Enantioselective Receptor Research Articles

Steroidal ureas as enantioselective receptors for an N-acetyl alpha-amino carboxylate.

[reaction: see text] Cholic acid has been elaborated into three regioisomeric bis-carbamoylureas, which have been investigated as enantioselective receptors for N-acetyl phenylalanine. L/D selectivities, peaking at 5:1, have been determined by a sensitive and rapid MS-based extraction method that should be generalizable to related systems.

A highly enantioselective receptor for N-protected glutamate and anomalous solvent-dependent binding properties.

The development of enantioselective receptors continues to be a challenging endeavor for supramolecular chemists, and enantioselective recognition of biologically relevant molecules in competitive solvents is particularly demanding.[1] Although numerous receptors have been developed for dicarboxylic acids and dicarboxylates,[2] only a few enantioselective receptors for chiral dicarboxylic acids (in the neutral diprotonated form) have been described,[3] and very few examples of enantioselective receptors for chiral dicarboxylates have been reported.[4] We recently described an acyclic monothiourea receptor 1a, which bound a range of N-protected amino acid carboxylate salts with modest enantioselectivity.[5] Building on this work, we have now prepared macrocyclic receptor 2, which features two thiourea moieties flanked by carboxypyridines and separated by a chiral diamine. The receptor was designed to produce a chiral pocket for dicarboxylates by forming up to eight hydrogen-bonding interactions with the carboxylate oxygen atoms and intramolecular hydrogen bonding with the pyridine unit to help preorganize[6] the receptor (Scheme 1). Binding measurements, by NMR titration and isothermal

A Highly Enantioselective Receptor for N ‐Protected Glutamate and Anomalous Solvent‐Dependent Binding Properties

A Highly Enantioselective Receptor for <i>N</i> ‐Protected Glutamate and Anomalous Solvent‐Dependent Binding Properties

Preparation and self-assembly of chiral porphyrin diads on the gold electrodes of quartz crystal microbalances: a novel potential approach to the development of enantioselective chemical sensors.

Porphyrin diad 1 was synthesized by reaction of the acyl chloride of porphyrin 2 and trans-1,2-dithiane-4,5-diol. The Co complex of this diad was studied as a potential enantioselective receptor for chiral recognition in solution and in the solid state. In solution both enantiomers of limonene induce significant changes in the visible and circular dichroism (CD) spectra of [Co2(1)], while a different behavior is observed in the case of the enantiomeric pair of trans-1,2-diaminocyclohexane. A different efficiency of [Co2(1)] chiral recognition is obtained for these compounds, with a remarkable degree of enantiodiscrimination observed in the case of limonene. Self-assembled monolayers of [Co2(1)] were deposited onto the gold electrodes of quartz crystal microbalances to be used as sensing materials of nanogravimetric sensors operating in the gas phase. The enantiodiscrimination properties of these sensors towards the enantiomeric pairs of chiral analytes have been studied. While in the case of analytes bearing donor ligand atoms we did not observe a remarkable enantioselectivity, a significant degree of chiral discrimination was observed in the case of limonene; this result is particularly encouraging for the potential development of enantioselective chemical sensors for use in an array configuration.

ChemInform Abstract: Steroidal Guanidines as Enantioselective Receptors for N‐Acyl α‐Amino Acids. Part 1. 3α‐Guanylated Carbamates Derived from Cholic Acid.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Steroidal guanidines as enantioselective receptors for N-acyl α-amino acids. Part 1. 3α-Guanylated carbamates derived from cholic acid

Receptors 5–11, bearing guanidinium, carbamate and (in some cases) other functional groups, were synthesized from cholic acid 1. These cations were shown to extract chiral carboxylate anions from aqueous buffer into chloroform with significant enantioselectivities. The most successful receptors bore two carbamate substituents and achieved, in the best cases, ratios (L:D) of 7–10:1 for a series of five N-acetyl α-amino acids.

ChemInform Abstract: Chiral Recognition of 1,1′‐Bi‐2‐naphthol Enantiomers by Twisted Amidine Derivatives: Rational Design of a Highly Enantioselective Receptor

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Chiral recognition of 1,1′-bi-2-naphthol enantiomers by twisted amidine derivatives: Rational design of a highly enantioselective receptor

Abstract Clarification of the molecular structures of diastereomeric complexes relevant to the enantioselective dual N···HO binding between the chiral C 2 amidine derivative (S,S)- 1 and 1,1′-bi-2-naphthol 2 in CDCl 3 afforded the structural factor determining the sense of observed enantioselection. This insight into chiral recognition was successfully applied to the design of a new twisted dual hydrogen bond acceptor (S,S)- 3 that exhibited a higher level of enantioselectivity toward 2 .

A New Ruthenium(II) Chiroporphyrin Containing a Multipoint Recognition Site: Enantioselective Receptor of Chiral Aliphatic Alcohols.

Methyl and ester substituents which sit on the porphyrin ring define one groove on each face near the ruthenium center of the chiroporphyrin. Ethanol binds within one of the clefts by multipoint interaction involving OH···O and CH···O hydrogen bonds in addition to Ru−O coordination. Enantioselective binding of chiral aliphatic alcohols is observed, and the recognition of the (R)-enantiomer of 2-octanol is explained by van der Waals contacts of its n-hexyl substituent which fits nicely in the groove.

ChemInform Abstract: Practical Synthesis of a Highly Enantioselective Receptor (I) for Peptides.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Practical synthesis of a highly enantioselective receptor for peptides

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPractical synthesis of a highly enantioselective receptor for peptidesShawn D. Erickson, Julian A. Simon, and W. Clark StillCite this: J. Org. Chem. 1993, 58, 6, 1305–1308Publication Date (Print):March 1, 1993Publication History Published online1 May 2002Published inissue 1 March 1993https://doi.org/10.1021/jo00058a005RIGHTS & PERMISSIONSArticle Views284Altmetric-Citations42LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (505 KB) Get e-Alerts Get e-Alerts

ChemInform Abstract: The 6‐Deoxy‐6‐N‐histamino‐β‐cyclodextrincopper(II) Complex, a New Enantioselective Receptor for Aromatic Amino Acids.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Demonstration of a receptor in Torpedo synaptic vesicles for the acetylcholine storage blocker L-trans-2-(4-phenyl[3,4-3H]-piperidino) cyclohexanol.

Transport and storage of acetylcholine by purified Torpedo electric organ synaptic vesicles is blocked by the drug L-trans-2-(4-phenylpiperidino)cyclohexanol (AH-5183). This study sought evidence of a specific receptor for the drug. Highly tritiated L-trans-2-(4-phenyl [3,4-3H] piperidino)-cyclohexanol (L-[3H] AH5183) was synthesized. An excess of nonradioactive L-isomer competed with L-[3H]AH5183 for binding to purified Torpedo synaptic vesicles whereas nonradioactive D-isomer did so poorly. Dissociation of bound L-[3H]AH5183 was first order with a rate constant at 23 degrees C of 0.23 +/- 0.03 min-1, and association was too rapid to study. At equilibrium the amount of L-[3H]AH5183 bound at saturation varied in different vesicle preparations, but in one typical preparation specific binding of 181 +/- 15 pmol L-[3H]AH5183 per mg of synaptic vesicle protein was observed with a dissociation constant of 34 +/- 6 nM. Neither acetylcholine nor choline compete effectively with L-[3H]AH5183 for binding. The evidence suggests that about 3.7 +/- 0.3 enantioselective receptors for L-[3H]AH5183 are typically present in each cholinergic synaptic vesicle, and the L-AH5183 binding site does not recognize acetylcholine.