diff --git a/imap_filter/imap_filter.py b/imap_filter/imap_filter.py
index c100ed5..78cfdf2 100644
--- a/imap_filter/imap_filter.py
+++ b/imap_filter/imap_filter.py
@@ -149,7 +149,7 @@ class ImapFilter:
                 condition = f'allof (header :contains "{field}" "{mfilter['regexp']}")'
             else:
                 condition = f'allof (header :contains "{field}" ["{'", "'.join(mfilter['words'])}"])'
-            search = f'^.*  # imap_filter: rule name \'imap_filter_INBOX_{mfilter['name']}\''
+            search = f"^.*  # imap_filter: rule name 'imap_filter_INBOX_{mfilter['name']}'"
             replacement = f'if {condition} {{ fileinto "{mfilter['destination']}"; stop;}}  # imap_filter: rule name \'imap_filter_INBOX_{mfilter['name']}\''
             new_content = re.sub(search, replacement, content)
             if content == new_content: