c# get object's property which contains IList and retrieve its custom attribute

I have a situation below:

public class A{
    public IList<B> bs { get; set; }
    public C c { get; set;}
}

[CustomAttribute]
public class B{
}

[CustomAttribute]
public class C{
}

I get a list of various entities into an array and then I need to check if any entity's property has custom attribute defined.

    for (int i = 0; i < e.Count; i++) {
     Type obType = e[i].GetType();
     if (!obType.GetCustomAttributes(typeof(CustomAttribute)).Any()) {
      /*get all properties which have CustomAttribute defined on its class 
- in our case we need to get properties for IList<A> and property for C class*/
     }
    }

It seems the real problem is to reterive IList object type and retreive custom attribute.