Phytochemical and chemotaxonomic study on the leaves of Rhododendron amesiae

The phytochemical study of the leaves of Rhododendron amesiae (Ericaceae) led to the isolation and identification of 19 compounds, including six diterpenoids (1–6), six triterpenoids (7–12) and seven flavonoids (13–19). The chemical structures of these compounds were identified by spectroscopic data, as well as by comparison with previously reported data in literature. This is the first systematic study on the chemical constituents of Rhododendron amesiae. All the compounds were isolated from this plant for the first time. Compounds 12, 14 and 15 were first isolated and reported from the genus Rhododendron and the family Ericaceae. Furthermore, the chemotaxonomic significance of these compounds was discussed.     

α-pyrone derivatives from endophytic fungus Diaporthe sp. RJ-41

A new α-pyrone derivative 1 and six known α-pyrone derivatives 2–7, along with known compounds 8–10 were isolated from the fermentation products of the endophytic fungus Diaporthe sp. RJ-41. Among them, nine compounds (1–9) were reported for the first time from the genus Diaporthe. This work expanded the knowledge of the chemical diversity of the genus Diaporthe, and the chemotaxonomic significance of the isolates was also discussed.     

Host shift capability of a specialist seed predator of an invasive plant: roles of competition, population genetics and plant chemistry

Acanthoscelides macrophthalmus is a seed predator that has become widely distributed along with its native host, Leucaena leucocephala (Mimosoideae), which is a neotropical leguminous tree and one of the most invasive plants worldwide. Previous studies revealed that A. macrophthalmus is able to host-shift to several mimosoid species. Here, we aim to test the host-shift potential to other mimosoid and non-mimosoid plants and possible roles of interspecific competition, genetic background, and plant chemistry in host-shift. First, we found that A. macrophthalmus predator completed development on two new hosts: pigeon pea Cajanus cajan and Cajanus scarabaeoides (Faboideae), by rearing from seeds collected in South/Southeast Asia and Hawaii. In contrast, in most regions, both Cajanus species were infested only by other beetle species. Second, we performed no-choice tests using 11 leguminous plants, covering all three subfamilies as potential hosts, including the two new hosts. A Taiwanese A. macrophthalmus population reared in the laboratory on Leucaena did not deposit eggs on any of the seeds of each tested species. To compare host-shift responses between populations, we also used a Hawaiian A. macrophthalmus population that had completed its development on freshly collected Leucaena seeds from the field. This population deposited eggs onto and hatching larvae burrowed into C. cajan seeds, although none developed beyond the larval stage. Third, the surface chemical composition of seed-pods of L. leucocephala and the two Cajanus species was dissimilar, although that of seeds was highly similar. Finally, all of the host-shifting A. macrophthalmus populations shared the same haplotypic group.     

Chemical constituents from Euphorbia hirta

Thirty-one compounds, including fourteen triterpenoids (1–14), seven coumarins (15–21), four lignans (22–25), and six diterpenes (26–31) were isolated from the aerial part of Euphorbia hirta. The structures were elucidated by spectroscopic methods and by comparison of their reported spectroscopic data. These compounds have shown the chemical relationships between this plant and other species from the genus Euphorbia.     

Chemical constituents of sponge Pseudoceratina sp. and their chemotaxonomic significance

The chemical investigation of Pseudoceratina sp. led to the isolation of six compounds including tyrosine brominated isoxazoline alkaloids (1 and 2), polyketide (3), and 5α,8α-epidioxysterols (4–6). The structures of these compounds were identified by comparison of NMR and MS spectroscopic data with those previously reported. Compounds 3–6 were isolated for the first time from sponges of the genus Pseudoceratina. The chemotaxonomic significance of these compounds was discussed.     

A new acorane sesquiterpenes of Lysionotus pauciflorus maxim. Form Guizhou province,China

A new acorane sesquiterpene (1), together with fourteen known compounds were isolated from the whole plant of Lysionotus pauciflorus Maxim. The chemical structures of the compounds were identified by physio-chemical properties and 1D-NMR, 2D-NMR, ESI-MS, IR and ECD spectra. Among them, six compounds (1, 4, 6, 7, 13, 15) were first found in the genus Lysionotus. The chemotaxonomic significance of the isolated compounds in the genus Lysionotus and family Gesneriaceae were discussed.     

Iridoid glucosides from the stems of three bioactive Brazilian Faramea species (Rubiaceae)

In this paper our previous chemical study of the anti-dengue active species Faramea bahiensis, Faramea hyacinthina and Faramea truncata (synonym of Faramea caudata) (Rubiaceae) is complemented by isolating from their stems, through a combination of silica gel and Sephadex LH-20 column chromatography and reversed-phase solid-phase extraction, the known iridoid glucosides monotropein (1), monotropein methyl ester (2) and 10-deacetylasperulosidic acid (3). The structures were established by HPLC-DAD-MS/MS analysis, NMR spectroscopy and comparison with literature data. This is the first report on the occurrence of these compounds in the genus Faramea Aubl. This work contributes to expand the knowledge of the chemical diversity of this botanical genus, of which a limited number of identified compounds have been reported.     

