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Julius Rebek - One of the best experts on this subject based on the ideXlab platform.
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rigidified Cavitand hosts in water bent guests shape selectivity and encapsulation
Journal of the American Chemical Society, 2021Co-Authors: Jimin Yang, Yongqing Chen, Pablo Ballester, Julius RebekAbstract:We report the synthesis and characterization of two water-soluble container compounds (Cavitand hosts) with rigidified open ends. One Cavitand uses four (CH2)4's as spacers to bridge the adjacent walls, while another Cavitand uses four CH2CH2OCH2CH2's bridges and features a wider open end. The spacers preorganize the deep Cavitands into vase-like, receptive shapes and prevent their unfolding to the unreceptive kite-like conformation. Cycloalkane guests (C6-C8) and small n-alkanes (C5-C7) form 1:1 complexes with the Cavitands and move freely in the Cavitands' spaces. Hydrophilic compounds 1,4-dioxane, tetrahydrofuran, tetrahydropyran, pyridine, and 1-methylimidazole also showed good binding affinity to the new Cavitands. Longer alkanes (C11-C14) and n-alcohols (C11-C16) are taken up with a -CH3 group fixed at the bottom of the cavity and the groups near the rim in compressed conformations. The methylene bridges appear to divide the Cavitand into a narrow hydrophobic compartment and a broader space with exposure to the aqueous medium. Longer alkane guests (C15-C18), N,N-dimethyldioctylammonium, and dioctylamine induce the formation of capsules (2:1 host:guest complexes). The new Cavitands showed selectivity for p/m-cresol isomers and xylene isomers. The Cavitand with CH2CH2OCH2CH2 bridges bound long-chain α,ω-diols (C13-C15) and diamines in folded, U-shaped conformations with polar functions exposed to the aqueous medium. It was used to separate o-xylene from its isomers by using simple extraction procedures.
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recognition of hydrophilic cyclic compounds by a water soluble Cavitand
Molecules, 2021Co-Authors: Yunhui Wan, Yujie Zhu, Julius RebekAbstract:A water-soluble deep Cavitand bearing amides on the upper rim and trimethyl ammonium groups on the feet was synthesized. The open-ended cavity is stabilized by the intramolecular hydrogen bonds formed between the adjacent amides, and the introduction of trimethylammonium imparts to the Cavitand good solubility in water. The Cavitand exhibits high binding affinity and selectivity to hydrophilic molecules in water. With certain guests, such as cyclohexyl alcohols, amines and acids, the recognition involves the synergistic action of hydrogen bonding with hydrophobic effects. The binding phenomena are interpreted in terms of a fixed solvent cage presented by the host to the guest.
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chalcogenbonding and hydrophobic effects force moleculesinto small spaces
2020Co-Authors: Faizur Rahman, Pablo Ballester, Ioannis D Petsalakis, Giannoula Theodorakopoulos, Demeter Tzeli, Julius RebekAbstract:Supramolecular capsules are desirable containers for the study of molecular behavior in small spaces and offer applications in transport, catalysis, and material science. We report here the use of chalcogen bonding to form container assemblies that are stable in water. Cavitands 1–3 functionalized with 2,1,3-benzoselenadiazole walls were synthesized in good yield from resorcin[4]arenes. The solid-state single-crystal X-ray structure of 3 showed a dimeric assembly cemented together through multiple Se···N chalcogen bonds. Binding of hydrophobic and amphiphilic guests in D2O was investigated by 1H NMR methods and revealed host–guest assemblies of 1:1, 2:1, and 2:2 stoichiometries. Small guests such as n-hexane or cyclohexane assembled as 2:2 capsular complexes, larger guests like cyclohexane carboxylic acid or cyclodecane formed 1:1 Cavitand complexes, and longer linear guests like n-dodecane, cyclohexane carboxylic acid anhydride, and amides created 2:1 capsular complexes. The 2:1 complex of the capsule with cyclohexane carboxylic acid anhydride was stable over 2 weeks, showing that the seam of chalcogen bonds is “waterproof”. Selective uptake of cyclohexane over benzene and methyl cyclohexane over toluene was observed in aqueous solution with the capsule. Hydrophobic forces and hydrogen-bonding attractions between guest molecules such as 3-methylbutanoic acid stabilized the assemblies in the presence of the competing effects of water. The high polarizability and modest electronegativity of Se provide a capsule lining complementary to guest C–H bonds. The 2,1,3-benzoselenadiazole walls impart an unusually high magnetic anisotropy to the capsule environment, which is supported by density functional theory calculations.
