4,4′-Benzophenone-O,O′-disulfamate: a potent inhibitor of steroid sulfatase

We investigated whether the benzophenone moiety can be used as core element of steroid sulfatase (STS) inhibitors. While 4- and 3-benzophenone-O-sulfamates inhibit STS with IC50 values between 5 and 7 μM irrespective of additional hydroxy and methoxy substituents at the second phenyl ring, benzophenone-O,O′-disulfamates show increased activity. With an IC50 value of 190 nM the 4,4′-derivative is the first small monocyclic STS inhibitor coming close to the potency of the steroidal standard estrone sulfamate.