#------------------------------------------------------------------------------
#$Date: 2016-02-20 00:18:51 +0200 (Sat, 20 Feb 2016) $
#$Revision: 176760 $
#$URL: svn://www.crystallography.net/cod/cif/2/01/33/2013334.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided by IUCr Journals, http://journals.iucr.org/.
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_2013334
loop_
_publ_author_name
'Anwar Usman'
'Hoong-Kun Fun'
'Lei Wang'
'Yan Zhang'
'Jian-Hua Xu'
_publ_section_title
;1-Acetyl-4'-ethyl-2a'-phenyl-2',2a',5',5a'-tetrahydrospiro[1H-indole-3,2'-oxeto[5,4-b]oxazol]-2(3H)-one
 and
 1-acetyl-4',5a'-diphenyl-2',2a',5',5a'-tetrahydrospiro[1H-indole-3,2'-oxeto[5,4-b]oxazol]-2(3H)-one
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o305
_journal_page_last               o307
_journal_paper_doi               10.1107/S0108270103008680
_journal_volume                  59
_journal_year                    2003
_chemical_formula_iupac          'C21 H18 N2 O4'
_chemical_formula_moiety         'C21 H18 N2 O4'
_chemical_formula_sum            'C21 H18 N2 O4'
_chemical_formula_weight         362.37
_chemical_melting_point          392.0(10)
_chemical_name_systematic
;
1-Acetyl-2a'-phenyl-4'-ethylspiro[indole-3,2'-[2a'H,5a'H]oxeto[5,4-b]oxazol]-
2(1H)-one
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 97.3860(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.8569(6)
_cell_length_b                   12.4129(6)
_cell_length_c                   12.9849(6)
_cell_measurement_reflns_used    6010
_cell_measurement_temperature    213(2)
_cell_measurement_theta_max      28.30
_cell_measurement_theta_min      2.28
_cell_volume                     1735.40(15)
_computing_cell_refinement       'SAINT (Siemens, 1996)'
_computing_data_collection       'SMART (Siemens, 1996)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    SHELXTL
_computing_publication_material
;
SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 2003)
;
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 1997)'
_diffrn_ambient_temperature      213(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 0.983
_diffrn_measured_fraction_theta_max 0.983
_diffrn_measurement_device_type  'Siemens SMART CCD area-detector'
_diffrn_measurement_method       ω
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0149
_diffrn_reflns_av_sigmaI/netI    0.0179
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            10582
_diffrn_reflns_theta_full        28.29
_diffrn_reflns_theta_max         28.29
_diffrn_reflns_theta_min         2.28
_diffrn_standards_decay_%        negligible
_diffrn_standards_interval_count none
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.097
_exptl_absorpt_correction_T_max  0.9603
_exptl_absorpt_correction_T_min  0.8994
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.387
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             760
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.44
_exptl_crystal_size_min          0.42
_refine_diff_density_max         0.338
_refine_diff_density_min         -0.434
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.071
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     257
_refine_ls_number_reflns         4238
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.071
_refine_ls_R_factor_all          0.0622
_refine_ls_R_factor_gt           0.0491
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[σ²(Fo²)+(0.0644P)²+0.7497P] where P = (Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1276
_refine_ls_wR_factor_ref         0.1420
_reflns_number_gt                3439
_reflns_number_total             4238
_reflns_threshold_expression     I>2σ(I)
_cod_data_source_file            na1612.cif
