Low pH-triggering Changes in Peptide Secondary Structures
Furukawa, Kaori; Oba, Makoto; Toyama, Kotomi; Opiyo, George Ouma; Demizu, Yosuke; Kurihara, Masaaki; Doi, Mitsunobu; Tanaka, Masakazu; Org. Biomol. Chem.  (2017) –; doi:10.1039/C7OB01374D

data_7155724
_publ_section_title
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 Low pH-triggering Changes in Peptide Secondary Structures
;
_journal_name_full               'Org. Biomol. Chem.'
_journal_paper_doi               10.1039/C7OB01374D
_journal_year                    2017
_chemical_absolute_configuration rm
_chemical_compound_source        synthesis
_chemical_formula_moiety         'C59 H98 N8 O15, 1.5(C2 H6 O)'
_chemical_formula_sum            'C62 H107 N8 O16.5'
_chemical_formula_weight         1228.56
_chemical_name_systematic
; 
 Z-(Leu-Leu-AC6)2-Leu-Leu-OMe.3EtOH
;
_space_group_IT_number           1
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  'P 1'
_symmetry_space_group_name_H-M   'P 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2017-04-10 deposited with the CCDC.
2017-06-27 downloaded from the CCDC.
;
_cell_angle_alpha                84.06(3)
_cell_angle_beta                 70.79(3)
_cell_angle_gamma                86.23(3)
_cell_formula_units_Z            2
_cell_length_a                   11.908(2)
_cell_length_b                   17.703(4)
_cell_length_c                   17.953(4)
_cell_measurement_reflns_used    10073
_cell_measurement_temperature    93(2)
_cell_measurement_theta_max      27.4
_cell_measurement_theta_min      1.8
_cell_volume                     3552.7(14)
_computing_cell_refinement
;
CrystalClear-SM Expert 2.0 r16 (Rigaku, 2014)
;
_computing_data_collection
;
CrystalClear-SM Expert 2.0 r16 (Rigaku, 2014)
;
_computing_data_reduction
;
CrystalClear-SM Expert 2.0 r16 (Rigaku, 2014)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      93(2)
_diffrn_detector_area_resol_mean 28.5714
_diffrn_measured_fraction_theta_full 0.977
_diffrn_measured_fraction_theta_max 0.977
_diffrn_measurement_device_type
;
Rigaku Saturn724+ (4x4 bin mode)
;
_diffrn_measurement_method       'profile data from \w-scans'
_diffrn_radiation_monochromator  Confocal
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0781
_diffrn_reflns_av_sigmaI/netI    0.1408
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            26933
_diffrn_reflns_theta_full        25.35
_diffrn_reflns_theta_max         25.35
_diffrn_reflns_theta_min         1.81
_diffrn_source                   'Rotating Anode'
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.856
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.148
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Platelet
_exptl_crystal_F_000             1334
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.945
_refine_diff_density_min         -0.475
_refine_diff_density_rms         0.082
_refine_ls_abs_structure_details 'Flack (1983), 0 Friedel pairs'
_refine_ls_abs_structure_Flack   2.3(19)
_refine_ls_extinction_coef       0.0017(11)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.963
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           fullcycle
_refine_ls_number_parameters     1559
_refine_ls_number_reflns         12744
_refine_ls_number_restraints     3
_refine_ls_restrained_S_all      0.963
_refine_ls_R_factor_all          0.1642
_refine_ls_R_factor_gt           0.0998
_refine_ls_shift/su_max          0.011
_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1823P)^2^+2.0503P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2421
_refine_ls_wR_factor_ref         0.3067
_reflns_number_gt                6820
_reflns_number_total             12744
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            c7ob01374d2.cif
_cod_data_source_block           frk8
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 

2017-11-19
Z value and formula fixed to values more according to usual
chemical conventions.                 miguel
;
_cod_original_cell_volume        3552.7(12)
_cod_original_sg_symbol_H-M      P1
_cod_original_formula_moiety     '2(C59 H98 N8 O15), 3(C2 H6 O)'
_cod_original_formula_sum        'C124 H214 N16 O33 '
_cod_original_formula_units_Z    1
_cod_original_formula_weight     2457.12
_cod_database_code               7155724