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Search for "cryptands" in Full Text gives 11 result(s) in Beilstein Journal of Organic Chemistry.
Tying a knot between crown ethers and porphyrins
- Maksym Matviyishyn and
- Bartosz Szyszko
Beilstein J. Org. Chem. 2023, 19, 1630–1650, doi:10.3762/bjoc.19.120
- synthesis of three-dimensional cryptands by Lehn [5], and spherands by Cram [6]. Later on, various classes of macrocyclic compounds were designed, demonstrating remarkable features in areas spreading from simple coordination chemistry [7], through host–guest chemistry, sensing [8], biomedicine [9], and
Graphical Abstract
Figure 1: Porphyrin and crown ether.
Figure 2: Timeline demonstrating the contributions into the crown ether–porphyrin chemistry.
Figure 3: Tetra-crowned porphyrin 1 and dimer 2 formed upon K+ binding.
Figure 4: meso-Crowned 25-oxasmaragdyrins 3a–c and their boron(III) complexes (3a–c)-BF2.
Scheme 1: CsF ion-pair binding of 4. The molecular structure of 4-CsF is shown on the right [101].
Figure 5: CsF ion pair binding by 5. The molecular structure of 5-CsF is shown on the right [102].
Scheme 2: Ion-pair binding by 6. The molecular structure of (6-CsCl)2 is shown on the right [103].
Scheme 3: Hydrated fluoride binding by 7 [104].
Figure 6: β-Crowned porphyrin 8.
Figure 7: Crown ether-capped porphyrins 9.
Figure 8: The capped porphyrin 10 and complex [10-PQ](PF6)2.
Figure 9: The double-capped porphyrin 11.
Figure 10: Selected examples of iminoporphyrinoids [58,122].
Scheme 4: The synthesis of 13.
Scheme 5: Tripyrrane-based crown ether-embedding porphyrinoid 15.
Figure 11: Macrocycles 16–19 and their coordination compounds.
Scheme 6: The flexibility of 16-Co [66].
Figure 12: Hexagonal wheel composed of six 16-Co(III) monomers [66].
Scheme 7: The synthesis of 16-V [67].
Figure 13: The molecular structure of dimers [16-Mn]2 [67].
Scheme 8: Synthesis of crownphyrins 28–33. Compounds 23a/b and 29a/b were obtained from 4,7,10-trioxa-1,13-tr...
Figure 14: The molecular structures of 22a, 34a·(HCl)2, and 29b [69].
Figure 15: Molecular structures of 22a-Pb and (29b)2-Zn [69].
Scheme 9: Reactivity of 29a/b.
Scheme 10: Synthesis of 36 and 37 [131].
Scheme 11: Synthesis of 40–45.
Figure 16: Potential applications of porphyrin-crown ether hybrids.
Design and synthesis of a bis-macrocyclic host and guests as building blocks for small molecular knots
- Elizabeth A. Margolis,
- Rebecca J. Keyes,
- Stephen D. Lockey IV and
- Edward E. Fenlon
Beilstein J. Org. Chem. 2020, 16, 2314–2321, doi:10.3762/bjoc.16.192
- on cryptands [2], and Cram on hemicarcerands [3] demonstrated that preorganized macrocycles have the ability to act as hosts for various guest cations and compounds. Their seminal work was recognized with the 1987 Nobel Prize in Chemistry. More recently, the 2016 Nobel Prize in Chemistry was won by
Graphical Abstract
Figure 1: Structures of electron-rich bis-macrocyclic host 1, and electron-poor guests bis(ammonium) 2, and b...
Figure 2: (a) Hunter’s 77 backbone-atom trefoil knot–metal complex [9]. (b) The world’s smallest knot: Leigh’s 7...
Figure 3: Schematic representation of the second-generation TLC approach to a 73 backbone atom trefoil knot.
Scheme 1: Two routes to azidobromide 6.
Scheme 2: Initial route to core diester 13. aLigand = tris(2-benzimidazolylmethyl)amine.
Scheme 3: Better yielding route to core diester 13. aLigand = tris(2-benzimidazolylmethyl)amine.
Scheme 4: Saponification of 13 and bis-macrocyclization to form host 1.
Scheme 5: Synthesis of 23 backbone-atom bis(ammonium) guest 2.
Scheme 6: Synthesis of 25 backbone-atom bis(pyridinium) guest 3.
