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Search for "template" in Full Text gives 195 result(s) in Beilstein Journal of Organic Chemistry.

The aminoindanol core as a key scaffold in bifunctional organocatalysts

  • Isaac G. Sonsona,
  • Eugenia Marqués-López and
  • Raquel P. Herrera

Beilstein J. Org. Chem. 2016, 12, 505–523, doi:10.3762/bjoc.12.50

Graphical Abstract
  • ). In the proposed transition state TS11, the α,β-unsaturated substrate is activated by an acidic thiourea template. Moreover, the hydroxylamine derivative is simultaneously oriented to attack the Si face of the Michel acceptor, through its interaction with the hydroxy group of the aminoindanol
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Published 14 Mar 2016

Polydisperse methyl β-cyclodextrin–epichlorohydrin polymers: variable contact time 13C CP-MAS solid-state NMR characterization

  • Isabelle Mallard,
  • Davy Baudelet,
  • Franca Castiglione,
  • Monica Ferro,
  • Walter Panzeri,
  • Enzio Ragg and
  • Andrea Mele

Beilstein J. Org. Chem. 2015, 11, 2785–2794, doi:10.3762/bjoc.11.299

Graphical Abstract
  • paper, we described the synthesis of imprinted polymers. The imprinting technique is based on interactions between a template and a suitable functional monomer during the prepolymerization process. Once the template is removed, the resulting product is a cross-linked copolymer matrix with specific
  • recognition sites for the template molecule. As a matter of fact, high-resolution solid-state NMR is a powerful tool to characterize the structure of polymers [23][24] and to study their dynamics [25][26]. Crini has reported previously a solid-state NMR spectroscopy study [27][28] of β-cyclodextrin polymers
  • template introduces highly specific sites into the polymeric network and, after removal of the target the polymer is able to rebind the molecule with high selectivity. Polymers of CRYSMEB were synthesized according to the procedure of Mallard Favier [22]. Our synthetic protocol was chosen to employ a
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Published 30 Dec 2015

Assembly of synthetic Aβ miniamyloids on polyol templates

  • Sebastian Nils Fischer and
  • Armin Geyer

Beilstein J. Org. Chem. 2015, 11, 2646–2653, doi:10.3762/bjoc.11.284

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  • , Aβ peptide pentapeptide boronic acids 1 and 2 were synthesized by solid-phase peptide synthesis and studied in esterification experiments with polyhydroxylated templates. The bis-hydroxylated dipeptide Hot=Tap serves as a template of adjustable degree of oligomerization which spontaneously forms
  • boronic esters with peptides of type 1 and 2. Nuclear magnetic resonance can differentiate between regioisomeric boronic esters and identifies preferred sites of esterification on the dimeric template 9. 2-Formylphenylboronic acid (14) is used to link the parent pentapeptide Leu-Val-Phe-Phe-Ala to the
  • template 16 to obtain threefold boronic ester 17. The miniamyloid 17 assembles from seven components by imine and boronic ester bonds between the peptides and the template. The relative orientation and spacing of the peptides mimic the assembly of peptides in Alzheimer β-amyloids. Keywords: Alzheimer
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Published 17 Dec 2015

Diversity-oriented synthesis of analogues of the novel macrocyclic peptide FR-225497 through late stage functionalization

  • Jyotiprasad Mukherjee,
  • Suman Sil and
  • Shital Kumar Chattopadhyay

Beilstein J. Org. Chem. 2015, 11, 2487–2492, doi:10.3762/bjoc.11.270

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  • [16][17] on a macrocyclic template would constitute a direct approach for grafting the pendant alkyl chain of 1, as demonstrated retrosynthetically in Figure 2. Our initial focus was on the preparation of analogues of the macrocyclic compound 4 through variation of the end groups as it has been shown
  • responsible for the increased activity of compound 4 compared to 2 or 3 [18]. Accommodating some of these common features, we prepared the macrocyclic template 13 (Scheme 1) through the acyclic tetrapeptide Boc-L-Bhag-L-Phe-L-Phe-D-Pro-OMe (11) (Bhag = bishomoallylglycine) [19]. The latter was accessed by
  • in readiness for a subsequent macrocyclization. The macrocyclization proceeded well under our previously developed conditions [21] to deliver the template 13 in an acceptable yield of 73% over two steps. We next focused our attention on the crucial cross metathesis reaction of 13. Attempted CM of 13
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Published 08 Dec 2015