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mono epoxidation of α ω dienes using nbs in a water soluble Cavitand
Organic chemistry frontiers, 2019Co-Authors: Venkatachalam Angamuthu, Julius Rebek, Manuel Petroselli, Faizur RahmanAbstract:Water-soluble host molecules offer a range of environments to their guests. Polar functions of guests are exposed to the medium while hydrophobic groups are generally buried in the containers and hidden from reagents in solution. Here, we apply these preferences to convert α,ω-dienes to epoxy alkenes using Cavitands as reaction vessels. Reaction of one end of a diene with NBS in water gives a bromohydrin that binds in the Cavitand with the hydroxyl exposed and the remaining alkene buried. Treatment with base converts the bromohydrin to an epoxide. The reaction sequence provided up to 84% yields of monoepoxides from symmetrical dienes separated by 4 to 10 methylene groups. With 1,4-diisopropenyl benzene, a nearly quantitative yield of the monoepoxide was obtained. The application should be general for converting symmetrical hydrophobic guests to unsymmetrical, amphiphilic ones.
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Cavitands: capture of cycloalkyl derivatives and 2-methylisoborneol (2-MIB) in water
2019Co-Authors: Hai-na Feng, Manuel Petroselli, Xing-hua Zhang, Julius RebekAbstract:Cycloalkyl derivatives such as halides and alcohols are commonly encountered in chemical synthesis and in the environment, yet chemical methods for their sensing are limited. Here we develop a sensor – a deep Cavitand – on a preparative scale. It makes host-guest complexes with cycloalkyl halides and other derivatives with compact conformations in aqueous medium. Detection of 2-methylisoborneol, a common drinking water pollutant, is possible at low concentrations by NMR methods. The gram-scale synthesis of the Cavitand opens new possibilities for its future application in water purification.
Enrico Dalcanale - One of the best experts on this subject based on the ideXlab platform.
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probing the structural determinants of amino acid recognition x ray studies of crystalline ditopic host guest complexes of the positively charged amino acids arg lys and his with a Cavitand molecule
Molecules, 2018Co-Authors: Giovanna Brancatelli, Enrico Dalcanale, Roberta Pinalli, Silvano GeremiaAbstract:Crystallization of tetraphosphonate Cavitand Tiiii[H, CH₃, CH₃] in the presence of positively charged amino acids, namely arginine, lysine, or histidine, afforded host-guest complex structures. The X-ray structure determination revealed that in all three structures, the fully protonated form of the amino acid is ditopically complexed by two tetraphosphonate Cavitand molecules. Guanidinium, ammonium, and imidazolium cationic groups of the amino acid side chain are hosted in the cavity of a phosphonate receptor, and are held in place by specific hydrogen bonding interactions with the P=O groups of the Cavitand molecule. In all three structures, the positively charged α-ammonium groups form H-bonds with the P=O groups, and with a water molecule hosted in the cavity of a second tetraphosphonate molecule. Furthermore, water-assisted dimerization was observed for the Cavitand/histidine ditopic complex. In this 4:2 supramolecular complex, a bridged water molecule is held by two carboxylic acid groups of the dimerized amino acid. The structural information obtained on the geometrical constrains necessary for the possible encapsulation of the amino acids are important for the rational design of devices for analytical and medical applications.
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Cavitand decorated silicon columnar nanostructures for the surface recognition of volatile nitroaromatic compounds
ACS Omega, 2018Co-Authors: Cristina Tudisco, Enrico Dalcanale, Chiara Massera, Alessandro Motta, Roberta Pinalli, Tahnie Barboza, Antonino E Giuffrida, Guglielmo G CondorelliAbstract:Nanocolumnar Si substrates (porous silicon (PSi)) have been functionalized with a quinoxaline-bridged (EtQxBox) Cavitand in which the quinoxaline moieties are bonded to each other through four ethylendioxy bridges at the upper rim of the cavity. The receptor, which is known to selectively complex aromatic volatile organic compounds (VOCs) even in the presence of aliphatic compounds, has been covalently anchored to PSi. The larger surface area of PSi, compared to that of flat substrates, allowed one to study the recognition process of the surface-grafted receptors through different techniques: Fourier-transform infrared spectroscopy, thermal desorption, and X-ray photoelectron spectroscopy. The experiments proved that surface-grafted Cavitands retain the recognition capability toward aromatic VOCs. In addition, the affinities of EtQxBox for various aromatic compounds (i.e., benzene, toluene, nitrobenzene, and p-nitrotoluene) have been studied combining density functional theory computations and thermal desorption experiments. Computational data based on the crystal structures of the complexes indicate that this Cavitand possesses a higher affinity toward aromatic nitro-compounds compared to benzene and toluene, making this receptor of particular interest for the detection of explosive taggants. The results of computational studies have been validated also for the surface-grafted receptor through competitive recognition experiments. These experiments showed that EtQxBox-functionalized PSi can recognize nitrobenzene in the presence of a significant excess of aromatic vapors such as benzene (1:300) or toluene (1:100).
