Antimicrobial Activity and Synthesis of Sydnonyl－－Substituted Pyrazoline Derivatives

合成雪梨酮取代吡唑啉衍生物及其抗菌活性探討

利用適當的α,β─不飽和酮先導物4和水合肼作用，可順利的合成一些新的雪梨酮取代─1氫─吡唑啉衍生物5。本研究將所合成的1氫─吡唑啉衍生物5a-r採用濾紙圓片平板法，試驗對細菌及黴菌增殖之阻抗性。所採用之試驗細菌有四種：金黃色葡萄球菌(Staphylococcus aureus)、變形桿菌(Proteus vulgaris) 、大腸桿菌(Escherichia coli)、綠膿桿菌(Pseudomonas aeruginosa)，所使用之標準抗生素為諾氟沙星(Norfloxacin)；而黴菌方面之試驗菌種有二種：黑麴菌(Aspergillus niger)及檸檬青黴菌(Penicillium citrinum)，而標準抗黴菌劑為吉膚黴素(Griseofulvin)。試驗結果發現，雖然所合成的吡唑啉化合物5a-r對於所選擇之四株細菌無明顯阻抗能力，但對兩株黴菌却具有明顯的成長抑制力，其中化合物5i和5l對檸檬青黴菌的阻抗力，足以與標準品吉膚黴素匹敵；而化合物5l和5o對黑麴菌具有超强的阻抗力。值得留意的是所有吡唑啉化合物對黑麴菌之阻抗力與標準品吉膚黴素比對，其相對抑制力達到1.4-2.8倍，而且在這些試驗化合物中，以化合物5l顯現同時對兩株黴菌，黑麴菌和檸檬青黴菌，具有最佳抗菌活性。

Some new 1H-pyrazoline derivatives 5 were synthesized successfully through the reactions of appropriate α, β-unsaturated ketone precursors 4 and hydrazine hydrate. All the synthesized 1H-pyrazoline products 5a-r were screened by paper-disc method to identify their antimicrobial activities against four bacteria viz. Staphylococcus aureus, Proteus vulgaris, Escherichia coli and Pseudomonas aeruginosa, and two fungal cultures viz. Aspergillus niger and Penicillium citrinum. The reference drugs were Norfloxacin and Griseofulvin, respectively. The screening data indicated that the tested compounds 5a-r exhibited no obvious antibacterial activity compared with the standard drug Norfloxacin. However, compounds 5a-r displayed significant antifungal activities against both fungi. In the test, compounds 5i and 5l exhibited the potent antimicrobial activity against Penicillium citrinum, comparable to that of standard antifungal drug Griseofulvin. Compounds 5l and 5o had the strongest antifungal activity against Aspergillus niger. Notably, all of the tested compounds showed growth inhibitory activity 1.4-2.8 times higher than that of the standard drug Griseofulvin against Aspergillus niger. Among these pyrazoline derivatives, compound 5l displayed the strongest antimicrobial activity against both of fungi, Aspergillus niger and Penicillium citrinum.