There is no D# in the key of Cm...

[kbold]

What about the E minor melodic scale, where the 7th is sharp on the way up (D#) and natural on the way down?

E F# G A B C D# E D C B A G F# E

E Melodic Minor has C# (not C)

That aside, I was thinking along the same lines.
Since the original post mentioned Cm (i.e. not labelling it as C Natural Minor), we can include the Melodic and Harmonic Minor scales.

In the Harmonic Minor series, the 6th degree of E Harmonic Minor is C Lydian#2 (i.e. a HM mode, which is still a minor scale with a #2 (enharmonic b3 ))
So C Lydian#2 does have a D# (C D# E F# G A B)

 

[daddyplaysbass]

I think in the key of Cm; D# is just a demolished chord