Phenolic compounds from Dalbergia odorifera

Six new phenolic compounds (1–6), along with five known phenolics (7–11) were isolated from the heartwood of Dalbergia odorifera T. Chen. (Leguminosae). Their structures were determined by spectroscopic techniques including MS, UV, IR, 1D and 2D NMR. Bioassay results showed that compound 1 exhibited cytotoxicity against SGC-7901 and BEL-7402 tumor cell lines, while compounds 3, 5 and 10 showed antibacterial activities against Ralstonia solanacearum.     

Novel alkaloids from the roots of Stemona sessilifolia

Four new Stemona alkaloids, sessilistemonamines A-C (1-3, resp.) and dihydrostemoninine (4), were isolated from the roots of Stemona sessilifolia. Their structures and relative configurations were elucidated by means of in-depth 1D- and 2D-NMR-spectroscopic as well as mass-spectrometric experiments; and the structure of 4 was solved by X-ray single-crystal diffraction. The stereoisomeric compounds 1-3 share an unprecedented tetracyclic decahydro-1H-furo[2',3':4,5]cyclopenta[1,2-b]pyrrolo[1,2-a]azepine nucleus. Compounds 1 and 2 were found to be moderately active in terms of acetylcholinesterase (AchE) inhibition, with IC50 values of 68.8+/-9.5 and 17.1+/-2.5 microM, resp.     

Three new cytotoxic Diels-Alder-type adducts from Morus australis

Three new natural products, australisines A-C (1-3, resp.), were isolated from the stem bark of Morus australis, together with eight related compounds, including mulberrofurans E-G, J, and Q, mongolicin C, chalcomoracin, and kuwanon G. Their structures were fully characterized by spectroscopic methods. Compounds 1-3, mulberrofuran G, mongolicin C, and chalcomoracin showed moderate cytotoxic activities against five human cancer cell lines, with IC50 values ranging from 4.6-9.2 microg/ml, as determined by MTT assay.     

New cytotoxic prostanoids from Taiwanese soft coral Clavularia viridis

Chemical investigation of the AcOEt/MeOH extract of Clavularia viridis collected in Taiwan has afforded four new prostanoids, named claviridins A-D (1-4, resp.). The structures of compounds 1-4 were determined on the basis of 1D- and 2D-NMR techniques, including COSY, HMQC, HMBC, and NOESY experiments. Pharmacological studies revealed that compounds 1-4 exhibited potent cytotoxicity against human cancer cells.     

条纹龙胆的胚胎学研究

首次报道了条纹龙胆（Ｇｅｎｔｉａｎａ ｔｓｒｉａｔａ Ｍａｘｉｍ．）的胚胎学特征,研究结果用以讨论龙胆属狭蕊组（Ｇｅｎｔｉａｎａ Ｓｅｃｔ．Ｓｔｅｎｏｇｙｎｅ）的系统演化关系。主要研究结果如下：花药四室;药壁发育为双子叶型;绒毡层细胞仅来源于初生壁细胞,故绒毡层起源属单型起源,细胞单核,原位退化,属腺质型绒毡层,药隔处的绒毡层细胞经多次平周分裂形成２层至多层的绒毡层细胞,其余部位的绒毡层细胞仍为１     

New flavanones from the leaves of Cryptocarya chinensis and their antituberculosis activity

Four new flavanones, cryptoflavanones A-D (1-4, resp.), together with eight known compounds, were isolated from the leaves of Cryptocarya chinensis. The structures of these new compounds were determined by spectral analyses. Among the isolated compounds, pinocembrin (5) and cryptocaryone (6) exhibited antituberculosis activity against Mycobacterium tuberculosis H(37) Rv strain in vitro with MIC values of 3.5 and 25.0 μg/ml, respectively.     

Bioactive marine prostanoids from octocoral Clavularia viridis

Chemical investigation of the nonpolar extract of soft coral Clavularia viridis resulted in isolation of five new prostanoids, designated as claviridic acids A-E (1-5, resp.), in addition to the known clavulones I-III. Their structures were determined on the basis of spectroscopic techniques, especially HR-ESI-MS, CD, and 2D-NMR experiments. The isolated marine prostanoids exhibited potent inhibitory effect on PHA-induced proliferation of peripheral blood mononuclear cells (PBMC), as well as significant cytotoxic activity against human gastric cancer cells (AGS).     

