Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/4
M:3/4
K:Dmin
['', 'A/ (3A (d ^c) A7/8c/8 (3e (g', '(3e (a g) e/>g/']  
X:1
L:1/4
M:3/4
K:Dmin
 A/ |: (3A (d ^c) A7/8c/8 | (3e (g e) f7/8f/8 | (3f a g e/>g/ |1 f e- e/A/ :|2 f e2 |: 
 (3e (a g) e/>g/ | (3f f d e | (3e (a g) e/>g/ | (3f (f d) e/>e/ | (3e (a g) e/>g/ |1 f e2 :|2 
 e d2 |]  