Used as a phosphorylating agent in organic synthesis, particularly for introducing phosphate groups into nucleosides and sugars. It is effective in the preparation of phosphate esters under mild conditions, making it valuable in the synthesis of biologically active compounds, including antiviral and anticancer agents. Its sulfonate leaving group enhances reactivity, allowing efficient phosphorylation in the presence of mild bases. Commonly applied in medicinal chemistry and nucleotide analog development.