Homebrew putty installation does not make the putty command recognisable
Update: Current stable version (.67) of putty can't be build with gtk+2 support on OS X using homebrew. This is a know issue #40951. It seems you can install from HEAD version (brew install --HEAD --with-gtk+3 putty) and for me that is also broken.

brew install putty by default installs from a pre-built bottle. The pre-built bottle for putty doesn't include putty, puttytel or pterm.

If you want putty then can try installing from source. First remove the installed putty formula by running brew remove putty. After that install putty from source by running brew install --build-from-source --with-gtk+3 putty.

NOTE: As of this writing building putty from source is broken with homebrew

If someone is getting an error like this: invalid option: --with-gtk+3, all installation options are removed with the latest version of the brew. source