Crystalline Nanoparticles of Water-Soluble Covalent Basket Cages (CBCs) for Encapsulation of Anticancer Drugs.

We herein describe the preparation, assembly, recognition characteristics, and biocompatibility of novel covalent basket cage CBC-11, composed of four molecular baskets linked to four trivalent aromatic amines through amide groups. The cage is tetrahedral in shape and similar in size to small proteins (M =8637 g/mol) with a spacious nonpolar interior for accommodating multiple guests. While 24 carboxylates at the outer surface of CBC-11 render it soluble in aqueous phosphate buffer (PBS) at pH=7.

Closed Aromatic Tubes-Capsularenes.

In this study, we describe a synthetic method for incorporating arenes into closed tubes that we name capsularenes. First, we prepared vase-shaped molecular baskets 4-7. The baskets comprise a benzene base fused to three bicycle[2.

Dissipative Formation of Covalent Basket Cages.

Living systems use chemical fuels to transiently assemble functional structures. As a step toward constructing abiotic mimics of such structures, we herein describe dissipative formation of covalent basket cage CBC 5 by reversible imine condensation of cup-shaped aldehyde 2 (i.e.

A double-decker cage for allosteric encapsulation of ATP.

In this work, we describe the preparation of double-decker cage [1-H] comprising two binding pockets, each with three ammonium and three amide hydrogen bonding sites. This novel host possesses a high affinity for trapping two molecules of ATP in an allosteric fashion, with both experiments and theory suggesting the synergistic action of charged hydrogen bonds and π-π stacking in the encapsulation.

Picking on Carbonate: Kinetic Selectivity in the Encapsulation of Anions.

Supramolecular hosts bind to inorganic anions at a fast rate and select them in proportion with thermodynamic stability of the corresponding [anion⊂host] complexes, forming in a reversible manner. In this study, we describe the action of hexapodal capsule 1 and its remarkable ability to select anions based on a large span of rates by which they enter this host. The thermodynamic affinity of 1 toward eighteen anions extends over eight orders of magnitude (0 View Article and Find Full Text PDF

Pyrene-Functionalized Fluorescent Nanojars: Synthesis, Mass Spectrometric, and Photophysical Studies.

Nanojars are a class of supramolecular coordination complexes based on pyrazolate, Cu, and OH ions that self-assemble around highly hydrophilic anions and serve as efficient anion binding and extraction agents. In this work, the synthesis, characterization, and photophysical properties of pyrene-functionalized fluorescent nanojars are presented. Three pyrene derivatives, 4-(pyren-1-yl)pyrazole (H), 4-(5-(pyren-1-yl)pent-4-yn-1-yl)pyrazole (H), and 4-(3-(pyrazol-4-yl)propyl)-1-(pyren-1-yl)-1,2,3-triazole (H), and the corresponding nanojars were synthesized and characterized using nuclear magnetic resonance spectroscopy and mass spectrometry.

Molecular Recognition of Nerve Agents and Their Organophosphorus Surrogates: Toward Supramolecular Scavengers and Catalysts.

Nerve agents are tetrahedral organophosphorus compounds (OPs) that were developed in the last century to irreversibly inhibit acetylcholinesterase (AChE) and therefore impede neurological signaling in living organisms. Exposure to OPs leads to a rapid development of symptoms from excessive salivation, nasal congestion and chest pain to convulsion and asphyxiation which if left untreated may lead to death. These potent toxins are prepared on a large scale from inexpensive staring materials, making it feasible for terrorist groups or states to use them against military and civilians.

A Hexapodal Capsule for the Recognition of Anions.

We herein describe the preparation, characterization, and recognition characteristics of novel hexapodal capsule composed of two benzenes joined by six hydrogen bonding (HB) groups to encircle space. This barrel-shaped host was obtained by reversible imine condensation of hexakis-aldehyde and hexakis-amine in the presence of oxyanions or halides acting as templates. Fascinatingly, capsule includes 18 HB donating (C-H and N-H) and 12 HB accepting groups (C═O and C═N) surrounding a binding pocket (78 Å).

A highly diastereoselective synthesis of deep molecular baskets.

We describe a preparative method for directing Mizoroki-Heck cyclotrimerization of enantioenriched bromonorbornenes into molecular baskets having increasingly deeper and extendable aromatic cavities. Such diastereoselective cyclotrimerizations of the bromo-olefinic substrates resulted from prevalent β migratory insertions without the formation of palladacycle intermediate(s). The facile access to multigram quantity of a new series of basket-like hosts clears the way for creating novel supramolecular materials for storage, sequestration and catalysis.

A Molecular Capsule with Revolving Doors Partitioning Its Inner Space.

Covalent capsule 1 was designed to include two molecular baskets linked with three mobile pyridines tucked into its inner space. On the basis of both theory (DFT) and experiments (NMR and X-ray crystallography), we found that the pyridine "doors" split the chamber (380 Å ) of 1 so that two equally sizeable compartments (190 Å ) became joined through a conformationally flexible aromatic barrier. The compartments of such unique host could be populated with CCl (88 Å ; PC=46 %), CBr (106 Å ; 56 %) or their combination CCl /CBr (PC=51 %), with thermodynamic stabilities ΔG° tracking the values of packing coefficients (PC).