B. M. Goldschmidt

The preparation and determination of structure of benzylpenicilloyl compounds used in skin-testing for penicillin allergy.

Susceptibilities of 227 strains of 34 bacterial species to cefatrizine (CFT) were determined by the 2-fold agar dilution method in parallel with the diameter of inhibition zones by the single-disc method, under the experimental condition established by Kanazawa. The experiments demonstrated significant correlation between MIC by the dilution method and diameter of inhibition zone in each of conventional assay of the over-night (about 16 hours) incubation, delayed assay (about 24 hours incubation), and rapid assay (after 3-4 or 5-6 hours incubation), thus confirming applicability of the single-disc assay for CFT. Analysis of the data obtained by using CFT disc containing 30 micrograms revealed the primary regression equation to be: D (diameter, mm) = 25.6--9.6 log MIC (micrograms/ml) in conventional assay, D = 33.2--13.2 log MIC (micrograms/ml) in delayed assay, D = 15.8--4.7 log MIC (micrograms/ml) in 3-4 hours rapid assay and D = 20.2--7.0 log MIC (micrograms/ml) in 5-6 hours rapid assay, respectively. The range of variations in MICs estimated from the diameter of inhibition zone by the disc test was then calculated in comparison with that in MIC determined by the 2-fold agar dilution assays, as reference for the experimental errors which may be involved in the estimation of MIC of CFT by the single-disc assay.

The synthesis and aggregation of 9-phenyl- and 9-s-butyl-3,6-bisdimethylaminoacridine in solution. The dealkylation of 9-t-butylacridans

9-Butyl-(Id) and 9-phenyl-3,6-bisdimethylaminoacridan (If) have been synthesised and oxidised to their aromatic analogues (IIc) and (IId). 3,6-Bisdimethylamino-9-t-butylacridan (Ie) and 9-t-butylacridan (Ib) undergo oxidative dealkylation in the 9-position when treated with various oxidising agents. The absorption and fluorescence spectra of the two 9-substituted 3,6-bisdimethylaminoacridines have been examined and compared with that of 3,6-bisdimethylaminoacridine under a variety of conditions, and the binding of these three dyes to inorganic polyphosphate at various polymer–dye ratios has been examined spectroscopically.

Cyclisation and C-acylation of 2,6-dioxocyclohexylacetic acids

The βγ-unsaturated γ-lactones, 2-hydroxy-6-oxocyclohex-1-enylacetic acid lactone and 2-hydroxy-4,4-dimethyl-6-oxocyclohex-1-enylacetic acid lactone undergo acylation on the carbon atom adjacent to the lactone carbonyl group on treatment with acetic anhydride in the presence of sodium acetate. The structures of these compounds were determined by nuclear magnetic resonance, ultraviolet and infrared spectroscopy, and by decarboxylation of the acylated gem-dimethyl compound to a known ketone. The βγ-unsaturated lactones were not isomerised to αβ-unsaturated lactones under a variety of reaction conditions.