In a gasoline-contaminated site in Düsseldorf, Germany a two-year monitoring program was carried out to determine the presence, behavior, and fate of 12 gasoline additives in a total of 96 samples from 14 groundwater wells. The origin of contamination was suspected to be a gasoline spill at a gas station. Target compounds were methyl-tert-butyl ether (MTBE), its main degradation products, tert-...

The photodissociation dynamics of the tert-butyl radical (t-C(4)H(9)) were investigated using photofragment translational spectroscopy. The tert-butyl radical was produced from flash pyrolysis of azo-tert-butane and dissociated at 248 nm. Two distinct channels of approximately equal importance were identified: dissociation to H + 2-methylpropene, and CH(3) + dimethylcarbene. Neither the transla...

Cu(II) complexes of N2O2 type ligands, L(1)H2 and L(2)H2 [L(1)H2 = 6,6'-(((pyridin-2-ylmethyl)azanediyl)bis(methylene))bis(2,4-di-tert-butylphenol); L(2)H2 = 2,4-di-tert-butyl-6-(((3-(tert-butyl)-2-hydroxy-5-methylbenzyl)(pyridin-2-yl-methyl)amino)methyl)phenol], have been synthesized. Addition of nitrogen dioxide (NO2) in THF solutions of the complexes resulted in the nitration at the 4-positi...

The motional restrictions of the proline pyrrolidine ring allow this secondary amine amino acid to act as a turn inducer in many peptides and proteins. The pyrrolidine ring is known to exhibit two predominant pucker modes (i.e., C-4 (Cgamma) exo and endo envelope conformers whose ratio can be controlled by proper substituents in the ring). In nature, the exo puckered 4(R)-hydroxy-l-proline play...

A four-electron-reduced ruthenium(ii) NADH-type complex, [Ru(bbnpH4)(CO)2Cl](PF6) (bbnpH4 = 2,2'-(4-(tert-butyl)pyridine-2,6-diyl)bis(5,10-dihydrobenzo[b][1,5]naphthyridine)), has been successfully synthesized by mixing an NAD+-type ligand, bbnp (bbnp = 2,2'-(4-(tert-butyl)pyridine-2,6-diyl)bis(benzo[b][1,5]naphthyridine)), and [Ru(CO)2Cl2] under moderate water-gas-shift reaction conditions, wh...

OBJECTIVES To evaluate the stability of 12 triazolyl oxazolidinone (TOZ) derivatives in simulated gastric and intestinal fluids as well as in human plasma at 37 ± 1°C. MATERIALS AND METHODS A stability-indicating high-performance liquid chromatography (HPLC) procedure with a C(8) column (250 × 40 mm, 5 μm particle size) and a mobile phase of acetonitrile/H(2)O (50/50 v/v) at 1.0 ml/min was us...

The asymmetric synthesis of the orthogonally funtionalised compounds tert-butyl 2-N-benzyl-N-alpha-methylbenzylamino-5-methoxycarbonylmethylcyclopentane- 1-carboxylate and methyl 2-N-benzyl-N-alpha-methylbenzylamino-5-carboxymethylcyclo- pentane-1-carboxylate by a domino reaction of tert-butyl methyl (E,E)-octa-2,6- diendioate with lithium N-alpha-methylbenzyl-N-benzylamide initiated by a Micha...

In the crystal structure of the title compound, [Cd(NCS)2(C9H13N)2] n , the Cd(II) cations are coordinated in a slightly distorted octa-hedral geometry by one 3-tert-butyl-pyridine ligand, one 4-tert-butyl-pyridine ligand and two pairs of translationally-equivalent μ-1,3-bridging thio-cyanate ligands, all of which are in general positions. These μ-1,3-bridging thio-cyante anions bridge the Cd(I...