Synthesis and 1H NMR studies of 3-(d-erythro-glycerol-1-yl)-1H-pyrazolo[3,4-b]quinoxaline and its 7-chloro and 7-methyl analogues Original Research Article

3-(d-erythro-Glycerol-1-yl)-1H-pyrazolo[3,4-b]quinoxaline and its 7-chloro and 7-methyl analogues (11 and 12) were prepared from the corresponding quinoxalines. The 7-substituted analogues 11 and 12 were obtained as the preponderant isomers, and the 6-substituted analogues as the minor isomers. The structure and position of the substituent were determined by 1H NMR studies. The effect of substitution on the chemical shift of other protons is discussed.