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Crystal growth of 2-(3,4,5-triphenylphenyl)acetic acid (1) from acetonitrile yields a monosolvate, C26H2O2·CH3CN, of the space group P1. In the crystal, the title molecule adopts a conformation in which the three phenyl rings are arranged in a paddlewheel-like fashion around the central arene ring and the carboxyl residue is oriented nearly perpendicular to the plane of this benzene ring. Inversion-symmetric dimers of O-H...O-bonded molecules of 1 represent the basic supramolecular entities of the crystal structure. These dimeric molecular units are further linked by C-H...O-C bonds to form one-dimensional supramolecular aggregates running along the crystallographic [111] direction. Weak Cary1-H...N interactions occur between the molecules of 1 and acetonitrile. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C33H33N9, the tripodal molecule exists in a conformation in which the substituents attached to the central arene ring are arranged in an alternating order above and below the ring plane. The three benzotriazolyl moieties are inclined at angles of 88.3 (1), 85.7 (1) and 82.1 (1)° with respect to the mean plane of the benzene ring. In the crystal, only weak molecular cross-linking involving C—H···N hydrogen bonds is observed. [ABSTRACT FROM AUTHOR]

The title compound, C18H21N3O3, was prepared from 1,3,5-benzenetricarbonyl trichloride and cyclopropylamine. Its crystal structure was solved in the monoclinic space group P21/c. In the crystal, the three amide groups of the molecule are inclined at angles of 26.5 (1), 36.9 (1) and 37.8 (1)° with respect to the plane of the benzene ring. The molecules are linked by N—H···O hydrogen bonds, forming two-dimensional supramolecular aggregates that extend parallel to the crystallographic ab plane and are further connected by C—H···O contacts. As a result of the supramolecular interactions, a propeller-like conformation of the title molecule can be observed. [ABSTRACT FROM AUTHOR]

Crystallization of 5-nonanoyl-8-hydroxyquinoline in the presence of InCl3 in acetonitrile yields a dinuclear InIII complex crystallizing in the space group P1. In this complex, [In2(C18H22NO2)2Cl4(H2O)2], each indium ion is sixfold coordinated by two chloride ions, one water molecule and two 8-quinolinolate ions. The crystal of the title complex is composed of two-dimensional supramolecular aggregates, resulting from the linkage of the Owater—H...O C and Owater—H...Cl hydrogen bonds as well as bifurcated Carene—H...Cl contacts. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C26H36N2O4, the tripodal molecule exists in a conformation in which the substituents attached to the central arene ring are arranged in an alternating order above and below the ring plane. The heterocyclic unit is inclined at an angle of 79.6 (1)° with respect to the plane of the benzene ring. In the crystal, the molecules are connected via N—H⋯O bonds, forming infinite supramolecular strands. Interstrand association involves weak C—H⋯O and C—H⋯π interactions, with the pyridine ring acting as an acceptor in the latter case. [ABSTRACT FROM AUTHOR]

Introduction: The design of carbohydrate-binding agents (artificial carbohydrate receptors) that enable selective and effective biomimetic recognition via noncovalent interactions is aimed either at a better understanding of natural recognition phenomena or at various potential applications in medicine and other fields. Although very interesting artificial receptors have been developed, the exact prediction of the receptor selectivity remains a challenge. Results and Methods: A molecular architecture based on a 1,3,5-substituted 2,4,6-triethylbenzene backbone bearing two aminopyridine- or aminopyrimidine-based recognition units and a purine moiety, which acts as both a hydrogen bonding site and a bridging component for the incorporation of additional substituents, has proved to be very useful for the development of effective carbohydrate-binding agents. This type of compounds has the ability to bind suitable carbohydrates through combined noncovalent interactions, where CH···π interactions can be formed on both faces of the carbohydrate substrate. The successful syntheses of the target compounds can be realized by the use of microwave irradiation and sealed tubes. The performed binding studies included ¹ H NMR spectroscopic titrations and measurements by isothermal titration calorimetry. Conclusion: The new compounds were developed as artificial receptors especially for carbohydrates with an all-equatorial substitution pattern and have the ability to predictably form strong 1:1 complexes with a suitable substrate. The use of the purine moiety in the construction of carbohydrate receptors with a 1,3,5-substituted 2,4,6-triethylbenzene backbone has proved to be a very promising approach. The possibilities for structural variation of this molecular architecture are manifold. As a result, a wide range of compounds can be synthesized to perform extensive studies on the relationships between structure and binding efficiency [ABSTRACT FROM AUTHOR]

