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1. A Concise Total Synthesis of (±)-Trigonoliimine B

Author:
Buyck, Thomas; Wang, Qian; Zhu, Jieping
Source:
Organic letters 2012 v.14 no.5 pp. 1338-1341
ISSN:
1523-7052
Subject:
alkaloids; chemical reactions; chemical structure; solvents
Abstract:
... Trigonoliimine B, a hexacyclic alkaloid, is synthesized in seven steps from simple starting materials. The synthesis features the use of an α-isocyanoacetate as a glycine template for the preparation of an α,α-disubstituted α-amino ester that is appropriately functionalized for the construction of C, D, and E rings. Sulfolane was found to be the solvent of choice for the unprecedented Bischler–Nap ...
DOI:
10.1021/ol300249y

2. Activated carbon supported molybdenum carbides as cheap and highly efficient catalyst in the selective hydrogenation of naphthalene to tetralin

Author:
Pang, Min; Liu, Chunyan; Xia, Wei; Muhler, Martin; Liang, Changhai
Source:
Green chemistry 2012 v.14 no.5 pp. 1272-1276
ISSN:
1463-9270
Subject:
activated carbon; carbides; catalysts; green chemistry; hydrogenation; microwave radiation; molybdenum; naphthalene
Abstract:
... The selective hydrogenation of naphthalene to tetralin has been conducted on Mo₂C/AC prepared by microwave irradiation, and achieved a lasting high conversion with 100% selectivity up to 60 hours. The choice of activated carbon as a support is critical in gaining an ideal balance between high activity and good stability of the catalyst. ...
DOI:
10.1039/c2gc35177c

3. A data envelopment analysis approach to choose transport modes based on eco-efficiency

Author:
Leal, Ilton Curty, Jr.; de Almada Garcia, Pauli Adriano; de Almeida D’Agosto, Márcio
Source:
Environment, development and sustainability 2012 v.14 no.5 pp. 767-781
ISSN:
1387-585X
Subject:
bioethanol; eco-efficiency; experts; growth retardation; guidelines; infrastructure; transportation; Brazil
Abstract:
... The main purpose of this paper is to use data envelopment analysis (DEA) as a support tool to establish a relative eco-efficiency measure for the different bioethanol transportation modes and to prioritize these different modes according to these figures. From a review of previous studies, we selected a set of attributes to be considered in DEA, and then experts were consulted about the importance ...
DOI:
10.1007/s10668-012-9352-x

4. A functional screen for recovery of 4′‐phosphopantetheinyl transferase and associated natural product biosynthesis genes from metagenome libraries

Author:
Owen, J. G.; Robins, K. J.; Parachin, N. S.; Ackerley, D. F.
Source:
Environmental microbiology 2012 v.14 no.5 pp. 1198-1209
ISSN:
1462-2912
Subject:
Escherichia coli; Streptomyces lavendulae; biosynthesis; clones; host range; metagenomics; multigene family; reporter genes; screening; secondary metabolites; transport proteins
Abstract:
... The single‐module non‐ribosomal peptide synthetase BpsA from Streptomyces lavendulae has the unique ability to autonomously synthesize a coloured product (indigoidine) from a single substrate (l‐glutamine), conditional upon activation by a 4′‐phosphopantetheinyl transferase (PPTase) partner. We show that bpsA can be expressed in an entD PPTase gene deleted mutant of Escherichia coli to yield a sen ...
DOI:
10.1111/j.1462-2920.2012.02699.x
PubMed:
22356582

5. A General Preparation of Protected Phosphoamino Acids

Author:
Petrillo, Daniel E.; Mowrey, Dale R.; Allwein, Shawn P.; Bakale, Roger P.
Source:
Organic letters 2012 v.14 no.5 pp. 1206-1209
ISSN:
1523-7052
Subject:
acids; chemical reactions; chemical structure; lupus erythematosus; organic compounds; phosphopeptides
Abstract:
... Fmoc-O-benzyl-l-phosphoserine is an important building block in the synthesis of Forigerimod, a phosphopeptide being investigated for Systemic Lupus Erythematosus (SLE). An efficient one-pot process was developed using inexpensive, readily available starting materials. This general procedure was used to prepare a variety of protected phosphoamino acids. ...
DOI:
10.1021/ol203332j

6. A highly efficient Cu-catalyst system for N-arylation of azoles in water

Author:
Wang, Deping; Zhang, Fuxing; Kuang, Daizhi; Yu, Jiangxi; Li, Junhua
Source:
Green chemistry 2012 v.14 no.5 pp. 1268-1271
ISSN:
1463-9270
Subject:
arylation; bromides; catalysts; catalytic activity; chlorides; green chemistry; imidazoles; ligands; organoiodine compounds
Abstract:
... 6,7-Dihydroquinolin-8(5H)-one oxime (L3) was found to serve as a superior ligand for the CuI-catalyzed N-arylation of imidazoles with aryl iodides, bromides, and electron-deficient chlorides in water. Moreover, the CuI/L3 catalyst system enabled the coupling reactions to take place smoothly with high yields under a low catalyst loading (0.1–1 mol% CuI and 0.2–2 mol% L3). ...
DOI:
10.1039/c2gc35077g

