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Search for "ion recognition" in Full Text gives 9 result(s) in Beilstein Journal of Organic Chemistry.
Switchable molecular tweezers: design and applications
- Pablo Msellem,
- Maksym Dekthiarenko,
- Nihal Hadj Seyd and
- Guillaume Vives
Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45
- allosteric binding to alkali K+ cations associated with a shift in the emission maxima. This system offers innovative exploitation of switchable molecular tweezers for allosteric ion recognition with a double selection (metallic ion and counter anion) of the closing stimulus. Closed-by-default tweezers can
Graphical Abstract
Figure 1: Principle of switchable molecular tweezers.
Figure 2: Principle of pH-switchable molecular tweezers 1 [19].
Figure 3: a) pH-Switchable tweezers 2 substituted with alkyl chains as switchable lipids. b) Schematic depict...
Figure 4: Modification of spectral properties of 3 by controlled induction of Pt–Pt interactions.
Figure 5: Conformational switching of di(hydroxyphenyl)pyrimidine-based tweezer 4 upon alkylation or fluoride...
Figure 6: Hydrazone-based pH-responsive tweezers 5 for mesogenic modulation.
Figure 7: pH-Switchable molecular tweezers 6 bearing acridinium moieties.
Figure 8: a) Terpyridine and pyridine-hydrazone-pyridine analogs molecular tweezers and b) extended pyridine ...
Figure 9: Terpyridine-based molecular tweezers with M–salphen arms and their field of application. Figure 9 was adapt...
Figure 10: a) Terpyridine-based molecular tweezers for diphosphate recognition [48]; b) bishelicene chiroptical te...
Figure 11: Terpyridine-based molecular tweezers with allosteric cooperative binding.
Figure 12: Terpyridine-based molecular tweezers presenting closed by default conformation.
Figure 13: Pyridine-pyrimidine-pyridine-based molecular tweezers.
Figure 14: Coordination-responsive molecular tweezers based on nitrogen-containing ligands.
Figure 15: Molecular tweezers exploiting the remote bipyridine or pyridine binding to trigger the conformation...
Figure 16: Bipyridine-based molecular tweezers exploiting the direct s-trans to s-cis-switching for a) anion b...
Figure 17: a) Podand-based molecular tweezers [66,67]. b) Application of tweezers 32 for the catalytic allosteric reg...
Figure 18: Anion-triggered molecular tweezers based on calix[4]pyrrole.
Figure 19: Anion-triggered molecular tweezers.
Figure 20: a) Principle of the weak link approach (WLA) developed by Mirkin and its application to b) symmetri...
Figure 21: Molecular tweezers as allosteric catalyst in asymmetric epoxide opening [80].
Figure 22: Allosteric regulation of catalytic activity in ring-opening polymerization with double tweezers 41.
Figure 23: a) Conformational switching of 42 by intramolecular –S–S– bridge formation. b) Shift of conformatio...
Figure 24: a) Redox-active glycoluril-TTF tweezers 44. b) Mechanism of stepwise oxidation of said tweezers wit...
Figure 25: Mechanism of formation of the mixed-valence dimers of tweezers 45.
Figure 26: Mechanism of carbohydrate liberation upon redox-mediated conformation switching of 46.
Figure 27: a) The encapsulation properties of 47 as well as the DCTNF release process from its host–guest comp...
Figure 28: Redox-active bipyridinium-based tweezers. a) With a ferrocenyl hinge 49, b) with a propyl hinge 50 ...
Figure 29: Redox-active calix[4]arene porphyrin molecular tweezers.
Figure 30: a) Mechanism of the three orthogonal stimuli. b) Cubic scheme showing the eight different states of ...
Figure 31: Redox-controlled molecular gripper based on a diquinone resorcin[4]arene.
Figure 32: a) Shinkai's butterfly tweezers and their different host–guest properties depending on the isomer. ...
Figure 33: Cyclam-tethered tweezers and their different host–guest complexes depending on their configuration.
Figure 34: Azobenzene-based catalytic tweezers.
Figure 35: Photoswitchable PIEZO channel mimic.
Figure 36: Stilbene-based porphyrin tweezers for fullerene recognition.
Figure 37: Stiff-stilbene-based tweezers with urea or thiourea functional units for a) anion binding, b) anion...
Figure 38: Feringa’s photoswitchable organocatalyst (a) and different catalyzed reactions with that system (b)....
