Self-assembled dipeptide nanotubes constituted by flexible β-phenylalanine and conformationally constrained α,β-dehydrophenylalanine residues as drug delivery system
Parween, Shaheena; Misra, Anurag; Ramakumar, Suryanarayanarao; Chauhan, Virander Singh; Journal of Materials Chemistry B 2 (2014) 3096–; doi:10.1039/c3tb21856b

data_7235393
_publ_section_title
;
 Self-assembled dipeptide nanotubes constituted by flexible
 \b-phenylalanine and conformationally constrained
 \a,\b-dehydrophenylalanine residues as drug delivery system
;
_journal_issue                   20
_journal_name_full               'Journal of Materials Chemistry B'
_journal_page_first              3096
_journal_paper_doi               10.1039/c3tb21856b
_journal_volume                  2
_journal_year                    2014
_chemical_formula_moiety         '2(C19 H22 N2 O3), 1(H2 O1)'
_chemical_formula_sum            'C38 H46 N4 O7'
_chemical_formula_weight         670.8
_chemical_name_common            'PEPSEQ A=2 PHE*-PHE*'
_chemical_name_systematic
;

'(\b^3^-homophenylalanyl)-phenylalanine) hemihydrate'

;
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_cell_setting           orthorhombic
_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_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.7860(7)
_cell_length_b                   24.375(3)
_cell_length_c                   25.285(3)
_cell_measurement_temperature    296(2)
_cell_volume                     3566.0(7)
_computing_cell_refinement       'SAINTPLUS (BRUKER-AXS)'
_computing_data_collection       'KAPPA APEX II (BRUKER-AXS)'
_computing_data_reduction        'SAINTPLUS (BRUKER-AXS)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker Kappa APEX II CCD detector'
_diffrn_measurement_method       '\f and \w scans'
_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  0.1922
_diffrn_reflns_av_sigmaI/netI    0.2152
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       26
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            25027
_diffrn_reflns_theta_full        23.04
_diffrn_reflns_theta_max         23.04
_diffrn_reflns_theta_min         1.61
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_T_max  0.9983
_exptl_absorpt_correction_T_min  0.9787
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 2008)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.246
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'Rectangular rod'
_exptl_crystal_F_000             1424
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.03
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.388
_refine_diff_density_min         -0.231
_refine_diff_density_rms         0.052
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -1(3)
_refine_ls_extinction_coef       0.0025(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   0.972
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     428
_refine_ls_number_reflns         5003
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.972
_refine_ls_R_factor_all          0.2237
_refine_ls_R_factor_gt           0.0781
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0807P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1468
_refine_ls_wR_factor_ref         0.2077
_reflns_number_gt                2053
_reflns_number_total             5003
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3tb21856b2.cif
_cod_data_source_block           bff
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_symmetry_cell_setting' value 'Orthorhombic' was changed
to 'orthorhombic' 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_database_code               7235393