Synthesis and Antimicrobial Activity of New Mannich Bases with Piperazine Moiety

• الحاوية / القاعدة: Molecules
• المؤلفون الرئيسيون: Sara Janowska, Sylwia Andrzejczuk, Piotr Gawryś, Monika Wujec
• التنسيق: مقال
• اللغة: الإنجليزية
• منشور في: MDPI AG 2023-07-01
• الموضوعات: piperazine derivatives; Mannich reaction; antimicrobial activity; antifungal activity
• الوصول للمادة أونلاين: https://www.mdpi.com/1420-3049/28/14/5562

A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from 4-(3-chlorophenyl)-5-(3-fluorophenyl)-2,4-dihydro-3<i>H</i>-1,2,4-triazole-3-thione and different piperazine derivatives. The structures of the products were confirmed by ¹H and ¹³C NMR and elemental analysis. The activity of piperazine derivatives against bacteria (Gram-positive: <i>Staphylococcus epidermidis</i>, <i>Staphylococcus aureus</i>, <i>Micrococcus luteus</i>, <i>Bacillus cereus</i>, and <i>Bacillus subtilis</i>; Gram-negative: <i>Escherichia coli</i>, <i>Pseudomonas aeruginosa</i>, <i>Klebsiella pneumoniae</i>, and <i>Proteus mirabilis</i>) and yeasts (<i>Candida glabrata</i>, <i>Candida krusei</i>, and <i>Candida parapsilosis</i>) was determined by the minimum inhibitory concentration and minimum bactericidal concentration values. Significant activity was observed against Gram-positive bacteria, mainly staphylococci (<b>PG7</b>–<b>PG8</b>) and bacteria of the genes of <i>Micrococcus</i> and <i>Bacillus</i> (<b>PG1-3</b>), as well as selected strains of Gram-negative bacteria, including bacteria of the <i>Enterobacteriaceae</i> family (<b>PG7</b>), while all tested compounds showed high fungistatic activity against <i>Candida</i> spp. yeasts, especially <i>C. parapsilosis</i>, with MICs ranging from 0.49 µg/mL (<b>PG7</b>) to 0.98 µg/mL (<b>PG8</b>) and 62.5 µg/mL (<b>PG1-3</b>). In conclusion, the results obtained confirm the multidirectional antimicrobial activity of the newly synthesized piperazine derivatives. Furthermore, in silico studies suggest that the tested compounds are likely to have good oral bioavailability. The results obtained will provide valuable data for further research into this interesting group of compounds. The library of compounds obtained is still the subject of pharmacological research aimed at finding new interesting biologically active compounds.