Chemical constituents of the fermented broth of the ascomycete Theissenia cinerea 89091602

One new betaenone, theissenoic acid (1), together with three new acetogenins, theissenolactones A-C (2-4, resp.), were isolated from the fermented broth of Theissenia cinerea 89091602 isolated in Taiwan. The structures of 1-4 were elucidated by spectroscopic methods. Biological tests revealed that 3 and 4 exhibited moderate growth-inhibitory activities against A549 lung cancer cell line with GI(50) values of 14.9 and 47.9 μM, respectively.     

Influence of (hydroxymethyl)pyridine and pyridine-carboxylic acids, in trans-position to the isopropylamine and amine ligands, on the cytotoxicity of platinum complexes

trans-Pt(II) Complexes with aliphatic amines and planar amines such as (hydroxymethyl)pyridines, and pyridine-3- and pyridine-4-carboxylic acids were synthesized and screened for their potential cytotoxic activity in different cancer cell lines used at the NCI for in vitro screens, i.e., MCF7, NCIH460, and SF268. The complexes studied were designed to differ in geometrical parameters such as the position of the phenyl-group substituents and the nature of the substituents themselves for gathering information about the structure-activity relationships in the trans-complexes. The variation of the substituents turns to be crucial for their biological activity, as both pyridine-3- and pyridine-4-carboxylic acids in trans-position to both amine and isopropylamine ligands provided complexes which displayed no specificity toward any type of cell tested, while (hydroxymethyl)pyridine in trans-position to isopropylamine ligands led to complexes that were clearly more effective against the cell lines tested.     

南亚和东南亚龙胆属(龙胆科)的新名称、新组合及分类注释

本文提出了龙胆属两个种的新名称(Gentiana membranulifera T．N．Ho,G．nudicaulisKurz var. assa- mensis T．N．Ho)和5个变种的新组合[(Gentiana lateriflora Hemsl．var. uncifolia(H．J．Lam)T．N．Ho, G．sumatrana Ridl．var．humifusa(S．Moore)T．N．Ho,G. quadrifaria Bl．var．wightii(Kusnez．)T．N．Ho, G．loerzingii Ridl. var．timida(Kerr)T．N．Ho,G．membranulifera T．N．Ho var．recurvata (Kusnez．)T．N．Ho)〕。     

New bioactive clerodane diterpenoids from the roots of Casearia membranacea

Bioassay-guided fractionation of the acetone extract of the roots of Casearia membranacea furnished three new clerodane diterpenes, caseamembrins S-U (1-3) and the known caseamembrin Q (4). Their structures were established by extensive spectroscopic analyses, especially 2D-NMR. Compounds 1-4 were tested against human tumor cells, including HeLa (cervical epitheloid carcinoma), DLD-1 (colon carcinoma), Daoy (medulloblastoma), and KB (oral epidermoid carcinoma) cell lines. Caseamembrin T (2) exhibited the most potent activity against Daoy cells (ED(50)=10 ng/ml), superior to that of the standard drug mitomycin.     

New names,new combinations and taxonomic notes of Gentiana (Gentianaceae) from South and Southeast Asia

The new names Gentiana membranulifera T. N. Ho and G. nudicaulisKurz var. assamensis T. N. Ho are proposed. The new combinations Gentiana lateriflora Hemsl. var. uncifolia (H. J. Lam) T. N. Ho, G. sumatrana Ridl.var. humifusa (S. Moore) T. N. Ho, G. quadrifaria Bl. var. wightii (Kusnez.)T. N. Ho, G. loerzingii Ridl. var. timida (Kerr) T. N. Ho, and G. membranulifera T. N. Ho var. recurvata (Kusnez.) T. N. Ho are made.     

Chemical constituents of the rhizomes and roots of Gentiana scabra (Gentianaceae)

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BACE1 (Beta‐Secretase) Inhibitory Phenolic Acids and a Novel Sesquiterpenoid from Homalomena occulta

Four phenolic acids, namely 2‐[(Z)‐heptadec‐11‐enyl]‐6‐hydroxybenzoic acid ( 1 ), 2‐[(6Z,9Z,12Z)‐heptadeca‐6,9,12‐trienyl]‐6‐hydroxybenzoic acid ( 2 ), 2‐[(9Z,12Z)‐heptadeca‐9,12‐dienyl]‐6‐hydroxybenzoic acid ( 3 ), and 2‐hydroxy‐6‐(12‐phenyldodecyl)benzoic acid ( 4 ), and one sesquiterpene, asperpenoid ( 5 ), were isolated from the 95% EtOH extract of the roots of Homalomena occulta, among which 1, 2 , and 5 represent new compounds. Further, the phenolic acids 1 – 4 exhibited BACE1 (β‐secretase) inhibitory activity with IC₅₀ values of 6.23±0.94, 6.28±0.63, 7.93±0.38, and 7.65±0.62 μM , respectively.     