Novel macrocycles – and old ones doing new tricks
- Wei Jiang and
- Christoph A. Schalley
Beilstein J. Org. Chem. 2019, 15, 1838–1839, doi:10.3762/bjoc.15.178
- 10.3762/bjoc.15.178 Keywords: macrocycles; supramolecular chemistry; Macrocycles [1] are the workhorses in supramolecular chemistry. Many basic supramolecular concepts have been developed through studying crown ethers, cryptands, podands and spherands in the 1970s and 1980s. For these contributions
Synthesis of (macro)heterocycles by consecutive/repetitive isocyanide-based multicomponent reactions
- Angélica de Fátima S. Barreto and
- Carlos Kleber Z. Andrade
Beilstein J. Org. Chem. 2019, 15, 906–930, doi:10.3762/bjoc.15.88
- of nonsymmetric cryptands by two sequential double Ugi-4CR-based macrocyclizations (Scheme 28). The approach also relies on MiBs strategy [45]. The main focus was on the use of the Ugi four-component reaction (Ugi-4CR) due to the tremendous capability of this process to generate molecular complexity
- macrocycles [40]. Synthesis of cholane-based hybrid macrolactams by MiBs [41]. Synthesis of macrocyclic oligoimine-based DCL using the Ugi-4CR-based quenching approach [42]. Dye-modified and photoswitchable macrocycles by MiBs [43]. Synthesis of nonsymmetric cryptands by two sequential double Ugi-4CR-based
Graphical Abstract
Scheme 1: Comparison between a normal sequential reaction and an MCR.
Scheme 2: Synthesis of tetrazoles and hydantoinimide derivatives by consecutive Ugi reactions [17].
Scheme 3: Synthesis of tetrazole-ketopiperazines by two consecutive Ugi reactions [19].
Scheme 4: Synthesis of acylhydrazino bis(1,5-disubstituted tetrazoles) through two hydrazine-Ugi-azide reacti...
Scheme 5: Synthesis of substituted α-aminomethyltetrazoles through two consecutive Ugi reactions (U-4CR and U...
Scheme 6: Synthesis of tetrazole peptidomimetics by direct use of amino acids in two consecutive Ugi reaction...
Scheme 7: One-pot 8CR based on 3 sequential IMCRs [25].
Scheme 8: Combination of IMCRs for the synthesis of substituted 2H-imidazolines [25].
Scheme 9: 6CR involving a tandem combination of Groebke–Blackburn–Bienaymé and Ugi reaction for the synthesis...
Scheme 10: 5CR involving a tandem combination of Groebke–Blackburn–Bienaymé and Passerini reaction for the syn...
Scheme 11: Synthesis of tubugis via three consecutive IMCRs [27].
Scheme 12: Synthesis of telaprevir through consecutive IMCRs [28].
Scheme 13: Another synthesis of telaprevir through consecutive IMCRs [29].
Scheme 14: a) Synthetic sequence for accessing diverse macrocycles containing the tetrazole nucleus by the uni...
Scheme 15: a) Synthetic sequence for the tetrazolic macrocyclic depsipeptides using a combination of two IMCRs...
Scheme 16: Synthesis of cyclic pentapeptoids by consecutive Ugi reactions [32].
Scheme 17: Synthesis of a cyclic pentapeptoid by consecutive Ugi reactions [32].
Scheme 18: MW-mediated synthesis of a cyclopeptoid by consecutive Ugi reactions [33].
Scheme 19: Synthesis of six cyclic pentadepsipeptoids via consecutive isocyanide-based IMCRs [34].
Scheme 20: Microwave-mediated synthesis of a cyclic heptapeptoid through four consecutive IMCRs [35].
Scheme 21: Macrocyclization of bifunctional building blocks containing diacid/diisonitrile and diamine/diisoni...
Scheme 22: Synthesis of steroid-biaryl ether hybrid macrocycles by MiBs [38].
Scheme 23: Synthesis of biaryl ether-containing macrocycles by MiBs [39].
Scheme 24: Synthesis of natural product-inspired biaryl ether-cyclopeptoid macrocycles [40].
Scheme 25: Synthesis of cholane-based hybrid macrolactams by MiBs [41].
Scheme 26: Synthesis of macrocyclic oligoimine-based DCL using the Ugi-4CR-based quenching approach [42].
Scheme 27: Dye-modified and photoswitchable macrocycles by MiBs [43].
Scheme 28: Synthesis of nonsymmetric cryptands by two sequential double Ugi-4CR-based macrocyclizations [44].
Scheme 29: Synthesis of steroid–aryl hybrid cages by sequential 2- and 3-fold Ugi-4CR-based macrocyclizations [46]....
Scheme 30: Ugi-MiBs approach towards natural product-like macrocycles [47].
