Design of a novel tryptophan-rich membrane-active antimicrobial peptide from the membrane-proximal region of the HIV glycoprotein, gp41

• Evan F. Haney,
• Leonard T. Nguyen,
• David J. Schibli and
• Hans J. Vogel

Beilstein J. Org. Chem. 2012, 8, 1172–1184, doi:10.3762/bjoc.8.130

• that membrane binding may be a part of a more complex mode of action involving multiple targets of inhibition [21][25]. In addition to their membrane-binding properties, many AMPs are typified by a high proportion of Trp and cationic amino acids [5][6]. The Trp residues are unique because of their

Synthesis of fluorinated maltose derivatives for monitoring protein interaction by ¹⁹F NMR

• Michaela Braitsch,
• Hanspeter Kählig,
• Georg Kontaxis,
• Michael Fischer,
• Toshinari Kawada,
• Robert Konrat and
• Walther Schmid

Beilstein J. Org. Chem. 2012, 8, 448–455, doi:10.3762/bjoc.8.51

• fluorination with DAST [34][35] yielded a mixture of fluorinated disaccharides: The desired product 22 [39] was isolated by column chromatography and Zemplén deprotection yielded derivative 23. Binding studies using the 2-F-maltose reporter system The binding properties of the two stereoisomers of 2-19F

A ferrocene redox-active triazolium macrocycle that binds and senses chloride

• Nicholas G. White and
• Paul D. Beer

Beilstein J. Org. Chem. 2012, 8, 246–252, doi:10.3762/bjoc.8.25

• triazole N-acceptors on adjacent molecules. Anion-binding investigations The anion-binding properties of 5·2PF6 were investigated in CD3CN solution by 1H NMR titration experiments. Aliquots of anions as their N-tetrabutylammonium (TBA) salts were added to 5·2PF6 and the chemical shift of the (chemically

Synthesis of multivalent host and guest molecules for the construction of multithreaded diamide pseudorotaxanes

• Nora L. Löw,
• Egor V. Dzyuba,
• Boris Brusilowskij,
• Lena Kaufmann,
• Elisa Franzmann,
• Wolfgang Maison,
• Emily Brandt,
• Daniel Aicher,
• Arno Wiehe and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2012, 8, 234–245, doi:10.3762/bjoc.8.24

• respect to their binding properties. Among the examples of such multivalent pseudorotaxanes [80][81][82], the “molecular elevators” reported by Stoddart et al. [83][84] are particularly fascinating, because they combine multivalency with the ability of a molecular device to respond to external stimuli, in

• )-, (trans,cis)- and (cis,cis)-isomers in solution, which complicates the analysis of the binding properties. Synthesis of multivalent wheels Monovalent axle 2 and TLM 1 are designed to give a good complementary fit, when both are connected to the same flat spacer molecules through Sonogashira cross-coupling

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• complex. 4.2 Binding properties of oxacalix[3]arene derivatives One of the most important features of calixarenes in general and oxacalix[3]arenes in particular is their vast ability to selectively bind and carry ions and neutral species. This is achieved mainly with lower-rim derivatives in solution

• sites, such as the carbonyl group, strongly affects the binding ability of calixarene derivatives. Thus, the binding properties of derivatives containing esters, amides and ketones, have been assessed. Extraction studies performed under the same conditions as described above reported that cone ester 12a

• selectivity for Na+ (50 and 20% E for 17a and 24, respectively) and 17a is also a good extractant for Ba2+ (55% E). Derivatives with heteroatoms on the lower rim have also been tested as cation chelators. The binding properties of 2-pyridylmethyloxy derivative 11a in both conformations, have been established

Binding of group 15 and group 16 oxides by a concave host containing an isophthalamide unit

• Jens Eckelmann,
• Vittorio Saggiomo,
• Svenja Fischmann and
• Ulrich Lüning

Beilstein J. Org. Chem. 2012, 8, 11–17, doi:10.3762/bjoc.8.2

• increased with respect to the non-preorganized isophthalamides. However, an intramolecular hydrogen bond can be easily broken in polar solvents, hence destroying the preorganization and thus decreasing the binding affinities for the anions. Herein we describe the facile synthesis and the binding properties

• ][14][15]. The preorganization and the exact shape of the “lampshade” determine the selectivity and the difference in binding of various guests. Results and Discussion Synthesis Besides the desired bi-macrocycle 1, isophthalamide 2 was synthesized in order to compare the binding properties of a non

(How) does 1,3,5-triethylbenzene scaffolding work? Analyzing the abilities of 1,3,5-triethylbenzene- and 1,3,5-trimethylbenzene-based scaffolds to preorganize the binding elements of supramolecular hosts and to improve binding of targets

• Xing Wang and
• Fraser Hof

Beilstein J. Org. Chem. 2012, 8, 1–10, doi:10.3762/bjoc.8.1

• 1,3,5-triethylbenzene (1Et) and 1,3,5-trimethylbenzene (1Me) templates in a single system is very rare (see below), which raises some questions: To what extent do ethyl substituents improve the binding properties of a host? To what extent do methyl substituents improve the binding properties of a host

Highly efficient cyclosarin degradation mediated by a β-cyclodextrin derivative containing an oxime-derived substituent

• Michael Zengerle,
• Florian Brandhuber,
• Christian Schneider,
• Franz Worek,
• Georg Reiter and
• Stefan Kubik

Beilstein J. Org. Chem. 2011, 7, 1543–1554, doi:10.3762/bjoc.7.182

• binding properties, and their relatively straightforward chemical modification have made cyclodextrins indispensable tools in applications such as sensing [2], nanotechnology [3][4], polymer chemistry [5][6][7][8], medicinal chemistry [9][10], food chemistry [11], and others. Importantly, the scope of