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Fluorinated Tetraphosphonate Cavitands
MDPI AG, 2018Co-Authors: Alessandro Pedrini, Federico Bertani, Enrico DalcanaleAbstract:Two synthetic protocols for the introduction of fluorine atoms into resorcinarene-based Cavitands, at the lower and upper rim, respectively, are reported. Cavitand 1, bearing four fluorocarbon tails, and Cavitand 2, which presents a fluorine atom on the para position of a diester phosphonate phenyl substituent, were synthesized and their complexation abilities toward the model guest sarcosine methyl ester hydrochloride were evaluated via NMR titration experiments. The effect of complexation on the 19F NMR resonance of the probe is evident only in the case of Cavitand 2, where the inset of the cation-dipole and H-bonding interactions between the P=O bridges and the guest is reflected in a sizable downfield shift of the fluorine probe
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Cavitand-Decorated Silicon Columnar Nanostructures for the Surface Recognition of Volatile Nitroaromatic Compounds
2018Co-Authors: Cristina Tudisco, Enrico Dalcanale, Chiara Massera, Alessandro Motta, Roberta Pinalli, Tahnie Barboza, Antonino E Giuffrida, Guglielmo G CondorelliAbstract:Nanocolumnar Si substrates (porous silicon (PSi)) have been functionalized with a quinoxaline-bridged (EtQxBox) Cavitand in which the quinoxaline moieties are bonded to each other through four ethylendioxy bridges at the upper rim of the cavity. The receptor, which is known to selectively complex aromatic volatile organic compounds (VOCs) even in the presence of aliphatic compounds, has been covalently anchored to PSi. The larger surface area of PSi, compared to that of flat substrates, allowed one to study the recognition process of the surface-grafted receptors through different techniques: Fourier-transform infrared spectroscopy, thermal desorption, and X-ray photoelectron spectroscopy. The experiments proved that surface-grafted Cavitands retain the recognition capability toward aromatic VOCs. In addition, the affinities of EtQxBox for various aromatic compounds (i.e., benzene, toluene, nitrobenzene, and p-nitrotoluene) have been studied combining density functional theory computations and thermal desorption experiments. Computational data based on the crystal structures of the complexes indicate that this Cavitand possesses a higher affinity toward aromatic nitro-compounds compared to benzene and toluene, making this receptor of particular interest for the detection of explosive taggants. The results of computational studies have been validated also for the surface-grafted receptor through competitive recognition experiments. These experiments showed that EtQxBox-functionalized PSi can recognize nitrobenzene in the presence of a significant excess of aromatic vapors such as benzene (1:300) or toluene (1:100)
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redox switchable thianthrene Cavitands
Synthesis, 2016Co-Authors: Wen Jie Ong, Enrico Dalcanale, Federico Bertani, Timothy M SwagerAbstract:A redox activated vase-to-kite conformational change is reported for a new resorcinarene-based Cavitand appended with four quinoxaline-fused thianthrene units. In its neutral state, the thianthrene-containing Cavitand was shown by 1H NMR to adopt a closed vase conformation. Upon oxidation the electrostatic repulsion among the thianthrene radical cations promotes a kite conformation in the thianthrene-containing Cavitand. The addition of acid produced a shoulder feature below 300 nm in the Cavitand’s UV-Vis spectrum that we have assigned to the vase-to-kite conformation change. UV-Vis spectroelectrochemical studies of the Cavitand revealed a development of a similar shoulder peak consistent with the oxidation-induced vase-to-kite conformation change. To support that the shoulder peak is diagnostic for a vase-to-kite conformation change, a model molecule constituting a single quinoxaline wall of the Cavitand was synthesized and studied. As expected UV-Vis spectroelectrochemical studies of the Cavitand arm did not display a shoulder peak below 300 nm. The oxidation-induced vase-to-kite conformation is further confirmed by the distinctive upfield shift in 1H chemical shift of the methine signal.
