H Willitzer

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Synthesis and Antibacterial Activity of Benzoylaminoacyl Penicillins and Related Compounds with and without Acylated Catechol Substituents. Syntheses of benzoyl, cinnamoyl, and benzoylhydrazido glyoxyloyl aminoacyl penicillins with and without acylated catechol substituents by condensation of corresponding acids or acylchlorides with ampicillin or(More)
New ampicillin derivatives were synthesized from glyoxylic acid benzhydrazones by reaction with chloroformates via mixed anhydrides and ampicillin. These compounds were tested in an agar diffusion test against six different bacterial strains and also for their stability against beta-lactamases. Studies about structure-activity relationships have shown, that(More)
The toxicity and the bioavailability of new ampicillin derivatives with glyoxylic acid benzhydrazones as site chain depend on the hydrophobic properties of the site chain. Substituents with lower hydrophobicity (expressed by the hydrophobic substituent constant pi according to Hansch) show a lower toxicity (maximal tolerated doses) and also a lower(More)
The inhibitory action of two antiviral compounds used at the maximum tolerated dosis in a cellular system led to a complete suppression of the infectious mengovirus yield and to a 100% plaque reduction. The products of the RNA polymerase reaction catalyzed by the microsomal-mitochondrial fraction of mengovirus-infected FL cells were analyzed by linear(More)
New ureido, oxamoyl, fumaramoyl and terephthalamoyl derivatives of ampicillin or amoxicillin were synthesized by reaction of acylpenicillines with o-dihydroxy- or o-diacyloxy substituents containing aromatic amines bound over CO- or dicarboxylic groups. Corresponding compounds derived from 3,4-diacetoxyaniline showed significant increase of activity against(More)
Substituted amino pyrazoles were found to exhibit plaque reduction and inhibition of the cytopathic effect of mengovirus on FL cells. Their antiviral activity was not caused by a virucidal effect or by inhibition of viral adsoprtion or penetration but by suppression of the virus multiplication. During a one-step growth cycle maximum suppression of virus(More)
In a screening program using the agar diffusion-plaque inhibition test, 22 out of 27 substituted aminopyrazoles tested showed marked antiviral activity against mengovirus in FL cell cultures. The efficacy of the different derivatives was compared by determining their effect on the yield of infectious virus after a one-step growth cycle. The antiviral(More)
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