Enable Disable Bootstrap SelectPicker DropDownList using jQuery in ASP.Net

How do I disable or remove the validate [required] class from a select picker bootstrap control annex code of how I try to remove it disable it with jquery but it didn't work

$('#<%=ddlMarca.ClientID %>').removeClass("validate[required]");

<asp:DropDownList ID="ddlMarca" runat="server" class="form-control selectpicker validate[required]"