| abstract |
NEW MATERIAL:The compound of formula I [R<1> is methyl, ethyl, isopropyl or sec-butyl; X is =CHR<2> (R<2> is H or lower alkyl), =N-OR<3> is H, methyl, benzyl or lower alkanoyl) or =N-NHCONR<2>R<3>]. EXAMPLE:13-Hydroxy-5-ketomilbemycin A4 5-oxime. USE:A miticide, insecticide, anthelminthic or intermediate for the synthesis of compound useful as the above pesticides. PREPARATION:The compound of formula II (e.g. 5-ketomilbemycin A4 5-oxime) is treated with a selenium dioxide in the presence of a carboxylic acid of formula R<4>-COOH (R<4> is H or lower alkyl) (e.g. formic acid) to obtain the compound of formula I or formula III. If necessary, the obtained compound of formula III is hydrolyzed. |