abstract |
The present invention provides process for synthesis of 8-methoxy-9H-isothiazolo[5,4-b]quinoline-3,4-diones and 8A,9-dihydro-4aH-isothiazolo[5,4-b]quinoline-3,4-diones of the Formula (A). The substituents R, R5, R6, R7, R8 and R9 are defined herein. The invention also provides novel synthetic intermediates useful in the synthesis of 8-methoxy-9H-isothiazolo[5,4-b]quinoline-3,4- diones and 8A,9-dihydro-4aH-isothiazolo[5,4-b]quinoline-3,4-diones. |