Francois Diederich - One of the best experts on this subject based on the ideXlab platform.
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experimental and computational study of bodipy dye labeled Cavitand dynamics
Journal of the American Chemical Society, 2014Co-Authors: Igor Pochorovski, Bernd W Schweizer, Tim Knehans, Daniel Nettels, Astrid M Muller, Amedeo Caflisch, Benjamin Schuler, Francois DiederichAbstract:Understanding the distance distribution and dynamics between moieties attached to the walls of a resorcin[4]arene Cavitand, which is switchable between an expanded kite and a contracted vase form, might enable the use of this molecular system for the study of fundamental distance-dependent interactions. Toward this goal, a combined experimental and molecular dynamics (MD) simulation study on donor/acceptor borondipyrromethene (BODIPY) dye-labeled Cavitands present in the vase and kite forms was performed. Direct comparison between anisotropy decays calculated from MD simulations with experimental fluorescence anisotropy data showed excellent agreement, indicating that the simulations provide an accurate representation of the dynamics of the system. Distance distributions between the BODIPY dyes were established by comparing time-resolved Forster resonance energy transfer experiments and MD simulations. Fluorescence intensity decay curves emulated on the basis of the MD trajectories showed good agreement with the experimental data, suggesting that the simulations present an accurate picture of the distance distributions and dynamics in this molecular system and provide an important tool for understanding the behavior of extended molecular systems and designing future applications.
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fluorophore functionalized and top covered resorcin 4 arene Cavitands
Israel Journal of Chemistry, 2012Co-Authors: Igor Pochorovski, Francois DiederichAbstract:This review describes our recent developments in the field of resorcin[4]arene Cavitands. We present the syntheses of Cavitands bearing pyrene, anthracene, and BODIPY dyes as fluorophores on the Cavitand walls. These systems have been used to examine the conformational switching process between the closed vase and the open kite forms that are characteristic for this class of Cavitands. In a second research direction, we prepared top-covered resorcin[4]arene-based, switchable container molecules, and investigated their binding and switching properties.
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cycloalkane and alicyclic heterocycle complexation by new switchable resorcin 4 arene based container molecules nmr and itc binding studies
Chemistry: A European Journal, 2011Co-Authors: Jens Hornung, Bernd W Schweizer, Daniel Fankhauser, Laura D Shirtcliff, Antonia Praetorius, Francois DiederichAbstract:The synthesis and structural characterization of novel, "molecular basket"-type bridged Cavitands is reported. The resorcin[4] arene-based container molecules feature well-defined cavities that bind a wide variety of cycloalkanes and alicyclic heterocycles. Association constants (K(a)) of the 1: 1 inclusion complexes were determined by both (1)H NMR and isothermal titration calorimetry (ITC). The obtained Ka values in mesitylene ranged from 1.7 x 10(2)m(-1) for cycloheptane up to 1.7 x 10(7) m(-1) for morpholine. Host-guest complexation by the molecular baskets is generally driven by dispersion interactions, C similar to H center dot center dot center dot pi interactions of the guests with the aromatic walls of the cavity, and optimal cavity filling. Correlations between NMR-based structural data and binding affinities support that the complexed heterocyclic guests undergo additional polar C-O center dot center dot center dot C=O, N-H center dot center dot pi, and S center dot center dot center dot pi interac-tions. The first crystal structure of a Cavitand-based molecular basket is reported, providing precise information on the geometry and volume of the inner cavity in the solid state. Molecular dynamic (MD) simulations provided information on the size and conformational preorganization of the cavity in the presence of encapsulated guests. The strongest binding of heterocyclic guests, engaging in polar interactions with the host, was observed at a cavity filling volume of 63 +/- 9%.
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fret studies on a series of bodipy dye labeled switchable resorcin 4 arene Cavitands
Chemistry: A European Journal, 2010Co-Authors: Igor Pochorovski, Benjamin Breiten, Bernd W Schweizer, Francois DiederichAbstract:A series of borondipyrro-methane (BODIPY)-dye-labeled resor cin[4] arene Cavitands 1-4 with different lengths of oligo(phenylene-ethynylene) spacers between the dyes and the macrocyclic rim has been synthesized. Their switching behavior from the "vase" to "kite" conformations in bulk solution was examined by both variable-temperature (VT) NMR and fluorescence spectroscopy. Both VT-NMR and VT fluorescence resonance energy transfer (FRET) experiments showed that Cavitands 1-4 undergo vase-to-kite switching at low temperatures. Acid-triggered switching to the kite conformation was observed by fluorescence spectroscopy. Quantitative evaluation of the FRET data led to the determination of the Forster radius R-0 = 37 angstrom for the BODIPY-dye FRET pair and an average Cavitand opening angle alpha = 16 degrees in the vase conformation.
