Using new variations of anionic aromatic chemistry, the total synthesis of oxygenated brazanquinones (1a-1c), derived from beta-brasan, a natural product isolated from Caesalpina echinata, via carbamates 2a-2c is described.

A new strategy which uses very cheap FeCl3 as an effective catalyst in the presence of Me3SiCl has been developed for the conjugate addition of enones and chalcone with unactivated weakly nucleophilic carbamates.

Solvent-free reaction conditions facilitate a range of aromatic C-H functionalisations that traditionally require acidic or disfavoured solvents. These reactions include selective ortho- and meta-arylation of aryl carbamates and anilides and selective halogenation reactions.

An unexpected stereoselective anomeric substitution with carbamates promoted by HNTf2 is described here. Our experiments suggest that the observed diastereoselectivity is a result of thermodynamic equilibration of protonated N-acyl aminals.

A Cu-diamine complex effectively catalyses tandem C-N bond formation on 2-(2-haloalkenyl)-aryl halide substrates, to deliver a series of N-functionalised indoles. Anilines, amides and carbamates are all effective coupling partners under the developed conditions.

The geometry of the double bond in oxazolidinone-substituted ene carbamates controls the mode selectivity (ene reaction versus [2+2] cycloaddition) of singlet oxygen through stereoelectronic effects, whereas the chiral auxiliary provides high diastereoselectivity through steric shielding.

OBJECTIVES to evaluate and indicate the procedure to be followed in the health unit, both for diagnosis and the treatment of acute exogenous intoxications by carbamates or organophosphates. METHODS a descriptive study based on retrospective analysis of the clinical history of patients diagnosed with intoxication by carbamates or organophosphates admitted at the emergency unit of the Hospital ...

Measurements of the O(2) consumption and of the potential of frog skin, made under comparable conditions, show that the homologous carbamates (ethyl, propyl, butyl, and amyl) reduce both the O(2) consumption and the potential, but not in a similar manner. In this respect, the effect of the carbamates is like the effect of reduction in O(2) tension. The simple lysins (saponin and the bile salts)...