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The HIV-1 integrase (IN) inhibition process that targets divalent metal ion cofactors is analyzed. It is shown that HIV-1 IN needs divalent metal cations to achieve phosphodiester bond cleavage of DNA.

An alternative methodology to [S.sub.N]Ar methodology is described for the synthesis of 4-aminoquinolines. Palladium catalysis is used as a key step for forming the desired C-N bond under conditions that are milder and more convenient than the existing [S.sub.N]Ar methodology.

A concise and general method is designed for the synthesis of 2-phenylquinoline-4-carboxamides functionalized at position 3 of the quinoline ring including the preparation of tin compound 3 and the application of the labeling with carbon-11 of SB 222200. The Stille coupling of 3-trimethylstannylquinoline 3 with methyl iodide labeled with carbon-11 has constituted an efficient route to [[super 11]C]-SB222200 [[super 11]C]-2.

A newly developed indole synthesis methodology for the preparation of a family of KDR kinase inhibitors that have potential use in cancer therapy is reported. This family of potent KDR kinase inhibitor contains an indol-2-yl quinolin-2-one structure and utilizes a Pd-catalyzed tandem C-N and C-C coupling sequence.

The excited state tautomerization dynamics of 7-hydroxyquninoline in the water pools of reverse micelles was investigated by monitoring time-resolved fluorescence spectra and kinetics. The normal and tautomeric species were found to reside preferentially in the bound and free-water regions of the micelles, respectively and the excited-state tautomerization of the normal species in the bound-water layers was suggested to occur via two different channels, depending on rotamers at the moment of excitation.

The tetra-(8-hydroxyquinolinato) boron complex (Bq) and 3,3',4,4'-benzophenone tetracarboxylic anion (BPTC) were intercalated into layered double hydroxides with an ion-exchange method. Elemental analyses, powder X-ray diffraction, FTIR spectra, and thermogravimetric analyses indicated that the hydrothermal treatment could improve the reaction process, purity and crystallinity of products.

Stereocontrolled intramolecular alpha-amidoalkylation reactions of (sub L)-DOPA-derived succinimides are studied. Addition of MeLi to nonracemic succinimides yields oxoamides, which are cyclized upon treatment with Lewis or protic acids to afford (5S,10bS)-trans 11 or (5S,10bR)-cis 12 pyrroloisoquinolines with variable diastereoselectivities, but with high enantiomerical purities.

The investigation is conducted on the crystal structures of a new series of alpha,beta-unsaturated ketoximes, 8-14, carrying the terminal 4-pyridinyl, 3-pyridinyl, or 4-quinolinyl subunit by X-ray structural analysis. The result reveals that alpha,beta-unsaturated ketoximes carrying a terminal pyridine or quinoline subunit are versatile building blocks for supramolecular syntheses.

The effects of nitrogen, oxygen, and moisture on the electron mobilities of tris(8-hydroxyquinoline) aluminum (Alq3) are investigated by time-of-flight (TOF) method at room temperature. The results indicate that water molecules induce electron traps even at very low dosages, and oxygen interacts with Alq3 at high dosages resulting in highly dispersive TOF signals.

A study on the ability of the 2-pyridyl and 1-isoquinolyl groups to direct metalation in the benzene series is reported. Comparisons revealed that the fluoro units was the stronger directing group for deprotonation than the 2-pyridyl.

A novel protocol for the one-pot construction of benzothieno[2,2-b]quinolines is devised, for whose b-fused quinoline structure, literature examples are almost totally absent. The protocol is based on a radical cascade reaction that entails a rare [3+2] annulation(super 17) and is initiated by a still uncommon addition of an aryl radical to an isothiocyanate.

The commercially available and air-stable catalyst [[RhCl[(CO).sub.2]].sub.2] is used to perform Rh(I)-catalyzed direct arylation of quinolines and 2-substituted pyridines couple with aryl bromides to obtain ortho-arylated azine products. The reaction could also be carried out by using aroyl chlorides as an effective azine coupling partners to give ortho-arylation products via a decarbonylation pathway.

Intramolecular cyclization of suitable functionalized piperidines via a reductive amination sequence is performed to construct quinolizidine ring systems. The preparation of the piperidine precursors based on a chain elongation of a piperidine aldehyde either by aldolization or by Wittig reaction is used to perform the total synthesis of quinolizidine (-)-217A from (S)-methyl 2-((S)-1-((R)-1-phenylethyl)piperidin-2-yl)propanoate. .

Platinum(II) chloride as a Lewis acid catalyst was employed to perform concise and efficient syntheses of indole carbamates, 1,2-dihydroisoquinoline carbamates, macrocyclic indole carbamates, indole ureas and indole phosphoranes. The reaction rate could be enhanced by performing the reaction under microwave irradiation.

