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Small molecules are frequently used as dyes, labels and markers to visualize and probe biophysical processes within cells. However, very little is generally known about the light-driven excited-state reactivity of such systems when placed in cells. Here an experimental approach to study ps time-resolved excited state dynamics of a benchmark molecular marker, astaxanthin, in live human cells is introduced.

Herein, we have developed a solvent-tailored ordered self-assembly strategy to create anisotropic nanomaterials. A trace amount of water has been found to be a predominant factor to direct peptide self-assembly into an anisotropic meso-matrix in DMSO. The obtained meso-matrix was applied to measure the anisotropic RDC parameter of organic molecules for structural elucidation.

Quinazoline skeletons are synthesized by amino acid catabolism/reconstruction combined with the insertion/cyclization of dimethyl sulfoxide for the first time. The amino acid acts as a carbon and nitrogen source through HI-mediated catabolism and is then reconstructed using aromatic amines and dimethyl sulfoxide (DMSO) as a one-carbon synthon. This protocol is of great significance for the further study of the conversion of amino acids.

NAMI-A is highly reactive to Sp1, a tumor metastasis related protein, resulting in the perturbation of the protein structure and disruption of the DNA recognition of Sp1. Interestingly, Sp1 is more susceptible than other zinc finger proteins to NAMI-A, suggesting that Sp1 could be the anti-metastasis target of NAMI-A.

Directed sortase A evolution yielded the variants R159G and D165Q/D186G/K196V with increased resistance (2.2-fold) and catalytic efficiency (6.3-fold) in 45% (v/v) dimethylsulfoxide. Interestingly, D165Q/D186G/K196V also showed an up to 4.7-fold increased activity for the conjugation of hydrophobic peptides/amines in co-solvents. MD simulations revealed that conformational mobilities are important for the gained resistance.

IT127 is a dinuclear transition metal complex that contains a Pt(ii) and a Ru(iii) metal center. We have shown that IT127 is significantly more effective in binding the 29-base sarcin ricin loop (SRL) RNA in comparison to Cisplatin, a hallmark anticancer agent. Binding site analysis shows that IT127 prefers purine bases and the GAGA tetraloop region of SRL RNA. Our results with a dihydrofolate reductase (DHFR) model system reveal that IT127 binding to mRNA reduces translation of DHFR enzyme and that the Ru(iii) and Pt(ii) centers in IT127 appear to work in a synergistic manner.

A coumarin based Schiff base was found to be an excellent indicator of moisture, via rapid in situ hydrolysis. A structure-relationship examination of a small library of Schiff bases revealed the critical importance of hydrogen bond acceptors in close proximity to the imine bond, and this observation was further supported by theoretical calculations as well as the solid state structure analysis. The most sensitive compound demonstrated a limit of detection and quantification of 0.18% and 0.54% v/v water in DMSO, respectively.

A novel chalcogen-mediated oxyfunctionalization mode of ynamides for the synthesis of α-chalcogenyl acrylamides has been developed. Independent of metal catalysts, external oxidants and additives, this mild process afforded a range of structurally diverse α-chalcogenyl acrylamides, including α-selanyl acrylamides and α-tellanyl acrylamides. Interestingly, diverse ynamides tolerated in this approach gave different stereoselectivities.

An oxothiosquaramide was shown to bind to chloride through hydrogen bonding interactions in DMSO and found to exhibit pH switchable choride transport across phospholipid bilayers via an antiport transport mechanism.

Using the widely available DMSO as the formylation reagent under oxidative conditions, an efficient Cu-catalyzed C3-formylation reaction of imidazo[1,2-a]pyridine C-H bonds to directly generate structurally sophisticated 3-formyl imidazo[1,2-a]pyridine derivatives has been developed. The reaction proceeded to generate products in good yields, and used the environmentally friendly molecular oxygen as the oxidant.

A novel ammonium iodide-induced sulfonylation of alkenes with DMSO and water toward the synthesis of vinyl methyl sulfones is described. The process proceeded smoothly under metal-free conditions with high stereoselectivity and good functional group tolerance. The reaction mechanism was revealed to proceed through a domino reaction of oxidation and elimination after the radical addition to alkenes.

The fluorescence intensity of N,N-dimethyl-4-((2-methylquinolin-6-yl)ethynyl)aniline exhibits an unusual intensification with increasing temperature, by activating more vibrational bands and leading to stronger TICT emissions upon heating in dimethyl sulfoxide. Based on the different temperature dependence at various wavelengths, as shown in the TICT fluorescence spectrum, this dye can be employed to ratiometrically detect temperature.

