New species and combinations in neotropical Lecythidaceae

Lecythis barnebyi Mori andCorythophora amapaensis Pires ex Mori & Prance are described and the following new combinations are coined:Lecythis brancoensis (R. Knuth) Mori,L. schwackei (R. Knuth) Mori,L. alutacea (A. C. Smith) Mori,L. lurida (Miers)Mori, L. holcogyne (Sandwith)Mori, L. corrugata Poiteau subsp.rosea (Spruce ex Berg) Mori, andCorythophora labriculata (Eyma) Mori & Prance.     

New species in Adiantum and Pteris (Pteridaceae) from the Andes

We describe, discuss, and illustrate four new species, one inAdiantum (A. capillatum A. R. Sm. &; Prado, from Ecuador) and three species inPteris (P. lellingeri A. R. Sm. &; Prado, from Bolivia;P. venezuelensis A. R. Sm. &; Prado, from Venezuela; andP. websteri A. R. Sm. &; Prado, from Ecuador, Colombia, and Bolivia).     

New and noteworthy plants from Great Barrier Reef sand cays,Australia

Observations are presented on new and critical plants from the northern sand cays on the Great Barrier Reef, Queensland, Australia, based mainly on recent collections made by David R. Stoddart and Ralf Buckley. New species and varieties are described:Lepturus stoddartii (Poaceae),Boerhavia fistulosa var.fistulosa and var.puberuliflora (Nyctaginaceae),Boerhavia albiflora var.heronensis, Spermacoce everistiana (Rubiaceae), andSpermacoce buckleyi; a new combination is made:Diospyros ferrea var.compacta (R. Br.) (Ebenaceae); and additional taxonomic notes are given onBoerhavia, Euphorbia (Euphorbiaceae), andAbutilon (Malvaceae).     

Interaction Between Umami Peptide and Taste Receptor T1R1/T1R3

The umami taste receptor is a heterodimer composed of two members of the T1R taste receptor family: T1R1 and T1R3. The homology models of the ligand binding domains of the human umami receptor have been constructed based on crystallographic structures of the taste receptor of the central nervous system. Furthermore, the molecular simulations of the ligand binding domain show that the likely conformation was that T1R1 protein exists in the closed conformation, and T1R3 in the open conformation in the heterodimer. The molecular docking study of T1R1 and T1R3 in complex with four peptides, including Lys–Gly–Asp–Glu–Ser–Leu–Leu–Ala, Ser–Glu–Glu, G1u–Ser, and Asp–Glu–Ser, displayed that the amino acid residue of SER146 and Glu277 in T1R3 may play great roles in the synergism of umami taste. This docking result further validated the robustness of the model. In the paper, binding of umami peptide and the T1R1/T1R3 receptor was first described and the interaction is the base of umami activity theory.     

The taxonomy of eriodon and notes on other South American genera of brachytheciaceae with erect capsules

Eriodon is reduced from five species to two.Eriodon radicalis is recognized asEntodontopsis radicalis;Eriodon longipes asPorotrichodendron longipes; andE. brevisetus as synonymous withLindigia debilis. Mandoniella, Stenocarpidiopsis andLepyrodontopsis are discussed and illustrated.Lepyrodontopsis is transferred to the new familyLe pyrodontopsidaceae, near the Meteoriaceae. The following nomenclatural trans fers are proposed for Rozea:R. andrieuxii f.chrysea andR. andrieuxii var.bour gaeana. Sciuroleskea is transferred to an alliance withStereophyllum,Juratzkaea, Entodontopsis, Stenocarpidium andJuratzkaeella. The following transfers are proposed:Sciuroleskea roseorum (Williams asRozea) Buck andJuratzkaea argentinica (Thér. asJ. seminervis var.argentinica) Buck. A key to the erect-capsuled South American genera retained in the Brachytheciaceae is provided.     

