Consider the following premises. s -> t. q or ~t. t <-> q. Can we infer ~(s -> q) from them?
 From t <-> q we can infer q -> t. From q or ~t we can infer t -> q. From q -> t, t -> q we can infer q <-> t. From q <-> t we can infer t -> q. Finally, from s -> t, t -> q we can infer s -> q, which contradicts ~(s -> q). Therefore, the answer is no.