title: Regex Match Ampersand but not escaped xml characters
body: <p>I would like to match ampersand (&amp;) but not when it exists in following manner</p>
  
  <pre><code>&amp;apos;
  &amp;quot;
  &amp;gt;
  &amp;lt;
  &amp;amp;
  &amp;#
  </code></pre>
  
  <p>So in the following line
      <code>&amp; MY&amp; NAME IS M&amp;Hh. &amp;apos; &amp;quot; &amp;gt; &amp;lt; &amp;amp; &amp;# &amp;&amp;&amp;&amp;&amp;&amp;</code>  </p>
  
  <p>I want it to match all ampersands except those which exist in 
      <code>&amp;apos; &amp;quot; &amp;gt; &amp;lt; &amp;amp; &amp;#</code></p>