The arguments of synchronize command are paths to directories. You cannot use file masks there.

If you want to restrict the synchronization to certain files, you have to use -filemask switch:
synchronize remote -filemask=*.txt C:\ddswrkq\ACEPRMRB\ACMRBSIP /u194/outbox/inq

You must be using some old version of WinSCP. With recent versions, would would get a more helpful message with your wrong syntax. You should upgrade.

I am trying to synchronize *.txt files to the remote server using the below command
synchronize remote "C:\ddswrkq\ACEPRMRB\ACMRBSIP\*.txt" /u194/outbox/inq/

Log always says nothing to synchronize even though there are *.txt files present
Can someone help me with the command. I want to sync only *.txt files from that folder