Figure 39: a) Irie and Takeshita’s thioindigo-based molecular tweezers. b) Family of hemithioindigo-based mole...
Figure 40: Dithienylethylene crown ether-bearing molecular tweezers reported by Irie and co-workers.
A fluorescent probe for detection of Hg2+ ions constructed by tetramethyl cucurbit[6]uril and 1,2-bis(4-pyridyl)ethene
- Xiaoqian Chen,
- Naqin Yang,
- Yue Ma,
- Xinan Yang and
- Peihua Ma
Beilstein J. Org. Chem. 2023, 19, 864–872, doi:10.3762/bjoc.19.63
- ; fluorescent probe; Hg2+ ion recognition; host–guest chemistry; tetramethyl cucurbit[6]uril; Introduction Mercury, as one of the most toxic heavy metal pollutants, not only seriously pollutes the ecological environment but also causes great harm to human health. Mercury and inorganic mercury ions (Hg2+) in
Graphical Abstract
Figure 1: Supramolecular assembly of TMeQ[6] and 1,2-bis(4-pyridyl)ethene (G).
Figure 2: (a) UV–vis titration of G (3.0 × 10−5 mol·L−1, pH 6.5) in aqueous solution with the increase of TMe...
Figure 3: (a) Fluorescence spectra (U = 550 V, pH 6.5) of G (3.0 × 10−5 mol·L−1) in aqueous solution with inc...
Figure 4: (a) Crystal structure of complex 1; (b) and (c) the binding mode of G with TMeQ[6]; (d) the supramo...
Figure 5: (a) Fluorescence response of G (3.0 × 10−5 mol·L−1) to metal cations in aqueous solution; (b) fluor...
Figure 6: Influence of coexisting ions on Hg2+ detection by G@TMeQ[6].
Figure 7: (a) Fluorescence titration curve (U = 500 V, pH 6.5) of probe G@TMeQ[6] (3.0 × 10−5 mol·L−1) to Hg2+...
Figure 8: (A) Titration 1H NMR spectra (400 MHz) obtained for TMeQ[6] with (a) 0.00, (b) 0.50, (c) 1.00 and (...
Tautomerism as primary signaling mechanism in metal sensing: the case of amide group
- Vera Deneva,
- Georgi Dobrikov,
- Aurelien Crochet,
- Daniela Nedeltcheva,
- Katharina M. Fromm and
- Liudmil Antonov
Beilstein J. Org. Chem. 2019, 15, 1898–1906, doi:10.3762/bjoc.15.185
- development of natural ligand-supported metal investigations. The ion recognition is based on the existence of two molecular states (ligand and complex) with different optical properties and a structure that allows fast transfer from the ligand to the complex upon addition of the desired metal ion [7]. The
Graphical Abstract
Scheme 1: Conceptual idea for tautomeric metal sensing.
Scheme 2: 4-(Phenyldiazenyl)naphthalen-1-ol (1) and tautomeric ligands based on it.
Figure 1: The most stable tautomeric form of 6 in neutral state (left) and upon complexation with Mg(ClO4)2 (...
Figure 2: Absorption spectra of compounds 1 (a) and 6 (b) in acetonitrile (—), chloroform (− · −), dichlorome...
Figure 3: Left: Theoretically predicted structure of 6K (blue), overlaid with the X-ray structure (red). Righ...
Figure 4: Left: Absorption spectra of 6 with stepwise addition of Mg(ClO4)2 in acetonitrile (1 – neutral liga...
Figure 5: Normalized spectra of the free ligand 6 (c = 5 × 10−5 M) and its complexes obtained with Ba(ClO4)2,...
Scheme 3: Synthetic route of 6.
N-doped carbon dots covalently functionalized with pillar[5]arenes for Fe3+ sensing
- Jia Gao,
- Ming-Xue Wu,
- Dihua Dai,
- Zhi Cai,
- Yue Wang,
- Wenhui Fang,
- Yan Wang and
- Ying-Wei Yang
Beilstein J. Org. Chem. 2019, 15, 1262–1267, doi:10.3762/bjoc.15.123
- units, the newly constructed fluorescent CCDs could recognize Fe3+ with high selectivity. Therefore, such CCDs can potentially serve as a promising chemical sensor for Fe3+ ions. Keywords: chemical sensor; CN-dots; fluorescence; ion recognition; supramolecular chemistry; Findings Carbon dots (C-dots
Graphical Abstract
Scheme 1: Schematic illustration of the synthesis of CCDs and its use for Fe3+ sensing.
