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Search for "molecular tweezers" 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
- Pablo Msellem Maksym Dekthiarenko Nihal Hadj Seyd Guillaume Vives Sorbonne Université, UMR CNRS 8232, Institut Parisien de Chimie Moléculaire, 4 place Jussieu, 75005, Paris, France 10.3762/bjoc.20.45 Abstract Switchable molecular tweezers are a unique class of molecular switches that, like their
- macroscopic analogs, exhibit mechanical motion between an open and closed conformation in response to stimuli. Such systems constitute an essential component of artificial molecular machines. This review will present selected examples of switchable molecular tweezers and their potential applications. The
- chemistry; Introduction The terminology “molecular tweezers” was first introduced by Chen and Whitlock in 1978 through a seminal paper [1], wherein they presented a water-soluble molecular receptor composed of two caffeine recognition units linked by a semi-rigid diyne spacer. This ingenious design enabled
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.
Automated high-content imaging for cellular uptake, from the Schmuck cation to the latest cyclic oligochalcogenides
- Rémi Martinent,
- Javier López-Andarias,
- Dimitri Moreau,
- Yangyang Cheng,
- Naomi Sakai and
- Stefan Matile
Beilstein J. Org. Chem. 2020, 16, 2007–2016, doi:10.3762/bjoc.16.167
- library of 259 molecular tweezers through an ethidium bromide (EB) displacement assay, show a negligible DNA transfection efficiency (Figure 3). However, the derivative 15, with two lipophilic hydrocarbon chains, results in a remarkable DNA delivery and transfection [35]. These two hydrocarbon chains
Graphical Abstract
Figure 1: Schematic representation of binding models between organic cations (simple ammonium, guanidinium, S...
Figure 2: From Schmuck cations to cell-penetrating dipeptides, with schematic representation of the binding m...
Figure 3: Peptide tweezers and cyclic peptides with Schmuck cations for gene transfection.
Figure 4: Evolution from CPPs to CPDs and COCs.
Figure 5: Structure of a) the trifunctional transporter 23 and c) the HaloTag reporter 26. b) Schematic mecha...
Figure 6: CAPA assay for the complex 25, composed of three transporters 23 bound to one streptavidin 24 (with...
Figure 7: Examples from the automated HC imaging of stable HGM cells with HaloTag–GFP on mitochondria, labele...
Figure 8: Evaluation of the automated HC imaging of stable HGM cells with HaloTag–GFP on mitochondria, labele...
Figure 9: a) Automated HC imaging of the cellular uptake of 25, covering the concentration dependence for the...
Figure 10: Examples of automated HC imaging of transiently transfected HeLa cells with HaloTag–GFP on Golgi, l...
Figure 11: Evaluation of the automated HC imaging of the transiently transfected HeLa cells with HaloTag–GFP o...
Complexation of molecular clips containing fragments of diphenylglycoluril and benzocrown ethers with paraquat and its derivatives
- Leonid S. Kikot',
- Catherine Yu. Kulygina,
- Alexander Yu. Lyapunov,
- Svetlana V. Shishkina,
- Roman I. Zubatyuk,
- Tatiana Yu. Bogaschenko and
- Tatiana I. Kirichenko
Beilstein J. Org. Chem. 2017, 13, 2056–2067, doi:10.3762/bjoc.13.203
- on crown ethers differing in the structure of the intramolecular cavity and in the type of complexation, is still relevant. Among the large variety of synthetic receptors, so-called molecular tweezers and clips are of interest [16][17]. These are a particular case of U-shaped hosts, highly
- centers, similar to the operating principle of mechanical clips. The most promising for the interaction with paraquat derivatives are molecular tweezers and clips containing fragments of crown ethers, although such examples are not numerous. Nolte et al. showed that the introduction of a glycoluril moiety
- complexation with a variety of guests has been studied [19][20][21][22][23][24][25]. Recently, they have obtained new molecular tweezers containing a tetraphenylene group as rigid fragment and two dibenzo-24-crown-8 fragments as side arms, and their complexation with paraquat derivatives have been investigated
Graphical Abstract
Figure 1: Chemical structures of hosts 1–6 and guests 7–10.
