INTRODUCTION:Acetylation is a widely occurring post-translational modification (PTM) of proteins that plays a crucial role in many cellular physiological and pathological processes. Over the last decade, acetylation analyses required the development of multiple methods to target individual acetylated proteins, as well as to cover a broader description of acetylated proteins that comprise the acetylome. Areas covered: This review discusses the different types of acetylation (N-ter/K-/O-acetylation) and then describes some major strategies that have been reported in the literature to detect, enrich, identify and quantify protein acetylation. The review highlights the advantages and limitations of these strategies, to guide researchers in designing their experimental investigations and analysis of protein acetylation. Finally, this review highlights the main applications of acetylomics (proteomics based on mass spectrometry) for understanding physiological and pathological conditions. Expert opinion: Recent advances in acetylomics have enhanced knowledge of the biological and pathological roles of protein acetylation and the acetylome. Besides, radiolabeling and western blotting remain also techniques-of-choice for targeted protein acetylation. Future challenges in acetylomics to analyze the N-ter and K-acetylome will most likely require enrichment/fractionation, MS instrumentation and bioinformatics. Challenges also remain to identify the potential biological roles of O-acetylation and cross-talk with other PTMs.

Photosensitive dye based boron dipyrromethene polymer has been investigated in the scope of photo-assisted rechargeable batteries. Under visible light, a 0.8 V gain has been observed for the BODIPY moiety reduction process. The light energy contributes advantageously to the charge yield of the organicmaterial potentially involved in lithium batteries.

[147-85-3] C5H9NO2 (MW 115.15) InChI = 1S/C5H9NO2/c7-5(8)4-2-1-3-6-4/h4,6H,1-3H2,(H,7,8)/t4-/m0/s1 InChIKey = ONIBWKKTOPOVIA-BYPYZUCNSA-N (chiral auxiliary1 in asymmetric synthesis) Physical Data: mp 228–233 °C (dec.); [α]D20 = −84° (c = 4, H2O); ninhydrin yellow in color. Solubility: sol H2O, alcohol; insol ether. Form Supplied in: white solid; widely available; inexpensive. Analysis of Reagent Purity: measurement of optical rotation; mp. Handling, Storage, and Precautions: cold and dry storage.

OBJECTIVESWe report the synthesis, antibacterial activity and toxicity of 24 bis-indolic derivatives obtained during the development of new ways of synthesis of marine bis-indole alkaloids from the spongotine, topsentin and hamacanthin classes.METHODSInnovative ways of synthesis and further structural optimizations led to bis-indoles presenting either the 1-(1H-indol-3'-yl)-1,2-diaminoethane unit or the 1-(1H-indol-3-yl)ethanamine unit. MIC determination was performed for reference and clinical strains of Staphylococcus aureus and CoNS species. MBC, time-kill kinetics, solubility, hydrophobicity index, plasma protein-binding and cytotoxicity assays were performed for lead compounds. Inhibition of the S. aureus NorA efflux pump was also tested for bis-indoles with no antistaphylococcal activity.RESULTSLead compounds were active against both S. aureus and CoNS species, with MICs between 1 and 4 mg/L. Importantly, the same MICs were found for MRSA and vancomycin-intermediate S. aureus strains. Early concentration-dependent bactericidal activity was observed for lead derivatives. Compounds with no intrinsic antibacterial activity could inhibit the S. aureus NorA efflux pump, which is involved in resistance to fluoroquinolones. At 0.5 mg/L, the most effective compound led to an 8-fold reduction of the ciprofloxacin MIC for the SA-1199B S. aureus strain, which overexpresses NorA. However, the bis-indole compounds displayed a high hydrophobicity index and high plasma protein binding, which significantly reduced antibacterial activity.CONCLUSIONSWe have synthesized and characterized novel bis-indole derivatives as promising candidates for the development of new antistaphylococcal treatments, with preserved activity against MDR S. aureus strains.

A practical sequence for the synthesis of optically active heteroaryl α-(hydroxyamino) esters was explored. The highly diastereoselective addition of heteroaromatics to a cyclic chiral nitrone allowed access to a series of heteroaryl hydroxylamines. The scope of this reaction was evaluated on substrates possessing a pyrrole, an indole, or a furan core. The three-step sequence afforded the α-(hydroxyamino) esters in good overall yields (36–62 %) with good enantiomeric excess values (76 to ≥98 %).

