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An extensive study on the generation and reactivity of azafulvenium methides is presented, together with details of a study of the thermolysis of N-vinyl- and C-vinylpyrroles. The synthesis and X-ray structure of a new 6-oxocyclopenta[b]pyrrole derivative is also reported.

A detailed anion binding study of the fluorinated calix[n]pyrrole family, including octamethylcalix[4] pyrrole as a control system, using isothermal titration calorimetry is reported. Anion binding studies in the solid state, involving single-crystal X-ray diffraction analyses of the chloride and acetate anion complexes of octafluorocalix[4]pyrrole and decafluorocalix[5]pyrrole, respectively, confirmed the expected hydrogen bond interactions between the pyrrolic NH protons and the bound anions.

A histidine-coordinating metal complex substituted with methoxypyrrole amino acids (MOPAS) as a peptide beta-sheet bonder shows high affinity for a H2N-His-Leu-Leu-Val-Phe-OMe pentapeptide in DMSO solution. Within the complex, a beta-sheet conformation is induced into the pentapeptide by weak intra-assembly interactions with the MOPAS units.

Symmetric and nonsymmetric diarylethenes with a 2,5-dihydropyrrole bridging unit is prepared and the photochromic properties are investigated. In polar solvents, photochromic diarylethenes with 2,5-dihydropyrrole bridging units produce 3,4-diarylpyrrole derivatives instead of the ring-closing isomer of diarylethenes with UV light irradiation.

The condensation of 1,3-bis-silyl enol ethers with 1-azido-2,2-dimethoxyethane and subsequent reductive cyclization allowed an efficient regio- and diastereoselective synthesis of a variety of 2-alkylidene-4-methoxypyrroldines. The TiCl4 -mediated condensation of simple silyl enol ethers with alpha-azidoketals is reported.

N-methylfulleropyrrolidine bis-adducts constitute a series of isomers whose polarity is extremely similar and do not display particularly polar functional groups. The isolation and characterization of bis-and tris-adducts of fulleropyrrolidine derivatives are reported.

Three different procedures are compared to obtain properly substituted divinyl ketones in which one of the double bonds is embedded in a five-membered heterocyclic structure and therefore suitable to produce cyclopenta-fused pyrrole, derivatives by the acid-catalyzed Nazarov reaction. A convergent procedure base on the umpolung to a vinylstannane gave acceptable yields of the divinyl ketone, which forms a key intermediate in the synthesis of roseophilin.

Chiral 3-acryloyl-2-vinyl-substituted 1,3-perhydrobenzoxazines derived from (--)-8-aminomenthol participate in an ene reaction leading to 3,4-disubstituted pyrrolidinone derivates with excellent diastereoselectivity. The cycloadducts were transformed into enantiopure 3,4-disubstituted pyrrolidines after elimination of the chiral adjuvant.

A nucleophilic attack by the ene-amino carbon of 3-dimethylaminopropenoates at the terminal carbon of the azo-ene system of 1,2-diaza-1,3-butadienes is observed. In tetrahydrofuran at 65 degree C, this attack produced 1-aminopyrrolines with a high degree of cis-stereoselectivity by means of an unusual zwitterionic adduct intermediate followed by intramolecular ring closure.

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.

The polypyrrole/poly(vinyl sulfonate) (PPy/PVS) films in acetonitrile containing 0.1 M LiC1O(sub 4) were studied by cyclic voltammetry. The result was confirmed by 'ex situ' energy-dispersive X-ray analysis of the films and the increase and shift of the voltammetric cycles indicated a restructuring of the polymeric chains with consecutive scans.

Spin-trapping properties of nitrone 5-carbamoyl-5-methyl-1-pyrroline N-oxide (AMPO) was demonstrated. The suitability of AMPO as a spin trap to study radical production in aqueous system was confirmed.

Structure of the unusual anthelmintic pyrrolobenzoxazine terpenoid natural product CJ-12662 was confirmed by X-ray crystallography and partial synthesis from 2-chloronitrobenzene. The pyrrolobenzoxazine moiety was synthesized using dye-sensitized photooxygenation of a tryptophan derivative.

Reporting on the torquoselectivity in the cyclization of 2-substituted five-membered azacycle and 2- and 4-substituted six-membered oxacycle derivatives. The reaction is highly diastereoselective with 2-substituted five-membered lactam derivatives 11a and 11b and leads to cis disubstituted cyclopenta-fused pyrrolines 13a and 13b, respectively.

Taking advantage of the access to quaternary stereogenic centers through stereospecific addition of nucleophiles at C-5, starting from silyloxypyrrole 7, to achieve an efficient and highly diastereoselective synthesis of marine sponge metabolite dysibetaine, as well as deoxy and 4-epi analogues.

