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The sensor platform of zinpyr 4 (ZP4) through pyrrole-for-pyridyl substitution is modified and the effects of this variation on both photophysical and metal-binding properties are evaluated. The utility of aniline-based ZP probes for select biological imaging applications are investigated.

The analysis on the dual fluorescence of phenylpyrrole (PP) and pyrrolobenzonitrile (PBN) in supersonic jets and in cryogenic matrixes is presented. Calculation of the structures of the 1:1 clusters are performed using ab initio, density functional theory (DFT) and molecular mechanics (MM) methods.

New cis-strapped calix[4]pyrrole derivatives and trans-strapped systems bearing isophthalate-derived diamide spacers linked to the tetrapyrrolic core are synthesized and characterized by spectroscopic means. The anion-binding behavior of these receptors was investigated by proton NMR spectroscopy and isothermal titration calorimetry.

A new series of heteroatomic polycyclic fluorophore molecules based on the parent moiety of pyreno [2,1-b] pyrrole is reported. All monomeric pyreno [2,1-b] pyrrole and derivatives are highly emissive in solution.

Multinuclear solid-state NMR and infrared spectroscopy are applied to investigate the host-guest interactions and the nature of the adsorption sites of pyrrole on alkali-exchanged zeolites Y. It is concluded that the main source of basic site heterogeneity comes from the number of aluminum atoms in the six-member rings of the SII site where the alkaline cation is located.

A novel, unnatural base pairs is created between fluorophore and quencher nucleobase analogues during the development of orthogonal extra base pairs for expanding the genetic alphabet. The new unnatural base pair system is suitable for detection methods of target nucleic acid sequences and the genetic alphabet expansion system with the replicable, unnatural fluorophore-quencher base pair is a useful tool for sensing and diagnostic applications.

Nematic liquid crystal cells aligned by conductive polymers, like polyaniline or doped polypyrrole, are used for observing a very fast electro-optic response. The role played in the very fast electro-optic response of the ionic charges built on the interfaces together with the redox processes among the free charges in the polymer-liquid crystal interface is discussed.

The absolute configuration of a key intermediate and that of bis(phenylpyrrolidinonyl)ketone (R,R)-1b are determined by using single-crystal X-ray diffraction and the ee values of the photochemical products with the help of chiral shift reagent (+)-Eu[(tfc).sub.3] and chiral LC-MS/MS. The studies have shown that ca. 70% of the bond forming events have occurred with double memory of chirality, ca. 21% has occurred after rotation of one radical to form the meso product (R,S)-3b and only 9% has occurred after double rotation to form the opposite enantiomer.

The synthesis and electrochemical and photophysical characterization of two isomeric [5,6]-pyrrolidine-[I.sub.h]-[Sc.sub.3]N@[C.sub.80] electron donor-acceptor conjugates containing triphenylamine (TPA) as the donor system. The studies have shown that when the donor is connected to the pyrrolidine nitrogen atom, the resulting dyad has produced a longer liver radical pair than the corresponding 2-substituted isomer for both the [C.sub.60] and [I.sub.h]-[Sc.sub.3]N@[C.sub.80] dyads.

The lowest bandgap, soluble, spray-processable polymer is produced by combining a strong donor, tris(dodecyloxy)phenyl)-dithieno[3,2-b:2',3'-d-pyrrole, with a strong acceptor, 4,8-dithien-2-yl-2[[lambda].sup.4][[delta].sup.2]-benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole. Transmission/absorption spectroscopy on single-walled carbon nanotubes (SWCNTs) and reflectance spectroscopy on gold are used for estimating the optical bandgap.

A regioselective synthetic approach is described for a new series of dibenzo[b,b']thieno[2,3-f:5,4-f']-carbazole (DBTCZ) and its ring-extended derivative diindole[3,2-b:2',3'-h]benzo[1,2-b:4,5-b']bis[1]benzothiophene (DIBBBT). The heteroacenes are fully characterized and their X-ray analysis and optical and electrochemical properties are described.

A series of nonlinear optical (NLO) chromophores are prepared, in which pyrrole moieties are the conjugated bridge. These chromophores have shown similar or enhanced NLO effects and optical behavior when compared to their analogues containing furan or thiophene groups as the bridge.

The electron transfer (ET) reactions from the [S.sub.1] and [S.sub.2] states of pentacoordinated tetrapyrrole macrocycles to the axial ligand of pyrometallic diimide (PI) are studied. The ET from the [S.usb.2] state is found to be faster than that from the [S.sub.1] state.

An improved method for the synthesis of luminescent 2,2'-bipyrroles and 5,5-'diformyl-2,2'-bipyrroles which could be used to access light-emitting devices is reported. The reaction is carried out in the presence of Pd-C and activated metallic zinc as the catalysts in presence of water.

