P PA(S) O O1A O H O2A O O5B C5B C4B(R) O O4B C3B(R) O H O3B C2B(R) O O2B C1B(R) N N9A C8A N N7A C5A C6A N H 2 N6A N N1A C2A N N3A C4A O O3 P PN(S) O O1N O H O2N O O5D C5D C4D(R) O O4D C3D(S) O H O3D C2D(R) O H O2D C1D(R) N N1N C2N C3N C7N O O7N N H 2 N7N C4N C5N C6N P P2B O O1X O H O2X O H O3X