The reactivity of chiral alpha-amidoalkylphenyl sulfones with other nucleophilic reagents and the application of the obtained adducts to the first enantioselective synthesis of (-)-1-amino-pyrrolizidine is reported. The optically active pyrrolizidine is a pivotal intermediate for the synthesis of alkaloids endowed of interesting biological activity.

The electroactivity of electrogenerated polypyrrole films is degraded by applying consecutive anodic potential pulses. The charge consumed during each degradation step is calculated by the difference between the degradation ad the control chronoamperograms.

The synthesis of JH-37, as well as its ability to selectively bind to inverted CCAAT boxes (ICB)2 and ICB3 is described. Binding of JH-37 to multiple ICB sites in the topoisomerase II alpha promoter is an ideal test for this strategy.

A simple sonochemical route is developed for the crystal growth of uniform silver nanoplates and ringlike gold nanocrystals in an N, N-dimethylformamide solution. The platelike structures are generated from the selective growth on different crystal planes in the poly (vinylpyrrolidone) and the ultrasonic-assisted Ostwald ripening processes.

The diversity of mechanisms for enantiodiscrimination and of bond types that can be formed makes Pd-catalyzed asymmetric allylic alkylation, a powerful step for simplification of synthetic strategy to complex molecular targets. A wide range of different classes of compounds including chromanes, polyhydrofurans and amino acids are used and novel synthetic strategies emerge, which provide short efficient asymmetric syntheses.

An enantiomerically pure N-phenethylnorborn-5-en-endo-2,3-dicarboxyimide, with a 2-exo-hydroxy-10-bornylsulfinyl group as a chiral auxiliary was used to develop an enantiodivergent synthesis of C-10b-substituted pyrrolo[2,1-a]isoquinolines. The key reactions obtained from diastereoselective parham cyclization and alpha-amidoalkylation reactions are highlighted.

The reactivity of C-vinylpyrroles and their application as building blocks (pyrrole moiety carriers) in the synthesis of more complex pyrrole compounds is reviewed. The study illustrates the substantial advances achieved in the field of the chemistry of C-vinylpyrroles, especially those with functional groups.

A strategy to electrodeposit polypyrrole (PPy) or roughened silver substrates, accomplished by a triangular-wave oxidation-reduction cycle (ORC) for three scans in an aqueous solution containing 0.1 N KCl is studied. Different view on how Raman spectroscopy has proved to be an effective means to evaluate the structure situation of PPy in various states.

A model with atomic detail of the polypyrrole/water system is simulated in both the oxidized (charged) and reduced (uncharged) polymer. From the simulated trajectories, macroscopic properties, such as the polypyrrole density in its reduced state and polymer swelling after oxidation, are simulated.

A small library of H-pin polyamides with variable aliphatic bridge lengths ((CH2)(sub n)), where n=4-8, connecting a central Py/Py pair is prepared via parallel synthesis with Ru-catalyzed alkene metathesis on solid phase as a complexity-generating cross-linking reaction. DNA binding affinities and sequence specificities were analyzed for each member of the library to determine the optimum linker length.

The first attempt of enzyme catalysis in ionic liquid containing pyrrolidinium cations is described. Lipase activity and stability is investigated in dialkylimidazolium and pyrrolidinium-based ionic liquids with a variety of anions.

The view that the large red shifts seen in the UV-visible adsorption bands of peripherally crowded nonplanar porphyrins are the result of nonplanar deformations of the macrocycle is challenged by the suggestion that the red shifts arise from substituent-induced changes in the macrocycle bond length and bond angles. Results of studies suggest that UV-visible band shifts of tetrapyrroles in proteins are potentially useful indicators of changes in nonplanarity provided other structural and electronic factors can be eliminated.

A polyamide ligand is created (ImHpPyPy-beta-Dp), which segregates in a dimeric sequence among the four applicable basic pair levels in the smallest groove. This is an important identification for the design of DNA linking drugs, since such identification can be applicable in the large groove of DNA.

A novel water-soluble guanidiniocarbonyl pyrrole carboxylate zwitterion is synthesized. Its self-association in aqueous solutions is examined and it is found that zwitterion forms extremely stable 1:1 dimers.

A study reported the data on the inhibition of bovine plasma amine oxidase (BPAO) by a family of 3-aryl-3-pyrrolines (aryl=substituted phenyl, 1- naphthyl, 2-naphthyl), with the 4-methoxy-3- nitrophenyl analogue being the most potent. The development of highly selective inhibitors is studied, and such inhibitors aid in unraveling the physiological functions of the various mammalian quinine-dependent amine oxidases, as well as potential drug candidates.

The hybrid materials constituted by polypyrrole doped with the polyoxometalate (POM) anion [SiCr(H2O)W11O39](super 5-) are electrogenerated from acetonitrile solutions. The electrochemical behavior of the hybrid films is studied by cyclic voltammetry in three different electrolytes formed by two anions and two cations dissolved in acetonitrile.

