<?php

$string = '{\rtf1\ansi\ansicpg1252\deff0\deflang2057{\fonttbl{\f0\fnil\fcharset0 Tahoma;}} \viewkind4\uc1\pard\lang1033\f0\fs17 ASSEMBLE COMPONENTS AS DETAILED ON DRAWING.\lang2057\fs17\par}';
echo preg_replace('#(\{.*\})|\}|(\\\\\S+)#', '', $string);
?>