Biocidal compounds and their preparation

Abstract

This invention concerns new biocidal compounds of formula (I) wherein R is H or CH 3 . Of particular interest are two isomers that are named malayamycin A and desmethylmalayamycin A. These isomers, which may be prepared by growing under controlled conditions a previously unknown strain of micro-organism from the species Streptomyces malaysiensis , are characterised by nmr and mass spectroscopic data. They have biocidal activity, including anti-fungal, anti-viral and anti-cancer activity, and are of special interest for use in agriculture, horticulture, animal and human health.

1 . A compound having the formula (I)  
       
         
           
           
               
               
           
         
       
       wherein R is H or CH 3 .  
     
     
         2 . A compound according to  claim 1  having the formula (II)  
       
         
           
           
               
               
           
         
       
     
     
         3 . A compound according to  claim 1  having the formula (III)  
       
         
           
           
               
               
           
         
       
     
     
         4 . A compound according to  claim 1  in the form of a whole fermentation broth containing such a compound; the solids of a whole fermentation broth containing such a compound; intact or lysed mycelia separated from a whole fermentation broth containing such a compound; the solids of such a whole fermentation broth containing such a compound after separation of intact or lysed mycelia; or such a whole fermentation broth containing such a compound after the separation of solids and the mycelia.  
     
     
         5 . A biocidal composition comprising a biocidally effective amount of a compound as claimed in any one of the preceding claims.  
     
     
         6 . A composition according to  claim 5  wherein said composition is a fungicidal composition comprising a fungicidally effective amount of a compound of formula (I) and a suitable carrier or diluent therefor.  
     
     
         7 . A method of combating and controlling fungi which comprises treating the fungi or the locus of the fungi with a composition according to  claim 6 .  
     
     
         8 . A method of combating or controlling phytopathogenic fungi according to  claim 7  which comprises applying a fungicidally effective amount of a compound of formula (I), or a composition containing a compound of formula (I), to a plant, to a seed of a plant, to the locus of the plant or seed or to soil or any other plant growth medium, e.g. nutrient solution.  
     
     
         9 . A process for the production of a compound of formula (I) which comprises the step of cultivating an organism of the strain  Streptomyces malaysiensis  capable of producing a compound of formula (I) whereby said compound is produced, and if desired isolating said compound therefrom.  
     
     
         10 . A process according to  claim 9  wherein said strain is  Streptomyces malaysiensis  JHCC 553434 (DSM 14702) or a mutant thereof.  
     
     
         11 . A process according to  claim 9  in which a compound of formula (I) is separated from the fermentation broth.  
     
     
         12 .  Streptomyces malaysiensis  JHCC 553434 (DSM 14702) and mutants thereof.  
     
     
         13 . A process for combating fungi or viruses or cancer cells comprising exposing said viruses or fungi or cancer cells to a compound of formula (I) according to  claim 1 .  
     
     
         14 . (canceled)  
     
     
         15 . A method of controlling fungal infection of a plant or part thereof said plant having been genetically modified to enhance resistance to fungi either by selective breeding and/or preferably by genetic modification where one or more DNA sequences, the expression of which enhances the resistance of the plant to fungi, have been introduced into said plant using recombinant DNA techniques, said method comprising exposing said plant or part thereof to a compound of formula (I) according to  claim 1 .  
     
     
         16 . A method of controlling viral infection of a plant or part thereof said plant having been genetically modified to enhance resistance to viruses either by selective breeding and/or preferably by genetic modification where one or more DNA sequences, the expression of which enhances the resistance of the plant to viruses, have been introduced into said plant using recombinant DNA techniques, said method comprising exposing said plant or part thereof to a compound of formula (I) according to  claim 1 .  
     
     
         17 . (canceled)  
     
     
         18 . (canceled)  
     
     
         19 . (canceled)  
     
     
         20 . (canceled)