# Copyright The Royal Society of Chemistry, 1999 # CCDC Number: 207/334 data_s _audit_creation_method SHELXL-97 _chemical_name_systematic ; ? ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_sum 'C12 H11 N5 O' _chemical_formula_weight 241.26 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'N' 'N' 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'O' 'O' 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting 'tetragonal' _symmetry_space_group_name_H-M 'P -4 21 c No 114' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, -y, z' 'x+1/2, -y+1/2, -z+1/2' '-x+1/2, y+1/2, -z+1/2' 'y+1/2, x+1/2, z+1/2' '-y+1/2, -x+1/2, z+1/2' '-y, x, -z' 'y, -x, -z' _cell_length_a 19.028(4) _cell_length_b 19.028(4) _cell_length_c 7.014(3) _cell_angle_alpha 90.00 _cell_angle_beta 90.00 _cell_angle_gamma 90.00 _cell_volume 2539.6(13) _cell_formula_units_Z 8 _cell_measurement_temperature 293(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min ? _cell_measurement_theta_max ? _exptl_crystal_description 'needle' _exptl_crystal_colour 'red' _exptl_crystal_size_max 0.40 _exptl_crystal_size_mid 0.15 _exptl_crystal_size_min 0.15 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.262 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 1008 _exptl_absorpt_coefficient_mu 0.087 _exptl_absorpt_correction_type ? _exptl_absorpt_correction_T_min 0.9661 _exptl_absorpt_correction_T_max 0.9871 _exptl_special_details ; ? ; _diffrn_ambient_temperature 293(2) _diffrn_radiation_wavelength 0.71069 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type ? _diffrn_measurement_method ? _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 1291 _diffrn_reflns_av_R_equivalents 0.0000 _diffrn_reflns_av_sigmaI/netI 0.1304 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 22 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 16 _diffrn_reflns_limit_l_min 0 _diffrn_reflns_limit_l_max 8 _diffrn_reflns_theta_min 1.51 _diffrn_reflns_theta_max 25.00 _reflns_number_total 1291 _reflns_number_gt 487 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0810P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881' _refine_ls_abs_structure_Flack -4(7) _refine_ls_number_reflns 1291 _refine_ls_number_parameters 175 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.2003 _refine_ls_R_factor_gt 0.0468 _refine_ls_wR_factor_ref 0.1869 _refine_ls_wR_factor_gt 0.1282 _refine_ls_goodness_of_fit_ref 1.007 _refine_ls_restrained_S_all 1.007 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.2002(2) 0.1606(3) 0.3644(7) 0.0562(15) Uani 1 d . . . N1 N 0.2379(3) 0.1995(4) 0.2213(9) 0.0539(17) Uani 1 d . . . N2 