7. Ambient Schmittel Cyclization Promoted by Chemoselective Triazole-Gold Catalyst

Author:
Wang, Qiaoyi; Aparaj, Siddhita; Akhmedov, Novruz G.; Petersen, Jeffrey L.; Shi, Xiaodong
Source:
Organic letters 2012 v.14 no.5 pp. 1334-1337
ISSN:
1523-7052
Subject:
allene; ambient temperature; catalysts; chemical reactions; chemical structure; chemoselectivity
Abstract:
... The Schmittel cyclization was achieved at room temperature through triazole–gold (TA–Au) catalyzed propargyl vinyl ether rearrangement. Other tested [L–Au]⁺ catalysts gave complex reaction mixtures under identical conditions with no desired products observed. Importantly, because of the employment of mild conditions, sterically hindered groups (such as t-Bu) on allene termini were no longer requir ...
DOI:
10.1021/ol300227a

8. Anaerobic benzene degradation under denitrifying conditions: Peptococcaceae as dominant benzene degraders and evidence for a syntrophic process

Author:
van der Zaan, Bas M.; Saia, Flávia Talarico; Stams, Alfons J. M.; Plugge, Caroline M.; de Vos, Willem M.; Smidt, Hauke; Langenhoff, Alette A. M.; Gerritse, Jan
Source:
Environmental microbiology 2012 v.14 no.5 pp. 1171-1181
ISSN:
1462-2912
Subject:
Burkholderiaceae; Peptococcaceae; Rhodocyclaceae; bacteria; benzene; chlorates; electrons; hydrogen; iron; isotopes; microbial communities; microbial growth; nitrates; sulfates
Abstract:
... An anaerobic microbial community was enriched in a chemostat that was operated for more than 8 years with benzene and nitrate as electron acceptor. The coexistence of multiple species in the chemostat and the presence of a biofilm, led to the hypothesis that benzene‐degrading species coexist in a syntrophic interaction, and that benzene can be degraded in syntrophy by consortia with various electr ...
DOI:
10.1111/j.1462-2920.2012.02697.x
PubMed:
22296107

9. Anaerobic degradation of 4‐methylbenzoate via a specific 4‐methylbenzoyl‐CoA pathway

Author:
Lahme, Sven; Eberlein, Christian; Jarling, René; Kube, Michael; Boll, Matthias; Wilkes, Heinz; Reinhardt, Richard; Rabus, Ralf
Source:
Environmental microbiology 2012 v.14 no.5 pp. 1118-1132
ISSN:
1462-2912
Subject:
proteins; electrons; benzoates; genes; Magnetospirillum
Abstract:
... The pathway for anaerobic degradation of 4‐methylbenzoate was studied in the denitrifying alphaproteobacterium Magnetospirillum sp. strain pMbN1. Adaptation studies with whole cells indicated substrate‐dependent induction of the capacity to degrade 4‐methylbenzoate. Differential protein profiling (2D‐DIGE) of 4‐methylbenzoate‐ in comparison with benzoate‐ or succinate‐adapted cells revealed the sp ...
DOI:
10.1111/j.1462-2920.2011.02693.x
PubMed:
22264224

10. Analyzing reaction norm variation in the field vs. greenhouse: Comparing studies of plasticity and its adaptive value in two species of Erodium

Author:
Jacobs, B.S.; Latimer, A.M.
Source:
Perspectives in plant ecology, evolution and systematics 2012 v.14 no.5 pp. 325-334
ISSN:
1433-8319
Subject:
Erodium cicutarium; annuals; case studies; greenhouses; phenotypic plasticity; population; soil nutrients; surveys
Abstract:
... Despite a wide range of experiments characterizing patterns of selection on phenotypic plasticity in controlled environments there has been virtually no research assessing the extent to which these results reflect selection on plasticity expressed in natural populations. To test how well the patterns observed in controlled experiments match the patterns in field populations, we present two case st ...
DOI:
10.1016/j.ppees.2012.04.002

