在N,N-二甲基乙酰胺(DMAc)中,反-β-正烷氧羰基丙烯酸(1a-1h,a-h分别对应于C1-C8正烷氧羰基)与SOCl2在0℃下反应,生成的酰氯不经分离,采用一锅法,直接与L-抗坏血酸反应得到反-β-正烷氧羰基丙烯酸-6-L-抗坏血酸酯(2a-2h)。2a-2h的结构经1 H NMR、13 C NMR、MS和IR确证。用分光光度法测试了2f清除二苯代苦味肼基自由基(DPPH·)的活性,用孔穴扩散法测试了2a-2h的抗菌活性。结果表明,受试物摩尔浓度相等时,在较高浓度范围内,2f对DPPH·的清除率略高于L-抗坏血酸和叔丁基对苯二酚(TBHQ)；在给药量2 mg·mL-1时,2a-2h对金黄葡萄球菌、大肠杆菌、枯草芽孢杆菌的抑菌圈直径在5．00-6．25 mm之间,对细黄链霉菌的抑菌圈直径在15．50-17．25 mm之间。%A general one-pot procedure was described that converted trans-β-n-alkoxycarbonyl( C1-C8 n-alkoxycarbonyl) acrylic acid (1a-1h)to 6-L-ascorbyl trans-β-n-alkoxycarbonyl acrylates(2a-2h) upon sequential treatment of the acid in N,N-dimethylacet-amide(DMAc)with thionyl chloride and L-ascorbic acid. The structures of 2a-2h were confirmed by 1H NMR、13C NMR、MS and IR. The scavenging activity of 2f on DPPH free-radical was tested by UV-Vis spectrophotometry,and the anti-microbial activities of 2a-2h were tested by peptide-agarose diffusion assay. It was fond that when the molar concentration of the tested samples was the same,the scavenging activity on DPPH radical(1,1-Diphenyl-2-picrylhydrazyl radical)of 2f was a little higher than that of L-ascor-bic acid and TBHQ(Tertiary butylhydroquinone)at higher concentration range. The diameters of antibacterial active ring of 2a-2h against Staphyloccocus aureus,Escherichia coli and Bacillus subtilis were between 5. 00-6. 25 mm,and those of 2a-2h against Streptomyces microflavus were between 15. 50-17. 25 mm,when the concentration of tested samples were in 2 mg·mL-1 .
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