6 and 7) indicate a close relationship between D. officinarum Huang and Morinda officinalis, which may be as chemotaxonomic markers for the tribe Morindeae     

Norbergenin derivatives from the stem bark of Diospyros sanza-minika (Ebenaceae) and their radical scavenging activity

Three new norbergenin derivatives, 11-O-p-hydroxybenzoylnorbergenin, 4-O-(3′-methylgalloyl)norbergenin and 4-O-syringoylnorbergenin were isolated from the stem bark of Diospyros sanza-minika, along with three known compounds: norbergenin, 4-O-galloylnorbergenin and quercitol. Their structures were established on the basis of 1D and 2D NMR experiments and mass spectrometry. Some of the above compounds showed radical scavenging properties in a DPPH solution assay.     

Chemical constituents from Nuxia congesta and their chemotaxonomic significance

A phytochemical investigation of the aerial parts of Nuxia congesta led to the isolation and identification of fifteen compounds, including a new flavonoid, nuxiacin (5-hydroxy-3,8-dimethoxy flavone-7-O-β-D-glycopyranoside) (1). The structure of the new compound was determined using various spectroscopic data including 1D and 2D NMR and mass spectroscopy. All compounds were isolated from N. congesta for the first time. The chemotaxonomic significance of the isolated compounds in the family Stilbaceae and order Lamiales are discussed herein.     

New diterpenoids from Caesalpinia species and their cytotoxic activity

Chemical investigation on Caesalpinia crista afforded two new diterpenoids, 6β-cinnamoyloxy-7β-acetoxyvouacapen-5α-ol and 6β,7β-dibenzoyloxyvouacapen-5α-ol and on Caesalpinia pulcherrima another new diterpenoid, 12-demethyl neocaesalpin F along with several known constituents. The structures of the new compounds were settled from their 1D and 2D NMR spectral data. The cytotoxicity of these compounds was measured on two different cancer cell lines.     

Alkaloids from Galanthus fosteri

Three new alkaloids, oxoincartine, 3,11-O-diacetyl-9-O-demethylmaritidine and 11-O-acetyl-9-O-demethylmaritidine together with seven known compounds namely, incartine, galanthamine, galanthine, 9-O-methylpseudolycorine, N,O-dimethylnorbelladine, hordenine and vittatine were isolated from Galanthus fosteri Baker (Amaryllidaceae). Their structures were elucidated by spectroscopic analyses (UV, IR, MS, CD and 1D/2D NMR). Cholinesterase inhibitory activity potentials of the compounds were also determined.     

New germacranolides and other sesquiterpene lactones from Dicoma species

Two subspecies of Dicoma anomala afforded, in addition to known compounds, an eudesmanolide, a guaianolide and four germacranolides, the latter being closely related 8, 12-lactones. D. schinzii gave three new germacranolides and D. zeyheri a pair of isomeric acetylenic compounds. The structures were elucidated by highfield ¹H NMR spectroscopy. The chemotaxonomic situation of this genus is discussed briefly.     

Chemical constituents from Sarcopyramis nepalensis Wall

One new megastigmane glycoside 1 and two new terpenic glycosides 2 and 3, along with three known compounds, roseoside, pumilaside A, and terminolic acid were isolated from Sarcopyramis nepalensis Wall. The structures of these new compounds were elucidated on the basis of 1D, 2D NMR, MS spectroscopic analysis, and chemical methods.     

Cytotoxic meroterpenoids from the macroalga Cystoseira abies-marina

Two new meronorsesquiterpenes (cystoazorones A and B) and two new meroditerpenes (cystoazorols A and B), along with benzoic acid were isolated from the brown macroalga Cystoseira abies-marina. The structures of the new compounds were established by 1D and 2D NMR as well as HRMS spectral analysis. The in vitro cytotoxicity and antioxidant activity of the isolated compounds were also evaluated. Cystoazorones A and B, and cystoazorol A exhibited in vitro growth inhibitory activity against HeLa cells. The HeLa cell line in log phase was found to be more sensitive to cystoazorol A than when it was in lag phase. Cystoazorol A also showed a selectivity index higher than taxol, which was used as a positive control. Cystoazorols A and B were found to be the strongest antioxidants among the compounds tested.     

Norlignan glycosides from the leaves of Molineria latifolia

Two new norlignan glycosides, molinerioside D (5) and molinerioside E (9), were isolated from the methanol extract of fresh leaves of Molineria latifolia. Their structures were determined using spectroscopic evidence, such as 1D and 2D NMR and HR-ESI-MS studies. The structure of molinerioside D (5) was determined to be a norlignan glycoside with a C6-C5-C6 skeleton, while the structure of molinerioside E (9) was determined to be a glucosyl-fused norlignan derivative. In addition to the new compounds, twenty known compounds were found in the extract of M. latifolia fresh leaves.     

Chemical constituents of the roots of Eupatorium chinense and their anti-inflammatory activities

In this study, three new compounds (1-3), together with fifteen known ones (4-18) were isolated from a petroleum ether extract of the roots of Eupatorium chinense. The structures of new compounds were elucidated by 1D, 2D nuclear magnetic resonance (NMR), circular dichroism spectrum (CD), mass spectrum (MS) along with other spectroscopy methods. In addition, twelve compounds were evaluated in vitro for their anti-inflammatory activities, while compounds 3 and 5 exhibited moderate activities with inhibition rates of 23.08 % and 25.19 %, respectively.     

Bergenin glycosides from Rodgersia aesculifolia

Phytochemical investigation on Rodgersia aesculifolia afforded twenty-three compounds, including three bergenin glycosides, previously unknown in nature, together with twenty known compounds. Their structures were elucidated by the extensive use of 1D and 2D NMR experiments, along with IR and HRESIMS spectra. This is the first report of bergenin glycosides from nature.     

Quantitative analysis of polyphenols and antioxidant activity in four Daphne L. species

The content of biologically active phenolic compounds (total polyphenols, tannins, flavonoids, and phenolic acids) were determined using spectrophotometry in four wild Croatian species of Daphne L. in the family Thymelaeaceae (Daphne alpina, D. cneorum, D. laureola, and D. mezereum). The concentration of total flavonoids (TF) was highest in the leaves of these Daphne species (0.12?C0.51% dry herb weight, DW) whereas the content of other phenolic compounds analyzed were highest in the roots, including total polyphenols (TP; 2.71?C19.03% DW), tannins (T; 1.14?C7.39% DW), and total phenolic acids (TPA; 0.12?C0.87% DW). D. alpina contained the highest amount of polyphenols, with the exception of flavonoids, where maximum concentrations were found in D. laureola. We also examined the antioxidant activity of leaf, stem, and root extracts. All extracts analyzed demonstrated high free radical scavenging activity with the highest concentration in the leaf extracts of D. alpina. Leaf extracts of D. cneorum showed the highest antioxidant activity in a ??-carotene bleaching assay.     

Flavonoid dimers from the aerial parts of Conyza stricta

A new flavonoid dimer, strictatin (10), was identified from the aerial part of Conyza stricta, in addition to eleven known compounds. The structure of compound 10 was determined by spectral analyses, including 1D, 2D NMR and HR-ESI-MS experiments. All compounds were identified from Conyza stricta for the first time and flavonoid dimers were firstly reported from the family Asteraceae. The chemotaxonomic significance of the identified metabolites was discussed.