Synthetic strategies for the fluorescent labeling of epichlorohydrin-branched cyclodextrin polymers

• Milo Malanga,
• Mihály Bálint,
• István Puskás,
• Kata Tuza,
• Tamás Sohajda,
• László Jicsinszky,
• Lajos Szente and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2014, 10, 3007–3018, doi:10.3762/bjoc.10.319

• either by branching the proper cyclodextrin derivatives (pre-branching modification) or by derivatization of the cyclodextrin polymers (post-branching modification). Several examples of both modification types of these macromolecules with additional groups are reported in the literature [5] and an update

Synthesis of uniform cyclodextrin thioethers to transport hydrophobic drugs

• Lisa F. Becker,
• Dennis H. Schwarz and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 2920–2927, doi:10.3762/bjoc.10.310

• anaesthesia. Keywords: active pharmaceutical ingredient; binding constant; cyclodextrin; derivatization; gas chromatography; sevoflurane; substitution pattern; Introduction Cyclodextrins (CDs) are cyclic oligomers of α-1,4-linked glucose units. Those CDs consisting of 6, 7, and 8 glucose units are called α

Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

• Daniel I. Hădărugă,
• Nicoleta G. Hădărugă,
• Corina I. Costescu,
• Ioan David and
• Alexandra T. Gruia

Beilstein J. Org. Chem. 2014, 10, 2809–2820, doi:10.3762/bjoc.10.298

• the corresponding biologically active compounds. These were used as raw mixtures (e.g., extracts for food supplements), as well as purified bioactive compounds for the treatment of various diseases. They were used in natural form or after derivatization to a more bioactive compound, such as the

Galactan synthesis in a single step via oligomerization of monosaccharides

• Marius Dräger and
• Amit Basu

Beilstein J. Org. Chem. 2014, 10, 2658–2663, doi:10.3762/bjoc.10.279

• , Table 2, entry 5), followed by derivatization of the products as the TBS ethers, isolable quantities of the pentasaccharide 155c were generated. Secondary alcohols such as cyclohexanol or the sterically more hindered menthol successfully underwent glycosylation to provide mono- and disaccharides, but

Formal total syntheses of classic natural product target molecules via palladium-catalyzed enantioselective alkylation

• Yiyang Liu,
• Marc Liniger,
• Ryan M. McFadden,
• Jenny L. Roizen,
• Jacquie Malette,
• Corey M. Reeves,
• Douglas C. Behenna,
• Masaki Seto,
• Jimin Kim,
• Justin T. Mohr,
• Scott C. Virgil and
• Brian M. Stoltz

Beilstein J. Org. Chem. 2014, 10, 2501–2512, doi:10.3762/bjoc.10.261

• enantiomeric to the intermediate employed by Pandey in the synthesis of (+)-vincadifformine. Conclusion The development of a series of Pd-catalyzed methods for constructing stereogenic quaternary carbons has provided two generations of building blocks (Scheme 16). The described derivatization enabled the

A small azide-modified thiazole-based reporter molecule for fluorescence and mass spectrometric detection

• Stefanie Wolfram,
• Hendryk Würfel,
• Stefanie H. Habenicht,
• Christine Lembke,
• Phillipp Richter,
• Eckhard Birckner,
• Rainer Beckert and
• Georg Pohnert

Beilstein J. Org. Chem. 2014, 10, 2470–2479, doi:10.3762/bjoc.10.258

• . Derivatization with dansyl chloride is used for labeling of primary and secondary amines or phenols resulting in enhanced ESI signals and shifted retention times of labeled polar analytes in reversed-phase LC [27]. For comparison with BPT (1) we also introduced bromine into the aromatic system of DNS (8) to

• which ensures solubility of BPT (1). UPLC–ESIMS measurements were employed to characterize ionization properties of the fluorophores (Figure 5B). In positive mode BPT (1) gives a slightly higher peak area than DNS (8). Derivatization with dansyl chloride has been previously introduced as an ionization

