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The observations of rotationally resolved OH- and CH-stretch vibrational transitions in CH2OH obtained in a molecular beam by using double resonance ionization detected IR (DRID-IR) spectroscopy are reported. Rotationally resolved IR spectra are obtained in the region of the fundamental CH symmetric stretch (v3), CH asymmetric stretch (v2), OH stretch(v1) and the OH stretch overtone (2v1).

An experiment is conducted to determine whether the fluorescence properties of antibodies expressed at various stages of the immune response yield evidence for a decrease in the conformational heterogeneity of the antibody binding site as the maturity of the antibody increases. For this purpose, fluorescence from both the native tryptophan (Trp) side groups, and the fluorescent hapten analogue 6-propionly-2-(dimethylamino)naphthalene (Prodan), is characterized as a function of binding.

Molecular dynamics simulations of an all-atom-methylacetamide (NMA) model and a refined SPC model are presented. It is found that the two-methyl groups in the NMA molecule have different capabilities in forming weak C-H. . . O contacts in the NMA-water system.

The CH stretching vibrational modes of methylene group at the interfaces is studied with sum frequency generation vibrational polarized spectroscopy (SFG-VPS). The polarization analysis of SFG spectra, resulted in few explicit polarization selection rules for the assignment of CH stretching modes of the methylene groups and also helps in understanding IR and Raman studies on methylene group in the bulk condensed phases.

Studies on the role of the 9-methyl group in the salamander rod and cone pigments are reported. Pigments are generated by combining proteins expressed in COS cells with 11-cis 9-demethyl retinal, where the 9-methyl group on the polyene chain is deleted.

A zero-quantum correlation experiment for recording (super 1)H-(super 13)C correlations of methyl groups in highly deuterated, a methyl protonated large protein is presented. These zero-quantum spectra benefit from the TROY- effects, in which both intra- and inter -methyl dipolar relaxation interactions are minimized.

The formal sigma-bond methesis between the B-CH3 bond in position 12 of the lithium monocarbadodecaborate derivative is reported. The Li -induced B-arylation reaction are presently under examination.

The first total synthesis of porritoxin is accomplished and it is confirmed that the revised structure is that of the natural product. A key reaction is the use of iron pentacarbonyl to formylate an aryllithium when DMF and methyl formate proved insufficiently reactive.

A useful route to C1-monoalkylated C70 derivatives is provided. The results suggest that the Zn/RX method does not involve alkylation of the same discrete anions that are formed by deprotonation of hydrogenated fullerenes.

The density functional theory (DFT) and molecular mechanics (MM) are combined to explain the relationship between the structure of a free coenzyme and that bound to methylmalonyl-CoA mutase(MCM). The essential components of the coenzyme B12, including corrin, adenosyl group, and histidine bound to a protein chain are described by DFT while the rest of the system was treated at a MM level.

A study of the target sequences of methyl-CpG-binding protein 2 (MeCp2) in human cells using a preparative chromatin immunoprecipitation protocol complemented by indirect immunofluorescence microscopy is presented. The results show that MeCp2 shows selective binding behavior with murine major satellite DNA, Alu sequences, MARs and CpG islands and the classical human satellite DNAs II and III and L1 elements are not preferred target sites for MeCP2.

The investigation by Sinn and Kaminskly in 1980, suggests that methylalumoxane (MAO) is a highly active cocatalyst in ethylene and propylene polymerization by group 4 metallocenes which has promoted the studies on the structural determination of alumoxanes to exemplify their role in the polymerization studies. A novel terminal hydroxide containing alumoxane was prepared with treatment of aluminium dihydride and tert-butyl alternatively with water.

Selectively excited benzene and toluene in the gas and solution phase are investigated with ultrafast transient absorption spectroscopy to study the impact of a solvent on the time scales of intramolecular vibrational energy redistribution (IVR). The findings indicate that an internal rotor accelerates IVR in the gas phase significantly whereas the effect appears to be largely concealed in solution.

Methyl 3-phenyl-2-dimethylsilylpropionate's anodic oxidation occurs at a potential almost 1V positive of that required to oxidize other alpha-silyl esters. An anodic strategy is implemented to prepare a carbocation alpha to a carbonyl group.

The vapor phase CH stretching overtone spectra of 3,5-difluorotoluene, 2,3,5,6-tetrafluorotoluene, and 2,3,4,5,6-pentafluorotoluene are measured and analyzed. The main factor that determines the structure in methyl CH stretching overtone spectra of these molecules is the nature of the groups adjacent to the methyl group.

The rate constant curves k(E) for the formation of C(sub 7)H(sub 7)(super +) ions by methyl loss from energy selected ethylbenzene and o-xylene ions were determined over a range from 10(super 3) s (super -1) to 5 x 10(super 6)s(super -1). The C(sub 7)H(sub 7)(super +1) ions formed at the threshold have the structure of benzylium ions for ethylbenzene and that of tropylium ions for the o-xylene.