Scheme 31: a) Bidirectional macrocyclization of peptides by double Ugi reaction. b) Ugi-4CR for the generation...
Scheme 32: MiBs based on the Passerini-3CR for the synthesis of macrolactones [49].
Scheme 33: Template-driven approach for the synthesis of macrotricycles 170 [50].
Selectivity in multiple multicomponent reactions: types and synthetic applications
- Ouldouz Ghashghaei,
- Francesca Seghetti and
- Rodolfo Lavilla
Beilstein J. Org. Chem. 2019, 15, 521–534, doi:10.3762/bjoc.15.46
- [21], supramolecular structures (cryptands, cages, cryptophanes, podands, etc.) [22][23][24], cyclic/macrocyclic peptides [25] and other complex structures in a straightforward manner (Scheme 5). The diversity in these systems arises not only from combining a variety of building blocks (from simple
Graphical Abstract
Scheme 1: Selectivity levels found in multiple multicomponent reactions. I) Innate selectivity; II) sequentia...
Scheme 2: Indiscriminate double Ugi MCR upon pyridine-2,6-dicarboxylic acid.
Scheme 3: Representative examples of MCR-polymer synthesis. A) Biginelli HTS of polymers; B) Passerini;- C) U...
Scheme 4: Concept of multicomponent macrocyclization.
Scheme 5: Supramolecular structures out of MMCR macrocyclizations.
Scheme 6: Macrocyclization by MMCRs. A) Staudinger MCR; B) boronic-imine MCR.
Scheme 7: Selective Sequential MMCRs. A and B) MCRs involving terephthalaldehyde; C) Multiple GBB processes w...
Scheme 8: Biased substrates for selective MMCRs.
Scheme 9: The Union concept. A) Asinger–Ugi combination; B) Passerini–Ugi/azide from anthranilic acid; C) Pas...
Scheme 10: Relevant examples of consecutive MCRs exploiting the Union Concept. A) Petasis-Ugi combination; B) ...
Scheme 11: Selective MMCRs featuring FGs with distinct reactivity along the sequence. A) Synthesis of aminomet...
Scheme 12: High order MMCRs. A) Ugi/Ugi–Smiles 7C combination; B) imidazoline-N-cyanomethylamide-Ugi union lea...
Scheme 13: Consecutive Ugi 4CR-deprotection–Ugi 4CR strategy towards A) PNA oligomers and B) peptidic tetrazol...
Scheme 14: Sequential Ugi 4CR-deprotection access to cyclopeptoids.
Scheme 15: Stepwise access to 6-aminopenicillanic acid derivative through an Asinger, deprotection, Joullié ap...
Scheme 16: A triple MCR-deprotection approach affording anticancer peptidomimetics.
First synthesis of cryptands with sucrose scaffold
- Patrycja Sokołowska,
- Michał Kowalski and
- Sławomir Jarosz
Beilstein J. Org. Chem. 2019, 15, 210–217, doi:10.3762/bjoc.15.20
- Patrycja Sokolowska Michal Kowalski Slawomir Jarosz Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland 10.3762/bjoc.15.20 Abstract Cryptands with sucrose scaffold, an unknown class of such derivatives, were prepared from the readily available 2,3,3
- ’,4,4’-penta-O-benzylsucrose and 1’,2,3,3’,4,4’-hexa-O-benzylsucrose. Keywords: cryptands; macrocyclization; sucrose; Introduction The design and synthesis of macrocyclic receptors is one of the main challenges of supramolecular chemistry [1][2]. These artificial systems exhibit interesting properties
- material for the preparation of cryptands containing a sucrose platform, a completely new class of such derivatives. This goal can be achieved by introduction of an additional macrocyclic unit connecting both terminal positions as shown in Figure 2. The direct connection of both CH2–OH groups (route a in
Graphical Abstract
Figure 1: Macrocyclic derivatives with sucrose scaffold.
Figure 2: Strategy to sucrose cryptands with additional macrocyclic unit.
Scheme 1: a) 50% NaOH, Bu4NHSO4, 74%; b) NaI, acetone, 95%; c) Na2CO3, ACN, 80 °C, 24 h, 33%.
Figure 3: A concept for synthesis of a cryptand from penta-O-benzylsucrose (2).
Scheme 2: a) MsCl, Et3N, DMAP, DCM, −78 °C to rt.; b) Na2CO3, KI, ACN, reflux.
Scheme 3: a) AllBr, TBAB, PhMe, 50% NaOH, 50 °C, 18 h, 94%; b) i. O3, DCM, −78 °C; ii. NaBH4, DCM, MeOH, rt, ...
