"defiant towards" is correct and usable in written English.
You can use it when describing someone expressing opposition or resistance to something. For example, "The protestors stood defiant towards the oppressive government policies."
Towards the end of this passionate book in praise of Enlightenment values the author sounds a defiant but plaintive note.
It is staunchly pro-US, but has a sometimes defiant stance towards other European partners, which has created tensions in the past with the EU and neighbouring Germany.
In that moment, her statement was a freedom-cry, a deep and cleansing exaltation and a defiant stride towards well-being.
Tense, fearful and beset by self-doubt, the French seem in a state of defiant hostility: towards their president, political parties, Islam, immigrants, the euro, globalisation, business bosses and more.
Accustomed to being slightly on the margins of church hierarchy, the Jesuits are marked out by a questioning and occasionally defiant attitude towards the central office of the church.
The next month the family appeared to be reunited, according to a report which described the father yelling at his daughter after she engaged in "defiant behaviour" towards staff, warning that Safe the Children might take her away from him.
While members of his 1974 tour group, including future wife Olivia Arias, have spoken of Harrison's defiant attitude towards the negative reviews, Leng suggests that he "reacted to them as personal attacks".
Other co-workers had disrespectful and defiant attitudes towards theirs superiors.
Although admittedly the thésards I spoke to were a small sample, they expressed remarkably similar pride in their thesis work, which then segued – spontaneously for some, for others in response to my questions – into ambivalent, resentful or even defiant attitudes towards current or future employment in commercial work.
