Macrocyclic open-chain carbazole receptors for carboxylate binding.

The anion recognition properties of six synthetic acyclic and macrocyclic carbazole-based receptors have been studied by H-NMR as well as with COSMO-RS calculations towards acetate, benzoate, lactate, sorbate and formate. The receptors differed by the number and geometry of hydrogen-bond donor (HBD) sites, the nature and length of the linker(s) between the HBD sites and the cyclic or non-cyclic nature. The binding ability of the receptors is strongly influenced by the structure and steric variables of the receptors and anions.

LogP determination for highly lipophilic hydrogen-bonding anion receptor molecules.

Lipophilicity, usually expressed as octanol-water partition coefficient (logP), is an important property in biomedical research, drug design and technology. However, high logP values of complex hydrogen-bonding molecules are not easy to measure or calculate. Exemplary problematic molecules are prospective active components (ionophores) of polymeric sensor membranes - the working elements of ion-selective electrodes.

Design, synthesis and application of carbazole macrocycles in anion sensors.

Carboxylate sensing solid-contact ion-selective electrodes (ISEs) were created to provide a proof-of-concept ISE development process covering all aspects from in silico ionophore design to functional sensor characterization. The biscarbazolylurea moiety was used to synthesize methylene-bridged macrocycles of different ring size aiming to fine tune selectivity towards different carboxylates. Cyclization was achieved with two separate strategies, using either amide synthesis to access up to -[CH]- macrocycles or acyl halides to access up to -[CH]- macrocycles.