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resorcin 4 arene Cavitand based molecular switches
Advanced Functional Materials, 2006Co-Authors: Vladimir A Azov, Francois Diederich, Andrew Beeby, Martina Cacciarini, Andrew G Cheetham, Markus Frei, James K Gimzewski, Volker Gramlich, Bert Hecht, Bernhard JaunAbstract:147 Resorcin[4]arene Cavitands with four quinoxaline bridges are a family of macrocycles that adopt, at elevated temperature, a contracted, vase-type conformation, capable of guest inclusion, whereas at low temperature they switch to an expanded, kite-type conformation with a large flat surface. The present investigations lay the foundation for the use of such dynamic Cavitands as miniaturized mechanical grippers for supramolecular construction at the single-molecule level. New vase–kite switching modes, stimulated by pH changes or stoichiometric metal-ion complexation, have been discovered and monitored by 1 H NMR and optical absorption spectroscopy. The solid-state geometries of the two states have been revealed by X-ray crystallography, and the kinetics and thermodynamics of the switching processes in solution as well as their solvent dependency has been investigated in great detail. Monolayers of the Cavitand in the vase form have been studied by scanning tunneling microscopy at molecular resolution; conformational switching is also observed in Langmuir monolayers at the air/water interface. Synthetic protocols have been developed for preparation of partially and asymmetrically bridged resorcin[4]arene Cavitands, which are also shown to undergo conformational switching. These synthetic advances pave the way to new, dynamic molecular receptors for steroids, tetrathiofulvalene-bridged grippers with the potential to undergo electrochemically induced conformational switching, and systems with greatly extended, rigid cavity walls functionalized at the termini by dipyrrometheneboron difluoride dyes. The latter Cavitands are shown by fluorescence resonance energy transfer to undergo geometrically precisely defined motions between a contracted (≈7 A linear extension) and a strongly expanded (≈7 nm linear extension) state.
Igor Pochorovski - One of the best experts on this subject based on the ideXlab platform.
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experimental and computational study of bodipy dye labeled Cavitand dynamics
Journal of the American Chemical Society, 2014Co-Authors: Igor Pochorovski, Bernd W Schweizer, Tim Knehans, Daniel Nettels, Astrid M Muller, Amedeo Caflisch, Benjamin Schuler, Francois DiederichAbstract:Understanding the distance distribution and dynamics between moieties attached to the walls of a resorcin[4]arene Cavitand, which is switchable between an expanded kite and a contracted vase form, might enable the use of this molecular system for the study of fundamental distance-dependent interactions. Toward this goal, a combined experimental and molecular dynamics (MD) simulation study on donor/acceptor borondipyrromethene (BODIPY) dye-labeled Cavitands present in the vase and kite forms was performed. Direct comparison between anisotropy decays calculated from MD simulations with experimental fluorescence anisotropy data showed excellent agreement, indicating that the simulations provide an accurate representation of the dynamics of the system. Distance distributions between the BODIPY dyes were established by comparing time-resolved Forster resonance energy transfer experiments and MD simulations. Fluorescence intensity decay curves emulated on the basis of the MD trajectories showed good agreement with the experimental data, suggesting that the simulations present an accurate picture of the distance distributions and dynamics in this molecular system and provide an important tool for understanding the behavior of extended molecular systems and designing future applications.
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fluorophore functionalized and top covered resorcin 4 arene Cavitands
Israel Journal of Chemistry, 2012Co-Authors: Igor Pochorovski, Francois DiederichAbstract:This review describes our recent developments in the field of resorcin[4]arene Cavitands. We present the syntheses of Cavitands bearing pyrene, anthracene, and BODIPY dyes as fluorophores on the Cavitand walls. These systems have been used to examine the conformational switching process between the closed vase and the open kite forms that are characteristic for this class of Cavitands. In a second research direction, we prepared top-covered resorcin[4]arene-based, switchable container molecules, and investigated their binding and switching properties.
