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Dinemasone C is prepared from cis-tetrahydro-4-hydroxy-6-methyl-2-pyrone by aldol reaction with 2,4-hexadienal, epoxidation followed by cyclization, and epimerization of the ring fusion. Dinemasone C, epi-dinemasone C, anhydrodinemasone BC and nor-dinemasone B are shown to be active against bacteria, which has included Legionella pneumophila Corby, algae and fungi.

The structure of the aggregates formed when mixing methyllithium and lithium chloride in THF is analyzed by multinuclear magnetic resonance at 170 K. The studies have shown that only the dimer [(MeLi)(LeCl)] is observed in equilibrium with [[MeLi].sub.4] and [[LiCl].sub.2].

Time-resolved spectroscopic experiments are used for examining the kinetics and mechanisms of the photodeprotection reactions for p-methoxyphenacyl (pMP) compounds, p-methoxyphenacyl diethyl phosphate (MPEP) and diphenyl phosphate (MPPP). The density functional theory (DFT) calculations have shown a substantial solvation effect that is connected with the methoxy versus hydroxyl substitution in accounting for the different deprotection reactivity of pMP and pHP compounds.

The article presents a new methodology, which can be used for the concise and efficient synthesis of the -trifluoromethylbenzo[b]furan compounds. The application of the extended Pummerer reactions for the direct ortho functionalization of different phenols for the synthesis process is also analyzed.

The studies have shown that in poly(ADP-ribose) glycohydrolase (PARG) null embryonic trophoblast stem (TS) cells that the absence of PAR hydrolysis led to PAR-modified histones H1, H2A and H2B. It is shown that greater DNA accessibility, increased DNA damage, and increased cell death have contributed to the PARG null cell phenotype in response to genotoxic stress.

An efficient strategy is described for preparing tartaric acid building blocks for totally regioselective trangformations or derivatizations. Type I and II building blocks with orthogonal sets of protecting groups are obtained starting from L-tartaric acid or L-dimethyl tartrate.

The conjugate addition of lithiated methyl pyridines to cyclic and acyclic enones is described. The addition of 2-picoline to 3-penten-2-one has led to a concise synthesis of the alkaloids ([plusmn])-senepodine G and ([plusmn])-cermizine C.

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.

The hetero-Diels-Alder (HDA) reaction of 1-(diethoxyphosphonyl)-1,3-butadiene, 1-(dibenzyloxyphosphonyl)-1,3-butadiene, and 1-(diethoxyphosphonyl)-3-tert-butyldimethylsilyloxy-1,3-butadiene with various heterodienophiles is examined as a new synthetic route for aminophosphonic derivatives. The resulting 6-phosphono-3,6-dihydro-1,2-oxazine cycloadducts have shown that a limited number of chemical steps are allowed to obtain a variety of aminophosphonic compounds of potential interest in medicinal chemistry.

Several theoretical, as well as experimental studies are conducted to explain the synthesis, as well as the photodynamics involved in the functioning of the 9-mesitylacridinium ion-modified gold nanoclusters.

The article presents a new methodology, which uses the [1.sup]H relaxation dispersion phenomenon for the quantification of the [13.sup]CH[D.sub.2] methyl group probes of millisecond time scale exchange in proteins. The application of the technique for the analysis of proteasome gating residue dynamics is also discussed.

The electron paramagnetic resonance spectrum of the spin-label 2,2,6,6,-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC)-the C-terminal tail of the transducin [alpha] subunit (Gt[alpha](340-350)) has disclosed greater immobilization of the nitroxide upon binding to rhodopsin upon photoactivation (R*) when compared to that of the N-terminally modified Proxyl-Gt[alpha](340-350) analogue. TOAC and Proxyl spin-labels in the GPCR-G-protein system have provided unique biophysical probes that are used for analyzing the structure and conformational changes at the rhodopsin-G-protein interface.

The reaction of the active Ni(I) state of methyl-coenzyme M reductase ([MCR.sub.red1]) with BES (2-bromoethanesulfonate) and coenzyme B (N-(mercaptoheptanoyl)threonine phosphate (CoBSH) or its analogue, Co[B.sub.6]SH (N-(6-mercaptohexanoyl)threonine phosphate), is analyzed by transient kinetic measurements. The results have supported the hybrid mechanism of methanogenesis by MCR that has included both alkyl-Ni and radical intermediates.

Site-specific [super 1]H chemical shift anisotropy (CSA) tensors are derived for the well-ordered backbone amide moieties in the B3 domain of protein G (GB3). DFT calculations on pairs of N-methyl acetamide and acetamide in H-bonded geometries taken from the GB3 X-ray structure has correlated with experimental data and has indicated that H-bonding effects have dominated variations in the [super 1][H.sup.N] CSA.

The preparation of 1,4,7-trimethyloxatriquinane, a 3-fold tertiary alkyl oxonium salt, is presented. [S.sub.N]2 is the only reasonable mechanistic interpretation for the reaction between 1,4,7-trimethyloxatriquinane and [N.sub.3.sup.-], despite the fact that substitution has occurred at a tertiary carbon center.

Cyclometalated platinum(II) complexes (C-P)Pt(Aryl)py has undergone oxidative addition reaction upon treatment with electrophilic fluorination reagents, Xe[F.sub.2] or N-fluoro-2,4,6-trimethylpyridinium tetrafluoroborate, in order to give products of C-C coupling. The N-F salt has favored the C-C coupling reaction while Xe[F.sub.2] has provided the unprecedented benzylic fluorination of one of the ortho-methyl groups of the mesityl ligand.