We report on the eligibility of tetraphosphonate resorcinarene cavitands for molecular recognition amino acids. determined crystal structure 13 complexes cavitand Tiiii[H, CH3, CH3] with (1)H NMR and (31)P experiments ITC analysis were performed to probe binding between Tiiii[C3H7, C2H5] or water-soluble counterpart Tiiii[C3H6Py(+)Cl(-), a selection representative The reported studies results allowed us (i) highlight noncovalent interactions involved in event each case; (ii) investigate...

Two novel triptycene quinoxaline cavitands (DiTriptyQxCav and MonoTriptyQxCav) have been designed, synthesized, applied in the supramolecular detection of benzene, toluene, ethylbenzene, xylenes (BTEX) air. The complexation properties two towards aromatics solid state are strengthened by presence moieties at upper rim tetraquinoxaline walls, promoting confinement aromatic hydrocarbons within cavity. were used as fiber coatings for solid-phase microextraction (SPME) BTEX monitoring best...

An easily accessible polyoxomolybdate–calix[4]arene hybrid 1 has been synthesized and applied as a heterogeneous catalyst in the sulfoxidation of thioethers to sulfoxides sulfones under strictly stoichiometric amounts 30% H2O2 CH3CN solvent. This study represents first promising example successful employment calixarenes–polyoxometalate (POM) materials area catalytic oxidations.

The stepwise synthesis of ionizable p-tert-butylcalix[5]arenes 1a·H and 1b·H, featuring a fixed cone cavity endowed with carboxyl moiety at the narrow rim, is described. Single-crystal X-ray analyses have shown that in solid state 1b·H adopt cone-out conformation carboxylic OH group pointing in, toward bottom aromatic cavity, as result three- or two-center hydrogen-bonding pattern between phenolic oxygen atom(s). affinity amines for calix[5]arene derivatives was probed by (1)H NMR...

A combined DOSY and XRD study indicates that a carboxylcalix[5]arene receptor is able to encapsulate α,ω-diamines of appropriate length by means proton-transfer-mediated recognition process followed salt-bridge-assisted bis-endo-complexation.

Negatively charged gemini guests in the presence of a tetracationic host trigger formation self-assembling structures at physiological pH water generating entities HG and H2G type (H = G guest). ITC measurements show that are included via concerted electrostatic hydrophobic interactions adduct is enthalpically driven while capsular entity (H2G) by entropy gain. It shown efficiency capsule influenced number –CH2– units contained spacer spacers with an even methylene groups seem to be best...

A new multicomponent material with nanoporous structure has been synthesized by co-crystallization of a mixture cationic meso-tetrakis(4-N-methylpyridyl)porphyrin (H2T4) and meso-tri(4-N-methylpyridyl)porphyrin (H2T3py) polyanionic 5,11,17,23-tetrasulfonato-25,26,27,28-tetrakis(hydroxylcarbonylmethoxy)calix[4]arene (C4TsTc) in the presence Ni2+ ions. The structural analysis indicates that overall architecture is assembled interpenetrated two-dimensional (2D) meshes where nodes are built up...

The octaanionic 5,11,17,23-tetrasulfonato-25,26,27,28-tetrakis(hydroxycarbonylmethoxy)-calix[4]arene (cone conformation) (C4TsTc) was investigated as a sensor for the biogenic tetracationic polyamine, spermine .(H4Spe4+). Fluorescence titration experiments of water-soluble calixarene with showed formation 2:1 and 1:1 calixarene:spermine complexes in solution. single crystal X-ray diffraction analysis [(NaC4TsTc)4·(H4Spe)7] confirmed species that binds either by partially hosting it inner...

New receptors for the selective binding of monoamine neurotransmitters and trace amine hydrochlorides, as ion pairs, are described.

Two new chiral calix[4]arene-salen ligands 1a,b, based on calix[4]arene platforms in 1,3-alternate conformation, have been prepared by a general synthetic pathway. Their Mn(III) complexes, 3a,b shown fairly good efficiency the asymmetric epoxidation of styrene and substituted styrenes, whereas excellent catalytic activity selectivity were observed with rigid bicyclic alkenes, namely 1,2-dihydro-naphthalene 2,2'-dimethyl-chromene. The higher properties 3a may be ascribed to more inherently...

The synthesis of the larger resorcin[5 and 6]arene macrocycles [5]OMe [6]OMe has been realized by a Lewis acid-catalyzed condensation 1,3-dimethoxy-2-methylbenzene with paraformaldehyde in o-dichlorobenzene as solvent. methoxy-resorcin[5 6]arenes were quantitatively demethylated treatment BBr3 to obtain corresponding free OH groups. X-ray studies showed that solid state both conformation packing are driven C–H···O, C–H···π, π···π interactions.