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

  • Shintaro Kawano,
  • Toshiyuki Kida,
  • Mitsuru Akashi,
  • Hirofumi Sato,
  • Motohiro Shizuma and
  • Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

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  • complexes microparticles can be formed by an emulsion template and subsequent core oil removal. These previous works have been limited to preparing Pickering emulsions via the formation of CD–oil complexes at the oil–water interface. Thus, emulsion formation requires a high concentration of CDs and depends
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Published 30 Nov 2015

Synthesis of α,β-unsaturated esters via a chemo-enzymatic chain elongation approach by combining carboxylic acid reduction and Wittig reaction

  • Yitao Duan,
  • Peiyuan Yao,
  • Yuncheng Du,
  • Jinhui Feng,
  • Qiaqing Wu and
  • Dunming Zhu

Beilstein J. Org. Chem. 2015, 11, 2245–2251, doi:10.3762/bjoc.11.243

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  • Mycobacterium gDNA as template and primers containing the restriction sites NdeI and XhoI, respectively, CAR-F 5′-CATGCATATGTTCGCCGAAAATCTTGATGACCAG-3′ and CAR-R 5′-CATCTCGA GCAGCAGGCCGAGCAATTGCAGGT-3′. The PCR fragment was purified and then ligated with cloning vector pJET1.2/blunt, which was confirmed by DNA
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Published 19 Nov 2015

Supramolecular chemistry: from aromatic foldamers to solution-phase supramolecular organic frameworks

  • Zhan-Ting Li

Beilstein J. Org. Chem. 2015, 11, 2057–2071, doi:10.3762/bjoc.11.222

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  • core [11]. Using this method, I could prepare bimacrocycle 3 in a short time. This macrocycle was used to template the formation of the so-called tetracationic “blue box” [12][13] from 4 and 5 to give rise to the unique pseudo[3]catenanes 6a and 6b (Scheme 2), together with a trace amount of [2
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Published 02 Nov 2015

Lewis acid-promoted hydrofluorination of alkynyl sulfides to generate α-fluorovinyl thioethers

  • Davide Bello and
  • David O'Hagan

Beilstein J. Org. Chem. 2015, 11, 1902–1909, doi:10.3762/bjoc.11.205

Graphical Abstract
  • functional and complementary template in enzymatic DNA synthesis [6]. We have recently begun to explore synthesis methods to prepare α-fluorovinyl thioethers, to open up the possibility of exploring this motif as a mimetic for enols and enolates of biochemically relevant thioesters. Thioesters of low
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Published 14 Oct 2015

Engineering Pichia pastoris for improved NADH regeneration: A novel chassis strain for whole-cell catalysis

  • Martina Geier,
  • Christoph Brandner,
  • Gernot A. Strohmeier,
  • Mélanie Hall,
  • Franz S. Hartner and
  • Anton Glieder

Beilstein J. Org. Chem. 2015, 11, 1741–1748, doi:10.3762/bjoc.11.190

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  • the transformation of P. pastoris CBS7435 wild type cells according to the condensed protocol by Lin-Cereghino et al. [23]. Transformants were selected on YPD agar plates containing 100 mg/L ZeocinTM. The correct integration of the knock-out cassette was confirmed by PCR using genomic DNA as template
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Published 25 Sep 2015

Active site diversification of P450cam with indole generates catalysts for benzylic oxidation reactions

  • Paul P. Kelly,
  • Anja Eichler,
  • Susanne Herter,
  • David C. Kranz,
  • Nicholas J. Turner and
  • Sabine L. Flitsch

Beilstein J. Org. Chem. 2015, 11, 1713–1720, doi:10.3762/bjoc.11.186

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  • -RhFRed could be used as a template for engineering variants for the stereoselective benzylic hydroxylation of substituted aromatics 5–8. Results and Discussion Introducing structural and functional diversity into P450cam The P450cam-RhFRed libraries were generated by targeting 12 active site residues
  • . Based on previous studies [10][11], the Tyr96Phe variant of P450cam was chosen as the template for screen development and subsequent mutagenesis. Thus, ≈16,500 colonies containing P450cam[Tyr96Phe]-RhFRed variants were rapidly screened for indigo formation (Figure 1, right), from which 93 new variants
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Published 22 Sep 2015

