Is there anyone prove the results such like the follows?
If $NP\not\subseteq BP(2^{\Omega(n)}),$ then $BPP\subseteq P^{NP}$
In summary, my question it that, can we get some derandomized results based on some nondeterminitic assumptions.
As for derandomization under nondeterministic assumptions, you can basically relativize the usual results such as Impagliazzo-Wigderson. Directly, this gives: if some language in $E^{NP}$ requires exponential circuits with an NP-oracle, then $BPP^{NP}=P^{NP}$. There are similar results by Miltersen and Vinodchandran: if some language in $NE\cap coNE$ requires exponential-size nondeterministic circuits, then $AM = NP$.