O
O7N
C7N
N
H
2
N7N
C3N
C4N
C5N
C6N
C2N
N
+
N1N
C1'(R)
C2'(R)
O
H
O2'
C3'(S)
O
H
O3'
O
O4'
C4'(R)
C5'
O
O5'
P
PN(R)
O
H
O1N
O
O2N
O
OPP
P
PA(S)
O
H
O1A
O
O2A
O
O5B
C5B
C4B(R)
O
O4B
C1B(R)
C2B(R)
O
H
O2B
C3B(S)
O
H
O3B
N
N9A
C8A
I
I8A
N
N7A
C5A
C6A
N
H
2
N6A
C4A
N
N3A
C2A
N
N1A