The D# minor scales share most of their notes with the F# major scale. Both keys have six sharps in the key signature.
Here are the D# minor harmonic scales. The raised 7th note of the scale is CX (C double sharp) which is an enharmonic equivalent of the note D natural. You must use C double sharp (not D) when writing a scale or music in the key of D# minor. The interval between the B and C double sharp is an augmented 2nd.
Here are the D# minor melodic scales. They use B# and C## on the way up, but C# and B natural on the way down.
C## is the leading note and is part of the dominant chord (G# major), so it usually appears quite a lot in music written in the key of D# minor, however, not much music is actually written in this key. You are most likely to encounter D# minor as key change in a piece that starts in a different key.
This extract is from a song by Schubert called “Auf dem Flusse” (On the River). The piece begins in E minor, until bar 8. When the second line of text begins in bar 9, the key suddenly changes to D# minor. D# minor is the key one semitone lower than E minor, and Schubert uses it to emphasise the negative feelings in the text.
E Flat Minor
The Eb minor scales share most of their notes with the Gb major scale. Both keys have six flats in the key signature.
Here are the Eb minor harmonic scales. The raised 7th degree of the scale is D natural, so when the scale is written without a key signature, no accidental is needed. The interval between the Cb and D natural is an augmented 2nd.
Here are the Eb minor melodic scales. They use C and D natural on the way up, but Cb and Db on the way down. Melodic minor scales do not include any augmented 2nds.
Here is the beginning of Bach’s Prelude in Eb minor from the Well-Tempered Klavier, Book 1. Notice the use of D natural, which is the leading note in Eb minor.