Oxetanyl Amino Acids for Peptidomimetics.
Möller, Guido P; Müller, Steffen; Wolfstädter, Bernd T; Wolfrum, Susanne; Schepmann, Dirk; Wünsch, Bernhard; Carreira, Erick M.; Organic letters 19 (2017) 2510–2513; doi:10.1021/acs.orglett.7b00745

data_1546213
_publ_section_title
;
 Oxetanyl Amino Acids for Peptidomimetics.
;
_journal_issue                   10
_journal_name_full               'Organic letters'
_journal_page_first              2510
_journal_page_last               2513
_journal_paper_doi               10.1021/acs.orglett.7b00745
_journal_volume                  19
_journal_year                    2017
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C25 H29 Br N2 O6'
_chemical_formula_sum            'C25 H29 Br N2 O6'
_chemical_formula_weight         533.41
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2013-06-05
_audit_creation_method
;
  Olex2 1.2
  (compiled Apr  9 2013 14:10:59, GUI svn.r4458)
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.0435(12)
_cell_length_b                   10.7709(14)
_cell_length_c                   24.399(3)
_cell_measurement_reflns_used    2861
_cell_measurement_temperature    100
_cell_measurement_theta_max      24.07
_cell_measurement_theta_min      2.63
_cell_volume                     2639.4(6)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics
;
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann,
OLEX2: a complete structure solution, refinement and analysis program.
J. Appl. Cryst. (2009). 42, 339-341.
;
_computing_publication_material
;
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann,
OLEX2: a complete structure solution, refinement and analysis program.
J. Appl. Cryst. (2009). 42, 339-341.
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      99.99
_diffrn_detector                 'Bruker APEX2 area detector'
_diffrn_detector_area_resol_mean 8.33
_diffrn_detector_type            'CCD area detector'
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       'kappa-stage diffractometer'
_diffrn_measurement_device_type  'Bruker Kappa Apex2 Duo'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  'focusing graphite'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_xray_symbol    K-L~3~
_diffrn_reflns_av_R_equivalents  0.0749
_diffrn_reflns_av_unetI/netI     0.1032
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            19149
_diffrn_reflns_theta_full        27.56
_diffrn_reflns_theta_max         27.56
_diffrn_reflns_theta_min         2.07
_diffrn_source                   'sealed tube'
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    1.597
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6584
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.0639 before and 0.0544 after correction.
The Ratio of minimum to maximum transmission is 0.8830.
The \l/2 correction factor is 0.0000.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.342
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1104
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.015
_refine_diff_density_max         0.574
_refine_diff_density_min         -0.401
_refine_diff_density_rms         0.068
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.013(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.951
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     341
_refine_ls_number_reflns         6080
_refine_ls_number_restraints     168
_refine_ls_restrained_S_all      0.945
_refine_ls_R_factor_all          0.0896
_refine_ls_R_factor_gt           0.0476
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0264P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0825
_refine_ls_wR_factor_ref         0.0930
_reflns_number_gt                4081
_reflns_number_total             6080
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol7b00745_si_007.cif
_cod_data_source_block           mo_ca300513_0m
_cod_database_code               1546213
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Rigid bond restraints
 C7A, C8A, C9A, C10A, C7B, C8B, C9B, C10B
 with sigma for 1-2 distances of 0.01 and sigma for 1-3 distances of 0.01
 O1, O2, O3, O4, O5, O21A, O21B
 with sigma for 1-2 distances of 0.01 and sigma for 1-3 distances of 0.01
3. Uiso/Uaniso restraints and constraints
C7A \\sim C8A \\sim C9A \\sim C10A \\sim C7B \\sim C8B \\sim C9B \\sim C10B: within 1.7A with sigma of 0.04 and sigma for terminal atoms of 0.08
O1 \\sim O2 \\sim O3 \\sim O4 \\sim O5 \\sim O21A \\sim O21B: within 1.7A with sigma of 0.04 and sigma for terminal atoms of 0.08
Uanis(C7A) \\sim Ueq, Uanis(C8A) \\sim Ueq, Uanis(C9A) \\sim Ueq, Uanis(C10A) \\sim Ueq, Uanis(C7B) \\sim Ueq, Uanis(C8B) \\sim Ueq, Uanis(C9B) \\sim Ueq, Uanis(C10B) \\sim Ueq: with sigma of 0.01 and sigma for terminal atoms of 0.02
Uanis(O21A) \\sim Ueq, Uanis(O21B) \\sim Ueq: with sigma of 0.01 and sigma for terminal atoms of 0.02
Uanis(C9B) = Uanis(C9A)
Uanis(C8A) = Uanis(C8B)
Uanis(O21A) = Uanis(O21B)
4. Same fragment restrains
{O21B, C7B, C8B, C9B, C10B}
as
{O21A, C7A, C8A, C9A, C10A}
5. Others
 1*Sof(O21A)=1*Sof(C7A)=1*Sof(C8A)=1*Sof(H8AA)=1*Sof(H8AB)=1*Sof(H8AC)=1*
 Sof(C9A)=1*Sof(H9AA)=1*Sof(H9AB)=1*Sof(H9AC)=1*Sof(C10A)=1*Sof(H10C)=1*
 Sof(H10D)=1*Sof(H10E)=1-1*Sof(O21B)=1-1*Sof(C7B)=1-1*Sof(C8B)=1-1*Sof(H8BA)=1-
 1*Sof(H8BB)=1-1*Sof(H8BC)=1-1*Sof(C9B)=1-1*Sof(H9BA)=1-1*Sof(H9BB)=1-1*
 Sof(H9BC)=1-1*Sof(C10B)=1-1*Sof(H10F)=1-1*Sof(H10G)=1-1*Sof(H10H)
6.a Ternary CH refined with riding coordinates:
 C7(H7)
6.b Secondary CH2 refined with riding coordinates:
 C10(H10A,H10B), C15(H15A,H15B), C16(H16A,H16B), C17(H17A,H17B)
6.c Aromatic/amide H refined with riding coordinates:
 N1(H1), C2(H2), C3(H3), N8(H8), C12(H12), C13(H13), C14(H14), C22(H22),
 C23(H23), C24(H24), C25(H25)
6.d Idealised Me refined as rotating group:
 C8A(H8AA,H8AB,H8AC), C9A(H9AA,H9AB,H9AC), C10A(H10C,H10D,H10E), C8B(H8BA,H8BB,
 H8BC), C9B(H9BA,H9BB,H9BC), C10B(H10F,H10G,H10H)
;