Use post object from first query in second query

The primary loop query post ID is stored in $current. This variable is equivalent to $post->ID. The secondary loop query post ID is available within the loop as $post->ID. Thus, you just need a simple if statement in side your secondary loop:

<?php 
if ( $current == $post->ID ) {
    // This post is the same as the
    // primary loop's current post;
    // do something
}
?>

For example, to add a “current-article” class, I’d try the following on the <li>

<li<?php if ($post->ID == $current) echo 'class="current-article"'; ?>><!-- stuff here --></li>