Liquid chromatographic and mass spectral analysis of 1-(3,4-methylenedioxyphenyl)-3-butanamines, homologues of 3,4-methylenedioxyamphetamines

The 1-(3,4-methylenedioxyphenyl)-3-butanamines (HMDAs) are prepared via reductive amination of the corresponding ketone with a series of low molecular weight alkylamines. These amines are homologues of the N-substituted 3,4-methylenedioxyamphetamines (MDAs). Compounds of the HMDA series have UV absorption properties similar to the MDAs because both series contain the same 3,4-methylenedioxyphenyl chromophore. The HMDAs are separated via reversed-phase liquid chromatographic methods using a C18 stationary phase and an acidic aqueous acetonitrile mobile phase. The mass spectra of these potential designer drugs are very similar to the spectra of the MDA homologues having the same N-substituent.     

Radiochemical studies of some separation methods for phosphorus

Various methods of radiochemical separation were tested for the determination of phosphorus in metals and alloys by neutron activation analysis. Classical methods of separation revealed some defects when they were applied to this problem. Methods using liquid extraction gave low yields and were not reproducible. Methods based on precipitation gave better results, but were not selective enough in most of the cases. Retention on alumina was not possible without preliminary separations We studied a new radiochemical separation based on the extraction of elemental phosphorus in the gaseous phase after reduction at high temperature with carbon. Measurements with radioactive phosphorus showed that the extraction yield is better than 99%.     

The stereochemistry of bicyclo[3.2.1]-octane—XII The photohalogenation of bicyclo[3.2.1]octene-2 derivatives

The light-initiated halogenation of bicyclo[3.2.1]octene-2, its 3-phenyl and 3-bromo derivatives with N-bromosuccinimide and t-butyl hypochlorite resulted in the exclusive formation of the exo-4-halobicyclo[3.2.1]octene-2-derivatives.     

Biomimetic chemistry of xylomollin

Kingiside aglucon ($\text{2}$$\text{b}$) undergoes stereoselective addition of CH₃OH to its C(3,4) enol ether double bond to give a C(1,3,9) diastereomer of xylomollin ($\text{1}$), a secoiridoid aglucon that has insect antifeedant properties.     

Instrumental neutron activation analysis of Elbe river suspended particulate matter separated according to the settling velocities

Suspended particulate matter in Elbe river water near Hamburg has been separated into different fractions by pouring the samples into special sedimentation tubes called Atterberg cylinders. The fractions are obtained by decanting the water after different settling periods, and by filtrating the decanted part. The analysis is done by neutron activation in the absolute mode, after irradiation periods of 5 min and 3 days. Mean settling velocities of the SPM-mass and the elements determined have been calculated.     

ANOXIC PHOTODAMAGE IN THE PRESENCE OF PORPHYRINS: EVIDENCE FOR THE LACK OF EFFECTS ON MITOCHONDRIAL MEMBRANES

Abstract When isolated mitochondria are irradiated in the presence of 50 μg/ml hematoporphyrin or hematoporphyrin derivative in the respiratory medium, the irradiation is at least twenty-fold less effective in impairing the Ca²⁺ pump in the absence of oxygen than in its presence. This result suggests that photosensitization by non oxygen-depending pathways has few or no effects on cell membranes, a result somewhat at variance with those observed with liposomes.     

Disposable sodium electrodes

In this paper we describe a disposable sodium sensor in double matrix membrane technology. This sensor is prepared from filter paper with an evaporated silver conducting line on one side. For insulation the sensor is laminated with a pre-perforated heat-sealing film. A defined volume of an ion-sensitive polymer matrix membrane cocktail is filled into one hole. So an ion-sensitive coated film sensor in double matrix membrane technology is produced. The double matrix membrane is formed by the polymer matrix membrane and by the additional filter paper matrix. The response behaviour of the sodium electrode is comparable with conventional macro ion-selective electrodes. By this technology a mass production of low cost sensors is possible.