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The reduction of polybrominated o- and p-nitrophenols with granular tin in concentrated aqueous HCl gave polybrominated aminophenols which were diazotized with sodium nitrite in concentrated sulfuric acid at 0°C to obtain polybrominated o- and p-quinone diazides. Their thermolysis with elimination of nitrogen generated ketocarbenes which reacted with acetylacetone to form insertion products at the activated methylene group. Ketocarbenes generated from o-quinone diazides reacted with typical dipolarophiles such as acetonitrile, benzonitrile, styrene, and phenylacetylene to afford the corresponding [3 + 2]-cycloaddition products. [ABSTRACT FROM AUTHOR]

The reaction of 2,3,5,6-tetrabromo-4-hydroxybenzoic acid with a 10-fold excess of NaNO in the glacial acetic acid at 20°C affords tetrabromonitrosophenols whose further transformations under the reaction conditions leads to the formation of a mixture of 2,4,5,6-tetrabromo- p-quinone diazide and tetrabromo- p- and - o-nitrophenols in the molar ratio 37: 2: 1. Under similar conditions the 3,4,5,6-tetrabromo-2-hydroxybenzoic acid is converted into a mixture of 3,4,5,6-tetrabromo- o-quinone diazide with the same nitrophenols in the ratio 13: 1: 3. The reaction of sodium 2,3,5,6-tetrabromo-4-hydroxy-benzoate with NaNO in dilute acetic acid resulted in a quantitative yield of tetrabromo- p-quinone monooxime. [ABSTRACT FROM AUTHOR]

The reaction of 3,5-dibromo-4-hydroxybenzoic acid, its sodium salt, and also sodium 3,5-dibromo-2-hydroxybenzoate with NaNO2 in a glacial acetic acid at room temperature led to the formation of a mixture of dibromonitrophenol resulting from nitrosodecarboxylation accompanied by a rearrangement processes and followed by oxidation of the arising nitrosophenols. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented related to successful coronary artery bypass surgery in a patient with a novel heterozygous FVII mutation performed without prophylactic replacement therapy.