Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:4/4
K:Dmin
['D>E F>G A3', 'D2 DC A,4 C2']  
X:1
L:1/8
M:4/4
K:Dmin
 D>E F>G A3 F | G3 F E2 C2 | D>E F>G A3 A | c3 d A4 | c2 d A2 F2 | G3 F E2 C2 | D>E F>G A3 F | 
 AG FE D4 |: D2 DC A,4 | C2 CD E2 C2 | D2 DC A,4 | C2 E2 D4 :|  