[E-Z ratio and stability of halogenated benzylidene derivatives formed during the detection of glycine conjugates]. / E/Z-Verhältnis und Stabilität der beim Nachweis von Glycinkonjugaten entstehenden halogenierten Benzylidenverbindungen.

The orange fluorescing spot formed during the detection of halogenated hippuric acids with 4-N,N-Dimethylaminobenzaldehyde on TLC-plates consists of a E/Z-mixture of the corresponding benzyliden derivatives. Intermediates are the azlactones.

[Cleavage and biotransformation of the central muscle relaxant chlormezanone]. / Spaltung und Biotransformation des zentralen Muskelrelaxans Chlormezanon.

Chlormezanone, a chiral centrally acting muscle relaxant, will be cleaved at its S-C-1 bond by an autoprotolytic process. The optimum of chemical stability exists between pH 2 up to pH 9 with a maximum at pH 7.4. The plasma half life at 37 degrees C is 76 h. Enzymes do attack the products of cleavage namely 4-chlorobenzaldehyde and 2-carboxyethane-sulfinic-acid-N-methyl-amide. The main metabolite in urine is 4-chlorohippuric acid in the range of up to 70% of the oral administered dose to humans. No cytochrome P-450 is engaged in the cleavage of the S-C-bond.

[Fast thin-layer densitometric determination of the nootropic piracetam in biological material]. / Rasche dünnschicht-densitometrische Bestimmung des Nootropikums Piracetam in biologischem Material.

After oral doses of piracetam this drug is detectable in serum as well as in urine after formation of the red Fe(III)-hydroxamatecomplex by thin-layer densitometry. Detection in serum requires extraction with a mixture of dichloromethane/ methanol, while urine can be used directly after dilution. The limit of quantification in urine is 100 micrograms/ml and in serum 4.0 micrograms/ml. The new method was validated by HPLC. The coefficient of correlation was 0.9999% for determination in urine and 0.9986% for determination in serum.