Sulfonato-calix[n]arenes (sclxn) are promising tools to generate crystalline protein frameworks. We report, for the first time, a lower rim functionalised octa-anionic calix[4]arene (sclx4mc) in complex with proteins. Two crystal structures of sclx4mc bound yeast or horse heart cytochrome c (cytc) described. Highly porous honeycomb tubular assemblies were obtained cytc, respectively. Related frameworks previously sclx8 and sclx6 but not sclx4, suggesting that ligand charge is determining factor.

The coupling of a polycationic Mn(III)-porphyrin, with dinuclear Mn2(II,II)L2 core (HL = 2-{[[di(2-pyridyl)methyl](methyl)amino]methyl}phenol), results in dual Superoxide Dismutase (SOD) and Catalase (CAT) functional analogue, Mn2L2Pn+, enabling detoxification cascade the superoxide anion hydrogen peroxide into benign H2O O2. SOD/CAT artificial manifolds, joined one asset, exhibit peak catalytic performance under physiological conditions, log kcat(O2• –) ≥ 7 kcat(H2O2)/KM 1890. dual-enzyme...

Three novel tetra(thio)ureido dihomooxacalix[4]arene anion receptors (phenylurea 4a, phenylthiourea 4b, and tert-butylurea 4c) were synthesized obtained in the cone conformation solution, as shown by NMR studies. The X-ray crystal structure of 4c is reported. host-guest properties these toward several anions investigated 1H titrations. Phenylurea 4a displayed a very efficient binding spherical F- Cl- anions, linear CN- (log Kass = 3.46, 3.50, 4.02, respectively). In comparison to related...

Tetraureido‐dihomooxacalix[4]arenes ( tert ‐butyl 4a and phenyl 4b ) were synthesised obtained in a partial cone conformation solution the solid state, as confirmed by NMR X‐ray diffraction studies. Their complexation ability towards halides, pseudo‐halides oxoanions was assessed 1 H UV/Vis titrations. Structural energetic insights of phenylurea complexes also using molecular dynamics (MD) simulations. The binding data showed that association constants are strongly dependent on nature...

Co-crystallization of a carboxylcalix[5]arene in the presence n-butylamine afforded corresponding host–guest carboxylate–butylammonium salt-bridged complex as result proton transfer process assisted by second non-ionized calixarene molecule. The crystals isolated consist supramolecular pseudo-dimer which inclusion is connected to formally neutral receptor molecule – hosting solvent aromatic cavity via strong negative charge-assisted H-bond between carboxyl/carboxylate substituents present at...

The different behaviours of Ru(η5-C5H5) and Ru(η5-C5Me5) precatalysts, [Ru(η5-C5R5)(NCMe)(N,N)]PF6 (R = H, Me), in the allylic etherification reaction cinnamyl chloride using phenoxide anion as a nucleophile was considered. N,N ligands are commercial products 1,8-diaminonaphthalene 8-aminoquinoline, their derivatives obtained by alkylation amino nitrogen atoms: alkyl substituents that also bulky chiral C2-symmetric frameworks allow modulation basicity steric demand ligands. Some were...

The biogenic tetraamines, spermine and norspermine, are efficiently encapsulated in the solid state by two molecules of carboxylcalix[5]arene, means a highly regioselective proton-transfer followed bis-endo-cavity inclusion, providing overall-neutral complexes with 70–72% packing coefficient, despite modest affinity shown solution.

A combined XRD and 1H NMR study revealed that two molecules of tetrakis-(tert-butyloxycarbonylmethoxy)-calix[5]arene carboxylic acid are able to efficiently encapsulate α,ω-diaminoalkanes suitable length as a result proton-transfer-mediated recognition. In the case 1,10-diaminodecane 1,11-diaminoundecane, rim-to-rim attractive van der Waals interactions drive formation capsular complexes with packing coefficient close 70%. The calixarene bowls in these capsules seen an eclipsed conformation....

Abstract The synthesis of new imine‐amine and diamine ligands, based on both the atropisomeric ( S a )‐ or R )‐1,1′‐binaphthyl )‐bornyl backbones, incorporating an ethylenediamino spacer, are reported. In addition, analogue ligands in which one chiral arm is replaced by achiral NMe 2 group were synthesized. These N , ‐ligands when coordinated to palladium metal centre form highly enantioselective catalysts for asymmetric allylic alkylation rac ‐2‐acetoxy‐1,3‐diphenylpropene dimethyl...

CF2HCbl, CF3Cbl , and CF3CH2Cbl have been synthesized characterized in solution by 1H NMR UV–vis spectroscopy, their X-ray crystal structures determined using synchrotron radiation. The structure of is reported for the first time, whereas those CF2HCbl are re-examined to obtain more precise structural data. Comparison data obtained with alkylcobalamin analogues, MeCbl EtCbl, indicates that Co–C Co–NB3 bond lengths shorter fluoroalkylcobalamins. fluoroalkylcobalamins previously literature had...