Fatal Error On Acivation

I have been using Active Directory Integration 1.1.8 successfully but I recently changed to a MultiSite Installation and needed support for MultiSite.

I deactivated Active Directory Integration 1.1.8 and then installed Next Active Directory Integration 2.0.7. When I attempted to Network activate Next Active Directory I received the following error:

Plugin could not be activated because it triggered a fatal error.

Parse error: syntax error, unexpected ‘.’, expecting ‘,’ or ‘;’ in /var/www/html/forms/wp-content/plugins/next-active-directory-integration/classes/Core/Logger.php on line 22

I checked the file in question and line 22 is referencing the log file:

const LOG_PATH = NEXT_AD_INT_PATH . ‘/’ .’logs/debug.log’;
const FILE_CONVERSION_PATTERN_FILTER = ‘next_ad_int_file_conversion_pattern_filter’;
const ECHO_CONVERSION_PATTERN_FILTER = ‘next_ad_int_echo_conversion_pattern_filter’;

Any ideas?