N 0.1284(3) 0.2535(3) 0.1953(9) 0.0492(17) Uani 1 d . . . N3 N 0.0869(4) 0.2842(4) -0.2814(11) 0.077(3) Uani 1 d . . . N4 N -0.0477(4) 0.4124(4) -0.0411(12) 0.094(3) Uani 1 d . . . N5 N 0.0335(5) 0.3529(4) 0.3575(12) 0.059(2) Uani 1 d . . . C1 C 0.0831(4) 0.2959(4) 0.0820(10) 0.046(2) Uani 1 d . . . C2 C 0.0392(4) 0.3405(4) 0.1680(11) 0.048(2) Uani 1 d . . . C3 C 0.2029(4) 0.0726(4) 0.6002(13) 0.055(2) Uani 1 d . . . C4 C 0.2064(5) 0.0962(5) 0.7841(14) 0.068(3) Uani 1 d . . . H4 H 0.2358 0.1334 0.8161 0.082 Uiso 1 calc R . . C5 C 0.1656(5) 0.0640(5) 0.9216(14) 0.088(3) Uani 1 d . . . H5 H 0.1671 0.0803 1.0465 0.105 Uiso 1 calc R . . C6 C 0.1238(6) 0.0094(6) 0.8778(19) 0.088(4) Uani 1 d . . . H6 H 0.0965 -0.0118 0.9716 0.105 Uiso 1 calc R . . C7 C 0.1217(5) -0.0144(6) 0.699(2) 0.086(4) Uani 1 d . . . H7 H 0.0936 -0.0528 0.6691 0.103 Uiso 1 calc R . . C8 C 0.1601(5) 0.0170(4) 0.5582(16) 0.076(3) Uani 1 d . . . H8 H 0.1571 0.0005 0.4336 0.091 Uiso 1 calc R . . C9 C 0.2444(5) 0.1102(5) 0.4493(14) 0.075(3) Uani 1 d . . . H9A H 0.2850 0.1330 0.5056 0.090 Uiso 1 calc R . . H9B H 0.2607 0.0770 0.3540 0.090 Uiso 1 calc R . . C10 C 0.1974(4) 0.2421(4) 0.1433(10) 0.049(2) Uani 1 d . . . H10 H 0.2150 0.2683 0.0421 0.058 Uiso 1 calc R . . C11 C 0.0836(4) 0.2887(4) -0.1193(13) 0.057(2) Uani 1 d . . . C12 C -0.0104(5) 0.3800(5) 0.0495(13) 0.066(3) Uani 1 d . . . H2 H 0.094(4) 0.213(4) 0.284(11) 0.07(2) Uiso 1 d . . . H5B H 0.001(6) 0.359(6) 0.388(16) 0.11(6) Uiso 1 d . . . H5A H 0.072(3) 0.318(3) 0.459(8) 0.039(19) Uiso 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.049(3) 0.062(4) 0.057(3) 0.016(3) 0.006(3) 0.009(3) N1 0.050(4) 0.057(4) 0.055(4) 0.008(4) -0.001(4) 0.013(3) N2 0.055(4) 0.042(4) 0.051(4) 0.001(4) -0.002(4) 0.006(3) N3 0.068(5) 0.105(7) 0.058(5) -0.006(5) -0.004(5) 0.008(5) N4 0.073(6) 0.113(7) 0.095(6) 0.028(6) -0.013(5) 0.036(5) N5 0.060(6) 0.058(5) 0.057(5) 0.001(4) 0.012(5) 0.010(4) C1 0.040(4) 0.053(5) 0.047(5) 0.011(5) -0.002(4) 0.006(4) C2 0.052(5) 0.044(5) 0.047(5) 0.015(5) -0.005(5) -0.007(4) C3 0.056(5) 0.052(6) 0.058(6) 0.003(5) 0.000(5) 0.021(5) C4 0.079(6) 0.056(6) 0.071(6) -0.004(5) 0.008(6) -0.009(6) C5 0.110(8) 0.094(8) 0.059(7) 0.000(6) 0.013(7) 0.003(7) C6 0.088(8) 0.049(6) 0.126(11) 0.007(7) 0.010(9) -0.010(6) C7 0.065(7) 0.050(6) 0.142(12) -0.011(8) -0.014(9) 0.006(5) C8 0.106(9) 0.031(5) 0.090(8) -0.003(5) -0.028(8) 0.013(6) C9 0.087(7) 0.066(6) 0.070(6) 0.006(6) 0.007(6) 0.040(5) C10 0.058(5) 0.047(5) 0.040(4) 0.010(4) 0.006(4) 0.007(4) C11 0.051(5) 0.064(6) 0.056(6) 0.002(5) -0.001(5) 0.001(4) C12 0.058(6) 0.076(7) 0.065(6) 0.015(6) -0.015(5) 