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fret studies on a series of bodipy dye labeled switchable resorcin 4 arene Cavitands
Chemistry: A European Journal, 2010Co-Authors: Igor Pochorovski, Benjamin Breiten, Bernd W Schweizer, Francois DiederichAbstract:A series of borondipyrro-methane (BODIPY)-dye-labeled resor cin[4] arene Cavitands 1-4 with different lengths of oligo(phenylene-ethynylene) spacers between the dyes and the macrocyclic rim has been synthesized. Their switching behavior from the "vase" to "kite" conformations in bulk solution was examined by both variable-temperature (VT) NMR and fluorescence spectroscopy. Both VT-NMR and VT fluorescence resonance energy transfer (FRET) experiments showed that Cavitands 1-4 undergo vase-to-kite switching at low temperatures. Acid-triggered switching to the kite conformation was observed by fluorescence spectroscopy. Quantitative evaluation of the FRET data led to the determination of the Forster radius R-0 = 37 angstrom for the BODIPY-dye FRET pair and an average Cavitand opening angle alpha = 16 degrees in the vase conformation.
Simone Mosca - One of the best experts on this subject based on the ideXlab platform.
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preparative scale and convenient synthesis of a water soluble deep Cavitand
Nature Protocols, 2016Co-Authors: Simone Mosca, Julius RebekAbstract:Cavitands are established tools of supramolecular chemistry and molecular recognition, and they are finding increasing application in sensing and sequestration of physiologically relevant molecules in aqueous solution. The synthesis of a water-soluble, deep Cavitand is described. The route comprises six (linear) steps from commercially available precursors, and it relies on the fourfold oligomeric cyclization reaction of resorcinol with 2,3-dihydrofuran that leads to the formation of a shallow resorcinarene framework; condensation with aromatic panels, which deepens the hydrophobic binding cavity; construction of rigid urea functionalities on the upper rim; and the introduction of the water-solubilizing methylimidazolium groups on the lower rim. Late intermediates of the synthesis can be used in the preparation of congener Cavitands with different properties and applications, and a sample of such a synthetic procedure is included in this protocol. Emphasis is placed on scaled-up reactions and on purification procedures that afford materials in high yield and avoid chromatographic purification. This protocol provides improvements over previously described procedures, and it enables the preparation of sizable amounts of deep Cavitands: 7 g of a water-soluble Cavitand can be prepared from resorcinol in 13 working days.
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a deep Cavitand templates lactam formation in water
Journal of the American Chemical Society, 2015Co-Authors: Simone Mosca, Yang Yu, Jesse V Gavette, Kangda Zhang, Julius RebekAbstract:Cyclization reactions are common processes in organic chemistry and show familiar patterns of reaction rates vs ring size. While the details vary with the nature of bond being made and the number of unsaturated atoms, small rings typically form quickly despite angle strain, medium size rings form very slowly due to internal strains, and large rings form slowly (when they form at all) because fewer and less probable conformations bring the ends of the substrate together. High dilution is commonly used to slow the competing bi- and higher molecular processes. Here we apply Cavitands to the formation of medium size lactams from ω-amino acids in aqueous (D2O) solution. The Cavitands bind the amino acids in folded conformations that favor cyclization by bringing the ends closer together. Yields of a 12-membered lactam are improved 4.1-fold and 13-membered lactam 2.8-fold by the Cavitand template. The results open possibilities for moving organic reactions into water even when the processes involve dehydration.
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recognition and sequestration of ω fatty acids by a Cavitand receptor
Proceedings of the National Academy of Sciences of the United States of America, 2015Co-Authors: Julius Rebek, Simone Mosca, Dariush AjamiAbstract:One of the largest driving forces for molecular association in aqueous solution is the hydrophobic effect, and many synthetic receptors with hydrophobic interiors have been devised for molecular recognition studies in water. Attempts to create the longer, narrower cavities appropriate for long-chain fatty acids have been thwarted by solvophobic collapse of the synthetic receptors, giving structures that have no internal spaces. The collapse generally involves the stacking of aromatic panels onto themselves. We describe here the synthesis and application of a deep Cavitand receptor featuring “prestacked” aromatic panels at the upper rim of the binding pocket. The Cavitand remains open and readily sequesters biologically relevant long-chain molecules—unsaturated ω-3, -6, and -9 fatty acids and derivatives such as anandamide—from aqueous media. The Cavitand exists in isomeric forms with different stacking geometries and n-alkanes were used to characterize the binding modes and conformational properties. Long alkyl chains are accommodated in inverted J-shaped conformations. An analogous Cavitand with electron-rich aromatic walls was prepared and comparative binding experiments indicated the role of intramolecular stacking in the binding properties of these deep container molecules.