A novel and widespread class of ketosynthase is responsible for the head-to-head condensation of two acyl moieties in bacterial pyrone biosynthesis

  • Darko Kresovic,
  • Florence Schempp,
  • Zakaria Cheikh-Ali and
  • Helge B. Bode

Beilstein J. Org. Chem. 2015, 11, 1412–1417, doi:10.3762/bjoc.11.152

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  • could be obtained due to low expression levels under all conditions tested. The homodimeric structure of OleA from Xanthomonas campestris, showing the highest sequence identity (27%) of all available crystal structures at the PDB [21], was used as a template. OleA is responsible for the head-to-head
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Published 12 Aug 2015

Selected synthetic strategies to cyclophanes

  • Sambasivarao Kotha,
  • Mukesh E. Shirbhate and
  • Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

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  • cyclophanes by using a template-promoted cyclization involving the RCM as a key step. This approach proceeded via the condensation of compound 191 with acenaphthenequinone in the presence of p-TSA to deliver the RCM precursor 192, which facilitate the cyclization protocol with G-II (13) as a catalyst to
  • generate cyclophane derivative 193 containing an α-diimine functionality. Subsequently, the hydrogenation of 193 gave cyclophane 195. The removal of the template under hydrogenolytic conditions gave the macrocyclic compound 194 (Scheme 31). In continuation of earlier work [145], Kotha and co-workers have
  • and nanomaterials is a challenging task. Huang and co-workers [165] have reported a taco complex template method to synthesize a cryptand/paraquat [2]rotaxane and [2]catenane (e.g., 207) by using RCM as a key step. Structural features and interesting bioactivity of the hirsutellones have grabbed the
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Published 29 Jul 2015

A new and efficient procedure for the synthesis of hexahydropyrimidine-fused 1,4-naphthoquinones

  • Marcelo Isidoro P. Reis,
  • Vinícius R. Campos,
  • Jackson A. L. C. Resende,
  • Fernando C. Silva and
  • Vitor F. Ferreira

Beilstein J. Org. Chem. 2015, 11, 1235–1240, doi:10.3762/bjoc.11.137

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  • 1,3,5-triazinanes and products were confirmed by spectroscopical methods and X-ray diffraction analysis. General template for heterocycle-fused 1,4-naphthoquinones. ORTEP diagram of compound 18 depicted with ellipsoids drawn at the 50% probability level and the atom-numbering scheme. ORTEP diagram of
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Published 22 Jul 2015

Azobenzene-based inhibitors of human carbonic anhydrase II

  • Leander Simon Runtsch,
  • David Michael Barber,
  • Peter Mayer,
  • Michael Groll,
  • Dirk Trauner and
  • Johannes Broichhagen

Beilstein J. Org. Chem. 2015, 11, 1129–1135, doi:10.3762/bjoc.11.127

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  • . Furthermore, the protein crystal structure of hCAII bound to 1d described herein can be used as a template for the rational design of novel hCAII blockers. The biological activity of these blockers is currently under investigation and the results will be published in due course. Function and inhibition of
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Published 07 Jul 2015

Mechanical stability of bivalent transition metal complexes analyzed by single-molecule force spectroscopy

  • Manuel Gensler,
  • Christian Eidamshaus,
  • Maurice Taszarek,
  • Hans-Ulrich Reissig and
  • Jürgen P. Rabe

Beilstein J. Org. Chem. 2015, 11, 817–827, doi:10.3762/bjoc.11.91

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  • °C). 1H NMR (CDCl3, 700 MHz) δ 6.81 (dd, J = 4.8, 1.5 Hz, 4H, 3-H, 5-H), 8.43 (dd, J = 4.8, 1.5 Hz, 4H, 2-H, 6-H) ppm. Surface films of the polymers were prepared in a similar manner as described before [27]. A droplet of a 1 mM aqueous polymer solution was applied to freshly template-stripped gold
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Published 15 May 2015

Discrete multiporphyrin pseudorotaxane assemblies from di- and tetravalent porphyrin building blocks

  • Mirko Lohse,
  • Larissa K. S. von Krbek,
  • Sebastian Radunz,
  • Suresh Moorthy,
  • Christoph A. Schalley and
  • Stefan Hecht