0.008(5) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C9 1.408(9) . ? O1 N1 1.440(8) . ? N1 C10 1.245(8) . ? N2 C10 1.379(9) . ? N2 C1 1.423(9) . ? N3 C11 1.142(9) . ? N4 C12 1.134(10) . ? N5 C2 1.355(11) . ? C1 C2 1.335(10) . ? C1 C11 1.418(12) . ? C2 C12 1.465(12) . ? C3 C4 1.367(11) . ? C3 C8 1.368(11) . ? C3 C9 1.502(13) . ? C4 C5 1.382(12) . ? C5 C6 1.344(14) . ? C6 C7 1.336(14) . ? C7 C8 1.363(14) . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C9 O1 N1 110.3(6) . . ? C10 N1 O1 109.4(6) . . ? C10 N2 C1 121.2(7) . . ? C2 C1 C11 121.0(7) . . ? C2 C1 N2 119.1(6) . . ? C11 C1 N2 119.8(7) . . ? C1 C2 N5 127.1(8) . . ? C1 C2 C12 118.2(7) . . ? N5 C2 C12 114.6(8) . . ? C4 C3 C8 119.1(9) . . ? C4 C3 C9 118.9(8) . . ? C8 C3 C9 122.0(9) . . ? C3 C4 C5 119.0(9) . . ? C6 C5 C4 121.1(10) . . ? C7 C6 C5 119.6(11) . . ? C6 C7 C8 121.0(10) . . ? C7 C8 C3 120.2(10) . . ? O1 C9 C3 108.0(7) . . ? N1 C10 N2 125.1(7) . . ? N3 C11 C1 177.0(10) . . ? N4 C12 C2 178.0(11) . . ? _diffrn_measured_fraction_theta_max 0.995 _diffrn_reflns_theta_full 25.00 _diffrn_measured_fraction_theta_full 0.995 _refine_diff_density_max 0.180 _refine_diff_density_min -0.218 _refine_diff_density_rms 0.048 data_bo97 _audit_creation_method SHELXL-97 _chemical_name_systematic ; ? ; _chemical_name_common ? _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C12 H11 N5 O' _chemical_formula_weight 241.26 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'N' 'N' 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'O' 'O' 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting 'monoclinic' _symmetry_space_group_name_H-M 'P 2(1)' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z' _cell_length_a 8.3838(10) _cell_length_b 6.6380(10) _cell_length_c 10.580(2) _cell_angle_alpha 90.00 _cell_angle_beta 93.35(2) _cell_angle_gamma 90.00 _cell_volume 587.79(16) _cell_formula_units_Z 2 _cell_measurement_temperature 293(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min ? _cell_measurement_theta_max ? _exptl_crystal_description 'block' _exptl_crystal_colour 'orange' _exptl_crystal_size_max 0.35 _exptl_crystal_size_mid 0.25 _exptl_crystal_size_min 0.20 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.363 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 252 _exptl_absorpt_coefficient_mu 0.094 _exptl_absorpt_correction_type ? _exptl_absorpt_correction_T_min 0.9679 _exptl_absorpt_correction_T_max 0.9815 _exptl_absorpt_process_details ? _exptl_special_details ; ? ; _diffrn_ambient_temperature 293(2) _diffrn_radiation_wavelength 0.71069 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type ? _diffrn_measurement_method ? _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 2162 _diffrn_reflns_av_R_equivalents 0.0190 _diffrn_reflns_av_sigmaI/netI 0.0212 _diffrn_reflns_limit_h_min -7 _diffrn_reflns_limit_h_max 9 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 7 _diffrn_reflns_limit_l_min -12 _diffrn_reflns_limit_l_max 12 _diffrn_reflns_theta_min 1.93 _diffrn_reflns_theta_max 24.97 _reflns_number_total 1132 _reflns_number_gt 963 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881' _refine_ls_abs_structure_Flack -1(2) _refine_ls_number_reflns 1132 _refine_ls_number_parameters 179 _refine_ls_number_restraints 1 _refine_ls_R_factor_all 0.0434 _refine_ls_R_factor_gt 0.0343 _refine_ls_wR_factor_ref 0.1151 _refine_ls_wR_factor_gt 0.1057 _refine_ls_goodness_of_fit_ref 0.964 _refine_ls_restrained_S_all 0.963 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group N1 N 1.0957(2) 0.1886(3) 0.72301(18) 0.0395(5) Uani 1 1 d . . . C2 C 1.0294(3) 0.3662(4) 0.6845(3) 0.0476(7) Uani 1 1 d . . . N3 N 0.8977(3) 0.3789(3) 0.6179(3) 0.0471(6) Uani 1 1 d . . . C4 C 0.8218(3) 0.1989(4) 0.5876(2) 0.0384(5) Uani 1 1 d . . . C5 C 0.8763(3) 0.0119(4) 0.6260(2) 0.0359(5) Uani 1 1 d . . . C6 C 1.0295(3) 0.0009(4) 0.7007(2) 0.0371(5) Uani 1 1 d . . . O7 O 1.23544(17) 0.1959(3) 0.80017(13) 0.0426(4) Uani 1 1 d . . . C8 C 1.3721(3) 0.2060(6) 0.7221(2) 0.0512(6) Uani 1 1 d . . . H8A H 1.3697 0.3304 0.6739 0.061 Uiso 1 1 calc R . . H8B H 1.3701 0.0939 0.6632 0.061 Uiso 1 1 calc R . . C9 C 1.5192(3) 0.1972(6) 0.8079(2) 0.0495(6) Uani 1 1 d . . . C10 C 1.6061(4) 0.3675(7) 0.8366(4) 0.0760(11) Uani 1 1 d . . . H10 H 1.5727 0.4917 0.8041 0.091 Uiso 1 1 calc R . . C11 C 1.7455(5) 0.3526(11) 0.9153(5) 0.111(2) Uani 1 1 d . . . H11 H 1.8037 0.4680 0.9371 0.133 Uiso 1 1 calc R . . C12 C 1.7962(5) 0.1716(14) 0.9599(3) 0.117(2) Uani 1 1 d . . . H12 H 1.8912 0.1621 1.0094 0.140 Uiso 1 1 calc R . . C13 C 1.7083(5) 0.0030(12) 0.9324(4) 0.111(2) Uani 1 1 d . . . H13 H 1.7419 -0.1210 0.9650 0.133 Uiso 1 1 calc R . . C15 C 0.6761(3) 0.2138(4) 0.5117(2) 0.0443(6) Uani 1 1 d . . . C14 C 1.5716(4) 0.0162(8) 0.8574(3) 0.0759(11) Uani 1 1 d . . . H14 H 1.5124 -0.0998 0.8391 0.091 Uiso 1 1 calc R . . N16 N 0.5594(3) 0.2210(5) 0.4509(2) 0.0621(7) Uani 1 1 d . . . N17 N 0.8016(3) -0.1627(4) 0.6019(2) 0.0476(6) Uani 1 1 d . . . N18 N 1.0873(3) -0.1672(4) 0.7387(2) 0.0510(6) Uani 1 1 d . . . H2 H 1.087(4) 0.481(6) 0.710(3) 0.053(8) Uiso 1 1 d . . . H17A H 0.693(4) -0.169(7) 0.577(3) 0.061(8) Uiso 1 1 d . . . H17B H 0.853(4) -0.282(6) 0.628(3) 0.055(8) Uiso 1 1 d . . . H18 H 1.183(4) -0.150(6) 0.787(3) 