11. An engineered E.coli strain for the production of glycoglycerolipids

Author:
Mora-Buyé, Neus; Faijes, Magda; Planas, Antoni
Source:
Metabolic engineering 2012 v.14 no.5 pp. 551-559
ISSN:
1096-7176
Subject:
Escherichia coli; Mycoplasma genitalium; biosynthesis; diacylglycerols; enzymes; genes; metabolic engineering; plasma membrane
Abstract:
... The glycolipid synthase MG517 from Mycoplasma genitalium catalyzes the glucosyl transfer from UDPGlc to diacylglycerol producing glycoglycerolipids (GGL) (Andrés et al., 2011). The enzyme was functional in E. coli accumulating GGL in the plasma membrane. A metabolic engineering strategy for GGL production was evaluated using this microorganism. To increase the levels of GGL precursors, UDPGlc and ...
DOI:
10.1016/j.ymben.2012.06.001

12. A new eudesmane sesquiterpene glycosides from Liriope muscari

Author:
Jiang, Chang; Liu, Zhi-Hua; Li, Li; Lin, Bin-Bin; Yang, Fan; Qin, Min-Jian
Source:
Journal of Asian natural products research 2012 v.14 no.5 pp. 491-495
ISSN:
1477-2213
Subject:
Liliaceae; Liriope muscari; chemical structure; glycogen; glycosides; nuclear magnetic resonance spectroscopy; palmitic acid; phosphorylase; roots; sesquiterpenoids
Abstract:
... A new eudesmane sesquiterpene glycoside, ophiopogonoside B (1), along with five known compounds, ophiopogonoside A (2), ruscogenin-1-O-[β-d-glucopyranosyl (1 → 2)]-[β-d-xylopyranosyl (1 → 3)]-β-d-fucopyranoside (3), palmitic acid (4), palmitic acid glyceride (5), and β-sitosterol-d-glucopyranoside (6),was isolated from the tuberous roots of Liriope muscari (Decn.) Bailey (Liliaceae). Their structu ...
DOI:
10.1080/10286020.2012.668533

13. A new phenolic compound from the stem of Hymenocardia wallichii

Author:
Suthiwong, Jittra; Poopasit, Kitisak; Yenjai, Chavi
Source:
Journal of Asian natural products research 2012 v.14 no.5 pp. 482-485
ISSN:
1477-2213
Subject:
benzaldehyde; coumarin; monoacylglycerols; nuclear magnetic resonance spectroscopy; squalene; stigmasterol; triterpenoids
Abstract:
... Thirteen compounds were isolated from the stem of Hymenocardia wallichii Tul. A new phenolic compound, wallinol (1), was found in this plant. The other chemical components were squalene (2), stigmasterol (4), homopterocarpin (5), two triterpenes (3 and 13), two benzaldehyde derivatives (6 and 9), three cinnamyl derivatives (7, 11, and 12), a coumarin (8), and a monoglyceride (10). Their structures ...
DOI:
10.1080/10286020.2012.669377

14. An excellent dual recycling strategy for the hypervalent iodine/nitroxyl radical mediated selective oxidation of alcohols to aldehydes and ketones

Author:
Dohi, Toshifumi; Fukushima, Kei-ichiro; Kamitanaka, Tohru; Morimoto, Koji; Takenaga, Naoko; Kita, Yasuyuki
Source:
Green chemistry 2012 v.14 no.5 pp. 1493-1501
ISSN:
1463-9270
Subject:
aldehydes; catalysts; filtration; green chemistry; iodine; iodobenzenes; ketones; methanol; oxidation; recycling; solvents
Abstract:
... Using a recyclable hypervalent iodine reagent 1, the authors have constructed versatile and green methods for the hypervalent iodine and nitroxyl radical-mediated selective oxidation of alcohols to aldehydes and ketones. The recyclable reagent 1 having a unique tetraphenyladamantane structure exhibited almost the same reactivity as the ordinary reagent, phenyliodine diacetate (PIDA), in the hyperv ...
DOI:
10.1039/c2gc16632a

15. A Novel Sensitive Turn-on Fluorescent Zn2+ Chemosensor Based on an Easy To Prepare C3-Symmetric Schiff-Base Derivative in 100% Aqueous Solution

Author:
Zhou, Ying; Li, Zhan-Xian; Zang, Shuang-Quan; Zhu, Yan-Yan; Zhang, Hong-Yan; Hou, Hong-Wei; Mak, Thomas C. W.
Source:
Organic letters 2012 v.14 no.5 pp. 1214-1217
ISSN:
1523-7052
Subject:
aqueous solutions; chemical reactions; chemical structure; color; fluorescence; schiff bases; zinc
Abstract:
... A C₃-symmetric Schiff-base example of the new simple, low cost, highly water soluble, and sensitive turn-on fluorescent Zn²⁺ chemosensor is described. The sensor was successfully applied to the detection of intracellular Zn²⁺. Moreover, the sensor could also serve as a potential recyclable component in sensing materials. Notably, the color change is so obvious that all of the recycling process can ...
DOI:
10.1021/ol2034417

16. A one-pot hydrothermal synthesis of sulfur and nitrogen doped carbon aerogels with enhanced electrocatalytic activity in the oxygen reduction reaction