Reversibly locked thionucleobase pairs in DNA to study base flipping enzymes

• Christine Beuck and
• Elmar Weinhold

Beilstein J. Org. Chem. 2014, 10, 2293–2306, doi:10.3762/bjoc.10.239

• large number of modified building blocks, also suitable for further post-synthetic derivatization, is commercially available and allows a convenient access to modified ODN. Several protocols to generate selective DNA interstrand cross-links in short duplex ODN have been described, however, most of them

Derivatives of the triaminoguanidinium ion, 3. Multiple N-functionalization of the triaminoguanidinium ion with isocyanates and isothiocyanates

• Jan Szabo,
• Kerstin Karger,
• Nicolas Bucher and
• Gerhard Maas

Beilstein J. Org. Chem. 2014, 10, 2255–2262, doi:10.3762/bjoc.10.234

• coordination architectures in the solid state. TAG-Cl (1) was first prepared from carbon tetrachloride and hydrazine by R. Stollé in the year 1904 [7], but it was not until half a century later that some interest in its chemistry emerged. Derivatization reactions with aldehydes and ketones furnished tris

Chiral phosphines in nucleophilic organocatalysis

• Yumei Xiao,
• Zhanhu Sun,
• Hongchao Guo and
• Ohyun Kwon

Beilstein J. Org. Chem. 2014, 10, 2089–2121, doi:10.3762/bjoc.10.218

• conditions. The obtained products could be transformed smoothly into many complex and potentially useful compounds, through diverse derivatization, without significant losses of enantiomeric excesses. 2.13 Annulations through tandem RC/Michael reactions In 2012, using the chiral threonine-derived phosphine

Synthesis of a bifunctional cytidine derivative and its conjugation to RNA for in vitro selection of a cytidine deaminase ribozyme

• Nico Rublack and
• Sabine Müller

Beilstein J. Org. Chem. 2014, 10, 1906–1913, doi:10.3762/bjoc.10.198

• reactant merely to the 5'-terminus of library RNAs [15][16][17]. Alternatively, post-transcriptional protocols can address both the 5'- and the 3'-terminus. In general, post-transcriptional 5'-modification may be achieved by thiophosphorylation with T4-polynucleotide kinase followed by derivatization of

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

Sacrolide A, a new antimicrobial and cytotoxic oxylipin macrolide from the edible cyanobacterium Aphanothece sacrum

• Naoya Oku,
• Miyako Matsumoto,
• Kohsuke Yonejima,
• Keijiroh Tansei and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2014, 10, 1808–1816, doi:10.3762/bjoc.10.190

• . Initial derivatization strategy for the stereochemical analysis of sacrolide A (1). Determination of the stereochemistry of sacrolide A (1). Plausible biosynthesis of sacrolide A (1). 1H (500 MHz) and 13C (125 MHz) NMR data for sacrolide A (1) in CDCl3 (δ in ppm). Antimicrobial activity of sacrolide A (1

• ). Supporting Information Supporting Information File 656: Procedures for chemical conversion/derivatization, NMR assignments, copies of NMR, MS and UV spectra for 1, NMR spectra for 2, 3, 3a and 3b. Acknowledgements This work was supported in part by the President’s Fund Initiative at the Toyama Prefectural

One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular S_N2 reaction

• Yiwen Xiong,
• Ping Qian,
• Chenhui Cao,
• Haibo Mei,
• Jianlin Han,
• Guigen Li and
• Yi Pan

Beilstein J. Org. Chem. 2014, 10, 1802–1807, doi:10.3762/bjoc.10.189

• to the previous reports on the derivatization of aminohalogenation reactions, the vicinal haloamines usually underwent elimination or aziridination reactions when they were treated with organic bases (Scheme 2) [33][34][35]. However, when benzylamine was added to haloamine 1a in acetonitrile, the

Carbohydrate PEGylation, an approach to improve pharmacological potency

• M. Eugenia Giorgi,
• Rosalía Agusti and
• Rosa M. de Lederkremer

Beilstein J. Org. Chem. 2014, 10, 1433–1444, doi:10.3762/bjoc.10.147

• identification of signals that disappear or are shifted when conjugation takes place, together with the appearance of new signals due to the sugar in well-separated regions of the spectrum are used to confirm the extent of derivatization of the multiarm PEGs. PEGylation of polysaccharides: PEGylation of chitosan