Phenolic compounds and ecdysteroids of Diplazium esculentum (Retz.) Sw. (Athyriaceae) from Japan and their chemotaxonomic significance

Four phenolic compounds, (2R)-3-(4′-hydroxyphenyl) lactic acid, trans-cinnamic acid (2), protocatechuic acid (3) and rutin (4), and three ecdysteroids, amarasterone A1 (5), makisterone C (6) and ponastrone A (7) were isolated and identified from the young fronds of Diplazium esculentum (Retz.) Sw. (Athyriaceae). The structures of these compounds were elucidated on the basis of NMR spectral data and comparison with literature values. Compounds 1, 2 and 5–7 were isolated for the first time from title plant. Their structure elucidation and chemotaxonomic significance are explained in detail.     

Three new cytochalasins from the marine-derived fungus Spicaria elegans KLA03 by supplementing the cultures with L- and D-tryptophan

Three new cytochalasins Z₂₁–Z₂₃ ( 1 – 3 , resp.), together with five analogs, 4 – 8 , were isolated from Spicaria elegans KLA03 by the OSMAC (one strain‐many compounds) approach with adding L ‐ and D ‐tryptophan during its cultivation. The structures of new cytochalasins were elucidated on the basis of comprehensive 1D‐ and 2D‐NMR and HR‐ESI‐MS analyses. Cytochalasins Z₂₁ and Z₂₂ ( 1 and 2 , resp.), and compound 5 showed cytotoxic activities against A‐549 cell lines with IC₅₀ values of 8.2, 20.0, and 3.1 μM , respectively.     

Infrageneric phylogeny of the genus Gentiana (Gentianaceae) inferred from nucleotide sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA

The internal transcribed spacers (ITSs) of nuclear ribosomal DNA have been sequenced for 20 species of Gentiana. By incorporating previously released sequence data of eight species, phylogenelic analyses using Fitch parsimony and character-state weighted parsimony were carried out. The length of ITS 1 in the taxa surveyed ranged from 223 to 238 bp and ITS2 from 216 to 234 bp. Sequence divergence between pairs of species ranged from 5.0% to 48.9% in ITS1, from 1.1% to 45.3% in ITS2, and from 3.2% to 46.1% in combined data of ITS1 and ITS2. The ITS phylogeny was generally congruent with morphological classifications except that G. asclepiadea was revealed to be closely related to section Gentiana instead of section Pneumonanthe and section Stenogyne was shown to be a paraphyletic group of the genus Gentiana that would be better excluded from the genus. A divergence among the three European endemic sections and the remaining sections of the genus other than section Stenogyne was revealed. Thus the European species of the genus together do not form a monophyletic group. A close relationship between the sections Chondrophyllae s. l. (including section Dolichocarpa), Cruciata and Pneumonanthe was suggested. The section Frigidae s. l. (including sections Monopodiae, Isomeria, Microsperma, and Phyllocalyx) contained two well-supported clades: section Frigidae s. str. and all others together. The monophyly of the typically dysploid group section Chondrophyllae s. l. was confirmed. Optimization of chromosome numbers on the ITS phylogeny suggested that 2/1 = 26 is a plesiomorphic state for the clade comprising sections Frigidae s. l., Cruciata, Pneumonanthe, and Chondrophyllae s. l., and probably 2n = 20 is a plesiomorphic state for the dysploid group, section Chondrophyllae s. l.     

Phenolic compounds and triterpenes from the roots of Vaccinium dunalianum Wight and their chemotaxonomic significance

Eight phenolic compounds, including two catechins (1 and 2), two proanthocyanidins (3 and 4), three lignans (5–7), and one phenol (8), were isolated from roots of Vaccinium dunalianum Wight (Ericaceae), together with two triterpenes (9 and 10). All of them were isolated from the title plant for the first time. Their chemical structures were established based on the extensive MS and NMR spectroscopic analysis. Compounds 6–10 acquired initially from the genus Vaccinium, showed some significances in chemotaxonomy.