Figure 2: HF/6-311+G** calculated 3D molecular electrostatic potential of the guests 7–10. The color code spa...
Figure 3: Partial 1H NMR spectra (300 MHz, CD3CN/CDCl3 4:3, v/v) of (a) free host 3, (b) 3 and 1.0 equiv of 7...
Figure 4: The changes observed in the UV–vis spectra during the titration of clip 2 with paraquat (7) in acet...
Figure 5: Stability constant dependence for the complexes (lgK) of molecular clips 1–5 with guests 7–10 on th...
Figure 6: Molecular structures of complexes of clips 3, 2 and 5 with paraquat (7). Anions and solvate molecul...
Figure 7: Crystal packing of molecules in complexes of clips 2, 3 and 5 with paraquat (7). Anions and solvate...
Figure 8: Molecular structures of complexes 2@8 and 3@8. The hydrogen bonds are shown by blue lines. Anions a...
Figure 9: Molecular structures of complexes 2@9 and 3@9. The hydrogen bonds are represented by blue lines. An...
Figure 10: Molecular structures of complexes 2@10 and 3@10. Anions and solvate molecules are omitted for clari...
A journey in bioinspired supramolecular chemistry: from molecular tweezers to small molecules that target myotonic dystrophy
- Steven C. Zimmerman
Beilstein J. Org. Chem. 2016, 12, 125–138, doi:10.3762/bjoc.12.14
- early career efforts in molecular recognition, especially molecular tweezers. Although designed to complex DNA, these hosts proved more applicable to the field of host–guest chemistry. This early experience and interest in intercalation ultimately led to the current efforts to develop small molecule
- tweezers and a paradigm shift in host–guest chemistry Developing molecular tweezers was one of the main projects I started in my independent academic career at Illinois. The idea originated at Columbia when I began to teach myself the biochemistry and biology lacking in any of my formal coursework. For
- Saionz covalently linked the molecular tweezers to silica gel (see 5, Figure 3), making chemically bonded stationary phases which were packed into HPLC columns that selectively retained and separated nitrated aromatics [13]. The HPLC columns proved to be very useful for quickly measuring ΔΗ° of
Graphical Abstract
Figure 1: Photographs of Howard E. Zimmerman (July 5, 1926–February 12, 2012) (left) and Jane Zimmerman (née ...
Figure 2: (a) Schematic double helix fully saturated with intercalator (in purple) according to the neighbor ...
Figure 3: Bismethidium molecular tweezer 3 proposed as a graduate student at Columbia University, which was q...
Figure 4: Adenine 8 recognition by carboxylic acid containing tweezer 9 and a component analysis showing “com...
Figure 5: The first determination of the cost of freezing single bond rotations in a host–guest complex.
Figure 6: Glycouril-based molecular clip 16 and 17 developed by Nolte, an example of Harmata’s chiral Kagan-e...
Figure 7: Macrocyclic diacridines and dinaphthalene and the intercalation complexes they may form with one ch...
Figure 8: (a) Hairpin structure of CUGexp seen in (CUG)12. (b) U–U or T–T mismatches with no inter-strand hyd...
Figure 9: (a) CTG trinucleotide repeat expansion in DMPK gene produces expanded transcripts, one which CUGexp...
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
- ]. Thus, oligomers 13–15 may be considered as structural prototypes for creating new modifiable backbones. For example, porphyrin-appended U-shaped molecular tweezers 16 and 17 have been produced (Scheme 8). Compound 16 complexed C60 or C70 or their derivatives in chloroform or toluene through porphyrin
Graphical Abstract
Scheme 1: Proposed structures of complexes between 1a and 1b with 2.
Scheme 2: The formation of catenanes 6a–c.
Scheme 3: The structures of cantenanes 7a–c.
Scheme 4: The structures of dimer 8·8 and compounds 9 and 10.
