Five trisubstituted quinazolones and eight trisubstituted quinazoline-4-thiones have been tested for antibacterial effects by a microdilution method. Four derivatives exerted a significant effect on E. coli, P. aeruginosa, S. aureus and B. subtilis (IC50 < 100 mg/L). In the bacterium P. aeruginosa six quinazolines showed a higher antibacterial effect than ampicillin. The most sensitive to the effects of the quinazolines was S. aureus; a concentration of 100 mg/L of six derivatives induced a bacteriostatic effect on S. aureus. The quinazoline-4-thiones were generally more active than the quinazolones. All the tested concentrations of the four most effective quinazolines influenced the specific growth rate.

• MeSH
• Anti-Bacterial Agents pharmacology   MeSH
• Bacillus subtilis drug effects   MeSH
• Bacteria drug effects   growth & development   MeSH
• Quinazolines chemistry   pharmacology   MeSH
• Escherichia coli drug effects   MeSH
• Microbial Sensitivity Tests MeSH
• Pseudomonas aeruginosa drug effects   MeSH
• Staphylococcus aureus drug effects   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH
• Names of Substances
• Anti-Bacterial Agents MeSH
• Quinazolines MeSH

Eleven substituted tricyclic quinazolines and their synthetic precursors were tested for antibacterial effects. 3-Chloromethylcarbonyl-2-methylquinazolin-4-thione and 5-phenyl-2,3-dihydro-1,2,4-triazolo[4,3-c]quinazolin-3-one had the highest antibacterial effect against Bacillus subtilis, the MIC values being 50 mg/L. Two tested derivatives were more active against Pseudomonas aeruginosa than ampicillin, the IC50 values being 80 and 100 mg/L. The most effective derivatives contained in the structure generally pharmacologically active chromophores--methyl group in position 2 and a chloromethyl configuration on the carbonyl group in position 3.

• MeSH
• Anti-Bacterial Agents chemical synthesis   chemistry   pharmacology   MeSH
• Bacillus subtilis drug effects   MeSH
• Bacteria drug effects   MeSH
• Quinazolines chemical synthesis   chemistry   pharmacology   MeSH
• Escherichia coli drug effects   MeSH
• Microbial Sensitivity Tests MeSH
• Pseudomonas aeruginosa drug effects   MeSH
• Staphylococcus aureus drug effects   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Anti-Bacterial Agents MeSH
• Quinazolines MeSH

Two synthetic 2,6-disubstituted 4-anilinoquinazolines exerted a significant effect on the G+ bacteria Bacillus subtilis and staphylococcus aureus. None of 12 tested derivatives influenced Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa. Derivatives having the aromatic ring non-substituted or substituted by bromine, the pyrimidine ring by phenyl, morpholine or piperidine and the aniline skeleton non-substituted or substituted by methyl or amino group exerted a considerable antibacterial activity.

• MeSH
• Aniline Compounds chemistry   pharmacology   MeSH
• Anti-Bacterial Agents chemistry   pharmacology   MeSH
• Drug Resistance, Microbial MeSH
• Bacillus subtilis drug effects   MeSH
• Quinazolines chemistry   pharmacology   MeSH
• Microbial Sensitivity Tests MeSH
• Staphylococcus aureus drug effects   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Aniline Compounds MeSH
• Anti-Bacterial Agents MeSH
• Quinazolines MeSH