Scheme 4: a) 50% NaOH, Bu4NHSO4, 58%; b) NaI, acetone, 95%; c) Na2CO3, ACN, 80 °C, 24 h, 45.5%.
A three-armed cryptand with triazine and pyridine units: synthesis, structure and complexation with polycyclic aromatic compounds
- Claudia Lar,
- Adrian Woiczechowski-Pop,
- Attila Bende,
- Ioana Georgeta Grosu,
- Natalia Miklášová,
- Elena Bogdan,
- Niculina Daniela Hădade,
- Anamaria Terec and
- Ion Grosu
Beilstein J. Org. Chem. 2018, 14, 1370–1377, doi:10.3762/bjoc.14.115
- titration; 1,3,5-triazine; Introduction Cryptands with C3-symmetric aromatic reference groups are exciting targets, on the one hand due to the challenges encountered in their synthesis and on the other due to their ability (macrobicyclic effect [1]) to form supramolecular assemblies with cations, anions or
- neutral guests, e.g., aromatic molecules [2][3][4][5][6]. The supramolecular architectures involving cryptands (including metallomacrocycles) and aromatic guests are targeted for investigations of aromatic–aromatic contacts [7][8] and for various applications in molecular electronics [9][10]. The recently
- reported cage-box [11] is able to complex a plethora of aromatic compounds (e.g., anthracene, pyrene, perylene), while in the cases of several metallo-based cryptands the formation of layered host–guest supramolecular structures (with many guests in the cavity of the host) were reported [12][13][14][15
Graphical Abstract
Figure 1: Cryptands with 1,3,5-triphenylbenzene (1) and 2,4,6-triphenyl-1,3,5-triazine (2) aromatic reference...
Scheme 1: Synthesis of cryptand 2.
Figure 2: NMR spectra of cryptand 2: top, 1H NMR; bottom, 13C NMR.
Figure 3: Chemical shift changes of the reference signal (belonging to the more deshielded protons of the p-p...
Figure 4: The equilibrium geometry structure of cryptand 2 having 2,4,6-triphenyl-1,3,5-triazine caps.
Figure 5: The equilibrium geometry structures of the cryptand–anthracene (a) and cryptand–pyrene (b) host–gue...
Figure 6: The equilibrium geometry structure of the cryptand 2–1,5-dihydroxynaphthalene host–guest complex.
Figure 7: The inclusion dynamics of the anthracene in the cavity of the cryptand for different constrained di...
Synthesis of a sucrose-based macrocycle with unsymmetrical monosaccharides "arms"
- Karolina Tiara,
- Mykhaylo A. Potopnyk and
- Sławomir Jarosz
Beilstein J. Org. Chem. 2018, 14, 634–641, doi:10.3762/bjoc.14.50
- ). The reduction of the amide functions should lead to amines, which might be used as starting materials for the preparation of, e.g., cryptands 6 (Figure 1). All attempts, however, to reduce 4 to diamine 5 were unsuccessful. We have decided, therefore, to elaborate another method leading to
- , 1487.6857; found, 1487.6971; anal. calcd for C86H100N2O19 (1465.74): C, 70.47; H, 6.88; N, 1.91; found: C, 70.62; H, 6.96; N, 1.84. Possible route to sucrose cryptands 6. Possible route to dienes of type 9. Synthesis of macrocyclic derivative 4. Unsuccessful attempts to amines 12a and 13b. Syntheses of
Graphical Abstract
Scheme 1: Synthesis of macrocyclic derivative 4.
Figure 1: Possible route to sucrose cryptands 6.
Figure 2: Possible route to dienes of type 9.
Scheme 2: Unsuccessful attempts to amines 12a and 13b.
Scheme 3: Syntheses of "elongated" amines 17 and 18.
Scheme 4: Synthesis of macrocycle 25.
