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.
New 5-Substituted Derivatives of Ethyl 2,3-Dihydro-3-oxoisothiazolo[5,4-b]pyridine-2-acetate
摘要:
New series of ethyl 5-substituted 2,3-dihydro-3-oxoisothiazolo[5,4-b] pyridine-2-acetate was prepared either a) directly by reaction of 5-substituted 2-chlorothio-3-pyridinecarbonyl chlorides with ethyl glycinate or b) by oxidation of the correspondent 2-mercapto-3-pyridinecarboxamides. New 5-substituted 1,2-dihydro-2-thioxo-3-pyridinecarboxylic acids as starting materials are described.