This enzyme belongs to the family of transferases, specifically the sulfotransferases, which transfer sulfur-containing groups. The systematic name of this enzyme class is 3'-phosphoadenylyl-sulfate:quercetin-3,3'-bissulfate 7-sulfotransferase. Other names in common use include flavonol 7-sulfotransferase, 7-sulfotransferase, and PAPS:flavonol 3,3'/3,4'-disulfate 7-sulfotransferase.
References
Varin L (1988). "Enzymatic synthesis of sulfated flavonoids in Flaveria spp". Bull. Liaison-Groupe Polyphenols. 14: 248–257.