Abstract
         
         For the structure-activity relationship study on berberrubine derivatives, a series
            of compounds bearing 9-O-acyl- and 9-O-alkyl-substituents were synthesized and tested for antimicrobial activity against
            Gram-positive, Gram-negative bacteria and fungi. Octanoyl, decanoyl, lauroyl derivatives
            among the acyl analogs and hexyl, heptyl, octyl, nonyl, decyl, undecyl derivatives
            among the alkyl analogs showed strong antimicrobial activity against Gram-positive
            bacteria and fungi. As a whole, alkyl analogs were more active than acyl analogs for
            antimicrobial activity. Synthesized derivatives had no activity on Gram-negative bacteria.
            Too short or too long substituents decreased activity. These results suggest that
            the presence of lipophilic substituents with moderate sizes might be crucial for the
            optimal antimicrobial activity.
         
         
    
   
      
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         Dr. J. H. Kim
            Department of Biotechnology
            
            College of Engineering
            
            Yonsei University
            
            134 Shinchon-dong
            
            Seoul 120-749
            
            Korea
            
            Email: junghan@bubble.yonsei.ac.kr
            
            Fax: +822-362-7265