A right handed peptide helix containing a central double D-amino acid segment.
Aravinda, Subrayashastry; Shamala, Narayanaswamy; Desiraju, Shrilakshmi; Balaram, Padmanabhan; Chemical communications (Cambridge, England)  (2002) 2454–2455; doi:10.1039/b207960g

data_7125576
_publ_section_title
;
 A right handed peptide helix containing a central double D-amino acid
 segment.
;
_journal_issue                   20
_journal_name_full
'Chemical communications (Cambridge, England)'
_journal_page_first              2454
_journal_page_last               2455
_journal_paper_doi               10.1039/b207960g
_journal_year                    2002
_chemical_formula_moiety         'C67 H121 N13 O16 * H2O'
_chemical_formula_sum            'C67 H121 N13 O17'
_chemical_formula_weight         1380.77
_chemical_name_systematic
; 
t-Butoxycarbonyl-leucyl-(alpha-aminoisobutyryl)-valyl-alanyl-leucyl-
(alpha-aminoisobutyryl)-valyl-D-alanyl-D-leucyl-(alpha-aminoisobutyryl)-leucyl
-(alpha-aminoisobutyryl)-valyl-methyl ester monohydrate

;
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_H-M   'P 1 21 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                 108.845(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   17.179(5)
_cell_length_b                   13.686(4)
_cell_length_c                   19.053(6)
_cell_measurement_temperature    293(2)
_cell_volume                     4239(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full .935
_diffrn_measured_fraction_theta_max .935
_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  0.0441
_diffrn_reflns_av_sigmaI/netI    0.0587
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            52023
_diffrn_reflns_theta_full        26.82
_diffrn_reflns_theta_max         26.82
_diffrn_reflns_theta_min         1.13
_exptl_absorpt_coefficient_mu    0.078
_exptl_crystal_colour            'colour less'
_exptl_crystal_density_diffrn    1.082
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1500
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.15
_refine_diff_density_max         .410
_refine_diff_density_min         -.296
_refine_diff_density_rms         .056
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   1.2(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.039
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     874
_refine_ls_number_reflns         16075
_refine_ls_number_restraints     6
_refine_ls_restrained_S_all      1.038
_refine_ls_R_factor_all          0.1592
_refine_ls_R_factor_gt           0.0868
_refine_ls_shift/su_max          0.209
_refine_ls_shift/su_mean         0.015
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1387P)^2^+0.4614P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2181
_refine_ls_wR_factor_ref         0.2629
_reflns_number_gt                8457
_reflns_number_total             16075
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b207960g.txt
_cod_data_source_block           luv13
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_symmetry_cell_setting' value 'Monoclinic' was changed to
'monoclinic' in accordance with the
/home/saulius/struct/COD-crude-data/automatic-downloads/DataCite-retrospective/RSC/depositions/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

Automatic conversion script
Id: cif_fix_values 6909 2019-04-08 15:41:33Z antanas 
;
_cod_original_sg_symbol_H-M      P21
_cod_database_code               7125576