Artificial Receptors Inspired by Crystal Structures of Complexes Formed between Acyclic Receptors and Monosaccharides: Design, Syntheses, and Binding Properties

Abstract

The binding motifs found in the crystal structures of complexes formed between artificial receptors and monosaccharides, reported previously by our group, have inspired us to design new macrocyclic and acyclic receptors, which were expected to form strong 1:1 complexes with monosaccharides, in particular with β-glucosides, through participation in the formation of CH-π interactions and hydrogen bonds with the sugar substrate. As first representatives of these compounds we have prepared the macrocycles 8-12 and the acyclic molecules 13-16, incorporating two central triethylbenzene units. The new compounds had been designed to bind monosaccharides via interactions of both central benzene rings with the sugar CH groups. Initial binding studies have confirmed the expected favorable binding capabilities of the macrocyclic compounds and indicated interesting binding properties of the acyclic analogues.

Native Mannose‐Dominant Extraction by Pyridine–Phenol Alternating Oligomers Having an Extremely Efficient Repeating Motif of Hydrogen‐Bonding Acceptors and Donors

“…[1] So far,v arious kinds of synthetic hosts for saccharides have been developed, and many of them utilize hydrogen-bondingf unctional groups targeting hydroxyl groups of saccharide guests. [2][3][4][5] However,o nly af ew of the many synthetic architectures have been effective for strong recognition of saccharides, specificallynative ones. Thisdifficulty is likely to result primarily from the three-dimensional complexity of the saccharide structures,w hich should require sophisticated designo fs ynthetic hosts.…”

Syntheses of Acyclic and Macrocyclic Compounds Derived from 9,9‐Diethylfluorene (Part I)

“…The synthesis of the last mentioned compound from the analogue bearing two 1,3-dioxo-1,3dihydro-2H-isoindol-2-yl groups (compound 22) is also considered in this work. Both the acyclic and the macrocyclic fluorene-based compounds have among other things the potential to act as artificial receptors for different ionic and neutral substrates in the analogy to the known receptors possessing a benzene [10][11][12][13][14] or biphenyl [15] core. For example, some representatives of the acyclic and macrocyclic compounds consisting of the central benzene or biphenyl unit were found to be effective receptors for such substrates as ammonium ions, [11] ion pairs [12] or carbohydrates.…”

Fluorene Derivatives Bearing Halogenomethyl Groups: Synthesis, Molecular Structures, and Halogen/Hydrogen Bonding Patterns in the Crystalline State

“…In this paper we describe the synthesis and crystal structures of 2,4,7‐tris(halogenomethyl)‐9,9‐diethylfluorenes 1–3 (Figure ), which represent valuable precursors for the synthesis of a wide range of compounds consisting of a fluorene scaffold. In particular, the fluorenes 1–3 are promising starting materials for the construction of fluorene‐based artificial receptors in analogy to the preparation of the benzene‐based systems (see Figure ), such as the powerful acyclic and macrocyclic carbohydrate receptors, which have been developed by us during the last few years.…”