O
OAC
CBC
N
H
NAT
CBA
N
H
2
NAA
N
NAS
CBG
CBE
N
NAR
CAL
N
NBQ
CBO(R)
O
OAX
CBK(R)
CAN
O
OP3
P
P2'
O
O2'
O
H
OP2
O
OP1
CBI(R)
O
H
OAE
CBM(R)
O
OAZ
P
PBS
O
H
OAH
O
OAI
O
O5'
C5'
C4'(R)
O
O4'
C3'(R)
O
H
O3'
C2'(R)
C1'(R)
N
N9
C8
N
N7
C5
C4
N
N3
C2
N
N1
C6
N
H
2
N6
H
H6
H
H12
H
H16
H
H19