UpdatePanel button firing all the validators on the page

I have an Ajax updatePanel  with validation controls in it. There are other controls and validators outside the updatepanel as given below.  When I click the button inside the updatepanel, its firing all validation controls on the page. But I want the user to able to submit ajax button without having to enter the values for the fields outside of UpdatePanel. I will appreciate any help.

ASPX code:

    <form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePartialRendering="true">
        </asp:ScriptManager>
        <asp:UpdatePanel ID="Updatepanel1" runat="server">
            <ContentTemplate>
  & ...