Inhibition of histamine mediated responses by Mirabilis jalapa: confirming traditional claims made about antiallergic and antiasthmatic activity

The roots of Mirabilis jalapa are used traditionally in allergic skin disorders and asthma. The effect of an ethanol:acetone (1:1) extract of the roots of M. jalapa was studied for antihistaminic activity using a guinea pig tracheal chain preparation and clonidine-induced mast cell granulation in mice. Its antiallergic activity was evaluated using milk-induced eosinophilia and albumin-induced paw oedema in mice. The extract (0.5 mL of 100 mg mL(-1)) inhibited histamine-induced guinea pig tracheal chain contractions non-competitively. The extract (100 or 200 mg kg(-1) i.p.) inhibited milk-induced eosinophilia, albumin-induced paw oedema and protected mast cells against clonidine-induced granulation. The study justified the folkloric use of M. jalapa in the treatment of allergic diseases and asthma.     

Comparison of binding behavior for molecularly imprinted polymers prepared by hierarchical imprinting or Pickering emulsion polymerization

The aim of this study was the evaluation of the binding performances and selectivity of molecularly imprinted beads prepared toward several penicillins (i) by hierarchical bulk polymerization in the pores of template‐grafted silica microbeads (hMIPs) and (ii) by Pickering emulsion polymerization in the presence of template‐decorated silica nanobeads (pMIPs). 6‐Aminopenicillanic acid was chosen as the common fragmental mimic template. Both approaches produced micron‐sized polymeric beads with good recognition properties toward the target ligands whereas the selectivity pattern appeared quite different. The polymer prepared by the Pickering emulsion approach showed binding properties similar to imprinted beads prepared by hierarchical approach. Equilibrium binding constants changed their values from 0.1–0.2 × 10⁶ (hMIPs) to 0.2–0.6 × 10⁶ M^?1 (pMIPs), while the binding site densities changed from 3.7–4.8 (hMIPs) to 0.3–0.55 μmol/g (pMIPs). Compared to the hierarchical polymerization, Pickering emulsion polymerization represents a more practical approach when a template mimic needs to be used.     

Synthesis of new chiral cyclic 1,2-diamines and their evaluation as catalysts for enantioselective Diels-Alder reactions

The synthesis of new, enantiomerically pure cyclic 1,2-diamine structures was realized through a zinc promoted coupling of chiral bis-imines easily prepared starting from a chiral biphenyl dicarboxylic acid. The catalytic properties of such novel compounds were preliminarily studied; the trifluoroacetate salts of these chiral 1,2-diamines were shown to be able to catalyze the Diels-Alder reaction between cyclopentadiene and α,β-unsaturated aldehydes with good exo stereoselectivity and enantioselectivities up to 71%.     

Intermolecular electronic excitation transfer in a confined space: a first-principles study.

The process of intermolecular electronic excitation transfer (EET) in a monodimensional supramolecular arrangement of molecules in confined space has been modelled and investigated by means of first-principles molecular dynamics simulations. The chosen model system consists of a wire of chlorine molecules hosted in the noncrossing channels of the zeolite bikitaite. The time evolution of the system in its first excited singlet state has been described by the restricted open shell Kohn-Sham formalism. Simulation results have highlighted that excitation, initially localized on a guest molecule, is transferred to an adjacent moiety in the molecular wire on the picosecond scale via a collision-induced Dexter-type short range EET. Analysis of the modifications of the electronic structure of the system brought about by EET has given insight into the microscopic details of the process.     

An original route to newly-functionalized indoles and carbazoles starting from the ring-opening of nitrothiophenes

The multifaceted behavior of nitrobutadienes deriving from the initial ring-opening of nitrothiophenes finds a further clear-cut example in their Michael-type acceptor reactivity towards indole. Thus, depending on the starting diene, either newly-functionalized indoles or carbazoles are produced, the latter as the result of an appealing double (intermolecular + intramolecular) Michael-type addition to a nitrovinylic moiety. The outcome encompasses motifs for both mechanistic and synthetic interest in the field of heterocycles endowed with possible pharmacological activity.     

Interface properties of ionic liquids containing metal ions: features and potentialities

Interfaces and surfaces are the regions where important events happen: catalysis, molecular recognition, charge transfer, polymerization, and many other critical processes take place at the boundary between one medium and another. In this article we discuss the interface (liquid/air) properties of ionic liquids (ILs) containing dissolved metal ions with the aim to show the possibility to use metal salts to transform ILs and their surfaces into engineered liquid supports to apply in material sciences, separation procedures or to use as optical devices.     

Access to 2,3-diaryl-4-nitrothiochroman S,S-dioxides from 3-nitrobenzo[b]thiophene

The base-induced cyclization of (E)-2-aryl-1-[2-(benzylsulfonyl)phenyl]-1-nitroethenes to polysubstituted thiochroman S,S-dioxides exhibits a diastereoselectivity that can be oriented towards a selected isomer by means of appropriate adjustments of the experimental conditions. The interest of such a result also rests on the promising pharmacological activity of the products, whose structure encompasses different well-acknowledged pharmacophores. A conformational ¹H NMR investigation, backed by molecular-mechanics calculations, has also been accomplished.     

Synthesis and conformational analysis of a novel carbohydrate-fused bis-crown ether: crown-CyPLOS

A novel sugar-based macrocycle consisting of a phosphate-linked 12-membered disaccharide ring (cyclic phosphate-linked oligosaccharide, CyPLOS), fused to two 18-crown-6 ether residues, is here described. The synthesis of the target compound has been accomplished in 23% overall yield for 11 reaction steps, exploiting phosphoramidite chemistry for the dimerization and a classical phosphotriester methodology for the cyclization reaction. NMR-based conformational analysis studies have been carried out on the fully deprotected macrocycle, showing a characteristic arched-structure with C₂-symmetry.     

Reaction of singlet oxygen with thioanisole in ionic liquid-acetonitrile binary mixtures

A study of the reaction of thioanisole with singlet oxygen in different ionic liquid-acetonitrile binary mixtures has shown that ILs are able to accelerate the thioanisole sulfoxidation when used as additives. With imidazolium ILs, the maximum efficiency is reached at x(IL) ～ 0.1-0.2, whereas for the pyrrolidinium IL a plateau is reached. These results are discussed in terms of the ILs' tendency to form ionic aggregates and of differences in sulfoxidation reaction mechanism.     

Apteniols A-F, oxyneolignans from the leaves of Aptenia cordifolia

Investigation of the organic extract of Aptenia cordifolia leaves revealed six new oxyneolignans named apteniols A-F. The structures were determined by means of spectroscopic methods. The C₆C₃ units are linked by an oxygen atom at C4-C4′ or C4-C2′ and they are dihydrophenylpropanoid acid units. Their effects on germination and growth of Lactuca sativa L. have been studied in the range concentration 10⁻⁴-10⁻⁷ M.