Metabolomics investigation of flavonoid synthesis in soybean leaves depending on the growth stage

Soybean (Glycine max L.) leaves have unique nutraceutical and pharmacological benefits, and have been widely used as a source of healthy and functional food stuffs in Korea. In this study, we investigated the phytochemical metabolomic changes of soybean leaves depending on growth stages (maturation period) assessed based on UPLC–QTOF–MS analysis. Principal component analysis was carried out to trace the metabolite profiles of the phytochemicals from the vegetable stage (1D) through the seven reproductive stages (R1–R7). On the loading plot, significant changes in the contents of metabolites were found during the growth, and eight flavonoid kaempferol glycosides (2, 3, 6, 8, and 10), daidzein (14), genistein (17), and coumestrol (19) were evaluated as growth markers among the 19 isolated metabolites. The kaempferol glycosides were increasingly synthesized from the 1D to the R6 stage but decreased rapidly at stages R7–R8. The extensively synthesized daidzein and genistein were shown during seed growth in the pod (R5–R6), while coumestrol was increased significantly at stages R7–R8 (maturity period). The synthetic pathway of the flavonoids could be elucidated based on the concentration of the individual metabolites. These results demonstrate that the metabolite production changed depending on the growth stage; a possible pathway could be deduced using metabolomic analysis to provide information regarding physiological characterization and optimal harvesting time for crops.     

New taxa and combinations in Malvastrum A. Gray (Malvaceae: Malveae)

The genusMalvastrum A. Gray is interpreted to include 22 taxa in 14 species. Seven taxa are here described as new, namely:M. americanum var.stellatum,M. tomentosum subsp.pautense,M. bicuspidatum subsp.campanulatum,M. bicuspidatum subsp.oaxacanum, M. bicuspidatum subsp.tumidum var.tumidum, M. bicuspidatum subsp.tumidum var.glabrum, andM. coromandelianum subsp.fryxellii. In addition, two new combinations are proposed, namely:M. tomentosum andM. coromandelianum subsp.capitato-spicatum.     

Notes on capitate Venezuelan Rhynchospora (Cyperaceae)

Two new combinations, Rhynchospora imeriensis (Kükenthal) W. Thomas and R. planifolia (T. Koyama) W. Thomas, and a new name, R. capillifolia W. Thomas, are provided for capitate species of Rhynchospora occurring in Venezuela. A new section of capitate species with white spikelets, sect. Rigidifolia W. Thomas, is described, and its six included species are listed, discussed, and keyed. Lectotypes are designated for R. duckei R. Gross and R. longibracteata Boeckeler. Two species are illustrated.     

Protonation,alkylation, addition and redox reactions of 16, 17 and 18 valence electron [Mo(L)(NO)('S4')] complexes [L = SPh,PMe3, NO; 'S4'2– = 1,2-Bis-(2-mercaptophenylthio)ethane(2-)]

In the quest for complexes modelling functional characteristics of metal sulfur oxidoreductases, a series of molybdenum nitrosyl complexes with sulfur-dominated coordination sphere was synthesized. Treatment of the 16, 17 and 18 valence electron (VE) complexes [Mo(L)(NO)('S₄')] (1–3) [L?=?SPh (1), PMe₃ (2), NO (3), 'S₄'^2–?=?1,2-bis-(2-mercaptophenylthio) ethane(2-)] with the Brönsted acid HBF₄ resulted in formation of different types of products. 1 and 3 were reversibly protonated at one thiolate atom of the 'S₄'^2– ligand;2, however, yielded the phosphonium salt [HPMe₃]BF₄ and the dinuclear [Mo(NO)('S₄')]₂. Alkylation of 1, 2 and 3 by Me₃OBF₄ or Et₃OBF₄ uniformly resulted in high yields of [Mo(L)(NO)(R-'S₄')]BF₄ complexes [L?=?SPh: R?=?Me (5), Et (6); L?=?PMe₃: R?=?Me (7); L?=?NO: R?=?Me (8), Et (9)] in which one thiolate atom of the 'S₄'^2– ligand had become alkylated; the NMR spectra of 5, 6, 8 and 9 indicated that only one out of four theoretically possible diastereoisomers had formed. 5 and 6 were characterized also by single-crystal X-ray structure analyses. A comparison of ν(NO) bands and redox potentials (cyclic voltammetry) of parent complexes and alkylated derivatives showed that alkylation leads to a decrease in electron density at the molybdenum center and to a positive shift in redox potentials. The 16 VE complex 1 could be reduced, also chemically, to give the corresponding 17 VE anion [1]^–, and inserted elemental sulfur into the Mo-SPh bond, forming the 18 VE phenylperthio complex [Mo(η²–SSPh)(NO)('S₄')] (11) which, upon reaction with PPh₃, gave SPPh₃ and regenerated the parent complex 1. These results are discussed with regard to the sequence of proton and electron transfer steps occurring in substrate conversions catalyzed by metal sulfur oxidoreductases.     

