Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
Q:1/4=120
M:4/4
K:Amin
['B2 c2', 'c4 c4 z2 cd e2 c2 B3']  
X:1
L:1/8
Q:1/4=120
M:4/4
K:Amin
|:"^A""^f" z2 e>f edd^c | d^cde f4 |"^c" f2 d>e dccB | cBcd e4 | e2 c>d edcB |"^f" d2 z c BA^GF | 
 B>c BAA^G |1 (3A^GA (3BAB c2 d2 :|2 A6 z2 |[M:7/8]"^B""^f" E2 c B2 A2 | B2 A ^G2 F2 | 
"^c" E2 F ^G2 A2 |"^f" B2 c2 B3 |"^c" z EE E2 c2 | c2 BA c3 | BA B2 c2 | e6 z |: 
[M:4/4]"^C""^f" e<f e2 e2 | d2 c2 B4 | B2 c2 d4 | d4 | d<e d2 d2 | c2 B2 A4 | B2 c2 c4 | c4 z2 cd | 
 e2 c2 B3 A | ^GF E2 z2 Bc |1 BAA^G A2 B2 | c4 d4 :|  