_cod_data_source_block           I
_cod_original_cell_volume        1735.4(2)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2013334
_cod_database_fobs_code          2013334
loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-x+1/2, y+1/2, -z+1/2'
'-x, -y, -z'
'x-1/2, -y-1/2, z-1/2'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_calc_flag
_atom_site_refinement_flags
_atom_site_occupancy
_atom_site_disorder_assembly
_atom_site_disorder_group
_atom_site_type_symbol
O1 0.33060(10) 0.43585(10) 0.20936(8) 0.0392(3) Uani d . 1 . . O
O2 0.15416(12) 0.41369(11) 0.29910(9) 0.0475(3) Uani d . 1 . . O
O3 0.2776(2) 0.68099(15) -0.17305(12) 0.0822(6) Uani d . 1 . . O
O4 0.20403(12) 0.62977(9) 0.13021(9) 0.0416(3) Uani d . 1 . . O
N1 0.26945(12) 0.58189(10) -0.02832(10) 0.0335(3) Uani d . 1 . . N
N2 0.04952(12) 0.42914(11) 0.13637(10) 0.0367(3) Uani d . 1 . . N
C1 0.34922(14) 0.41368(13) 0.01835(12) 0.0344(3) Uani d . 1 . . C
C2 0.41497(15) 0.31978(14) 0.00799(16) 0.0457(4) Uani d . 1 . . C
H2 0.4246 0.2686 0.0607 0.055 Uiso calc R 1 . . H
C3 0.46650(17) 0.30404(18) -0.08403(19) 0.0567(6) Uani d . 1 . . C
H3 0.5117 0.2418 -0.0927 0.068 Uiso calc R 1 . . H
C4 0.45093(17) 0.38003(19) -0.16219(16) 0.0562(5) Uani d . 1 . . C
H4 0.4849 0.3673 -0.2232 0.067 Uiso calc R 1 . . H
C5 0.38621(17) 0.47455(18) -0.15234(14) 0.0493(4) Uani d . 1 . . C
H5 0.3767 0.5256 -0.2052 0.059 Uiso calc R 1 . . H
C6 0.33586(14) 0.49036(13) -0.06022(12) 0.0355(3) Uani d . 1 . . C
C7 0.24238(14) 0.56448(12) 0.07382(11) 0.0313(3) Uani d . 1 . . C
C8 0.27546(14) 0.44720(12) 0.10211(11) 0.0305(3) Uani d . 1 . . C
C9 0.23545(15) 0.36518(13) 0.23500(11) 0.0353(3) Uani d . 1 . . C
H9 0.2644 0.2930 0.2570 0.042 Uiso calc R 1 . . H
C10 0.05268(17) 0.44954(17) 0.23200(13) 0.0473(4) Uani d . 1 B . C
C11 0.16401(13) 0.37062(12) 0.12461(11) 0.0296(3) Uani d . 1 . . C
C12 0.14160(13) 0.27252(12) 0.05758(11) 0.0306(3) Uani d . 1 . . C
C13 0.16555(16) 0.16968(13) 0.09640(13) 0.0380(4) Uani d . 1 . . C
H13 0.1960 0.1600 0.1660 0.046 Uiso calc R 1 . . H
C14 0.1441(2) 0.08116(14) 0.03138(15) 0.0499(4) Uani d . 1 . . C
H14 0.1597 0.0121 0.0577 0.060 Uiso calc R 1 . . H
C15 0.0997(2) 0.09501(16) -0.07210(15) 0.0514(5) Uani d . 1 . . C
H15 0.0856 0.0353 -0.1153 0.062 Uiso calc R 1 . . H
C16 0.07611(18) 0.19712(16) -0.11167(13) 0.0459(4) Uani d . 1 . . C
H16 0.0469 0.2063 -0.1816 0.055 Uiso calc R 1 . . H
C17 0.09600(15) 0.28597(14) -0.04718(12) 0.0373(3) Uani d . 1 . . C
H17 0.0789 0.3547 -0.0737 0.045 Uiso calc R 1 . . H
C18 0.24998(17) 0.67809(15) -0.08627(14) 0.0444(4) Uani d . 1 . . C
C19 0.19732(18) 0.77318(15) -0.03783(16) 0.0490(4) Uani d . 1 . . C
H19A 0.1839 0.8303 -0.0879 0.073 Uiso calc R 1 . . H
H19B 0.2543 0.7969 0.0204 0.073 Uiso calc R 1 . . H
H19C 0.1198 0.7538 -0.0148 0.073 Uiso calc R 1 . . H
C20 -0.0427(3) 0.5096(3) 0.28200(18) 0.0933(11) Uani d . 1 . . C
H20A -0.1206 0.4969 0.2396 0.112 Uiso d PR 0.40 A 1 H
H20B -0.0243 0.5847 0.2750 0.112 Uiso d PR 0.40 A 1 H
H20C -0.0835 0.4599 0.3230 0.112 Uiso d PR 0.60 A 2 H
H20D -0.1041 0.5356 0.2278 0.112 Uiso d PR 0.60 A 2 H
C21A -0.0616(8) 0.4970(6) 0.3825(5) 0.087(2) Uani d P 0.40 B 1 C
H21A -0.1126 0.5548 0.4021 0.130 Uiso calc PR 0.40 B 1 H
H21B 0.0168 0.4979 0.4260 0.130 Uiso calc PR 0.40 B 1 H
H21C -0.1025 0.4295 0.3905 0.130 Uiso calc PR 0.40 B 1 H
C21B -0.0045(4) 0.5913(3) 0.3410(3) 0.0682(10) Uani d P 0.60 B 2 C
H21D -0.0740 0.6238 0.3677 0.102 Uiso calc PR 0.60 B 2 H
H21E 0.0343 0.6433 0.3009 0.102 Uiso calc PR 0.60 B 2 H
H21F 0.0544 0.5667 0.3976 0.102 Uiso calc PR 0.60 B 2 H
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'
loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_publ_flag
C9 O1 C8 93.60(10) ?