Beilstein J. Org. Chem. 2015, 11, 748–762, doi:10.3762/bjoc.11.85

Graphical Abstract
  • only contributes to binding enhancement, but also helps to exert control over complex formation. For example, “molecular elevators” have been constructed by Stoddart et al. [30][31] and giant porphyrin wheels were prepared by Anderson and co-workers [32][33], both using a multivalent template strategy
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Published 12 May 2015

DNA display of glycoconjugates to emulate oligomeric interactions of glycans

  • Alexandre Novoa and
  • Nicolas Winssinger

Beilstein J. Org. Chem. 2015, 11, 707–719, doi:10.3762/bjoc.11.81

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  • hybridization instructions (Figure 1). This hybridization can be used to rigidify a nucleic acid strand containing multiple glycans at variable positions, to generate oligomers through half-slide hybridization and to combinatorial pair multiple ligands. The flexibility of the template can be further tuned with
  • by Seitz and co-workers using thiols imbedded in the backbone of the PNA that were chemoselectively conjugated to a maleimide–glycan adduct [43]. Our first efforts in the area of glycan display aimed to demonstrate that a DNA template could be used to program the assembly of discrete PNA-tagged
  • ligands in order to recapitulate the geometry of HIV’s gp120 glycan epitope which is composed of multiple copies of a high mannose undecasaccharide [38]. An advantage of displaying ligands through template assembly of discrete units is that the pairing and distance can be controlled though the template
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Published 11 May 2015

Morita–Baylis–Hillman reaction of acrylamide with isatin derivatives

  • Radhey M. Singh,
  • Kishor Chandra Bharadwaj and
  • Dharmendra Kumar Tiwari

Beilstein J. Org. Chem. 2014, 10, 2975–2980, doi:10.3762/bjoc.10.315

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  • been the favored template not only for the spectrum of biological activities it provides, but also with respect to the development of methodologies [33]. In the field of MBH, it has been used both for reaction development [34][35][36][37][38][39] and application of its MBH-derived adduct [40][41][42
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Published 12 Dec 2014

Mono- and multilayers of molecular spoked carbazole wheels on graphite

  • Stefan-S. Jester,
  • A. Vikas Aggarwal,
  • Daniel Kalle and
  • Sigurd Höger

Beilstein J. Org. Chem. 2014, 10, 2783–2788, doi:10.3762/bjoc.10.295

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  • behave as more or less rigid objects of certain sizes and shapes – depending on their chemical structures. In addition, the images provide insight into the multilayer growth of the molecular spoked wheels (MSWs), where the first adlayer acts as a template for the commensurate adsorption of molecules in
  • the second layer. Keywords: molecular spoked wheels; scanning tunneling microscopy; self-assembled monolayers; solid/liquid interface; template; Introduction Molecular spoked wheels (MSWs) have gained increasing interest as two-dimensional (2D) carbon-based objects of adjustable sizes [1][2][3][4][5
  • ]. These represent basic building blocks for a supramolecular Archimedean surface tessellation system [9]. Thereby, the highly oriented pyrolytic graphite (HOPG) acts as a template along the main axis directions of which the alkyl/alkoxy side chains align [10][11], and consequently the superstructures can
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Published 27 Nov 2014

Self-assembled monolayers of shape-persistent macrocycles on graphite: interior design and conformational polymorphism

  • Joscha Vollmeyer,
  • Friederike Eberhagen,
  • Sigurd Höger and
  • Stefan-S. Jester

Beilstein J. Org. Chem. 2014, 10, 2774–2782, doi:10.3762/bjoc.10.294

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  • macrocycle distances are mainly determined by their size and symmetry. This is an excellent example that the graphite acts as a template for the macrocycle organization independent from their specific interior. Keywords: conformational polymorphism; self-assembled monolayers; shape-persistent macrocycles
  • ; solid/liquid interface; supramolecular surface patterning; template; Introduction One of the ultimate aims in supramolecular chemistry on solid surfaces is the formation of two-dimensional (2D) nanostructures that are capable of performing highly specific tasks as an effect of functional units that are
  • analogs) that guarantee a sufficient compound solubility. The macrocycles can be co-assembled with other compounds at the surface [3][4], and they can also template the subsequent organization of guest molecules and thus a growth into the third dimension [5][6]. One of the most often used substrates for
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Published 26 Nov 2014