The first total syntheses of the Lycopodium alkaloids (+)-nankakurine A, (+)-nankakurine B and the originally supported structure of nankakurine A is feature a demanding intramolecular azomethine imine cycloaddition as the key step is reported. The reaction generated the octahydro-3,5-ethanoquinoline moiety and installed the correct relative configuration at the spiropiperidine ring juncture.

A method is developed for the high yield and facile synthesis of isoquinolones from benzamides and alkynes through the oxidative ortho C-H activation of benzamides. The reactivity of the structurally related 1-hydroxyisoquinoline is shown, where both N- and O-containing rhodacyclic intermediates is generated, leading to the construction of different O- or N-containing heterocycles.

Pd-catalyzed decarboxylative cross-couplings of 2-(2-azaaryl)acetates with aryl halides and triflates are useful for the synthesis of some functionalized pyridines, quinolines, pyrazines, benzoxazoles and benzothiazoles. The studies have shown that the nitrogen atom at the 2-position of the heteroaromatics has coordinated to Pd(II) in the decarboxylation transition state.

The ability of ortho-alkynylanilines to react with aldehydes and amines in HFIP in the absence of any catalysts is demonstrated. The reaction yields trans-2,3-disubstituted 2,3-dihydro-4-iminoquinolines in a complete trans-selective manner via the three-component alkyne-imine metathesis.

A cooperative catalytic system consisting of CuI and pyrrolidine was developed for an efficient synthesis of 2-substituted quinolines. The synthesis performed via addition/cycloisomerization cascade revealed that the use of either catalyst alone does not give the product.

Gold-catalyzed intermolecular oxidations of internal alkynes are achieved with high regioselectivities by using 8-alkylquinoline N-oxides as oxidants and in the absence of acid additives. The reaction has allowed [alpha],[beta]-unsaturated carbonyls to be masked as propargyl moieties, which has provided a practical solution to compatibility issues with these functional groups encountered in syntheses of complex structures.

The asymmetric total synthesis of nonracemic korupensamine B is described. It has included a newly designed and highly trans-diastereoselective route to the tetrahydroisoquinoline ring and an unprecedented atropdiastereoselective Suzuki-Miyuara coupling for constructing fully fashioned naphthylisoquinoline framework that invokes [pi] stacking as a possible source of stereocontrol.

The application of quinolinium salt as an effective additive that acts as a conformation control element (CCE) to promote macrocyclization to form rigid cyclophanes via olefin metathesis or Glaser-Hay coupling is reported. The obtained cyclophanes does not cyclize in the absence of the additive and easy to synthesize additive is highly modifiable and have solubility profiles which allow for simple recovery via filtration.

The mechanisms involved in the enantioselective enantioselective intramolecular 1,5-hydride transfer/ring closure reaction are discussed. The application of the reaction for the preparation of ring-fused tetrahydroquinolines is also analyzed.

A new route is described for tetrahydroisoquinoline (THIQ) alkaloids involving the alkylation of [alpha]-aminonitrile as a key step, where the latter compound is prepared by anodic cyanation of the corresponding tertiary amine. The syntheses of ([plusmn])-carnegine, ([plusmn])-norlaudanosine and ([pulsmn])-O,O-dimethylcoclaurine are achieved.

Chelating fragment libraries of quinoline- and benzimidazole-sulfonamides are prepared and screened against different zinc(II)-dependent matrix metalloproteinases (MMPs). The fragments have shown inhibition of the metalloenzymes and preferences for different MMPs based on the nature of the chelating group and focused chelator libraries are a powerful strategy for discovering lead fragments for metalloprotein inhibition.

The various vapor phase properties of the 1-tert-butyl-6-cyano-1,2,3,4-tetrahydroquinoline (NTC6) and several other aminobenzonitriles are explained. A complete comparative analysis of the experimental vapor phase spectra, as well as the crystal structures is also presented.

The enantioselective construction of the hydroquinoline ring system from 1,5-polycarbonyl derivatives by using (R)-phenylglycinol as a chiral latent form of ammonia is described. Diastereodivergent routes are developed for enantiopure cis-2,5-disubstituted decahydroquinolines, which has included the alkaloid pumiliotoxin C.

A Pt[Cl.sub.4]-catalyzed hydroamination-triggered cyclization strategy is described for accessing biologically interesting N-containing heterocycles such as pyrrolo[1,2-a]quinoxalines, indolo[1,2-a]quinoxalines and indolo[3,2-c]quinolines. The reaction is appealing as it has involved multiple catalytic cycles catalyzed by a single metal catalyst Pt[Cl.sub.4] and an enhancement of the rate is observed when reactions are run under microwave-assisted conditions.