C10 O2 C9 105.70(10) ?
C7 N1 C18 126.50(10) ?
C7 N1 C6 108.80(10) ?
C18 N1 C6 124.20(10) ?
C10 N2 C11 106.60(10) ?
C2 C1 C6 120.8(2) ?
C2 C1 C8 129.7(2) ?
C6 C1 C8 109.20(10) ?
C1 C2 C3 118.0(2) ?
C1 C2 H2 121.0 ?
C3 C2 H2 121.0 ?
C4 C3 C2 120.6(2) ?
C4 C3 H3 119.7 ?
C2 C3 H3 119.7 ?
C3 C4 C5 121.9(2) ?
C3 C4 H4 119.1 ?
C5 C4 H4 119.1 ?
C4 C5 C6 117.4(2) ?
C4 C5 H5 121.3 ?
C6 C5 H5 121.3 ?
C1 C6 C5 121.3(2) ?
C1 C6 N1 109.80(10) ?
C5 C6 N1 128.9(2) ?
O4 C7 N1 126.80(10) ?
O4 C7 C8 125.70(10) ?
N1 C7 C8 107.50(10) ?
O1 C8 C1 118.70(10) ?
O1 C8 C7 112.20(10) ?
C1 C8 C7 102.80(10) ?
O1 C8 C11 89.70(10) ?
C1 C8 C11 117.30(10) ?
C7 C8 C11 116.70(10) ?
O2 C9 O1 113.50(10) yes
O2 C9 C11 104.50(10) ?
O1 C9 C11 92.80(10) ?
O2 C9 H9 114.6 ?
O1 C9 H9 114.6 ?
C11 C9 H9 114.6 ?
N2 C10 O2 118.2(2) ?
N2 C10 C20 126.6(2) ?
O2 C10 C20 115.3(2) ?
N2 C11 C12 112.80(10) yes
N2 C11 C9 104.90(10) ?
C12 C11 C9 122.00(10) ?
N2 C11 C8 113.40(10) yes
C12 C11 C8 116.60(10) yes
C9 C11 C8 83.90(10) ?
C13 C12 C17 119.40(10) ?
C13 C12 C11 121.90(10) ?
C17 C12 C11 118.70(10) ?
C12 C13 C14 120.00(10) ?
C12 C13 H13 120.0 ?
C14 C13 H13 120.0 ?
C15 C14 C13 120.3(2) ?
C15 C14 H14 119.8 ?
C13 C14 H14 119.8 ?
C14 C15 C16 120.2(2) ?
C14 C15 H15 119.9 ?
C16 C15 H15 119.9 ?
C15 C16 C17 120.0(2) ?
C15 C16 H16 120.0 ?
C17 C16 H16 120.0 ?
C16 C17 C12 120.1(2) ?
C16 C17 H17 119.9 ?
C12 C17 H17 119.9 ?
O3 C18 N1 119.1(2) ?
O3 C18 C19 121.9(2) ?
N1 C18 C19 119.0(2) ?
C18 C19 H19A 109.5 ?
C18 C19 H19B 109.5 ?
H19A C19 H19B 109.5 ?
C18 C19 H19C 109.5 ?
H19A C19 H19C 109.5 ?
H19B C19 H19C 109.5 ?
C21B C20 C21A 66.5(4) ?
C21B C20 C10 117.2(3) ?
C21A C20 C10 124.1(3) ?
C21B C20 H20A 130.8 ?
C21A C20 H20A 107.6 ?
C10 C20 H20A 106.2 ?
