Structure-activity studies of oxazolidinone analogs as RNA-binding agents.

Many analogues of the antitumor agent irofulven have been readily prepared by replacing the allylic hydroxyl with a variety of nucleophiles. Analogues of acylfulvene (the precursor to irofulven) were also prepared by Michael reaction with acrolein. The toxicity of the analogues was determined, as well as preclinical antitumor activity. Several analogues exhibited good activity in mouse xenografts. Structural requirements for activity are discussed.

Structure-Activity Studies of Antitumor Agent Irofulven (Hydroxymethylacylfulvene) and Analogues

Stereoregular, cis–transoidal poly(phenylacetylene)s bearing strongly acidic functional groups as pendants, such as a phosphonic acid and its monoethyl ester and a sulfonic acid, were found to interact with various biomolecules such as peptides, proteins, amino sugars, and carbohydrates in water, and the complexes exhibited characteristic induced circular dichroisms in the ultraviolet–visible region of the polymer backbones, which resulted from the formation of predominantly one-handed helical conformations. On the other hand, the sodium salt of poly[(4-carboxyphenyl)acetylene], bearing a weak acidic carboxy group, showed induced circular dichroisms only in the presence of carbohydrates and some positively charged proteins. The sensitivity of the polymers to the chirality of various biomolecules was also investigated with circular dichroism spectroscopy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5039–5048, 2006

Chirality sensing of various biomolecules with helical poly(phenylacetylene)s bearing acidic functional groups in water

The N-(1-deoxy-D-fructos-1-yl) derivatives (Amadori compounds) of the endogenous opioid pentapeptide, leucine–enkephalin (11), leucine–enkephalin methyl ester (12) and of structurally related peptides (9,10) are synthesized. The equilibrium compositions of the prepared Amadori compounds 9–12 in D2O and [2H6]DMSO are determined using 13C NMR spectroscopy. In water, the β-pyranose, α-furanose and β-furanose forms are detected, the β-pyranose tautomer being the most abundant at equilibrium (67–75%). The α-pyranose form and open-chain keto form are not detected. In dimethyl sulfoxide, the equilibrium compositions of 9–12 are markedly shifted towards a higher proportion of furanose forms, amounting to two-thirds of the mixture. In addition to the α- and β-furanoses and β-pyranose tautomers, DMSO solutions of compounds 9–12 contain at equilibrium a relatively high proportion of the acyclic hydrate (gem-diol) form (ca. 10%).

Synthesis and13C NMR investigation of novel Amadori compounds (1-amino-1-deoxy-D-fructose derivatives) related to the opioid peptide, leucine–enkephalin

Multicomponent supramolecular materials, which comprise plural supramolecular architectures that exhibit distinct self-sorting behaviors, are receiving increasing attention because they can be impl...

One-Pot Construction of Multicomponent Supramolecular Materials Comprising Self-Sorted Supramolecular Architectures of DNA and Semi-Artificial Glycopeptides

The major tautomers of D-fructose in water are the β-pyranose and β-furanose forms, the former predominating. NMR studies have shown that when aqueous DNA is added, there is a shift in the β-pyranose ⇌β-furanose equilibrium, the latter form being favoured. It is suggested that this is caused by weak, preferential binding of the β-furanose form to DNA. This is supported by computer modelling, which shows that for the former, only two hydrogen bonds can be formed between sugar O–H groups and phosphate units, whereas three good bonds can be formed with the latter.Studies of the O–1H resonances of the anomeric groups of the two forms confirm this change in equilibrium. In addition this feature for the β-furanose form shifts to low-field without significant broadening. This indicates that strong hydrogen bonding to DNA occurs, but that the equilibrium is very rapid giving fast averaging of the NMR signals.

Binding of sugars to DNA. An NMR study of D-fructose

Binding of Sugars to DNA. An NMR Study of D-Fructose

Metal-Nitroxyl Interactions. Part 52. EPR Spectra of Nitroxyl Radicals (I)-(III) Coordinated to Manganese(III) Tetraphenylporphyrin via the Nitroxyl Oxygen.

Graham Eaton

Papers

Binding of sugars to DNA. An NMR study of D-fructose

Binding of Sugars to DNA. An NMR Study of D-Fructose

Metal-Nitroxyl Interactions. Part 52. EPR Spectra of Nitroxyl Radicals (I)-(III) Coordinated to Manganese(III) Tetraphenylporphyrin via the Nitroxyl Oxygen.