Figure 1: X-ray structure of 10 showing a quadruple hydrogen-bonded dimeric motif [17].
Scheme 5: The structures of compounds 11a–g.
Figure 2: Zipper-featured folding motif of δ-peptides 11a–g driven by the cooperative donor–acceptor interact...
Scheme 6: The structures of compounds 12a–g and the formation of the helical conformation by the longer oligo...
Scheme 7: The structures of compounds 13a,b, 14, and 15a–d.
Scheme 8:
The structures of complex C60 ![[Graphic 1]](/bjoc/content/inline/1860-5397-11-222-i19.png?max-width=637&scale=1.18182)
16 and dynamic [2]catenane formed by compounds 17–19.
Scheme 9: The structure of homodimers 20a·20a and 20b·20b.
Scheme 10: The structures of foldamers 21 and 22a–c.
Scheme 11: Complexation-promoted hydrolysis of foldamer 23.
Scheme 12: The structure of foldamer 24.
Scheme 13: The structures of foldamers 24a–c.
Scheme 14: Proposed structures of heterodimers 25·28, 26·28, and 27·28.
Scheme 15: Proposed structure of complex formed by 29 and 30.
Scheme 16: The structures of polymers P31a,b and P32a–d.
Scheme 17: The structure of compound 33.
Scheme 18: The structure of compound 34.
Glycoluril–tetrathiafulvalene molecular clips: on the influence of electronic and spatial properties for binding neutral accepting guests
- Yoann Cotelle,
- Marie Hardouin-Lerouge,
- Stéphanie Legoupy,
- Olivier Alévêque,
- Eric Levillain and
- Piétrick Hudhomme
Beilstein J. Org. Chem. 2015, 11, 1023–1036, doi:10.3762/bjoc.11.115
- second oxidation step (Eapp0ox2) leading to fully oxidized TTF units is in accordance with independent TTF2+ states subject to repulsive electrostatic interactions. Such splitting phenomenon of the first oxidation wave has been previously reported by Azov et al. for TTF-containing molecular tweezers
Graphical Abstract
Figure 1: Structures of molecular clips 1–4.
Scheme 1: Different routes developed for the synthesis of molecular clips 1–4.
Scheme 2: Reaction between diphenylglycoluril with 4,5-bis(bromomethyl)-2-thioxo-1,3-dithiole.
Figure 2: Intramolecular distances between TTF moieties from X-ray analysis for clips 2 and 3 and theoretical...
Figure 3: Cyclic voltammograms of molecular clips 1, 2, 3, 4 and F4-TCNQ at 10−3 M in 0.1 M TBAPF6/CH2Cl2/CH3...
Figure 4: Cyclic voltammograms of molecular clip 2 at different concentrations (left: 10−5 M; middle: 10−4 M;...
Scheme 3: Graphical representation of the stepwise oxidation of molecular clips 1, 2 and 3.
Scheme 4: Electrochemical mechanism used to simulate the CVs of molecular clips 1, 2 and 3.
Figure 5: Chemical oxidation of molecular clip 1 (10−4 M, CH2Cl2) using aliquots of NOSbF6 oxidizing reagent ...
Figure 6: Spectroelectrochemical experiment of molecular clip 1 during the first oxidation step at different ...
Figure 7: Molecular structure of molecular clip 15 and representation of its stepwise oxidation processes pro...
Figure 8: Molecular packing diagram of clips 2 (left) and 3 (right) obtained from X-ray analysis. A molecule ...
Figure 9: Left: Job plot analysis for DNB vs molecular clip 3 ([3 + DNB] = 10−3 M in o-C6H4Cl2 at 800 nm) at ...
Figure 10: UV–visible absorption spectra of F4-TCNQ (CH2Cl2, 10−5 M) upon titration with molecular clip 3 (CH2...
Figure 11: Redox interaction (left) and complexation (right) of F4-TCNQ with molecular clips 3 and 4.
