Boc-Val-Val-OMe (Aβ39–40) and Boc-Ile-Ala-OMe (Aβ41–42) crystallize in a parallel β-sheet arrangement but generate a different morphology
Giri, Rajat Subhra; Mandal, Bhubaneswar; CrystEngComm 20 (2018) 4441–; doi:10.1039/C8CE00097B

data_7231043
_publ_section_title
;
 Boc-Val-Val-OMe (A\b39--40) and Boc-Ile-Ala-OMe (A\b41--42) crystallize
 in a parallel \b-sheet arrangement but generate a different morphology
;
_journal_issue                   31
_journal_name_full               CrystEngComm
_journal_page_first              4441
_journal_paper_doi               10.1039/C8CE00097B
_journal_volume                  20
_journal_year                    2018
_chemical_formula_moiety         'C16 H30 N2 O5'
_chemical_formula_sum            'C16 H30 N2 O5'
_chemical_formula_weight         330.42
_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
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2018-06-27 deposited with the CCDC.
2018-06-28 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            12
_cell_length_a                   11.7141(3)
_cell_length_b                   18.6463(5)
_cell_length_c                   27.0913(7)
_cell_measurement_reflns_used    4146
_cell_measurement_temperature    150.00(10)
_cell_measurement_theta_max      27.6420
_cell_measurement_theta_min      1.8500
_cell_volume                     5917.4(3)
_computing_cell_refinement       'CrysAlisPro 1.171.38.46 (Rigaku OD, 2015)'
_computing_data_collection       'CrysAlisPro 1.171.38.46 (Rigaku OD, 2015)'
_computing_data_reduction        'CrysAlisPro 1.171.38.46 (Rigaku OD, 2015)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      150.00(10)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.882
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Eos'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0241
_diffrn_reflns_av_unetI/netI     0.0618
_diffrn_reflns_Laue_measured_fraction_full 0.991
_diffrn_reflns_Laue_measured_fraction_max 0.882
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            13225
_diffrn_reflns_point_group_measured_fraction_full 0.881
_diffrn_reflns_point_group_measured_fraction_max 0.750
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.310
_diffrn_reflns_theta_min         1.858
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.113
_exptl_crystal_description       block
_exptl_crystal_F_000             2160
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.23
_exptl_transmission_factor_max   0.981
_exptl_transmission_factor_min   0.973
_refine_diff_density_max         0.408
_refine_diff_density_min         -0.223
_refine_diff_density_rms         0.055
_refine_ls_abs_structure_details
;
 Flack x determined using 2526 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.3(6)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.080
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     646
_refine_ls_number_reflns         11053
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0857
_refine_ls_R_factor_gt           0.0590
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0656P)^2^+2.4168P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1475
_refine_ls_wR_factor_ref         0.1639
_reflns_Friedel_coverage         0.551
_reflns_Friedel_fraction_full    0.745
_reflns_Friedel_fraction_max     0.590
_reflns_number_gt                8345
_reflns_number_total             11053
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c8ce00097b2.cif
_cod_data_source_block           RSG-Boc-VV-OMe
_cod_depositor_comments
'Adding full bibliography for 7231043--7231044.cif.'
_cod_database_code               7231043
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              19250