0.056(8) Uiso 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 N1 0.0366(10) 0.0313(10) 0.0499(10) -0.0044(10) -0.0048(7) -0.0039(10) C2 0.0460(15) 0.0326(14) 0.0639(18) -0.0013(12) 0.0004(12) -0.0016(12) N3 0.0459(13) 0.0286(12) 0.0662(15) 0.0025(10) -0.0003(11) 0.0013(9) C4 0.0354(11) 0.0336(11) 0.0459(11) 0.0021(12) 0.0007(9) 0.0028(11) C5 0.0337(11) 0.0332(12) 0.0405(11) -0.0048(11) -0.0007(9) -0.0012(11) C6 0.0388(12) 0.0305(11) 0.0415(12) -0.0026(11) -0.0030(9) 0.0015(11) O7 0.0377(8) 0.0452(9) 0.0438(8) -0.0050(9) -0.0067(6) -0.0056(9) C8 0.0444(12) 0.0617(16) 0.0469(11) 0.0027(15) -0.0030(9) -0.0034(14) C9 0.0412(12) 0.0642(16) 0.0430(11) -0.0032(15) 0.0014(9) -0.0002(14) C10 0.0560(18) 0.080(3) 0.091(2) -0.031(2) -0.0024(16) -0.0074(18) C11 0.053(2) 0.159(5) 0.119(3) -0.082(4) -0.009(2) -0.015(3) C12 0.051(2) 0.240(8) 0.0576(18) -0.027(4) -0.0120(14) 0.037(4) C13 0.072(2) 0.182(6) 0.077(2) 0.046(3) -0.006(2) 0.039(4) C15 0.0419(13) 0.0354(13) 0.0555(12) 0.0050(12) 0.0019(10) 0.0041(12) C14 0.0643(19) 0.084(3) 0.079(2) 0.025(2) 0.0025(15) 0.0077(19) N16 0.0451(12) 0.0654(16) 0.0738(14) 0.0111(14) -0.0121(10) 0.0066(12) N17 0.0403(12) 0.0348(11) 0.0654(13) -0.0003(11) -0.0155(9) -0.0002(10) N18 0.0489(12) 0.0343(11) 0.0670(13) 0.0029(11) -0.0205(10) -0.0004(11) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag N1 C2 1.355(4) . ? N1 C6 1.379(3) . ? N1 O7 1.389(2) . ? C2 N3 1.277(4) . ? N3 C4 1.383(4) . ? C4 C5 1.376(4) . ? C4 C15 1.426(3) . ? C5 N17 1.335(4) . ? C5 C6 1.469(3) . ? C6 N18 1.273(4) . ? O7 C8 1.453(3) . ? C8 C9 1.489(3) . ? C9 C10 1.369(5) . ? C9 C14 1.373(6) . ? C10 C11 1.399(6) . ? C11 C12 1.350(10) . ? C12 C13 1.362(10) . ? C13 C14 1.358(6) . ? C15 N16 1.139(3) . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C2 N1 C6 125.49(18) . . ? C2 N1 O7 117.6(2) . . ? C6 N1 O7 116.7(2) . . ? N3 C2 N1 123.3(2) . . ? C2 N3 C4 116.3(2) . . ? C5 C4 N3 124.77(18) . . ? C5 C4 C15 119.2(3) . . ? N3 C4 C15 116.0(3) . . ? N17 C5 C4 125.6(2) . . ? N17 C5 C6 116.4(2) . . ? C4 C5 C6 117.9(2) . . ? N18 C6 N1 126.6(2) . . ? N18 C6 C5 121.2(2) . . ? N1 C6 C5 112.2(2) . . ? N1 O7 C8 109.50(15) . . ? O7 C8 C9 107.72(17) . . ? C10 C9 C14 119.0(3) . . ? C10 C9 C8 120.9(4) . . ? C14 C9 C8 120.1(3) . . ? C9 C10 C11 119.3(5) . . ? C12 C11 C10 120.4(5) . . ? C11 C12 C13 120.1(3) . . ? C14 C13 C12 120.0(6) . . ? N16 C15 C4 178.4(3) . . ? C13 C14 C9 121.3(5) . . ? _diffrn_measured_fraction_theta_max 0.999 _diffrn_reflns_theta_full 24.97 _diffrn_measured_fraction_theta_full 0.999 _refine_diff_density_max 0.147 _refine_diff_density_min -0.161 _refine_diff_density_rms 0.034