F♯ over Cm (major triad over minor triad a tritone apart).
C        E♭          G        A♯       C♯             F♯    
1        ♭3          5        ♭7       ♭9             ♯11         

Parent scales are B♭ diminished (no ♭5 or 7) or C♯ diminished (no ♭3 or ♯5) or E diminished (no 1 or 4) or G diminished (no 2 or 6).
C  C♯    E♭     F♯ G        A♯
1  ♭2    ♭3     ♯4 5        ♭7

Related chords.
| A13♯9 (no 1 or 5) | C7♭9♯11 (no 3 or 6) | E♭13♯9 (no ♭9 or ♯4) | F♯7♭9♯11 (no ♯9 or ♭7) |