Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/4
M:3/4
K:Emin
['B2 B/>c/ B', 'd2 ^c/>e/', '(f2 a)']  
X:1
L:1/4
M:3/4
K:Emin
 g/>f/ | e ^d e | B2 B/>c/ | B A G | F2 F/>G/ | F A c | B2 B/>c/ | B g f | e2 :: B/>c/ | 
 d2 ^c/>e/ | d2 ^c/>e/ | d g f | e2 e/>g/ | f2 f/>a/ | g2 B/>e/ | d e f |"_D.C." g2 :: 
[K:C]"^Trio." e/>d/ | (e2 g) | (c2 e) | A f f | f2 f/>e/ | (f2 a) | (f2 a) | B e d |"_D.C." c2 :|  