C21B C20 H20B 41.2 ?
C21A C20 H20B 105.2 ?
C10 C20 H20B 106.2 ?
H20A C20 H20B 106.5 ?
C21B C20 H20C 108.0 ?
C21A C20 H20C 41.8 ?
C10 C20 H20C 108.4 ?
H20A C20 H20C 77.2 ?
H20B C20 H20C 142.5 ?
C21B C20 H20D 107.9 ?
C21A C20 H20D 124.6 ?
C10 C20 H20D 107.7 ?
H20A C20 H20D 32.8 ?
H20B C20 H20D 74.8 ?
H20C C20 H20D 107.3 ?
C20 C21A H20C 45.0 ?
C20 C21A H21A 109.5 ?
H20C C21A H21A 120.7 ?
C20 C21A H21B 109.5 ?
H20C C21A H21B 128.6 ?
C20 C21A H21C 109.5 ?
H20C C21A H21C 64.7 ?
C20 C21B H20B 47.3 ?
C20 C21B H21D 109.5 ?
C20 C21B H21E 109.5 ?
H21D C21B H21E 109.5 ?
C20 C21B H21F 109.5 ?
H21D C21B H21F 109.5 ?
H21E C21B H21F 109.5 ?
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_site_symmetry_2
_geom_bond_distance
_geom_bond_publ_flag
O1 C9 . 1.427(2) yes
O1 C8 . 1.450(2) ?
O2 C10 . 1.387(2) ?
O2 C9 . 1.422(2) yes
O3 C18 . 1.203(2) ?
O4 C7 . 1.202(2) ?
N1 C7 . 1.412(2) ?
N1 C18 . 1.413(2) ?
N1 C6 . 1.435(2) ?
N2 C10 . 1.263(2) yes
N2 C11 . 1.465(2) yes
C1 C2 . 1.382(2) ?
C1 C6 . 1.389(2) ?
C1 C8 . 1.490(2) ?
C2 C3 . 1.397(3) ?
C2 H2 . 0.9300 ?
C3 C4 . 1.380(3) ?
C3 H3 . 0.9300 ?
C4 C5 . 1.382(3) ?
C4 H4 . 0.9300 ?
C5 C6 . 1.391(2) ?
C5 H5 . 0.9300 ?
C7 C8 . 1.533(2) ?
C8 C11 . 1.595(2) yes
C9 C11 . 1.541(2) yes
C9 H9 . 0.9800 ?
C10 C20 . 1.491(3) yes
C11 C12 . 1.498(2) yes
C12 C13 . 1.385(2) ?
C12 C17 . 1.396(2) ?
C13 C14 . 1.387(2) ?
C13 H13 . 0.9300 ?
C14 C15 . 1.379(3) ?
C14 H14 . 0.9300 ?
C15 C16 . 1.379(3) ?
C15 H15 . 0.9300 ?
C16 C17 . 1.385(2) ?
C16 H16 . 0.9300 ?
C17 H17 . 0.9300 ?
C18 C19 . 1.486(3) ?
C19 H19A . 0.9600 ?
C19 H19B . 0.9600 ?
C19 H19C . 0.9600 ?
C20 C21B . 1.306(5) yes
C20 C21A . 1.355(5) yes
C20 H20A . 0.9602 ?
C20 H20B . 0.9601 ?
C20 H20C . 0.9600 ?
C20 H20D . 0.9602 ?
C21A H20C . 0.9045 ?
C21A H21A . 0.9600 ?
C21A H21B . 0.9600 ?
C21A H21C . 0.9600 ?
C21B H20B . 0.8602 ?
C21B H21D . 0.9600 ?
C21B H21E . 0.9600 ?
C21B H21F . 0.9600 ?
loop_
_geom_hbond_atom_site_label_D
_geom_hbond_atom_site_label_H
_geom_hbond_atom_site_label_A
_geom_hbond_site_symmetry_A
_geom_hbond_distance_DH
_geom_hbond_distance_HA
_geom_hbond_distance_DA
_geom_hbond_angle_DHA
_geom_hbond_publ_flag
C5 H5 O3 1_555 0.93 2.27 2.819(3) 117 yes
loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_publ_flag
C6 C1 C2 C3 -0.5(2) ?
C8 C1 C2 C3 173.8(2) ?
C1 C2 C3 C4 -0.5(3) ?