Charge-transfer interaction mediated organogels from 18β-glycyrrhetinic acid appended pyrene
- Jun Hu,
- Jindan Wu,
- Qian Wang and
- Yong Ju
Beilstein J. Org. Chem. 2013, 9, 2877–2885, doi:10.3762/bjoc.9.324
- ability of 2,3-dihydroxyiminooleanolic acid, adenineoleanolic acid conjugates as well as the fan-shaped C3 and molecular tweezers based on glycyrrhetinic acid [42][43][44]. In this paper, 18β-glycyrrhetinic acid–pyrene (GA-Pyrene, 3) as the electron donor, and 2,4,7-trinitrofluorenone (TNF, 4) as the
Graphical Abstract
Scheme 1: Reagents and reaction conditions: (a) 4-dimethylaminopyridine (DMAP), 1-ethyl-3-(3-dimethylaminopro...
Figure 1: (a) GA-pyrene (3) and TNF (4, 1:1, molar ratio, [3] = 12 mM) in DMSO/water (3:1, v/v). The red inso...
Figure 2: Tgel of GA-pyrene (3) and TNF (4, 1:1, molar ratio) with the increasing concentration in different ...
Figure 3: Tgel of all the CT gels of GA-pyrene (3, 0.6 g/100 mL) with TNF (4) in varying ratios.
Figure 4: Scanning electron micrographs of CT xerogels (3 and 4, 1:1, molar ratio, [3] = 9 mM) in DMSO/water ...
Figure 5: Optical micrographs (20 × 20) of CT xerogels (3 and 4, 1:1, molar ratio, [3] = 9 mM) in (a) DMSO/wa...
Figure 6: CD spectra of sol in CH2Cl2, and CT gel obtained from DMF/water (3:1, v/v), DMSO/water (3:1, v/v), ...
Figure 7: (a) UV–vis, (b) transmittance at 700 nm, (c) fluorescence intensity at 498 nm (excitation: 365 nm) ...
Figure 8: Variable temperature 1H NMR (400 MHz) of CT gel (3 and 4, 1:1, molar ratio) in DMSO/D2O (3:1, v/v)....
Preparation, structures and preliminary host–guest studies of fluorinated syn-bis-quinoxaline molecular tweezers
- Markus Etzkorn,
- Jacob C. Timmerman,
- Matthew D. Brooker,
- Xin Yu and
- Michael Gerken
Beilstein J. Org. Chem. 2010, 6, No. 39, doi:10.3762/bjoc.6.39
- 10.3762/bjoc.6.39 Abstract A series of polycyclic frameworks with fluorinated syn-facial quinoxaline sidewalls has been prepared as potential molecular tweezers for electron-rich guest compounds. Our synthetic route to the cyclooctadiene-derived scaffolds 16a–d takes advantage of the facile isolation of a
- , host–guest NMR studies of compound 16c in solution show chemical exchange between the unbound and bound electron-rich guest, N,N,N′,N′-tetramethyl-p-phenylenediamine. Keywords: crystal structure; fluorine; molecular tweezers; quinoxalines; self-association; Introduction A broad variety of
- structurally diverse molecular tweezers, i.e., scaffolds in which a tether unit connects two syn-oriented aromatic pincers, are well-established as devices for the molecular recognition of mostly electron-deficient guest compounds [1][2][3][4][5][6][7][8][9][10]. Conversely, molecular tweezers with a binding
Graphical Abstract
Scheme 1: Fluorinated molecular tweezers.
Scheme 2: Synthesis of non-fluorinated and fluorinated syn-bis-quinoxalines.
Figure 1: (a) Thermal ellipsoid image of the tweezer molecular 16c in the structure 16c · CH3CO2C2H5; thermal...
Figure 2: Electrostatic potential surfaces of 16a–c (Spartan 06 [41]: B3LYP/6-31G*//B3LYP/6-31G*; legend in kcal/...
Figure 3: 1H NMR spectra (CD2Cl2, 500 MHz) of 16c (host [black]) upon titration with N,N,N′,N′-tetramethyl-p-...
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
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...
