tinymce - Tinymice editor strips <![endif --> tags

In um email templates i have used if mso tags to render a different logo image.

this is the sample code i have used. However everytime i save the template wordpress converts my <!–<![endif]–> into ‘& l t;!– . How can i avoid this.

<!--[if !mso]><!-->
            <img src="logo.png" alt="">
 <!--<![endif]-->

I tried using [‘entity_encoding’] = ‘raw’ setting in tinymice but no avail

Any help would be highly appreciated