New phenylacetic acid derivatives with potentially valuable biological activities and the ability to act as starting materials for various functionalizations have been prepared by a multi-step synthesis. Starting from 2,6-dibromo-4-methylaniline, the synthetic route involves the construction of the basic aromatic structure (3,4,5-triphenyltoluene) (two steps), followed by its conversion into 2-[(3,4,5-triphenyl)phenyl]acetic acid and derivatives (up to five steps). Based on this multi-step synthesis, five compounds not previously reported in the literature were synthesized; the literature-known 3,4,5-triphenyltoluene was synthesized for the first time in the manner described. This synthesis is applicable for the preparation of numerous new representatives of this class of compounds. [ABSTRACT FROM AUTHOR]

Various functional groups have been considered as acceptors for halogen bonds, but the oxime functionality has received very little attention in this context. In this study, we focus on the analysis of the hydrogen and halogen bond preferences observed in the crystal structures of 5-halogeno-1H-isatin-3-oximes. These molecules can be involved in various non-covalent interactions, and the competition between these interactions has a decisive influence on their self-organization. In particular, we were interested to see whether the crystal structures of 5-halogeno-1H-isatin-3-oximes, especially bromine- and iodine-substituted ones, are characterized by the presence of halogen bonds formed with the oxime functionality. The oxime group proved its ability to compete with the other strong donor and acceptor sites by participating in the formation of cyclic hydrogen-bonded heterosynthons oxime∙∙∙amide and Ooxime∙∙∙Br/I halogen bonds. [ABSTRACT FROM AUTHOR]

In the crystal structures of the formamide monosolvate (1a) and the n-propanol/H2O solvate/hydrate (1b) of the title compound, C38H50N4O3 (1), the tripodal host molecule adopts a conformation in which the substituents attached to the central benzene ring are arranged in an alternating order above and below the ring plane. As a result of the different nature of the involved guest species, the crystal components in 1a create a three-dimensional supramolecular architecture, while the crystal structure of 1b consists of two-dimensional supramolecular aggregates extending parallel to the crystallographic ab plane. [ABSTRACT FROM AUTHOR]

New representatives of 2,4,7‐trisubstituted 9,9‐dialkyl‐9H‐fluorenes were prepared and used for crystallographic investigations as well as initial binding studies towards metal ions and carbohydrates. The binding studies, which included 1H NMR spectroscopic titrations and fluorescence measurements, demonstrated the ability of the tested fluorene‐based compounds to act as complexing agents for ionic and neutral substrates. Depending on the nature of the subunits of the fluorene derivatives, "turn on" or "turn off" fluorescent chemosensors can be developed. Compounds composed of 4,6‐dimethylpyridin‐2‐yl‐aminomethyl moieties have the potential to be used as sensitive "turn‐on" chemosensors for some metal ions. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C30H50N4O4, the two bis­(hy­droxy­eth­yl)amino moieties and the 2,4-di­methyl­pyridinyl­amino unit of the mol­ecule are located on one side of the central benzene ring, while the ethyl substituents are oriented in the opposite direction. The dihedral angle between the planes of the aromatic rings is 73.6 (1)°. The conformation of the mol­ecule is stabilized by intra­molecular O--H⋯O (1.86-2.12 Å) and C--H⋯N (2.40, 2.54 Å) hydrogen bonds. Dimers of inversion-related mol­ecules represent the basic supra­molecular entities of the crystal structure. They are further connected via O--H⋯O hydrogen bonding into undulating layers extending parallel to the crystallographic bc plane. Inter­layer inter­action is accomplished by weak C--H⋯π contacts. [ABSTRACT FROM AUTHOR]

The complex of 2,4,6-tri­ethyl-1,3,5-tris­[(4-methyl-1H-indazol-1-yl)meth­yl]­benz­ene with ammonium hexa­fluorophosphate, C39H42N6·NH4+·PF6-, crystallizes in the monoclinic space group P21 with two mol­ecules of the receptor, two NH4+ and two PF6- ions in the asymmetric unit. In each of the complexes the ammonium ion resides in the cavity of the receptor mol­ecule and is fixed in its position by three N--H⋯N bonds, while the remaining hydrogen atom of the cation acts as a bifurcated binding site for N--H⋯F bonding to the counter-anion. The crystal is composed of one-dimensional supra­molecular aggregates extending along the a-axis direction. [ABSTRACT FROM AUTHOR]

The investigation is conducted on the crystal structures of a new series of alpha,beta-unsaturated ketoximes, 8-14, carrying the terminal 4-pyridinyl, 3-pyridinyl, or 4-quinolinyl subunit by X-ray structural analysis. The result reveals that alpha,beta-unsaturated ketoximes carrying a terminal pyridine or quinoline subunit are versatile building blocks for supramolecular syntheses.

Describing the syntheses, crystal structures, and binding properties of new acyclic pyridine-based receptors 4, 8-12, 14, and 15 toward monosaccharides. The results showed that acyclic receptors containing amino- or amidopyridine binding subunits perform effective recognition of carbohydrates through multiple interactions.