A detailed analysis of the mechanism of photoinduced electron and proton transfer in the planar pyrrole-pyridine hydrogen-bonded system, a potential model of the characteristic ultrafast hydrogen bond photochemistry of DNA base pairs is presented.

New fluorescent molecular sensors for 9-alkylguanines are fabricated by conjugation of 2-acetamido-1,8-naphthyridine with N-Boc-pyrrole, N-Boc-pyreno[2,1-b]pyrrole, or acetanilide moieties through an ethynyl bridge. An additional binding site is provided by the substituent located on the pyrrole or aniline ring to increase the affinity of the receptor molecules and the binding events are monitored by the absorption and fluorescent changes in the visible region.

Two artificial photosynthetic antenna models consisting of a Si phthalocyanine (Pc) bearing two axially attached carotenoid moieties having either 9 or 10 conjugated double bonds are used to illustrate the functions of carotenoids in photosynthetic membranes. The results have suggested the association of either inner- or intramolecular charge-transfer species involving carotenoids during the process of excess energy dissipation in photosystem II.

A study was conducted to explore the intramolecular photochemical addition of pyrrole to the stilbene double bond by changing substituents on the para position of the stilbene moiety. The findings suggest that the reaction of NH transfer is more efficient and more selective if the stilbene moiety is substituted with an electron-withdrawing group.

The synthesis and magnetostructural characterization of two para-nitroxylphenylpyrroles, 1-(4-(N-tert-butyl-N-aminoxyl)phenyl)pyrrole (BP-NPP) and 1-(4-(N-[para-methoxyphenyl]-N-aminoxyl)phenyl)-pyrrole (MNPP) is described. MNPP shows stronger antiferromagnetic exchange interactions that appear to be associated with a 2-D planar mesh of crystallographic nitroxide to nitroxide (N)O...N(O) contacts of 4-0-4.2 angstrom.

Click chemistry is used to construct a library of the pyrrolidine-type asymmetric organocatalysts. Study is conducted to evaluate the clicked organocatalysts in asymmetric Michael addition of ketones to nitroolefins, showing good catalytic activity and stereoselectivity.

Atomic force microscopy (AFM), ultraviolet (UV)-vis-near infrared (NIR) absorption, NIR photoluminescence and Raman spectroscopy are used to demonstrate that single-walled nanotubes can be debundled simply by reducing the nanotube concentration in N-methyl-2-pyrrolidone (NMP) dispersions. The findings reveal that the average bundle diameter decreases with decreasing concentration of 8 x [10.sup.-3] mg/mL.

A novel method toward 'locked' chlorins with increased stability is studied and the chlorin skeleton is assembled in a convergent fashion from two fragments through a porphyrin forming reaction, followed by 1,3-dipolar cycloaddition of azomethine ylides, which are formed in situ. Various approaches toward crucial building blocks, namely 3,4-disubstituted-2,5-diformylpyrroles, are examined.

Polypyrrole (PPy) nanotubes with different diameters were readily fabricated using cylindrical micelle templates in sodium bis(2-thylhexyl) sulfosuccinate (AOT) reverse microemulsions. Raman spectroscopy and ultraviolet (UV)-visible spectroscopy revealed that the PPy nanotubes with smaller diameters had a more extended conjugation length as well as higher oxidation level.

The photophysical properties of meta- and para-cyano N-phenylpyrrole are compared. Both compounds show highly red-shifted and strongly forbidden emission in polar solvents, assigned to a charge transfer state.

The 351.1nm photoelectron spectrum of imidazolide anion is measured. The thermodynamic parameters for imidazole and imidazolyl radical are compared with those for pyrrole and pyrrolyl radical and the effects of the additional N atom in the five-membered ring are discussed.

A new compound with electride characteristics,Li@calix[4]pyrrole, is designed. A new idea and different means for designing and synthesizing high-performance nonlinear optical properties (NLO) materials is revealed.

The poly(vinylpyrrolidone) (PVP)-water solutions of 60-80 wt percent PVP apparently do not freeze when cooled far below the expected freezing point. The large amount of rapidly appearing and disappearing sharp peaks in the small-angle X-ray scattering (SAXS) region was observed confirming their origin.

Plasma polymerization of pyrrole was carried out in the presence and absence of iodine, and the resulting films were characterized by optical and electrical means. Their infrared spectra were very similar to each other, suggesting that iodine was neither bonded in any manner to, nor strongly interacting with, the pyrrole polymer chains.

The description of a new photochemically mediated intramolecular metathesis sequence of pyrroles is presented. The reaction has revealed to proceed through two sequential wavelength-dependent reactions involving [2+2] cycloaddition at 220-280 nm followed by a retro-[2+2] of the resulting cyclobutane at wavelengths longer than this.