New combinations for Panicum subgenus Panicum and subgenus Dichanthelium (Poaceae) of the Southeastern United States

Twenty-two new varietal combinations are made for the treatment of the genusPanicum of the Southeastern United States. The following 3 new combinations are made in the subgenusPanicum:Panicum rigidulum var.elongatum, P. rigidulum var.pubescens, P. rigidulum var.combsii. The following 19 new combinations are made in the subgenusDichanthelium:P. strigosum var.glabrescens P. strigosum var.leucoblepharis, P. dichotomum var.roanokense, P. dichotomum var.lucidum, P. dichotomum var.ramulosum, p. dichotomum var.mattamuskeetense, P. dichotomum var.yadkinense, P. ensifolium var.curtifolium, P. chamaelonche var.breve, P. portoricense var.nashianum, P. acuminatum var.fasciculatum, P. acuminatum var.unciphyllum, P. acuminatum var.columbianum, P. acuminatum var.lindheimeri, P. acuminatum var.densiflorum, P. acuminatum varlongiligulatum, P. acuminatum var.leucothrix, P. ovale var.pseudopubescens, andP. ovale var.villosum.     

Synthesis of some quinolinyl chalcone analogues and investigation of their anticancer and synergistic anticancer effect with doxorubicin

Two derivatives of 2-(4-acetylanilino)quinolines (IIIa, b) were synthesized as scaffolds for synthesis of open chalcone analogues (Va-f) through Claisen-Schmidt condensation with a set of aromatic aldehydes (IVa-d). Derivatives (Va, b) were further manipulated into cyclic ??,??-unsaturated ketones by Michael-addition of acetylacetone and ethylacetoacetate affording derivatives (VI?CVII). Deethoxycarboxylation of derivatives (VIIa, b) afforded cyclohexenons (VIIIa, b) allowing formation of a mini library of ??,??-unsaturated ketones for screening their anticancer and synergistic anticancer effect with doxorubicin using colon cancer cell line (Caco-2). Two open enones, (Vb) and (Ve), showed significant anticancer activity with IC₅₀ of 5.0 and 2.5 ??M respectively. Only one cyclic enone, (VIa) showed synergistic anticancer activity with doxorubicin at 10 ??M.     

Revision of Plerandra (Araliaceae). I. A synopsis of the genus with an expanded circumscription and a new infrageneric classification

Phylogenetic studies have demonstrated that Schefflera, the largest genus of Araliaceae, is grossly polyphyletic, comprising five distinct clades within the family. In an effort to establish monophyletic genera among the elements that currently comprise Schefflera, the genus Plerandra is expanded to encompass all of the members of one of these clades. In this synoptical revision, a new infrageneric classification is presented (along with a key) in which six subgenera are recognized. Four of these subgenera are newly described (Plerandra subgenera Canacoschefflera, Costatae, Gabriellarum, and Veilloniorum) and a fifth represents a new combination (Plerandra subg. Dizygotheca). A total of 33 species (one with two subspecies) are accepted, one of which is newly described (P. veilloniorum), and 22 new combinations are made (P. actinostigma, P. baillonii, P. cabalionii, P. costata, P. crassipes, P. elegantissima, P. elongata, P. emiliana, P. gabriellae, P. leptophylla, P. nono, P. osyana, P. osyana subsp. toto, P. pachyphylla, P. pancheri, P. plerandroides, P. polydactylis, P. reginae, P. seemanniana, P. tannae, P. vanuatua, P. veitchii). Neotypes are provided for six accepted names and one heterotypic synonym, and lectotypes are designated for 13 accepted names and 16 heterotypic synonyms. For each accepted species, full synonymy is provided along with geographic range and notes.     

