Unavailing (adjective)

1. Not producing the desired result or outcome.
2. Ineffective or futile.

Origin:

Derived from the prefix 'un-' meaning 'not' and 'availing' meaning 'producing the desired result or outcome.'.

Examples:

1. The unavailing efforts to save the drowning man were heartbreaking.
2. The unavailing search for the missing child ended with no results.
3. The unavailing attempts to fix the broken machine only made the problem worse.
4. The unavailing negotiations between the two countries resulted in a stalemate.
5. The unavailing remedies for the patient's illness proved ineffective.