Figure 1: TEM images of a) CCDs and b) CN-dots. c) UV–vis spectra of CP5, CN-dots, and CCDs. d) FTIR spectra ...
Figure 2: a) Photographs of CN-dots and CCDs in aqueous media in natural light, and under excitation with a U...
Figure 3: Fluorescence quenching degrees of a) CCDs and b) CN-dots in the presence of different metal ions. T...
Amidofluorene-appended lower rim 1,3-diconjugate of calix[4]arene: synthesis, characterization and highly selective sensor for Cu2+
- Rahman Hosseinzadeh,
- Mohammad Nemati,
- Reza Zadmard and
- Maryam Mohadjerani
Beilstein J. Org. Chem. 2016, 12, 1749–1757, doi:10.3762/bjoc.12.163
- supramolecular structures, especially calixarene derivatives, has been an appealing field for research [14]. Calixarene has been considered as an effective molecular scaffold in the improvement of fluorescent and chromogenic sensors, especially for metal-ion recognition [14][15]. Calix[4]arene derivatives having
Graphical Abstract
Scheme 1: Fluorene appended 1,3-diconjugate of calix[4]arene.
Scheme 2: Synthesis route of fluorene-appended amido-linked 1,3-diconjugate of calix[4]arene L.
Figure 1: Absorption spectra of L (1.0 × 10−5 M) and its complexes with different metals (10 equiv) in MeCN.
Figure 2: Color changes of receptor L upon addition of 10 equiv of various metal ions as their perchlorate sa...
Figure 3: Influence of the addition of increasing amounts (0–100 equiv) of Cu2+ on the absorption spectra of L...
Figure 4: Fluorescence spectra of L (1.0 × 10−5 M) in MeCN upon addition of different metal ions (10 equiv) w...
Figure 5: (a) Fluorescence spectra (1.0 × 10−5 M) of L recorded upon the addition of copper ion (0–5 equiv) i...
Figure 6: Fluorescence intensity of L (1.0 × 10−5 M) upon the addition of 10 equiv Cu2+ in the presence of 10...
Figure 7: 1 H NMR (400 MHz, CD3CN) spectra of L upon addition of (a) 0.0 equiv, (b) 0.2 equiv, (c) 0.4 equiv,...
Scheme 3: A proposed binding mode between L and Cu2+.
From steroids to aqueous supramolecular chemistry: an autobiographical career review
- Bruce C. Gibb
Beilstein J. Org. Chem. 2016, 12, 684–701, doi:10.3762/bjoc.12.69
Graphical Abstract
Scheme 1: The formation of a 1:1 complex and a 2:1 supramolecular nano-capsule complex from bowl-shaped “cavi...
Scheme 2: Abbreviated synthesis of 7-amino-2-phenyl-6-azaindolizine.
Figure 1: My two favorite compounds for my Ph.D. dissertation, “The Synthesis and Structural Examination of 3...
Scheme 3: An inspiring chlorination from the group of Ronald Breslow.
Scheme 4: The carceplex reaction.
Figure 2: Schematic of a cavitein.
Figure 3: General structure of zinc-TPA complexes.
Scheme 5: Stereoselective bridging of a resorcinarene with benzal halides.
Scheme 6: An eight-fold Ullman ether “weaving” reaction.
Scheme 7: Directed ortho-metallation of the deep-cavity cavitands, showing the mono-endo substituted to tetra-...
Scheme 8: Macrocycle synthesis via resorcinarene covalent templates.
Figure 4: Tris-pyridyl hosts.
Figure 5: (Center) Chemical structure of the octa-acid host. (Left and right) Respective space-filling repres...
Figure 6: Cartoons of the 2:1 host–guest complexes of estradiol (left) and cholesterol (right).
Figure 7: Representative guests for the capsular complexes formed by octa-acid (stoichiometry shown in parent...
Figure 8: A dendrimer-coated cavitand.
Figure 9: Selective oxidation of olefins by singlet oxygen.
Figure 10: a) Preferred packing motifs of methyl, pentyl and octyl guests. b) Product distribution observed fo...
Figure 11: Schematic of the competition of two esters for the capsule formed by octa-acid. The ester that bind...
Figure 12: Schematic of the inter-phase separation of propane and butane; the latter binds more strongly to th...