Trifluoroacetic anhydride-mediated tandem trifluoroacetylation/cyclization of cyanoacetanilides was carried out under mild conditions to give 4-hydroxy-3-trifluoroacetylquinolin-2(1H)-ones in good yields. Isolation and direct observation of the reaction intermediates showed that [alpha]-trifluoroacetylation resulted in the shortening of C[triple]N bonds with high electron density of CN groups.

Transformation of pyridine, quinoline, isoquinoline, azaindole, and pyrimidine N-oxides to their [alpha]-triazole and [alpha]-diazole derivatives is reported. The process involved reaction between the corresponding p-toluenesulfonylazoles and Hunig's base at high temperatures.

A useful enantioselective synthesis of angularly substituted 1-azabicyclic molecules that delivers the bicyclic amine products in good yield and 99% ee is reported. The developed enantioselective synthesis provides s a new strategy for dynamic kinetic resolution in which a rapid tautomeric equilibration of diastereomeric iminium cations is combined with a diastereoselective sigmatropic rearrangement.

Nitrile addition to cyclohexadienyium-Fe[(CO).sub.3] perchlorate salt has provided an efficient entry into the angularly substituted cis-fused perhydroisopuinoline ring system. The main steps in the assembly of the angularly substituted cis-octahydroisoquinoline ring have included the transformation of the nitrile to an N-(benzylmethylencie)amino group and a diastereoselective intramolecular Michael reaction to form the bicyclic ring.

A domino reaction was developed via palladium-catalyzed Sonogashira coupling of benzimidoyl chlorides with 1,6-enynes and then cyclization to produce quinoline derivatives. The reaction condition and scope of the process is simple, rapid, and general and could be carried out with readily available substrates.

A new and efficient method was developed for the synthesis of substituted quinolines via intramolecular electrophilic cyclization of 1-azido-2-(2-propynyl)benzene. The cyclization reaction was performed in the of electrophilic reagents ([I.sub.2], [Br.sub.2], ICl, NBS, NIS, and HNT[f.sub.2]) in [CH.sub.3]N[O.sub.2] at room temperature or in the presence of catalytic amounts of Au[Cl.sub.3]/AgNT[f.sub.2] in THF at 100 degree [Celsius] to afford the corresponding quinolines.

Zinc triflate catalyzed cyclization of ethenetricarboxylate derivatives with 2-aminobenzaldehydes are examined at different temperatures. The regioselectivity and yield of bridged tetrahydroquinoline derivatives and hydroxy tetrahydroquinolines from the thermal reaction are also discussed.

Intramolecular Diels-Alder cycloaddition of N-substituted oxazolone triene has allowed direct entry to the functionalized octahydroquinoline. The manipulation of the framework by stereo- and regioselective introduction of the 5-methyl substituent, followed by excision of the carbamate, has produced ([plusmn])-2-epi-pumiliotoxin C.

The efficient synthesis of 2-substituted tetrahydroquinolines is achieved by the domino reaction of N-indayl(methoxy)amines, which has elimination of an alcohol, the rearrangement of an aryl group and the addition of an organolithium or magnesium reagent. The synthetic utility of the method is shown by the stereoselective formal synthesis of ([plusmn])-martinellic acid.

The palladium(0)-catalyzed cross-coupling reaction of various 2-haloheteroaromatics with 2-stannylated pyridines and quinolines was used to prepare ABC analogues of the antitumor antibiotic lavendamycin, which contain the key metal chelation site and redox-active quinone unit essential for biological activity. The gold-catalyzed intramolecular cycloisomerization of N-(prop-2-ynyl)-1H-indole-2-carboxamide was used to efficiently obtain a [beta]-carbolinone derivative that was subsequently used for a Pd(0)-catalyzed cross-coupling directed toward the synthesis of lavendamycin analogues.

A thorough structural, experimental and computational analysis were performed on the derivatives of (3-sec-butyl-2,3-dihydroisoquinolin-4-ylidene)acetic acid to gain better understanding of the structure-activity relationships. The solid state structures revealed that the crystal packing as well as the intermolecular interactions depends on the substituent nature of the COOR group.

A convenient and highly regioselective synthesis of substituted isoquinoline derivatives from various aromatic ketoximes and alkynes via a one-pot, rhodium-catalyzed C-H bond activation is described. A probable mechanism that involves chelation-assisted C-H activation via oxidative addition of Rh(I) to an ortho-C-H bond, insertion of the alkyne, reductive elimination, intramolecular electrocyclization, and aromatization is also described.

The article discusses a new approach, wher in the gold(I)-catalyzed intramolecular hydroamination of alkynyl carbamates is employed for the direct synthesis of various isoquinolines. The methodology is shown to be also applicable to the synthesis of various heterocycles, including nitidine.

The application of the metal-free bronsted acid for the catalysis of the different addition reactions of numerous compounds is discussed. The process is shown to be extremely useful for the synthesis of the dihydro-2H-chromenones, and tetrahydroquinolinones under mild conditions.