Synthesis of 2-Substituted Isothiazolo[5,4-b]pyridin-3(2H)-one 1,1-Dioxides
摘要:
The Isothiazolo[5,4-b]pyridin-3(2H)-one 1,1-dioxides (3a - g) were prepared from the corresponding isothiazolo[5,4-b]pyridin-3(2H)-ones (1a - g) by means of an oxidation with oxone(R) (KHSO5) and sodium hypochlorite (NaOCl) in two steps. The influence of the substituents (R), in position 2 of this system, on the oxidation process was studied. While the oxidation of 1a - g with 3-chloroperoxybenzoic acid gave yields of 3a - g depending greatly on the nature of R, the combined KHSO5/NaOCl method gave good yields of 3a - g in all of the cases studied.
Heteroaryl-Fused 2-Phenylisothiazolone Inhibitors of Cartilage Breakdown
摘要:
The synthesis, biological evaluation, and structure-activity relationships of a series of N-phenyl heteroaryl-fused isothiazolones are described. These isothiazolones have been shown to exhibit potent, dose-dependent inhibition of IL-1 beta-induced breakdown of proteoglycan in a cartilage organ culture assay. This effect is likely due to inhibition of MMP activation and a consequent reduction in MMP activity following IL-1 beta stimulation. Thus these compounds potentially represent simple, non-peptidic disease-modifying agents for the treatment of arthritic diseases. To examine the effects of structure on in vitro activity, three general features of the molecules were varied, substituents on the pendant N-phenyl group, the position of ring fusion to the isothiazolone, and substituents on the fused ring peri to the isothiazolone sulfur.