| 摘要 |
The present invention relates to novel derivatives of LL-F28249 compounds wherein the pendent C(26,27) olefinic group at C(25) is converted into a 27-bromo or 27-chloro-26-methylene group. The 27-bromo compounds are derived by reacting the LL-F28249 compounds or 5-0-trisubstituted silyl LL-F28249 compounds with N-bromoacetamide or N-bromosuccinimide in aqueous acetone, followed by desilylation for silylated LL-F28249 intermediates. The 27-chloro compounds are prepared by reacting LL-F28249 compounds with N-chlorosuccinimide in methanol. These novel halo compounds have anthelmintic, ectoparasitic, insecticidal, nematicidal and acaricidal activity and are also useful intermediates for the preparation of other novel biologically active compounds. Compositions containing the present compounds as active ingredients thereof are presented. |
