The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 04, 1993
Filed:
Mar. 28, 1991
Peter T Meinke, New York, NY (US);
Helmut Mrozik, Matawan, NJ (US);
Merck & Co., Inc., Rahway, NJ (US);
Abstract
Avermectin derivatives are disclosed wherein the 4'-hydroxy group is replaced by a substituted alkylthio or acylthio group or an iodo group. These avermectin derivatives can be further derivatized at the 5- and 23-positions as ketoximes or O-substituted ketoximes. The 4'-substituted avermectin derivatives are prepared from the 4'- and 4'-trifluoromethanesulfonyl avermectin derivatives with halo- or sulfur-containing nucleophiles. The 4'- and 4'-.alpha.- and .beta.-trifluoromethane sulfonates are prepared selectively and converted into 4'- or 4'-alkyl- or acylsulfides, or iodides using the appropriate sulfur-containing or iodine nucleophile. Substituted sulfoxy and sulfonyl substituents at the 4'- and 4'-positions are prepared from oxidation of the corresponding substituted sulfides. The new compounds are potent anti-parasitic agents; in particular, the compounds are anthelmintic, insecticidal and acaricidal agents.