Fluorometric recognition of both dihydrogen phosphate and iodide by a new flexible anthracene linked benzimidazolium-based receptor

• Kumaresh Ghosh and
• Debasis Kar

Beilstein J. Org. Chem. 2011, 7, 254–264, doi:10.3762/bjoc.7.34

• Kumaresh Ghosh Debasis Kar Department of Chemistry, University of Kalyani, Kalyani-741235, India 10.3762/bjoc.7.34 Abstract A new flexible anthracene linked benzimidazolium-based receptor 1 has been designed, synthesized and its binding properties have been studied by NMR, UV–vis and fluorescence

An easy assembled fluorescent sensor for dicarboxylates and acidic amino acids

• Xiao-bo Zhou,
• Yuk-Wang Yip,
• Wing-Hong Chan and
• Albert W. M. Lee

Beilstein J. Org. Chem. 2011, 7, 75–81, doi:10.3762/bjoc.7.11

• dicarboxylates. Conclusion This study examined the binding properties of two ditopic receptors 1 and 2 for various dicarboxylates using fluorescence and 1H NMR spectroscopic methods. As revealed by the respective association constants, among all studied dicarboxylates, sensor 1 showed the highest affinity to

Anthracene appended pyridinium amide–urea conjugate in selective fluorometric sensing of L-N-acetylvaline salt

• Kumaresh Ghosh,
• Tanmay Sarkar and
• Asoke P. Chattopadhyay

Beilstein J. Org. Chem. 2010, 6, 1211–1218, doi:10.3762/bjoc.6.139

• emission decay of 2 was monitored at 418 nm in the presence of L-N-acetylvaline salt upon excitation at 370 nm. This observation is thus noteworthy since it distinguishes the L-N-acetylvaline salt in the present study form the others with receptor 1. Concurrently, the ground state binding properties of 1

En route to photoaffinity labeling of the bacterial lectin FimH

• Thisbe K. Lindhorst,
• Michaela Märten,
• Andreas Fuchs and
• Stefan D. Knight

Beilstein J. Org. Chem. 2010, 6, 810–822, doi:10.3762/bjoc.6.91

• , FimHtr, which resembles the adhesin domain of the complete FimH, was used [24]. FimHtr comprises of amino acids 1-160 of FimH and is terminated by a histidine tag His6. FimHtr has the same carbohydrate binding properties as FimH. Mass spectrometric analysis of FimHtr revealed m/z = 17839 (calcd. m/z

Anthracene coupled adenine for the selective sensing of copper ions

• Kumaresh Ghosh and
• Tanushree Sen

Beilstein J. Org. Chem. 2010, 6, No. 44, doi:10.3762/bjoc.6.44

• of an anthracenyl group (a flat hydrophobic surface) at the different positions in adenine leads to the preferential binding of Cu2+ ion over Ag+ and other transition metal ions studied. In this connection, adenine-based receptors 1 and 2 (Scheme 1) have been synthesized and their metal ion binding

• properties have been studied by UV–vis and fluorescence methods. Both 1 and 2 are found to be selective for Cu2+ in CH3CN containing 0.02% DMSO. Importantly, 1 is found to be more efficient binder than 2 as reflected in the study. Results and Discussion The syntheses of 1 and 2 are outlined in Scheme 2

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

• showed a considerable binding affinity and enantiomeric discrimination of aromatic amine salts [162]. The binding properties were evaluated by 1H NMR titration in acetonitrile. For the (R,R)- and (S,S)-configurated host with a phenyl residue, the highest differences in the Kass values were observed: (R

Templated versus non-templated synthesis of benzo-21-crown-7 and the influence of substituents on its complexing properties

• Wei Jiang and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2010, 6, No. 14, doi:10.3762/bjoc.6.14

• . Modification of crown ethers and their secondary ammonium guests allows variation of their binding properties and enables them to be incorporated into more complex assemblies [28]. In this respect, benzocrown ethers are more preferable than their aliphatic analogs due to the easy-to-achieve substitution on the

Synthesis of indolo[3,2-b]carbazole-based new colorimetric receptor for anions: A unique color change for fluoride ions

• Ajit Kumar Mahapatra,
• Giridhari Hazra and
• Prithidipa Sahoo

Beilstein J. Org. Chem. 2010, 6, No. 12, doi:10.3762/bjoc.6.12

• same plane as the carbazole unit. Interaction studies UV–vis study The anion-binding properties of receptor 1 were investigated by UV–vis, fluorescence and 1H NMR spectroscopic methods. The sensing ability of chemosensor 1 with a series of tetrabutylammonium salts ([Bu4N]+X−, X = F−, Cl−, Br−, I−, AcO

Recognition properties of receptors consisting of imidazole and indole recognition units towards carbohydrates

• Monika Mazik and
• André Hartmann

Beilstein J. Org. Chem. 2010, 6, No. 9, doi:10.3762/bjoc.6.9

• units as the entities used in nature, and 2-aminopyridine group as a heterocyclic analogue of the asparagine/glutamine primary amide side chain, were prepared and their binding properties towards carbohydrates were studied. The design of these receptors was inspired by the binding motifs observed in the

• glycosides. It has been shown that both hydrogen bonding and interactions of the carbohydrate CH units with the aromatic rings of the receptors contribute to the stabilization of the receptor–carbohydrate complexes. The molecular modeling calculations, synthesis and binding properties of 4 and 5 towards

• with mono- and disaccharide substrates. Herein, we describe the synthesis, molecular modeling calculations and the binding properties of the compounds 4 and 5. To compare the binding properties of the new compounds with those of the previously published receptors, octyl β-D-glucopyranoside (6a), methyl