Japonicones A–D,bioactive dimeric sesquiterpenes from Inula japonica Thunb.

Four new dimeric sesquiterpene lactones japonicones A?D (1?4), comprised by eudesmane and guaiane sesquiterpenes, were isolated from the aerial part of Inula japonica Thunb. The structures and stereochemistry of 1?4 were elucidated by use of 2D NMR spectroscopic techniques, X-ray crystallography and modified Mosher method. Japonicone A (1) showed the most potent cytotoxicities against four tumor cell lines, A549, LOVO, CEM and MDA-MB-435.     

Repenins A–D,four new antioxidative coumarinolignoids from Duranta repens Linn.

Phytochemical investigations on the CHCl₃-soluble fraction of the whole plant of Duranta repens Linn. led to the isolation of four new coumarinolignoids, Repenins A–D (1–4), along with the known coumarinolignoids, cleomiscosin A (5) and durantin A (6). Their structures were determined by modern spectroscopic analysis including 1D and 2D NMR techniques and chemical studies. The compounds (1–6) showed potent antioxidative scavenging activity against DPPH radicals, with IC₅₀ values in the range 0.420–0.625 mM. Repenin B (2) displayed the strongest scavenging potential with IC₅₀ values of (0.420 mM).     

Ecliptamines A–D,four new guanidine alkaloids from Eclipta prostrata L.

Four structurally unique guanidine alkaloids ecliptamines A–D (1–4) and one known analog (5) were isolated from the aerial parts of Eclipta prostrata (Asteraceae). Their structures were elucidated on the basis of spectroscopic analyses and chemical methods. The inhibitory activities of 1, 2 and 5 were assayed with respect to cyclooxygenase-1 (COX-1) and -2 (COX-2). Compound 5 showed moderate inhibitory activities against COX-1 and -2 with IC₅₀ values of 3.0 × 10⁻³ M and 8.3 × 10⁻⁴ M, respectively, whereas aspirin as a positive control displayed the IC₅₀ values of 4.2 × 10⁻⁴ M (against COX-1) and 7.1 × 10⁻⁴ M (against COX-2).     

Ximaosteroids A–D,new steroids from the Hainan soft coral Scleronephthya sp.

One novel uncommon steroid, ximaosteroid A (1), possessing an unusual tetrahydrofuran moiety and three new pregnane steroids, ximaosteroids B–D (2–4), were isolated from the Hainan soft coral Scleronephthya sp. Their structures were elucidated on the basis of detailed spectroscopic (IR, MS, and 2D NMR) analysis and by comparison with those reported in the literature.     

Chlorantholides A–F,eudesmane-type sesquiterpene lactones from Chloranthus elatior

Six eudesmane-type sesquiterpene lactones, named chlorantholides A–F, were isolated from the ethanol extract of Chloranthus elatior (Chloranthaceae) together with 12 known compounds. Their structures were elucidated on the basis of extensive spectroscopic analysis, and their absolute configurations were studied by the CD exciton chirality method. The structure of a recently reported eudesmanolide from Chloranthus anhuiensis: 8β-hydroxy-1-oxoeudesma-3,7(11)-dien-12,8-olide, was also revised as 8β-hydroxy-2-oxoeudesma-3,7(11)-dien-12,8-olide (chlorantholide D).     

A facile chemo-, regio- and stereoselective synthesis and cholinesterase inhibitory activity of spirooxindole–pyrrolizine–piperidine hybrids

A series of novel hybrid spiro heterocycles comprising pyrrolizine, spiroxindole and piperidine moieties was synthesized chemo-, regio- and stereoselectively in good yields from 1,3-dipolar cycloaddition reaction of a series of 1-acryloyl-3,5-bisarylmethylidenepiperidin-4-ones with azomethine ylides generated in situ from 5-choloroisatin and l-proline in methanol. These cycloadducts displayed significant cholinesterase inhibitory activity. Among the compounds screened, 8g and 8e, showed maximum inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinestrase (BChE) with IC₅₀ values of 3.33 and 3.13 μM, respectively.     

A New Isoflavonoid from Belamcanda chinensis （L.） DC.

A new isoflavonoid, 5, 6, 7, 3＇-terahydroxy-8, 4＇, 5＇-trimethoxyisoflavone （1）, along with 10 known isoflavonoids, namely 5, 6, 7, 4＇-tetrahydroxy-8-methoxyisoflavone （2）, irilone （3）, genistein （4）, tectorigenin （5）, irigenin （6）, irisflorentin （7）, dichotomitin （8）, dimethyltectorigenin （9）, iridin （10）, and tectoridin （11）, was isolated from the alcohol extract of the rhizomes of Belamcanda chinensis （L.） DC. The structures of these compounds were elucidated on the basis of results of spectroscopic analysis.     

