Get list of files from FTP server
ncftpls ftp://yourftpserver/dir/*.pdf
Note that patterns such as *.pdf, etc. in the above command do work as expected.
For recursive, use -R. For more options, see man ncftpls.
ncftpls is provided by the ncftp package. For RHEL, this package is available in the epel repo.
With curl, this is handycurl ftp://yourftpserver/dir/ --user username:password
Try to configure ftp to use the PASV (passive) mode for data transfers. This done with the -p switch.
I'm not sure if you will be able to do a recursive file listing with this ftp-client. ls -R in my case just gave the list of files and directories in the current working dir. Maybe Recursive FTP directory listing in shell/bash with a single session (using cURL or ftp) will help you.