How to override HandleUnauthorizedRequest in ASP.NET Core?

I'm migrating my project to asp.net core and I'm stuck in migrating my CustomAuthorization attribute for my controllers. Here is my code.

public class CustomAuthorization : AuthorizeAttribute
{
    public string Url { get; set; }

    protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
    {
        if (!filterContext.HttpContext.User.Identity.IsAuthenticated)
        {
            filterContext.Result = new RedirectResult(Url + "?returnUrl=" + filterContext.HttpContext.Request.Url.PathAndQuery);
        }
        else if (!Roles.Split(',').Any(filterContext.HttpContext.User.IsInRole))
        {
            filterContext.Result = new ViewResult
            {
                ViewName = "AcessDenied"
            };
        }
        else
        {
            base.HandleUnauthorizedRequest(filterContext);
        }
    }
}

then i used it to my controllers

[CustomAuthorization(Url = "/Admin/Account/Login", Roles = "Admin")]
public abstract class AdminController : Controller { }

so, basically i can use it to redirect to different login page when roles is not met. I have few areas and each of them have different login page.