A J E Smith,M.A., D.Phil., D.Sc. (1935–2012)

Abstract

Based on morphology and phylogenetical analyses of nrITS sequences, the Andean endemic Plagiochila (Jamesoniella) dependula is placed in Plagiochila sect. Fuscoluteae. Perianths, oil bodies and sporophytes are described for the first time. Morphologically, P. dependula is characterized by entire, dorsally mostly shortly decurrent, laterally appressed, reniform leaves which are covered by irregular papillae and membranous wax platelets, papillose oil bodies, intercalary androecia with opposite bracts that overlap dorsally, a plagiochilid perianth with an entire mouth, a 250 μm thick capsule wall with thickenings in all layers, large 1–4 celled spores, and bispiral elaters. Morphotypes of Plagiochila fuscolutea with laterally appressed leaves differ from P. dependula by an at least moderately decurrent, broad dorsal leaf base, a ±smooth upper leaf surface, and by its often toothed leaf apices. Plagiochila wolframii is placed in the synonymy of P. fuscolutea. Maximum likelihood and parsimony analyses of 29 Plagiochila ITS sequences resolve P. dependula in a well-supported clade with several other representatives of P. sect. Fuscoluteae. Branch lengths within sect. Fuscoluteae point to a sudden diversification. Accessions of P. heterophylla s.str. from Great Britain (formerly known as P. atlantica) and Costa Rica form an unsupported monophyletic lineage.     

Thaixylomolins D–F,new limonoids from the Thai true mangrove,Xylocarpus moluccensis

Three new limonoids, named thaixylomolins D–F (1–3), were obtained from the seeds of a Thai true mangrove, Xylocarpus moluccensis. The structures of these compounds were identified by extensive NMR and HR-ESIMS/MS investigations. They are further additions to the small group of phragmalins with a C-30 carbonyl moiety, among which thaixylomolins D–E (1–2) contain a Δ^8,14 double bond, whereas thaixylomolin F (3) possesses conjugated Δ^8,9 and Δ^14,15 double bonds.     

Cordatols A–D,four new anti-inflammatory bis-monoterpenoids from Illigera cordata

Cordatols A–D (1–4), four new limonene-derived bis–monoterpenoids plausibly biosynthesized via hetero-Diels-Alder cyclization and sequential hydrolyses of their monoterpene precursors, were isolated from the aerial parts of Illigera cordata. The structures, including absolute configuration, were established by spectroscopic analysis and further confirmed by a two-steps bioinspired chemical transformation. Moreover, compounds 1–4 exhibited moderate in vitro anti-inflammatory activity with IC₅₀ values ranging from 17.5 to 24.6 μM. This study may provide a novel structural template for potential anti-inflammatory agent discovery.     

A study of hybrids between betula pubescens Ehrh. and Betula nana L. from Sutherland—an integrated approach

Summary

Ben Loyal, Sutherland is one of the two sites in Britain where hybrids between Betula pubescens Ehrh. and Betula nana L. have been reported. In view of the confused taxonomic state of the genus Betula, populations in the area were surveyed for distinguishing characteristics of both parents and possible hybrids. Individual plants were investigated by an integration of morphological, biochemical and cytological techniques. The approach and results are considered significant in the wider context of taxonomic study in the genus Betula.     

High-frequency generation and characterization of intergeneric hybrids and haploids from new wheat–barley crosses

Key message

Hybrid plants and a high frequency of maternal haploids were obtained using an efficient wheat–barley hybridization system (with new genotype combinations) and confirmed by several cytological and molecular tools.

Abstract

An efficient hybridization system between wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) is presented on the basis of three new genotype combinations. A particularly high, 14 % frequency of plant regeneration per florets was achieved in the wheat–barley genotype combination of ‘Sichuan’ × ‘Morex’. The genome composition in 42 of the 95 plants regenerated by embryo rescue was determined using ploidy analysis, genomic in situ hybridization and the application of chromosome arm-specific molecular markers (SSR and STS). A high overall frequency (76 %) of maternal (wheat) haploids was observed in all the tests for all three cross combinations. A major implication of this observation is that this new hybridization system represents a useful tool to study the mechanism of uniparental chromosome elimination in cereals.     

Synthesis,characterization and antimalarial activity of quinoline–pyrimidine hybrids

The aim of this study was to synthesize a series of quinoline–pyrimidine hybrids and to evaluate their in vitro antimalarial activity as well as cytotoxicity. The hybrids were brought about in a two-step nucleophilic substitution process involving quinoline and pyrimidine moieties. They were screened alongside chloroquine (CQ), pyrimethamine (PM) and fixed combinations thereof against the D10 and Dd2 strains of Plasmodium falciparum. The cytotoxicity was determined against the mammalian Chinese Hamster Ovarian cell line. The compounds were all active against both strains. However, hybrid (21) featuring piperazine linker stood as the most active of all. It was found as potent as CQ and PM against the D10 strain, and possessed a moderately superior potency over CQ against the Dd2 strain (IC₅₀: 0.157 vs 0.417 μM, ～threefold), and also displayed activity comparable to that of the equimolar fixed combination of CQ and PM against both strains.     

A Review of: “Biological Recognition and Assembly,D. S. Eisenberg,J. A. Lake and C. F. Fox,Eds. Alan R. Liss,New York, 1980; hardbound, 355 pages, $52.00”

Two MMP-7-ase isoenzymes were purified 100-fold from rat muscle extract to apparent homogeneity, with an overall yield of 10%, using homogenization, ultracentrifugation, high-performance aqueous size-exclusion and high-performance anion exchange chromatography methods. When using a TSK G-2000SW column, the separation resulted in a 6-fold purification and 30% recovery of isoenzymes B and C. This concentrated enzyme extract was then passed through a TSK-DEAE-2SW column, using salt gradient at pH 7.5, with an additional 25-fold purification and 90% recovery of the isoenzymes. Two symmetrical enzyme peaks, representing isoenzymes B and C, were detected when performing purity tests of the active enzymes on the anion exchanger and reversed-phase HFLC columns. The procedures involved are extraction, ultracentri-fugation, chromatographies and enzyme assays and require less than five hours.