A facile and efficient one-pot synthesis of polysubstituted pyridin-2(1H)-ones from readily available enaminones and the cyanomethyl sulfonium bromide salt in the presence of cesium carbonate is developed, and a mechanism involving sequential nucleophilic vinylic substitution (S(N)V), intramolecular nucleophilic cyclization and dealkylation reactions is proposed.

Reaction of BiPh3 or Bi(O(t)Bu)3 with benzohydroxamic acid (H2-BHA) results in formation of novel mono- and di-anionic hydroxamato complexes; [Bi2(BHA)3]∞ 1, [Bi(H-BHA)3] 2, [Bi(BHA)(H-BHA)] 3, all of which display nM activity against Helicobacter pylori. Subsequent dissolution of [Bi2(BHA)3]∞ in DMSO/toluene results in hydrolysis to the first structurally authenticated {Bi34} oxido-cluster [Bi34O22(BHA)22(H-BHA)14(DMSO)6] 4.

Scalar coupling constants and signal splitting patterns in NMR spectra contain a wealth of short-range structural information. The extraction of these parameters from (1)H NMR spectra is often prohibited by simultaneous scalar coupling interactions with several other protons. Here we present a high-resolution NMR experiment where scalar coupling to only one selected signal is visible. All other couplings are removed from the spectrum. This real-time selectively refocused NMR experiment is achieved by spatially selective homonuclear broadband decoupling combined with selective refocusing during acquisition. It allows the unperturbed extraction of scalar coupling constants from the highly resolved acquisition dimension of NMR spectra.

A novel catalytic system TMSOTf/I2/DMSO for the oxidative coupling of terminal alkynes with virtually any primary/secondary amine leading to α-ketoamides has been developed. The reaction possibly proceeds via iminium ion formation, wherein DMSO acts as a solvent as well as an oxidizing agent.

Supported palladium nanomaterials catalyzed an intramolecular C-H amination reaction to produce carbazoles in moderate to excellent isolated yields, up to 92%.

A new binding strategy of linking quantum dots (QDs) to magnetic nanoparticles (MNPs) using DNA interaction with metal coordination bonding was developed. Platinum was selected for binding QDs to DNA. This novel self-assembled nanoconjugate would be a new probe for diagnosing a specific disease more accurately with its double modalities, fluorescence and magnetic property.

AH197, a trinuclear Ru(III)/Pt(II) metal complex, is strikingly more effective than the hallmark anticancer drug cisplatin and the Ru(III) clinical candidate NAMI-A in its binding to RNA and inhibition of primer DNA synthesis. Heteromultinuclear complexes could potentially serve as far better chemotherapeutics than mononuclear complexes.

Infinite square-tubular helices, [CuCl2(L)(S)] (L = bis(4-pyridyl)methylvinylsilane; S = Me2SO, HCONMe2), were constructed. This helical system affords three kinds of P, M crystals in Me2SO, and racemic crystals in HCONMe2. The cyclic voltammogram (CV) technique using the M-crystals is an effective tool for discerning the chirality of proline.

We present three crystal structures of diatrizoic acid (DTA) DMSO solvates illustrating progressive desolvation of the DTA molecule and concomitant increasing degree of DTA self-association. Using these structures, plausible pathways for overcoming the solvation shell of DTA during its crystallisation from solution are discussed.

With atmospheric oxygen as the oxidant, a novel copper(I)-catalyzed synthesis of aryl methyl sulfones from aryl halides and widely available DMSO is described. The procedure tolerates aryl halides with various functional groups (such as methoxy, acetyl, chloro, fluoro and nitro groups), which could afford aryl methyl sulfones in moderate to high yields. The copper-catalyzed aerobic oxidation and the cleavage/formation of C-S bond are the key steps for this transformation.

A newly designed terephthalic acid substituted amphiphilic L-glutamide was found to form organogels in DMSO and a broad range of metal ions, from simple Na(+), Li(+) to Cu(2+), Ni(2+), Eu(3+) and Tb(3+), could turn the self-assembled nanostructure into a uniform helical twist.

Purely hydrogen-bonded dimeric capsule formation through self-sorting of three different tripodal receptors, having similar size and bearing the same functionality, through dynamic self-assembly in polar solvents is reported.

A highly efficient method for the synthesis of oxazole derivatives from methyl ketones, benzoins and ammonium acetate has been established via a novel strategy-convergent integration of two self-labor domino sequences. Owing to the simple and readily available starting materials, mild reaction conditions, facile operation, and the high bioactivity of oxazole derivatives, this reaction promises diverse applications in medical chemistry. Additionally, this reaction could provide an efficient example for self-labor synthesis strategy of organic compounds., (This journal is © The Royal Society of Chemistry 2012)

The self-assembly of core-substituted naphthalene diimides bearing triethylene glycol motifs leads to the formation of stable vesicles in DMSO and CHCl(3)/MeOH (6 : 4, v/v) solvents. The vesicles were evaluated by means of UV/vis and fluorescence spectroscopy, transmission electron microscopy, atomic force microscopy and dynamic light scattering.

