Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/8
M:4/4
K:Bmin
['(3BBB Bc dcBA BABc', '(3BBB (3ddd fd egfe dfed cAAc d2']  
X:1
L:1/8
M:4/4
K:Bmin
|: (3BBB Bc dcBA | BABc dcBA | FAEA FAEA | FABc dcBA | (3BBB Bc dcBA | BABc dcde | fa (3aaa afdf | 
 egfe dB (3BBB :: (3ddd fd egfe | dfed cAAc | d2 fd efge | fdec dBBc | Adfd ecAG | FAdf efge | 
 fa (3aaa afdf | egfe dB (3BBB :|  