Figure 13: Structure of tetra-endo-methyl octa-acid (TEMOA).
Figure 14: Assembly properties of TEMOA.
Figure 15: How salts influence the association constant (Ka) for the binding of ClO4– to octa-acid (Figure 4). The ind...
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
- . Keywords: amino acids; dicarboxylate ion recognition; enantioselectivity; mesitylene scaffold; Introduction The recognition and sensing of anionic substrates by positively charged or electrically neutral synthetic receptive molecular systems has emerged as a key research area because of the fundamental
Graphical Abstract
Scheme 1: Synthesis of sensor 1 and 2.
Figure 1: The changes in the fluorescence emission spectra of sensor 1 (5.0 × 10−6 M) upon addition of isopht...
Figure 2: Proposed three sites binding model for sensor 2 and glutamate complex.
Figure 3: Partial 1H NMR spectra for (a) sensor 2 (free, 3 mM), (b) sensor 2 + 0.5 equiv D-glutamate, (c) sen...
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
- Kumaresh Ghosh Tanushree Sen Department of Chemistry, University of Kalyani, Kalyani-741235, India 10.3762/bjoc.6.44 Abstract Anthracene-based adenines 1 and 2 have been designed and synthesized, and their metal ion recognition properties have been established fluorometrically. Both molecules
- selective; fluorescence; metal ion recognition; PET sensory systems; Introduction Fluorescent chemosensors for the detection of biologically relevant metal ions have been widely exploited in the field of supramolecular chemistry [1][2][3][4]. Among the various transition metal ions, the copper ion draws
- the WC sites are marginally increased (Figure 2). Fluorescence and UV–vis spectroscopic techniques were then employed to ascertain the metal ion recognition properties of both 1 and 2 in solution. Receptor 1 (c = 5.09 × 10−5 M) upon excitation at 348 nm in CH3CN containing 0.02% DMSO showed structured
Graphical Abstract
Scheme 1: Adenine-based receptors 1 and 2.
Scheme 2: Syntheses of receptors 1 and 2.
Figure 1: Design principle for 1 and 2.
Figure 2: AM1 optimized geometries of 1 (E = −162.48 au) of 2 (E = −139.59 au).
Figure 3: a) Fluorescence ratio (I-I0/I0) of receptor 1 (c = 5.09 × 10−5 M) at 413 nm upon addition of 20 equ...
Figure 4: Emission spectra of receptor 1 (c = 5.09 × 10−5 M) during titration with Cu2+ ion (c = 1.4 × 10−3 M...
Figure 5: a) Emission spectra of receptor 2 (c = 1.48 × 10−5 M) during titration with Cu2+ ion (c = 4.4 × 10−4...
Figure 6: Stern–Volmer plot of receptor 2 (c = 1.48 × 10−5 M) at 413 nm upon addition of 20 equiv of a partic...
Figure 7: Change in emission of 1 (c = 8.66 × 10−5 M) (a) and 2 (c = 1.29 × 10−4 M) (b) upon addition of 10 e...
Figure 8: a) Binding constant curve for 1 with Cu2+ ion; b) binding constant curve for 2 with Cu2+ ion.
Figure 9: a) Absorption spectra of receptor 1 (c = 5.09 × 10−5 M) upon gradual addition of Cu2+ ion (c = 1.4 ...
Figure 10: a) Absorption spectra of receptor 2 (c = 1.48 × 10−5 M) upon gradual addition of Ag+ ion (c = 4.4 ×...
Figure 11: Absorption spectra of anthracene (c = 2.39 × 10−5 M) upon gradual addition of Cu2+ ion (c = 1.20 × ...
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
- , hydrophobic interactions or reversible covalent bond formation. In this review we discuss the different classes of synthetic receptors for organic ammonium ion recognition and illustrate the scope and limitations of each class with selected examples from the recent literature. The molecular recognition of
- understanding of alkylammonium recognition in the dopamine (2) class of neurotransmitters is key to the development of tools to study these systems. Therefore the investigation of ammonium ion recognition is of considerable fundamental and practical interest [7][120]. Selective ligand-protein receptor binding
- be covered. The recognition of guanidinium ions and metal cations [50] is not included. Ion pair recognition will be discussed briefly if it is relevant for ammonium ion recognition purposes. A comprehensive review on this topic has been published by Sessler et al. [51][52][53]. We also discuss the
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