Prenylated anthranoids from Psorospermum species

The chemical composition of the root extracts of two Psorospermum sp. from the Ivory Coast is reported. Together with previously known compounds, acetylvismione F and 2-geranylemodin anthrone were isolated from P. corymbiferum, and vismione G from P. glaberrimum. Geranyl substitution is confirmed to be a typical feature of this genus.     

Chemical constituents isolated from the roots of Sanguisorba officinalis L. and their chemotaxonomic significance

Phytochemical investigation of the roots of Sanguisorba officinalis L. led to the isolation of thirty-eight compounds, including seventeen triterpenoids (1–17), six monoterpenoid glycosides (18–23), six flavonoids (24–29), six phenols (30–35), two glycosides (36–37), and one lignan (38). The chemical structures of these compounds were elucidated on the basis of spectral data and by comparisons of spectroscopic data with reported values in the literature. Compounds 18, 29, and 36–37 were the first to be reported in the family Rosaceae, compounds 10, 12, 15, 27–28, and 38 were firstly identified from the genus Sanguisorba, and compound 11 was obtained from S. officinalis for the first time. The chemotaxonomic significance of these isolated compounds has also been discussed.     

Chemical constituents from the roots of Asarum sieboldii Miq. var. Seoulense Nakai

Fourteen compounds were isolated from the 95% ethanol reflux extract of Asarum sieboldii Miq. var. Seoulense Nakai, including five phenanthrene derivatives (1–5), three isobutyl amides (6–8), three phenylpropanoids (9–11) and three lignins (12–14). The structures of these compounds were identified by spectroscopic methods and by comparison with the reported spectroscopic data. Among them, compounds 6 and 11 were firstly reported from the family Aristolochiaceae, and compounds 3 and 4 were reported for the first time from the genus Asarum. Additionally, compounds 1, 2 and 8 were isolated from A. sieboldii Miq. var. Seoulense Nakai for the first time. These compounds have shown chemical relationships between A. sieboldii Miq. var. Seoulense Nakai and other species of Asarum as well as those found in the genus Aristolochia in the family Aristolochiaceae.     

Secondary metabolites from Spiranthes sinensis (Orchidaceae)

One new flavonol glycoside (1) and nine known compounds (2–10) were obtained from the n-BuOH soluble fraction of the whole plants of Spiranthes sinensis. The structure of compound 1 was elucidated based on the combination of spectroscopic (¹H-NMR, ¹³C-NMR, HSQC, and HMBC as well as HR-ESI-MS) and chemical methods. The occurrences of eight compounds (2-9) in this genus were firstly reported while five of them (2–6) were obtained from Orchidaceae for the first time. Furthermore, the chemotaxonomic significance of these compounds was discussed.     

Chemical constituents from the calyces of Physalis alkekengi var. franchetii

One new monoterpenoid glycoside (1), together with seven known compounds, including two alkaloids (2–3), three phenylpropanoids (4–6), and two nucleosides (7–8) were isolated from the calyces of Physalis alkekengi var. franchetii. Their structures were elucidated by a combination of detailed spectroscopic analyses, chemical methods, and comparison with reported data. These eight compounds were isolated for the first time from the genus Physalis. The chemotaxonomic significance of these compounds was summarized.     

Phytochemical and chemotaxonomic study on Dictamnus angustifolius G. Don ex Sweet (Rutaceae)

A phytochemical investigation of Dictamnus angustifolius led to the isolation of 14 compounds, including six furoquinoline alkaloids (1–6), two sesquiterpenoids (7, 8) and six flavonoids (9–14). The structures of these compounds were identified by spectroscopic methods and a comparison of their data with those reported in the literature. This is the first report of three furoquinoline alkaloids 1–3 and six flavonoids 9–14 from the genus Dictamnus and the first isolation of compounds 4–8 from D. angustifolius. The chemotaxonomic significance of furoquinoline alkaloids and sesquiterpenoids has also been summarized.     

Investigation of chemical compounds from Chlamydomonas sp. KSF108 (Chlamydomonadaceae)

Nine compounds (1–9) including one norisoprenoid (1), one polyol-glycoside (2), three sterols (3–5), three phenols (6, 8, and 9), and one fatty acid (7) were isolated from Chlamydomonas sp. KSF108. Their chemical structures were established using NMR spectroscopic techniques and compared with published data. None of the compounds have been previously reported from the genus Chlamydomonas and they may therefore serve as chemotaxonomic markers for Chlamydomonas sp. KSF108 within the genus.     