• particular, multiarm PEGylation with more available sites for glycan linking can be exploited for improvement of interaction of carbohydrates with cell receptors. We hope that this review on sugar PEGylation will provoke further studies on the subject. Types of PEG utilized for derivatization of drugs and

A complete series of 6-deoxy-monosubstituted tetraalkylammonium derivatives of α-, β-, and γ-cyclodextrin with 1, 2, and 3 permanent positive charges

• Martin Popr,
• Simona Hybelbauerová and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2014, 10, 1390–1396, doi:10.3762/bjoc.10.142

• function Analogues of PEMEDA and PEMPDA-β-CD with an azidoethane function attached to the terminal quaternary ammonium nitrogen were prepared as a basis for further derivatization. The azide functional group is reactive and can be used, for example, for the attachment of various substituted acetylenes by a

Stereoselective synthesis of carbocyclic analogues of the nucleoside Q precursor (PreQ₀)

• Sabin Llona-Minguez and
• Simon P. Mackay

Beilstein J. Org. Chem. 2014, 10, 1333–1338, doi:10.3762/bjoc.10.135

• -phenylcyclohexanamines, although with poor diastereomeric control [37][38]. 1-Cyclohex-2-enone provided the two required synthetic handles: a sp2 carbon for Pd chemistry and a ketone for further derivatization into an amine group (Figure 6). The synthesis of cis- and trans-3-arylcyclohexylamines 23 and 24 started with a

Synthesis, characterization and DNA interaction studies of new triptycene derivatives

• Sourav Chakraborty,
• Snehasish Mondal,
• Rina Kumari,
• Sourav Bhowmick,
• Prolay Das and
• Neeladri Das

Beilstein J. Org. Chem. 2014, 10, 1290–1298, doi:10.3762/bjoc.10.130

• . Subsequently, derivatization of ethynyl-substituted triptycenes was studied to yield the respective propiolic acid and ethynylphosphine derivatives. Characterization of the newly functionalized triptycene derivatives and their regioisomers were carried out using FTIR and multinuclear NMR spectroscopy, mass

Automated solid-phase peptide synthesis to obtain therapeutic peptides

• Veronika Mäde,
• Sylvia Els-Heindl and
• Annette G. Beck-Sickinger

Beilstein J. Org. Chem. 2014, 10, 1197–1212, doi:10.3762/bjoc.10.118

• , selective derivatization is described for neuropeptide Y (NPY) receptor ligands for therapeutical and analytical applications. Modifications of therapeutic peptides to extend their half-lifes As summarized in Table 1, natural peptides suffer from fast proteolytic degradation and body clearance. Furthermore

Atherton–Todd reaction: mechanism, scope and applications

• Stéphanie S. Le Corre,
• Mathieu Berchel,
• Hélène Couthon-Gourvès,
• Jean-Pierre Haelters and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2014, 10, 1166–1196, doi:10.3762/bjoc.10.117

• determination of the enantiomeric excess of a chiral amine based on the use of phosphorinanes derivatives. Two synthetic pathways i) the AT reaction and ii) the direct use of chlorophosphate were evaluated for the derivatization of chiral amine (or alcohol) as reported in Scheme 6. For the AT reaction (i) [23

Amino acid motifs in natural products: synthesis of O-acylated derivatives of (2S,3S)-3-hydroxyleucine

• Oliver Ries,
• Martin Büschleb,
• Markus Granitzka,
• Dietmar Stalke and
• Christian Ducho

Beilstein J. Org. Chem. 2014, 10, 1135–1142, doi:10.3762/bjoc.10.113

• derivatization as well as for solid-phase peptide synthesis. With respect to according motifs occurring in natural products, we have converted these building blocks into 3-O-acylated structures. Utilizing an esterification and cross-metathesis protocol, (2S,3S)-3-hydroxyleucine derivatives were synthesized, thus