Superstructures with cyclodextrins: Chemistry and applications IV
- Gerhard Wenz
Beilstein J. Org. Chem. 2017, 13, 2157–2159, doi:10.3762/bjoc.13.215
- repulsive. The first examples of superstructures formed by attractive intermolecular forces were complexes of crown ethers [1], cryptands [2] and spherands [3], which were recognized by the 1987 Nobel Prize in Chemistry. In addition, inclusion compounds of cyclodextrins (CDs), cyclic oligomers of glucose
Host–guest complexes of mixed glycol-bipyridine cryptands: prediction of ion selectivity by quantum chemical calculations, part V
- Svetlana Begel,
- Ralph Puchta and
- Rudi van Eldik
Beilstein J. Org. Chem. 2013, 9, 1252–1268, doi:10.3762/bjoc.9.142
- Erlangen, Germany 10.3762/bjoc.9.142 Abstract The selectivity of the cryptands [2.2.bpy] and [2.bpy.bpy] for the endohedral complexation of alkali, alkaline-earth and earth metal ions was predicted on the basis of the DFT (B3LYP/LANL2DZp) calculated structures and complex-formation energies. The cavity
- size in both cryptands lay between that for [2.2.2] and [bpy.bpy.bpy], such that the complexation of K+, Sr2+ and Tl3+ is most favorable. While the [2.2.bpy] is moderately larger, preferring Rb+ complexation and demonstrating equal priority for Sr2+ and Ba2+, the slightly smaller [2.bpy.bpy] yields
- more stable cryptates with Na+ and Ca2+. Although the CH2-units containing molecular bars fixed at the bridgehead nitrogen atoms determine the flexibility of the cryptands, the twist angles associated with the bipyridine and glycol building blocks also contribute considerably. Keywords: cryptands; DFT
Graphical Abstract
Figure 1: Structure of [2.2.2] also known as 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane or Kr...
Figure 2: Structures of [2.2.bpy] and [2.bpy.bpy].
Figure 3:
Calculated (RB3LYP/LANL2DZp) structure (C2) for [K ![[Graphic 2]](/bjoc/content/inline/1860-5397-9-142-i3.png?max-width=637&scale=0.295455)
2.2.bpy]+.
Figure 4:
Calculated (RB3LYP/LANL2DZp) structure (C2) for [K 2.bpy.bpy]+.
Figure 5:
Calculated (RB3LYP/LANL2DZp) transition state structures (C2) for [Mg 2.2.bpy]2+ and [Ga 2.2.bpy]...
Figure 6: Comparison of the calculated (RB3LYP/LANL2DZp) M–Npyridine/M–Nsp2 and M–NH3/M–Nsp3 coordinating dis...
Figure 7: Comparison of the calculated (RB3LYP/LANL2DZp) M–OH2 and M–O coordinating distances for [2.2.bpy] (...
Figure 8: Comparison of the calculated (RB3LYP/LANL2DZp) M–Npyridine/M–Nsp2 and M–NH3/M–Nsp3 coordinating dis...
Figure 9: Comparison of the calculated (RB3LYP/LANL2DZp) M–OH2 and M–O coordinating distances for [2.bpy.bpy]...
Scheme 1: Model reaction.
Figure 10:
RB3LYP/LANL2DZp complexation energies for [M 2.2.bpy]m+ according to Scheme 1, plotted against the ionic r...
Figure 11:
RB3LYP/LANL2DZp complexation energies for [M 2.bpy.bpy]m+ according to Scheme 1, plotted against the ionic...
Figure 12:
RB3LYP/LANL2DZp torsion angles CH2–Nsp3–Nsp3–CH2 (a) and (CH2)2–Nsp3–Nsp3–(CH2)2 (b) for [M 2.2.bp...
Figure 13:
RB3LYP/LANL2DZp torsion angle Nsp2–C–C–Nsp2 for [M 2.2.bpy]m+ and [M 2.bpy.bpy]m+ plotted against...
Figure 14:
RB3LYP/LANL2DZp torsion angle O–C–C–O for [M 2.2.bpy]m+ and [M 2.bpy.bpy]m+ plotted against the i...
Figure 15: Reverse development of the calculated torsion angles on the respective cryptate sides for [2.2.bpy]....
Figure 16: Reverse development of the calculated torsion angles on the respective cryptate sides for [2.bpy.bp...
Figure 17: Trend in the preferred ion selectivity of the studied cryptands. Every cryptand family is distingui...
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
- ]. This argument holds for polyether compounds with two podand arms, bibraccial lariat ethers. Bridging the ring with the arm leads to cryptands, bicyclic (10a) or polycyclic (10b) crown ethers [115]. If the moiety is “tricyclic closed” via the two nitrogen atoms, the resulting cryptand 10a permits cation
- encapsulation [116] (Figure 7). On inclusion in the cavity of the cryptand, the guest is shielded by three or more polyether bridges. As a result of this encapsulation, cryptands form more stable complexes than coronands (Ka = 106 for NH4+ in methanol at 25 °C). In addition, solution thermodynamics of amino
- sites. Differences between these types of ligands also show up in the kinetics of complex formation. The conformationally rigid cryptands complex slower than coronands and these in turn are slower than the flexible podands. In contrast to crown ethers, the three dimensional cryptands display peak
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...