The chemotaxonomic classification of Korean Campanulaceae based on triterpene,sterol, and polyacetylene contents

The taxonomic usefulness of selected marker compounds was investigated by analyzing the chemotaxonomy of 25 taxa in the Korean Campanulaceae. Our data permit discrimination of the source plants of crude drugs listed in the Korean Pharmacopoeia and the Korean Herbal Pharmacopoeia. Chemotaxonomic analysis methods were validated, and quantitative measurements of six marker compounds were made using HPLC. Marker compound similarities among taxa were identified through multivariate statistical analyses (principal component analysis and hierarchical cluster analysis). The chemical analysis method was validated with regard to linearity, lower limit of detection, lower limit of quantitation, precision, accuracy, and recovery. The analysis revealed differences in the marker compound composition of each genus. Eight genera comprising Adenophora, Codonopsis, Asyneuma, Campanula, Hanabusaya, Platycodon, Wahlenbergia, and Peracarpa clustered according to the chemical classification. The results indicated that the six marker compounds used in this analysis were useful in identifying Korean Campanulaceae. These marker compound data were able to successfully discriminate among the three species that are sold as the crude drug Adenophorae Radix.     

Phytochemical and chemotaxonomic studies on Dioscorea collettii

A chemical investigation of Dioscorea collettii led to the isolation of twenty-nine compounds, including six steroid saponins (1–6), thirteen monocyclic phenols (7–19), two flavonoids (20–21), three sterols (22–24), and five cyclodipeptides (25–29). The chemical structures of these compounds were elucidated using spectroscopic methods and by comparing their data to that reported in the literature. This study is the first report of compounds 2–4, 7, 14–17, 21, and 23–24 in D. collettii, while compounds 8–13, 18–20, and 25–29 were first isolated from the genus Dioscorea and the family Dioscoreaceae. The chemotaxonomic significance of the isolated compounds is discussed.     

Chemical constituents from the aerial parts of Juncus setchuensis

Juncus setchuensis is a perennial herbaceous plant found in marshes, swamps, and other poorly drained sites. Despite being so abundant in the southwest of China, only one literature reference has reported about its chemical components. The present phytochemical investigation on this plant led to isolations of 13 compounds (including four 9,10-dihydrophenanthrenes, one phenanthrene, one flavonone, two mono-aromatics, one steroid, one anthraquinone and three diterpenoid tanshinones), five of them were isolated form this plant for the first time, four of them, one anthraquinone and three diterpenoid tanshinones, were reported for the first time in this genus. The presence of phenanthrenes, 9,10-dihydrophenanthrenes in the Juncus genus could be of taxonomic importance.     

Chemical constituents with prenyl substitution from the stem and root of Daphne giraldii Nitsche. (Thymelaeaceae)

Phytochemical characterization of the stem and root bark of Daphne giraldii Nitsche. led to the isolation of eight flavones (1–8), six flavans (9–14) and six coumarins (15–20). The structures of these compounds were examined with spectroscopic methods, and also by comparing to previously reported spectroscopic data. Among them, ten compounds (1–3, 9 and 15–20) are reported for the first time for this species, and all compounds with prenyl substitutions have not been identified in other species of genus Daphne, or even in the family Thymelaeaceae. We also describe the chemotaxonomic significance of these compounds.     

Genomic relationships among 11 species in the genus Cajanus as revealed by seed protein (albumin and globulin) polymorphisms

SDS-PAGE analysis of seed albumins and globulins from two pigeonpea, Cajanus cajan, cultivars (DSLR-17 and BDN-2) and ten wild species, including C. cajanifolius, C. lineatus, C. sericeus, C. acutifolius, C. lanceolatus, C. reticulates, C. albicans, C. scarabaeoides, C. volubilis and C. platycarpus, resulted in 34 albumin and 27 globulin polypeptides. Proximity matrix analysis based on electrophoretic banding patterns of albumins and globulins jointly revealed C. cajanifolius to be closest to C. cajan having similarity coefficients of 0.595 and 0.676, respectively. Cluster analysis also exhibited the grouping of C. cajanifolius with C. cajan in one cluster. C. platycarpus has been out grouped. The present analysis more or less agreed with the sectional classification of the genus Cajanus and it has been hypothesized that cultivated pigeonpea has evolved through multi-genomic interaction involving C. cajanifolius and that it has experienced minor genomic reorganization during its divergence.     

Guaianolides from Calea subcordata

Chemical analysis of Calea subcordata yielded three new guaianolides, 8-epi-isobutyrylrupicolin A, 8-epi-isobutyrylrupicolin B and subcordatolide A, which represent the first guaianolide-type sesquiterpene lactones reported in the genus Calea. The structures of the new compounds were established by chemical and spectroscopic methods.