The GST-catalyzed conversion of COMC derivatives to the corresponding GSH conjugates is a multistep process involving the formation of a highly reactive glutathionylated exocyclic enone. The antitumor activities of the COMC derivatives could be explained on the basis of the ability of the exocyclic enone and/or underivatized COMC to function as Michael acceptors, resulting in the alkylation of biomacromolecules critical to cell viability.

The report was prepared to investigate the photodissociation of methylglyoxal (CH(sub 3)COCHO,MGLY) in the 290-400 nm region at 10 nm intervals by using dyl laser photolysis in combination with cavity ring-down spectroscopy. Absorption cross section of methylglyoxal was obtained.

The study was conducted to investigate the basic structure and properties of MTBE(methyl tert-butyl ether) a widely used gasoline additive and various analogues as well as an analogous class of amines to understand the reaction of such species in the environment. The gas-phase structures and properties were calculated using a variety of ab initio methods.

An examination of the major products of the thermal decomposition of methyl formate in the gas phase is presented. Some of the products are CH3OH, CH2O and CO, which are discussed in detail.

The 1H-13C correlation maps of protonated methyl groups in highly deuterated proteins are studied. A comparison of HSQC and HMQC pulse schemes is described. It is concluded that the HMQC correlation maps are more sensitive than the HSQC and the sensitivity results from the cancellation of intra-methyl dipolar relaxation interactions.

The solvated electron yield, spectrum and reactivity toward certain solutes in the ionic liquid methyl- tributylammonium bis(trifluoromethylsulfonyl)imide (R4NNTf2) are reported. The results indicate that this ionic liquid will be a very useful medium for radiolytic studies of chemical reactivity, such as electron transfer reactions.

A different measure for the degree of side-chain order about the Calpha-Cbeta bond can be derived from (Super 3)J(sub C-Cgama) and (Super 3)J(sub N-Cgama) couplings and these couplings can be measured at high accuracy, in particular for Thr, Ile, and Van residues. Side-chain dynamics in proteins can be characterized by the NMR measurement of (Super 13)C and (Super 2)H relaxation rates.

The kinetic and thermodynamic preference for aliphatic C-H bond activation, the reaction of tetramethyl silane (TMS) with [(NN)PtMe(TFE)][X] was studied. Although the reaction at C-H bond of TMS apparently occurs, the initial C-H activation product proved to be unstable and catalytic conversion of TMS and TFE solvent to methane and Me3SiOCH2CF3 was observed.

The spin-coupled (SC) model for the electronic mechanism of the gas-phase 13DC reaction of methyl azide and ethene is presented. It shows that not all 13DC reactions go through heterolytic bond rearrangements involving movement of well-identifiable orbital pairs that are retained along the entire reaction paths for reactants to product, such as the ones depicted in reaction mechanisms A1 and B.

Pyrolysis reactions of cubane and methylcubane were studied in a micro-flow tube reactor from room temperature to 100 K. Ab initio calculations performed to help interpretation and their possible mechanisms are discussed.

Methyl Red H* aggregate of predetermined size is successfully synthesized from the DNA conjugate involving multiple Methyl Red moieties in sequence. The Methyl Red H* aggregate in the single strand is converted into another aggregated structure by hybridization with the complementary strand, and its aggregated structure is controllable by the kinds of DNAs used for hybridization.

The electronic absorption spectra and the relaxation kinetics of the photoexcited methyl viologen(super .+) radical cation on the fs to ps time scale are reported. The results show that the excited viologen radical gives readily detectable transients on the time scale of 1-30 ps, which could be used to identify excited viologen products.

Cycloaddition of dichloroketene with dimethylcyclohexenes has been used as the key reaction in a new approach to bakkanes. Natural product synthesis has proven an excellent vehicle for the development of new synthetic methodologies.

Barriers and enthalpies for methyl radical addition to both the C- and S-centers of CH2=S, CH3CH=S and (CH3(sub2)C=S and for the methyl-transfer reactions that interconvert the S-centered and C-centered radical products were calculated. It was found that the methyl-transfer reactions that interconverted the two radicals did not provide a low energy pathway for obtaining the more stable radical.

The reaction of methyl iodide with Al(111) surface is studied by scanning tunneling microscopy (STM) and by first principles calculations. It is found that at 300 K methyl iodide decomposes on the Al(111) surface, forming methyl (CH3), methyldyne (CH) and adsorbed iodine.

The methyl cation and CF3(super +) attack saturated, acylic ketones to make vibrationally excited adduct ions. The resulting deep-seated rearrangements compete favorably not only with halonium metathesis but also with prompt fragmentations that require only hydride shifts.

Optical absorption and optoacoustic spectroscopy is used to measure the high overtone C-H stretching vibrations of anisole and thioanisole in liquid phases. A comparison of the DFT data with the overtone spectra confirmed the occurrence of the methyl C-H symmetric stretching at low wave number in anisole.

The ab initio study supports the idea of a trapping stabilization mechanism for radical species, that is the stabilization energy increases with system size. The magnitude of this energy is directly related to the degree of spin polarization induced on the closed shell molecular partner in the complex, a result that is in agreement with McConnell's criterion.