The report was prepared to synthesize and characterize a new super-extended cavity tetraacetylcalix[4] pyrrole derivative and x-ray crystal structures of complexes bound to flouride and acetonitrile were obtained. The modeling studies suggested that the lower position of the fluoride in the complex allows it to maximize the strength of the hydrogen bonds with the pyrrolic NH groups.

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.

An unprecedented rearrangement of the framework of the bilindione that occurs as a direct consequence of the pi-coordination of the palladium is reported. This process involves the cleavage of the Pd-Pd and Pd-C bonds, oxidation of palladium, migration of nitrogen atom form one carbon to another and introduction of an oxygen atom (from water) not necessarily in this particular sequence.

The synthetic sequence of polysubstituted pyrroles is believed to be advantageous for the one-post preparation of both tri and tetrasubstituted pyrroles. The method provides at least four points of diversification, and it allows the introduction of ester, amide, sulfone, and various aryl and heterocyclic substituents.

Experimental and theoretical gas-phase studies of several noncovalent complexes of elementary molecules of biological interest are presented. The comparison provides a test of the validity of the employed methods.

The potentiostatic synthesis and microgravimetric kinetics of hybrid materials polypyrrole/PW12O40(super 3-) are investigated. The results show that the mechanism of the electropolymerization process does not change in significant way when the conditions of synthesis are changed.

The results of nanosecond laser photolysis and steady-state photolysis at 77 K are compared and it is concluded that the lowest excited singlet state undergoes rapid intramolecular proton transfer forming an N-ylide compound. At room temperature, no formation of N-ylide compound as a stable compound can be observed due to its rapid reversion to 1-piperidino- or 1-pyrrolidino-anthraquinone.

The synthesis of ()-nemonapride from D-alanine is described. The main steps of synthesizing the 3-aminopyrrolidine moiety have included a Brich reduction of a cyclic enaminoester and the reduction of a pyrrolidinone to the pyrrolidine.

Altinicline (SIB-1508Y) an anti-Parkinson's agent was prepared in five steps from natural nicotine via a regioselective substitution of the pyridine ring of (S)-nicotine. The synthesis involved retention of configuration on the pyrrolidine ring and constitutes the shortest and highest yielding synthesis of this drug.

Simple calixpyrrole macrocycles, which provide an easy-to-synthesize example of an anion-binding agent, are presented. The method, which involves the purification of the crude product by following the utilization of thin-layer chromatography and recrystallization, helps reinforce the utilization of such commonplace organic chemistry techniques with respect to a useful synthesis while remaining within the time constraints of a typical organic laboratory.

An efficient, practical, and high yielding synthesis of (R)-2-methylpyrrolidine is described. The sequence allows for the scalable preparation of the target compound in just four synthetic steps and proceeds in 83% overall yield and >99% optical purity from readily available starting materials.

A practical synthesis of a key pharmaceutical intermediate, 2-[(1H-pyrrolo[2,3-b]pyridine-4-yl)methylamino]-5fluoronicotinic acid is described. To introduce the aminomethyl moiety of 4-aminomethyl-7-azaindole through a palladium-catalyzed cyanation/reduction sequence, a regioselective chlorination of 7-azaindole through the N-oxide is developed.

The key compound responsible for the aroma of bread, 6-acetyl-1,2,3,4-tetrahydropyridine, was constructed in an efficient three-step procedure from 2-piperidone in an overall yield of 56%. This compound was liberated in the final step under basic condition and a related synthetic route produced 2-acetyl-1-pyrroline, the principal component of cooked rice, in 10% overall yield.

The addition of N-(diphenylmethylene)glycinate esters (Ph2C=NCH2CO2R) to [60]fullerene under Bingel conditions gives [60]fullerenyldihydropyrroles and not methano[60]-fullerenyl iminoesters [C60C(CO2R)(N=CPh2)] is reported. New mechanistic details are proposed to account for the formation of [60]fullerenyldihydropyrroles and their reductive ring-opening reactions.

Aldimines, generated in situ by the reaction of primary amines or anilines with aldehydes, undergo smooth reaction with various 1,1-cyclopropanediesters in the presence of catalytic Yb(OTf)3. The products are pyrrolidines in which the major diastereomer bears a cis relationship between substituents at the 2- and 5-positions.

A practical and cost-effective synthesis of 3,3-difluoropyrrolidine is reported. The synthesis involves the isolation of two intermediates, which are prepared by two efficient through processes, a Claisen rearrangement followed by a Ru(VIII)-catalyzed oxidation to prepare the 2,2-difluorosuccinic acid and an efficient cyclization to form N-benzyl-3,3-difluoropyrrolidinone followed by BH3.Me2S reduction.