• their route. In addition, we also envisaged to establish a facile strategy to introduce structural diversity in the O-acyl moiety, ideally by the late-stage derivatization of an according precursor. Results and Discussion Utilizing the aforementioned synthetic strategy developed by Zhu and co-workers

• harsh reaction conditions though (conc. HCl, reflux, 40 h) and yielded the unprotected amino acid as the hydrochloric salt. However, in the case of our envisaged synthesis of 3-hydroxyleucine building blocks suitable for further derivatization as well as incorporation into natural products and their

Site-selective covalent functionalization at interior carbon atoms and on the rim of circumtrindene, a C₃₆H₁₂ open geodesic polyarene

• Hee Yeon Cho,
• Ronald B. M. Ansems and
• Lawrence T. Scott

Beilstein J. Org. Chem. 2014, 10, 956–968, doi:10.3762/bjoc.10.94

• many examples of covalent chemistry for fullerenes (i.e., closed geodesic polyarenes), covalent functionalizations of open geodesic polyarenes other than corannulene have been reported only rarely. As in fullerene chemistry, chemical derivatization of buckybowls can be expected to change the electronic

Structure elucidation of female-specific volatiles released by the parasitoid wasp Trichogramma turkestanica (Hymenoptera: Trichogrammatidae)

• Armin Tröger,
• Teris A. van Beek,
• Martinus E. Huigens,
• Isabel M. M. S. Silva,
• Maarten A. Posthumus and
• Wittko Francke

Beilstein J. Org. Chem. 2014, 10, 767–773, doi:10.3762/bjoc.10.72

• – which would be avoided by a shift of the methyl group from carbon 2 to positions 4 or 5. Results of derivatization reactions of the natural product by Diels–Alder reaction with 4-methyl-1,2,4-triazolin-3,5-dione left room for the positioning of a methyl group at carbons 2, 3, 4, or 5 of the chain [12

Thermodynamically stable [4 + 2] cycloadducts of lanthanum-encapsulated endohedral metallofullerenes

• Yuta Takano,
• Yuki Nagashima,
• M. Ángeles Herranz,
• Nazario Martín and
• Takeshi Akasaka

Beilstein J. Org. Chem. 2014, 10, 714–721, doi:10.3762/bjoc.10.65

• production of any organic or inorganic byproduct [12][13]. Here, we present the first chemical derivatization of La2@C80 and La@C82 by [4 + 2] cycloaddition using sultines 1a,b. The resulting products 3a,b, 4a,b and 5b were characterized and their thermodynamic properties were investigated. Results and

Polyglycerol-functionalized nanodiamond as a platform for gene delivery: Derivatization, characterization, and hybridization with DNA

• Li Zhao,
• Yuki Nakae,
• Hongmei Qin,
• Tadamasa Ito,
• Takahide Kimura,
• Hideto Kojima,
• Lawrence Chan and
• Naoki Komatsu

Beilstein J. Org. Chem. 2014, 10, 707–713, doi:10.3762/bjoc.10.64

• multistep organic transformations including click chemistry. The PG layer on ND gave good aqueous dispersibility, enabling derivatization and characterization in the solution phase. The ND-PG-Arg8 and ND-PG-Lys8 possessing relatively high positive zeta potential immobilized the pDNA, demonstrating their

Copper–phenanthroline catalysts for regioselective synthesis of pyrrolo[3′,4′:3,4]pyrrolo[1,2-a]furoquinolines/phenanthrolines and of pyrrolo[1,2-a]phenanthrolines under mild conditions

• Rupankar Paira,
• Tarique Anwar,
• Maitreyee Banerjee,
• Yogesh P. Bharitkar,
• Shyamal Mondal,
• Sandip Kundu,
• Abhijit Hazra,
• Prakas R. Maulik and
• Nirup B. Mondal

Beilstein J. Org. Chem. 2014, 10, 692–700, doi:10.3762/bjoc.10.62

• encouraged us for further modification and derivatization of furoquinoline analogues in search for more potent agents. Thus we became interested in the construction of a number of structurally complex pentacyclic pyrrolo[3′,4′:3,4]pyrrolo[1,2-a]furoquinolines, for possible identification of new antibacterial