A new strategy for the preparation of unsymmetrical 2,2'-bis(pyrrolyl)alkanes has been developed. It involved the condensation of pyrrole derivatives onto N-benzylhydroxylamines in the presence of HCl. This two-step procedure provided access to a wide variety of 2,2'-dipyrromethanes (3a-m). It has also been extended to the synthesis of tripyrromethanes 4a-d and of N-confused dipyrromethanes 6a-d.

The stereoselective synthesis of penmacric acid, an optically active C-4 substituted pyroglutamic acid, has been efficiently achieved through an unusual 11-step sequence starting from simple N-triisopropylsilylpyrrole. The key-steps are the initial addition of the pyrrole nucleus onto a chiral nitrone and the obtention of the pyroglutamic acid moiety by reductive hydrogenation of the pyrrole followed by oxidation of the corresponding pyrrolidine into pyrrolidinone.

Regioselective additions of pyrroles to a variety of optically active nitrones under smooth acidic conditions lead to chiral pyrrolic N-hydroxylamines in good to excellent yields. Depending on the position of the chirality on the nitrone partner, the addition products have been isolated with high diastereoselectivity levels. Reaction of glyoxylate based chiral nitrones either at the C-2 or at the C-3 position of the pyrrole nucleus afforded N-hydroxyamino esters in high yields as single diastereoisomers. These adducts allow access to enantio-enriched non proteinogenic 2'- and 3'-pyrrolylglycines (13 and 19 respectively).

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

[4674-68-4] C2H4N2 (MW 56.07) InChI = 1S/C2H4N2/c1-4-2-3/h4H,1H3 InChIKey = MCLITRXWHZUNCQ-UHFFFAOYSA-N (reagent used for the synthesis of 2-N-methylaminooxazoles, hydantoins, and related heterocycles) Physical Data: mp between −50 and −40 °C; bp not described because of its spontaneous trimerization above its mp;1 density unknown. Possible use as a stabilizer for the storage of organic isocyanates. Solubility: soluble in H2O, alcohol, ether, and most organic solvents. Form Supplied in: colorless liquid; not commercially available. Preparative Methods: often prepared by the Von Braun synthesis involving addition of methylamine to cyanogen bromide in an ethereal solution.2 Other preparation methods involve the addition of methylamine to cyanogen chloride,3, 4 or to potassium cyanide in the presence of bromine,5 or to μ-disulfido dicarbonic acid dinitrile.6 Treatment of methyl thiourea by lead (IV) oxide 7 or by silver(I)oxide,8 or of cyanamide by dimethyl sulfate in a methanolic solution of sodium methoxide or in water have also been described.9, 10 The title compound is obtained either by decomposition of 1-methyl-5-tetrazolyllithium 11 or by chlorination of a suitable isothiourea.12 Purification: it is best achieved by removal of the solvent below 5 °C without light to limit the formation of trimethylisomelamine 1 Handling, Storaege, and Precautions since trimerization of liquid methyl cyanamide occurs readily above its melting point, it may be preserved as crystals by cooling with Dry Ice.1 Toxic.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

N-Benzylnitrones react with heteroaromatic compounds such as pyrroles or furan in the presence of hydrogen chloride. Either heteroaromatic N-benzylhydroxylamines, symmetrical or unsymmetrical 2,2′-bis(heteroaryl)alkanes could be selectively produced depending on the experimental conditions.

The first total synthesis of enantiopure (S)-(−)-cyclooroidin is described. Absolute configuration of this natural product has been confirmed by comparison of the optical rotation value of our synthetic sample with the one measured on natural cyclooroidin.

The first total synthesis of enantiopure (S)-(-)-cyclooroidin is described. Absolute configuration of this natural product has been confirmed by comparison of the optical rotation value of our synthetic sample with the one measured on natural cyclooroidin. (c) 2006 Elsevier Ltd. All rights reserved.

Absolute configuration of natural cyclooroidin was confirmed to be (S) by comparison of its optical rotation value with a synthetic sample of (S)-(−)-cyclooroidin.