A series of di(naphthyl)carbenes (DNCs) have methyl groups on aromatic rings are generated by photolysis of the corresponding diazo precursors and studied not only by products analysis, but also by spectroscopic means. 'Parent' triplet alpha-DNC was shown to have a half-life of 70 ms, which is some 30 times larger than that of triplet diphenylcarbene whereas parent triplet beta-DNC was 2 orders of magnitude shorter lived than the alpha-isomer.

The formation of muoniated methyl radical due to the reaction of muonium with ketene is demonstrated. The isotope effect on the hyperfine constants of the muon and proton in their chemically similar locations is attributed to their diverse zero-point energies of the C - Mu and the C - H bonds.

A theoretical study conducted on the methyl and ethyl derivatives of C, Si, Ge, Sn, and Pb is presented. A comprehensive study of fully optimized geometries and reaction energies are presented for both methyl and ethyl families.

The serious disagreement between observed and calculated levels of CH3 has led to suggestions that the atmospheric models greatly underestimated the loss of CH3 due to poor knowledge of the rate of the reaction CH3+CH+M-->C2H6+M at low temperatures. The absolute rate constant for the self-reaction of CH3 is measured by using the discharge-flow kinetic technique coupled to mass spectrometric detection at T=202 and 298 K.

The preliminary results on the spin catalytic effects by paramagnetic and diamagnetic catalysts are presented. The potential spin catalyst power displayed by the stable free radical 2,2,6,6-tetramethylpiperidinoxyl (TEMPO) is discussed.

The study presents an approach to the discovery of allele-specific inhibitors of protein arginine methyltransferases. Protein arginine methyltransferases catalyzes the transfer of methyl groups from S-adenosylmethionine to arginine side chains in target proteins.

The cybotactic region surrounding three solutes dissolved within a [bmim](super +)[PF(sub 6) are measured. At 293 K the local dielectric constant and refractive index are 11.4 (plus or minus) 1.0 and 1.523 (plus or minus) 0.025, respectively.

A series of organosilicates are prepared using 1,2-bis(trimethoxysilyl)ethane (BTME) as silica precursor and alkytrimethylammonium chloride (CnTMACl) surfactants with different chain lengths as supramolecular templating materials. (super 13)C and (super 29)Si NMR data showed that after surfactant extraction, all samples consisted of pure organosilicate.

A dielectric study performed by means of the thermally stimulated depolarization thermally stimulated depolarization currents technique (super 15) in a range of poly (methyl methacrylate) (PMMA) based materials, bulk amorphous PMMA, diphastic PMMA+SiO2 composites and the same matrixes with dispersed laser-active dyes. The dielectric strength of the signals at the high temperature part of the spectrum is highly dependent on the water content of the sample and accordingly the conductivity level of the polymeric phase.

The conformational properties and geometric structures of trifluoromethyl fluoroformate, CF3OC(O)F (1), and perfluorodimethyl carbonate, (CF3O)(sub 2) (2), are studied by matrix IR spectroscopy, gas electron diffraction (GED) and quantum chemical calculations. It was seen that the quantum chemical calculations reproduce the structural and conformational properties of both compounds satisfactorily.

Two-(p-N-Alkyl-N-methylamino) benzylidene-1,3-indandione (1a) as model compound for the preparation of nonlinear optically (NLO) active Lanfmuir-Blodgett(LB) layers is studied. The study observed that the two main spectral bands in the LB films, and which can be deconvoluted form the solution spectra can be assigned to two nearly intrinsic molecular transitions, or to transitions associated with different conformers f the molecules.

A study of internal rotation in the ionic ground states of 1-, 2- and 3- (trifluromethyl)aniline (ABTF), by high resolution photoelectron spectroscopy (ZEKE-PFI) using the S1 state as the resonant intermediate is presented. It is shown that in all cases barriers were found that mirror the trends observed when the CF3 group is replaced by CH3, however, greater interaction with the NH2 group was apparent with CF3, but not the 3-isomer.

A study of electron attachment properties of a series of saturated disulfides: dimethyl disulfide, diethyl disulfide and dipropyl disulfide, by Rydberg electron-transfer spectroscopy (RETS), negative ion photoelectron spectroscopy (NIPES) and quantum chemistry calculation is presented. Both RETS and NIPES show that the valence anions of these disulfides are stable.

The reactions of phenyl cations were carried out with methanol and methyl fluoride. It resulted in the formation of benzenium ions under specified conditions.

The structure of the CH2OH radical was optimized at the UHF, UB3LYP, and MP2 levels. The isotropic hyperfine parameter calculations indicated that very good excitation energies could be obtained with a relatively small effort in comparison with the multireference single and double configuration interaction method.

Research is done on the decomposition of 4-methylpyrimidine, which was examined behind reflected shock waves in a pressurized driver single-pulse shock tube over the temperature range 1160--1330 K at overall densities of ~3 x 10(super -5) mol/cm(super 3). In conclusion, a reaction scheme containing 33 species and 91 elementary reactions was constructed to account for the observed product distribution and an examination on the decomposition mechanism is presented.