Author:
Wohlgemuth, Stephanie-Angelika; White, Robin Jeremy; Willinger, Marc-Georg; Titirici, Maria-Magdalena; Antonietti, Markus
Source:
Green chemistry 2012 v.14 no.5 pp. 1515-1523
ISSN:
1463-9270
Subject:
aerogels; carbon; catalysts; catalytic activity; electrochemistry; green chemistry; hydrothermal carbonization; nitrogen; pyrolysis; sulfur; synergism
Abstract:
... A one-pot, hydrothermal synthesis of nitrogen and sulfur dual doped carbon aerogels is presented, derived from our previously published hydrothermal carbonization approach. Two co-monomers, S-(2-thienyl)-l-cysteine (TC) and 2-thienyl carboxaldehyde (TCA), were used for sulfur incorporation, giving rise to distinct morphologies and varying doping levels of sulfur. Nitrogen-doping levels of 5 wt% an ...
DOI:
10.1039/c2gc35309a

17. A one-pot regioselective synthetic route to vinyl sulfones from terminal epoxides in aqueous media

Author:
Chawla, Ruchi; Kapoor, Ritu; Singh, Atul K.; Yadav, Lal Dhar S.
Source:
Green chemistry 2012 v.14 no.5 pp. 1308-1313
ISSN:
1463-9270
Subject:
catalysts; catalytic activity; epoxides; green chemistry; regioselectivity; sodium
Abstract:
... A highly efficient LiBr catalysed regioselective synthesis of vinyl sulfones from readily available terminal epoxides and sodium sulfinates in a one-pot procedure using water as a reaction medium is reported. The protocol is adorned with several attributes of green chemistry like recycling of the catalyst, atom-economy and an aqueous medium. ...
DOI:
10.1039/c2gc16664j

18. Argutalactone, an unprecedented sesquiterpenoid lactone with a 6/5/7 tricyclic system from Incarvillea arguta

Author:
Fu, Jian-Jun; Wang, Li-Yan; Li, Hong-Lin; Qin, Jiang-Jiang; Shen, Yun-Heng; Cheng, Jia-Gao; Jin, Hui-Zi; Zhang, Wei-Dong
Source:
Journal of Asian natural products research 2012 v.14 no.5 pp. 496-502
ISSN:
1477-2213
Subject:
Incarvillea; chemical structure; circular dichroism spectroscopy; roots; sesquiterpenoid lactones; spectral analysis
Abstract:
... Argutalactone (1), a novel sesquiterpenoid lactone featuring an unprecedented 6/5/7 rigid skeleton, was isolated from the roots of Incarvillea arguta. The structure and relative configuration of 1 were established by extensive analysis of spectroscopic data. The absolute configuration of 1 was determined as 2R,5S,10R,12S based on the analysis of biogenetical transformation, comparison of the optic ...
DOI:
10.1080/10286020.2012.668535

19. A selection platform for carbon chain elongation using the CoA-dependent pathway to produce linear higher alcohols

Author:
Machado, Hidevaldo B.; Dekishima, Yasumasa; Luo, Hao; Lan, Ethan I.; Liao, James C.
Source:
Metabolic engineering 2012 v.14 no.5 pp. 504-511
ISSN:
1096-7176
Subject:
Clostridium acetobutylicum; Cupriavidus necator; Escherichia coli; acids; acyl coenzyme A; beta oxidation; butanol; carbon; directed evolution; enzymes; feedstocks; fuels; metabolic engineering; mutagenesis
Abstract:
... Production of green chemicals and fuels using metabolically engineered organisms has been a promising alternative to petroleum-based production. Higher chain alcohols (C4–C8) are of interest because they can be used as chemical feedstock as well as fuels. Recently, the feasibility of n-hexanol synthesis using Escherichia coli has been demonstrated by extending the modified Clostridium CoA-dependen ...
DOI:
10.1016/j.ymben.2012.07.002

20. Asymmetric Synthesis of 4,8-Dihydroxyisochroman-1-one Polyketide Metabolites Using Chiral Hypervalent Iodine(III)

Author:
Fujita, Morifumi; Mori, Kazuhiro; Shimogaki, Mio; Sugimura, Takashi
Source:
Organic letters 2012 v.14 no.5 pp. 1294-1297
ISSN:
1523-7052
Subject:
chemical reactions; chemical structure; iodine; metabolites; polyketides; stereoselectivity
Abstract:
... Stereoselective oxylactonization of ortho-alkenylbenzoate with chiral hypervalent iodine is applied to the asymmetric synthesis of 4-oxyisochroman-1-one polyketide metabolites including 4-hydroxymellein (1), a derivative of fusarentin 2, monocerin (3), and an epimer of monocerin epi-3. ...
DOI:
10.1021/ol300185u