A simple, rapid and highly selective method has been developed for the direct visual detection of tryptophan in a mixture of amino acids or in a protein based on DMSO acceleration.

A palladium-catalyzed cyanation of the 3-position of indole sp(2) C-H bonds by the combination of NH(4)HCO(3) and DMSO as the "CN" source was achieved to provide aromatic nitriles in moderate to good yields with excellent regioselectivity. It represents a practical and safe cyanation method., (This journal is © The Royal Society of Chemistry 2011)

A combination of dimethyl sulfoxide (DMSO) and trifluoroacetic anhydride (TFAA) mediates functionalization at the 2α-position of indole derivatives. Carbon and heteroatom nucleophiles were directly introduced via a one-pot procedure in excellent yields., (This journal is © The Royal Society of Chemistry 2011)

The reaction of the basic bismuth nitrate [Bi(6)O(4)(OH)(4)](NO(3))(6)·H(2)O with sodium methacrylate in DMSO gave [Bi(38)O(45)(OMc)(24)(DMSO)(9)]·2DMSO·7H(2)O (OMc = O(2)CC(3)H(5)), which is highly soluble in organic solvents. By copolymerization of the bismuth oxido cluster with methyl methacrylate transparent, radiopaque organic-inorganic hybrid materials were obtained., (This journal is © The Royal Society of Chemistry 2011)

Three isomeric pyridine-containing L-glutamic lipids formed organogels in DMSO and self-assembled into different nanostructures of nanofiber, nanotwist and nanotube depending on the substituent position in the pyridine ring., (© The Royal Society of Chemistry 2011)

A copper-mediated methylthiolation of aryl halides with the widely available DMSO is described. The procedure tolerates a series of functional groups such as methoxy, nitro, chloro, fluoro, trifluoromethyl, formyl and methoxycarbonyl groups. Thus, it represents a simple and facile methylthiolation procedure., (© The Royal Society of Chemistry 2011)

Perdeuterated poly(acrylonitrile) is introduced as a practically proton-free alignment medium for the measurement of anisotropic NMR parameters; its use in conventional glass tubes and in a Kalrez® 8002 UP-based stretching device with resulting spectra of astonishing quality are demonstrated.

Significantly enhanced resolution in the -OH NMR spectral region was observed which, in combination with 2D (1)H-(13)C HMBC techniques, will open new avenues in structure analysis of natural products with phenol type -OH groups in complex natural extracts without the need of laborious isolation of the individual compounds.

A family of free-standing noble metal (Pd, Pt, Au, Ag) sub-micron tubes composed of nanoparticles (STNs) can be synthesized by a one-step electrochemical route in anhydrous dimethyl sulfoxide (DMSO) solution without addition of any other surfactants.

The tetrahedral bis(adeninyl)-Cu(I) complex, , self-associates in polar solvent through complementary hydrogen-bonding interactions and appears to mimic the natural assembly of duplex DNA.

The use of a pyrrole-strapped calix[4]pyrrole () permits the determination of chloride anion concentrations in mixed aqueous DMSO-d(6)-H(2)O environments via proton NMR spectroscopy.

Partially 2,3-O-methylated amyloses efficiently form inclusion complexes with polytetrahydrofuran and poly(epsilon-caprolactone) by simply mixing them in DMSO-H(2)O (1 : 9) solution, in contrast to the case of the parent amylose in which the corresponding inclusion complexes are only slightly formed.

An extended dipyridyl ligand (L1) capable of hydrogen bonding with guest species via urea functionalities has been designed and synthesised. Assembly of a silver(I) coordination polymer of L1 is dependent on the nature of the hydrogen bond acceptor in a logical extension of the monopyridyl analogue.

A canonical planar beta-hairpin peptide, stereochemically reengineered into a semicircular bracelet type motif by L-to-D stereochemical inversion in two pairs of its cross-strand neighbor residues, displays protein like ordering including two-state behavior in H2O, which is unusual for a small peptide of this size.

We have developed a methodology for the analysis of liposomal membranes and their contents using near-IR Raman spectroscopy on liposomes held in an optical trap. We were able to detect a variety of membrane components including lipids, cholesterol, and small molecule solutes such as ethanol, DMSO and hexafluoroisopropanol. The methodology is able to distinguish between solutes that equilibrate across the liposomal membrane from those that partition selectively into the lipid bilayer.