Structure-activity relationships in reactivators of organophosphorus-inhibited acetylcholinesterase. V. Quaternary salts of hydroxyiminomethylimidazoles.
The methiodides of (E)-1-methyl-2-hydroxyiminomethylimidazole, (E)-1-benzyl-2-hydroxyiminomethylimidazole, and (Z)-1-methyl-5-hydroxyiminomethylimidazole were tested in vitro as reactivators of phosphorylated acetylcholinesterase. From the hydrolysis rate measurements, it was ascertained that only the compounds derived from 2-hydroxyiminomethylimidazole had an activity comparable with that of methiodide of 2-hydroxyiminomethylpyridine, whereas the methiodide of (Z)-1-methyl-5-hydroxyiminomethylimidazole was inactive. The structure-activity relationships of these reactivators are briefly discussed.
Protonenresonanzspektren von Oximen aromatischer Aldehyde
The NMR.-spectra of 9 pairs of isomeric benzaldoximes are discussed. Syn-anti structural assignment is possible using chemical shift data.
THE IRON-ACETOCARMINE METHOD OF FIXING AND STAINING CHROMOSOMES
A short description of this procedure was given in Vol. 55 of the American Naturalist, pp. 573â€”574. The method has now been used almost daily for five years, and certain improvements have suggested themselves. The solution can be prepared by mixing about equal volumes of glacial acetic acid and water. To this is added powdered carmine in excess. The liquid is then â€ ? just brought to boil, cooled, and decanted. To the red solution there are then added a few drops of a solution of ferric hydrate in 50 per cent. acetic acid, to act as a mordant. The amount of iron varies with different objects. Too much produces a precipitate in a short time. The more