Enhanced β-turn conformational stability of tripeptides containing ΔPhe in cis over trans configuration

Conformations of three pairs of dehydropeptides with the opposite configuration of the ΔPhe residue, Boc-Gly-Δ^Z/EPhe-Phe-p-NA (Z- p -NA and E- p -NA), Boc-Gly-Δ^Z/EPhe-Phe-OMe (Z-OMe and E-OMe), and Boc-Gly-Δ^Z/EPhe-Phe-OH (Z-OH and E-OH) were compared on the basis of CD and NMR studies in MeOH, TFE, and DMSO. The CD results were used as the additional input data for the NMR-based calculations of the detailed solution conformations of the peptides. It was found that Z- p -NA, E- p -NA, Z-OMe, and Z-OH adopt the β-turn conformations and E-OMe and E-OH are unordered. There are two overlapping type III β-turns in Z- p -NA, type II’ β-turn in E- p -NA, and type II β-turn in Z-OMe and Z-OH. The results obtained indicate that in the case of methyl esters and peptides with a free carboxyl group, Δ^ZPhe is a much stronger inducer of ordered conformations than Δ^EPhe. It was also found that temperature coefficients of the amide protons are not reliable indicators of intramolecular hydrogen bonds donors in small peptides.     

New variety and nomenclatural changes in neotropical Gaultheria (ericaceae)

Gaultheria sclerophylla var.hirsuta Luteyn from Ecuador is described, illustrated, and discussed, and the following new combinations are validated:Gaultheria buxifolia var.elassantha (A. C. Smith) Luteyn,G. buxifolia var.secunda (E. J. Remy) Luteyn,G. lanigera var. rufolanata (Sleumer) Luteyn,G. strigosa var.revoluta (A. C. Smith) Luteyn,G. eriophylla var.mucronata (E. J. Remy) Luteyn,G. alnifolia var.grata (A. C. Smith) Luteyn,G. serrata (Vell. Conc.) Sleumer ex Kinoshita-Gouvêa.     

Novel alkyl alkanethiolsulfonate sulfhydryl reagents. Modification of derivatives ofl-cysteine

A simple, general scheme for the synthesis of sulfhydryl-specific alkyl alkanethiolsulfonate (RSSO₂R′) reagents where R′ is methyl, has been developed. Two new reagents, methyl aminoethanethiolsulfonate (2) and methyl benzylthiolsulfonate (3) were synthesized. These were used to modify stoichiometrically and selectively under mild conditions the sulfhydryl groups ofN-acetyl-l-cysteine ethyl ester (4),N-acetyl-l-cysteinep-nitroanilide (7), glutathione, and the A chain of bovine insulin. The corresponding β-S-(β-aminoethanethiol) and β-S-(benzylthiol) derivatives ofl-cysteine and of the peptides were afforded. The characteristics and significance of these reactions and products are discussed.     

Nomenclatural changes in Myrteola and Myrceugenia (Myrtaceae)

The following new combinations are made:Myrteola phylicoides (Benth.) Landrum,Myrteola phylicoides var.glabrata (Berg) Landrum,Myrceugenia alpigena var.fuliginea (Berg) Landrum,Myrceugenia ovata var.regnelliana (Berg) Landrum, andMyrceugenia pilotantha var.nothorufa (Legrand) Landrum.     

A taxonomic revision of the Antennaria rosea (Asteraceae: Inuleae: Gnaphaliinae) polyploid complex

TheAntennaria rosea species complex is circumscribed to contain four subspecific taxa. A complete synonymy and key to the subspecies ofA. rosea is presented. The following new combinations are proposed:Antennaria rosea subsp.arida (E. Nels.) R. Bayer,A. rosea subsp. confinis (Greene) R. Bayer, andA. rosea subsp. pulvinata (Greene) R. Bayer. The affinities ofA. rosea to other species ofAntennaria are discussed and a key to separateA. rosea from related polyploid complexes is provided.     

Photophysics of novel coumarin-labeled depsipeptides in solution: sensing interactions with SDS micelle via TICT model

N-Acylbenzotriazoles enable the synthesis (69–92 % yield) of blue to green fluorescent coumarin-labeled depsidipeptides 8a–f (quantum yields 0.004–0.97) and depsitripeptides 12a–d (quantum yields 0.02–0.96). Detailed photophysical studies of fluorescent coumarin-labeled depsipeptides 8a–f and 12a–d are reported for both polar protic and polar aprotic solvents. 7-Methoxy and 7-diethylaminocoumarin-3-ylcarbonyl depsipeptides 8c,f and 12d are highly solvent sensitive. These highly fluorescent compounds could be useful for peptide assays. Further photophysical studies of 7-diethylaminocoumarin-labeled depsipeptides 8c,12d within the micellar microenvironment of SDS reflect their ability to bind with the biological membrane, suggesting potential applications in the fields of bio- and medicinal chemistry.