Autonomous assembly of synthetic oligonucleotides built from an expanded DNA alphabet. Total synthesis of a gene encoding kanamycin resistance

  • Kristen K. Merritt,
  • Kevin M. Bradley,
  • Daniel Hutter,
  • Mariko F. Matsuura,
  • Diane J. Rowold and
  • Steven A. Benner

Beilstein J. Org. Chem. 2014, 10, 2348–2360, doi:10.3762/bjoc.10.245

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  • complement 2’-deoxyisoguanosine (trivially designated B) (Figure 2) are used to assemble a L-DNA construct, the S:B pair forms orthogonally to the T:A and C:G pairs [18][19]. However, if dSTP is missing during primer extension, B in a template must be mismatched during primer extension. Here, conversion
  • shown in Figure 3. Two conditions were tested for the conversion PCR. The first included a small amount of 2’-d-isoGTP (dBTP, ChemGenes, 0.3 µL of a 10 mM stock, 3 nmol per assay, final concentration 60 µM) to complement the 2’-d-isoC in the template. In the presence of dBTP, the conversion requires two
  • cycles. In the first, dBTP is incorporated opposite template dS, while dTTP is mismatched opposite template dB, presumably via its minor tautomer. In the second cycle, conversion is completed by mismatching dT opposite the minor enol dB in the newly synthesized template (Figure 3). Thus, the use of dBTP
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Published 09 Oct 2014

Molecular ordering at electrified interfaces: Template and potential effects

  • Thanh Hai Phan and
  • Klaus Wandelt

Beilstein J. Org. Chem. 2014, 10, 2243–2254, doi:10.3762/bjoc.10.233

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  • mechanism. Comparison of both observed structures with those found earlier at different electrode potentials on a c(2 × 2)Cl-precovered Cu(100) electrode surface enables a clear assessment of the relative importance of adsorbate–substrate and adsorbate–adsorbate interactions, i.e., template vs self-assembly
  • effects, in the structure formation process of DBV cations on these modified Cu electrode surfaces. Keywords: cyclic voltammogram; scanning tunneling microscopy; self-assembly; template effect; viologen; Introduction The precise control of the self-organization of molecular layers on either conducting
  • , provided a sufficient surface mobility allows the adsorbed molecules to reach their equilibrium positions, i.e., minima in the corrugation function. In this case the substrate surface acts as a “template”. Under UHV conditions the activation energy for structural equilibration is usually provided by
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Published 23 Sep 2014

Lateral ordering of PTCDA on the clean and the oxygen pre-covered Cu(100) surface investigated by scanning tunneling microscopy and low energy electron diffraction

  • Stefan Gärtner,
  • Benjamin Fiedler,
  • Oliver Bauer,
  • Antonela Marele and
  • Moritz M. Sokolowski

Beilstein J. Org. Chem. 2014, 10, 2055–2064, doi:10.3762/bjoc.10.213

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  • to that of PTCDA bulk lattice planes. Keywords: Cu(100); LEED; PTCDA; STM; template; thin organic films; Introduction Interfaces between organic semiconductors and metals have gained large interest because they are present in many applications, e.g., organic field-effect transistors [1] or organic
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Published 01 Sep 2014

A new charge-tagged proline-based organocatalyst for mechanistic studies using electrospray mass spectrometry

  • J. Alexander Willms,
  • Rita Beel,
  • Martin L. Schmidt,
  • Christian Mundt and
  • Marianne Engeser

Beilstein J. Org. Chem. 2014, 10, 2027–2037, doi:10.3762/bjoc.10.211

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  • temporal evolution has been followed using a microreactor continuous-flow technique. Keywords: charge tag; electrospray; mass spectrometry; organocatalysis; proline; template; Introduction Electrospray ionization (ESI) mass spectrometry [1] has not only developed into a standard characterization method
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Published 28 Aug 2014

Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules

  • Thilo Focken and
  • Stephen Hanessian

Beilstein J. Org. Chem. 2014, 10, 1848–1877, doi:10.3762/bjoc.10.195

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  • template for the stereocontrolled incorporation of the remaining stereocenters. The construction of butenolide 83 started from (R)-citronellol (84), which could in principle, deliver the entire alkenyl side chain of acetoxycrenulide (10) (Scheme 11). However, the double bond needed to be transformed into a
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Published 13 Aug 2014
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