C2 C3 C4 C5 1.0(3) ?
C3 C4 C5 C6 -0.5(3) ?
C2 C1 C6 C5 1.1(2) ?
C8 C1 C6 C5 -174.30(10) ?
C2 C1 C6 N1 -177.20(10) ?
C8 C1 C6 N1 7.5(2) ?
C4 C5 C6 C1 -0.6(2) ?
C4 C5 C6 N1 177.3(2) ?
C7 N1 C6 C1 1.4(2) ?
C18 N1 C6 C1 174.00(10) ?
C7 N1 C6 C5 -176.6(2) ?
C18 N1 C6 C5 -4.0(3) ?
C18 N1 C7 O4 -3.9(3) ?
C6 N1 C7 O4 168.5(2) ?
C18 N1 C7 C8 178.20(10) ?
C6 N1 C7 C8 -9.4(2) ?
C9 O1 C8 C1 -120.30(10) ?
C9 O1 C8 C7 120.00(10) ?
C9 O1 C8 C11 1.00(10) ?
C2 C1 C8 O1 48.3(2) ?
C6 C1 C8 O1 -136.90(10) ?
C2 C1 C8 C7 172.7(2) ?
C6 C1 C8 C7 -12.5(2) ?
C2 C1 C8 C11 -57.8(2) ?
C6 C1 C8 C11 117.10(10) ?
O4 C7 C8 O1 -36.2(2) ?
N1 C7 C8 O1 141.80(10) ?
O4 C7 C8 C1 -164.8(2) ?
N1 C7 C8 C1 13.2(2) ?
O4 C7 C8 C11 65.4(2) ?
N1 C7 C8 C11 -116.70(10) ?
C10 O2 C9 O1 95.8(2) ?
C10 O2 C9 C11 -3.9(2) ?
C8 O1 C9 O2 -108.20(10) ?
C8 O1 C9 C11 -1.10(10) ?
C11 N2 C10 O2 -0.9(2) ?
C11 N2 C10 C20 178.9(3) ?
C9 O2 C10 N2 3.3(2) ?
C9 O2 C10 C20 -176.6(2) ?
C10 N2 C11 C12 133.2(2) ?
C10 N2 C11 C9 -1.7(2) ?
C10 N2 C11 C8 -91.4(2) ?
O2 C9 C11 N2 3.5(2) yes
O1 C9 C11 N2 -111.70(10) ?
O2 C9 C11 C12 -126.20(10) ?
O1 C9 C11 C12 118.70(10) ?
O2 C9 C11 C8 116.10(10) ?
O1 C9 C11 C8 1.00(10) yes
O1 C8 C11 N2 102.70(10) ?
C1 C8 C11 N2 -134.90(10) ?
C7 C8 C11 N2 -12.2(2) ?
O1 C8 C11 C12 -123.80(10) ?
C1 C8 C11 C12 -1.3(2) yes
C7 C8 C11 C12 121.40(10) ?
O1 C8 C11 C9 -1.00(10) ?
C1 C8 C11 C9 121.50(10) ?
C7 C8 C11 C9 -115.80(10) ?
N2 C11 C12 C13 -115.5(2) ?
C9 C11 C12 C13 10.7(2) ?
C8 C11 C12 C13 110.7(2) ?
N2 C11 C12 C17 65.0(2) ?
C9 C11 C12 C17 -168.80(10) ?
C8 C11 C12 C17 -68.9(2) ?
C17 C12 C13 C14 -0.1(2) ?
C11 C12 C13 C14 -179.6(2) ?
C12 C13 C14 C15 0.4(3) ?
C13 C14 C15 C16 -0.1(3) ?
C14 C15 C16 C17 -0.6(3) ?
C15 C16 C17 C12 0.9(3) ?
C13 C12 C17 C16 -0.6(2) ?
C11 C12 C17 C16 179.0(2) ?
C7 N1 C18 O3 -179.9(2) ?
C6 N1 C18 O3 8.8(3) ?
C7 N1 C18 C19 0.8(3) ?
C6 N1 C18 C19 -170.5(2) ?
N2 C10 C20 C21B -126.6(3) ?
O2 C10 C20 C21B 53.2(4) ?
N2 C10 C20 C21A 154.6(6) ?
O2 C10 C20 C21A -25.6(7) ?
