Stability-indicating chromatographic determination of hydroquinone in combination with tretinoin and fluocinolone acetonide in pharmaceutical formulation with photodegradation kinetic study
Abbas, Samah Sayed; Refaat, Mohamed; bebawy, lories; shokry, rafeek fahmy; RSC Adv.  (2015) –; doi:10.1039/C5RA07083J

data_7220214
_publ_section_title
;
 Stability-indicating chromatographic determination of hydroquinone in
 combination with tretinoin and fluocinolone acetonide in pharmaceutical
 formulation with photodegradation kinetic study
;
_journal_name_full               'RSC Adv.'
_journal_paper_doi               10.1039/C5RA07083J
_journal_year                    2015
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C24 H30 F2 O6'
_chemical_formula_sum            'C24 H30 F2 O6'
_chemical_formula_weight         452.49
_chemical_properties_physical    Photo-sensitive
_space_group_IT_number           19
_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   difmap
_atom_sites_solution_primary     direct
_audit_update_record
;
2015-04-28 deposited with the CCDC.
2015-05-07 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   9.1420(3)
_cell_length_b                   11.9074(4)
_cell_length_c                   20.3303(10)
_cell_measurement_reflns_used    4711
_cell_measurement_temperature    298
_cell_measurement_theta_max      27
_cell_measurement_theta_min      3
_cell_volume                     2213.10(15)
_computing_cell_refinement       'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 2001).'
_computing_data_reduction        'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'SHELXS 86 (Sheldrick, 1986)'
_diffrn_ambient_temperature      298
_diffrn_measured_fraction_theta_full 0.968
_diffrn_measured_fraction_theta_max 0.898
_diffrn_measurement_device       Area
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.082
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            8436
_diffrn_reflns_theta_full        25.225
_diffrn_reflns_theta_max         27.419
_diffrn_reflns_theta_min         2.982
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  0.99
_exptl_absorpt_correction_T_min  0.99
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            coulorless
_exptl_crystal_density_diffrn    1.358
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needels
_exptl_crystal_F_000             960
_exptl_crystal_size_max          0.430
_exptl_crystal_size_mid          0.390
_exptl_crystal_size_min          0.090
_refine_diff_density_max         0.33
_refine_diff_density_min         -0.31
_refine_ls_abs_structure_details 'Flack (1983), 0 Friedel-pairs'
_refine_ls_abs_structure_Flack   0(2)
_refine_ls_extinction_method     None
_refine_ls_goodness_of_fit_ref   0.9361
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     185
_refine_ls_number_reflns         1132
_refine_ls_number_restraints     103
_refine_ls_R_factor_all          0.1712
_refine_ls_R_factor_gt           0.0544
_refine_ls_shift/su_max          0.0071288
_refine_ls_shift/su_mean         0.0003116
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 Method, part 1, Chebychev polynomial, (Watkin, 1994, Prince, 1982) 
 [weight] = 1.0/[A~0~*T~0~(x)+A~1~*T~1~(x) ... +A~n-1~]*T~n-1~(x)] 
 where A~i~ are the Chebychev coefficients listed below and x= Fcalc/Fmax 
 Method = Robust Weighting (Prince, 1982) 
 W = [weight] * [1-(deltaF/6*sigmaF)^2^]^2^ 
 A~i~ are: 
 39.3 62.6 45.8 20.4 7.91 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1027
_refine_ls_wR_factor_gt          0.0673
_refine_ls_wR_factor_ref         0.0673
_reflns_limit_h_max              11
_reflns_limit_h_min              0
_reflns_limit_k_max              14
_reflns_limit_k_min              0
_reflns_limit_l_max              25
_reflns_limit_l_min              0
_reflns_number_gt                1132
_reflns_number_total             2569
_reflns_threshold_expression     I>2.0\s(I)
_oxford_diffrn_Wilson_B_factor   1.97
_oxford_diffrn_Wilson_scale      25.84
_oxford_refine_ls_r_factor_ref   0.0544
_oxford_refine_ls_scale          0.25014(14)
_oxford_reflns_number_all        2569
_oxford_reflns_threshold_expression_ref I>2.0\s(I)
_cod_data_source_file            c5ra07083j1.cif
_cod_data_source_block           1
_cod_original_cell_volume        2213.10(11)
_cod_original_sg_symbol_H-M      'P 21 21 21 '
_cod_database_code               7220214