Hydrophobic α,α-Disubstituted Disilylated TESDpg Induces Incipient 310-Helix in Short Tripeptide Sequence
Fanelli, Roberto; Berthomieu, Dorothée; Didierjean, Claude; Doudouh, Abdelatif; Lebrun, Aurélien; Martinez, Jean; Cavelier, Florine; Organic Letters  (2017) –; doi:10.1021/acs.orglett.7b01172

data_1546040
_publ_section_title
;
 Hydrophobic \a,\a-Disubstituted Disilylated TESDpg Induces Incipient
 310-Helix in Short Tripeptide Sequence
;
_journal_name_full               'Organic Letters'
_journal_paper_doi               10.1021/acs.orglett.7b01172
_journal_year                    2017
_chemical_absolute_configuration syn
_chemical_formula_sum            'C37 H68 N4 O5 Si2'
_chemical_formula_weight         705.13
_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
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            12
_cell_length_a                   12.69260(10)
_cell_length_b                   21.4026(2)
_cell_length_c                   47.9632(3)
_cell_measurement_reflns_used    52132
_cell_measurement_temperature    100.9(6)
_cell_measurement_theta_max      76.4510
_cell_measurement_theta_min      3.4130
_cell_volume                     13029.43(18)
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      100.9(6)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Atlas'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0310
_diffrn_reflns_av_unetI/netI     0.0239
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       58
_diffrn_reflns_limit_l_min       -50
_diffrn_reflns_number            106249
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.989
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         76.609
_diffrn_reflns_theta_min         3.451
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    1.061
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.37540
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.38.41r (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_density_diffrn    1.078
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             4632
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.353
_refine_diff_density_min         -0.351
_refine_diff_density_rms         0.040
_refine_ls_abs_structure_details
;
 Flack x determined using 11386 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.010(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.060
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1352
_refine_ls_number_reflns         27092
_refine_ls_number_restraints     30
_refine_ls_restrained_S_all      1.071
_refine_ls_R_factor_all          0.0381
_refine_ls_R_factor_gt           0.0357
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0477P)^2^+4.1021P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0909
_refine_ls_wR_factor_ref         0.0940
_reflns_Friedel_coverage         0.838
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.985
_reflns_number_gt                26159
_reflns_number_total             27092
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol7b01172_si_002.cif
_cod_data_source_block           fr215
_cod_database_code               1546040
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              10661
_shelx_hkl_checksum              64411