1H NMR and IR Spectroscopic Study of the Structure of the Major Component of the 99mTc HMPAO (Hexamethylpropyleneamino Oxime) Radiopharmaceutical Preparation

d,l-Hexamethylpropyleneamino oxime (HMPAO) was synthesized and isolated from a mixture of d,l - and meso-isomers. The structure of the conformers was studied using ¹H NMR spectroscopy over a broad range of pH. A method for estimating the amount of meso-form present in the mixture of isomers was proposed. It was shown that specific features of the IR spectra depend on the structure of the isomers and on the difference between the packing of molecules in the crystal lattice.     

The reactions of polyfluorocarbonyl compounds with phenylhydrazines

Methyl trifluoropyruvate (II) reacts with phenylhydrazine andp-nitrophenylhydrazine to give the corresponding phenylhydrazones (III) and (IV). The reaction of phenylhydrazine with hexafluoroacetone (I) at 20°C leads to the product of the C²-hydroxyalkylation of the aromatic ring (V). The hydroxyalkylation of hydrazobenzene under the same conditions is complicated by a benzidine rearrangement.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 948–950, April, 1990.     

Reactions of diarylamines with hexafluoroacetone

Diphenylamine reacts with hexafluoroacetone to give a mixture of products, of which 2-(1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl)diphenylamine (II) was isolated. N-Arylanthranilic acids modify the 1,1,1,3,3,3-hexafluoro-2-hydroxy-2-propyl group upon the reaction of its sodium salt with the hydrate of hexafluoroacetone (I) under mild conditions. This method gave 4-(1-hydroxy-1-trifluoromethyl-2,2,3-trifluoroethyl)-N-(2,3-xylyl)anthranilic acid from N-(2,3-xylyl)anthranilic acid in 93% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 952–954, April, 1991.     

Secondary metabolites of Pyricularia oryzae II. Polyketide metabolites

A number of exometabolites have been isolated from the deuteromycetePyricularia oryzae Cav., of which harman and O-demethyldiaporthin have been isolated from this species for the first time. The latter is the first example of a hexaketide from fungi of the genusPyricularia, for which only penta- and heptaketides have previously been described. All-Union Scientific-Research Institute of Phytopathology, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 471–475, July–August, 1991.     

Reactions of polyfluorocarbonyl compounds and their trifluoroacetylimines with fused heterocycles

C-Hydroxy- andC-aminoalkylation of iminodibenzyl, iminostilbene, phenoxazine, and phenothiazine with hexafluoroacetone, methyl trifluoropyruvate, and their trifluoroacetylimines were investigated. The substitution occurred at one or severalpara- andortho-positions to the N atom of the heterocycles. In the case of methyl trifluoropyruvate and its derivative the substitution in theortho-position was accompanied by the formation of lactams.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1239–1242, May, 1996.