Adapted from https://rtcamp.com/wordpress-nginx/tutorials/multisite/subdomains/minimal/

Nginx WordPress Single Site or Multisite Subdomain config

server {
        ##DM - uncomment following line for domain mapping	
        #listen 80 default_server;
	server_name example.com *.example.com ;
	##DM - uncomment following line for domain mapping
	#server_name_in_redirect off;

	access_log   /var/log/nginx/example.com.access.log;
	error_log    /var/log/nginx/example.com.error.log;

	root /var/www/html/example.com;
	index index.php;
	
	# Add trailing slash to */wp-admin requests.
	rewrite /wp-admin$ $scheme://$host$uri/ permanent;

	location / {
		try_files $uri $uri/ /index.php?$args ;
	}

	location ~ \.php$ {
                try_files $uri =404;
                fastcgi_split_path_info ^(.+\.php)(/.+)$;
                #NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini

                include /etc/nginx/fastcgi_params;
		fastcgi_pass unix:/tmp/php-fpm.sock;
                fastcgi_index index.php;
                fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
	}

	location ~* ^.+\.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|rss|atom|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ {
		access_log off;	log_not_found off; expires max;
	}

	location ~ /\. { deny  all; access_log off; log_not_found off; }

        # This should match upload_max_filesize in php.ini
        client_max_body_size 20M;
}

Looks like a missing semi-colon on line 37