Stereoselectivity of A-ring contraction for 3-oxotriterpenoids
Kacharov, Alexey D.; Yemets, Sergiy V.; Nemykin, Victor N.; Kacharova, Liliya M.; Fokin, Andrey A.; Krasutsky, Pavel A.; RSC Advances 3 (2013) 19057–; doi:10.1039/c3ra42929f

data_7239134
_publ_section_title
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 Stereoselectivity of A-ring contraction for 3-oxotriterpenoids
;
_journal_issue                   41
_journal_name_full               'RSC Advances'
_journal_page_first              19057
_journal_paper_doi               10.1039/c3ra42929f
_journal_volume                  3
_journal_year                    2013
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C31 H50 O4'
_chemical_formula_sum            'C31 H50 O4'
_chemical_formula_weight         486.74
_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_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_cell_angle_alpha                90
_cell_angle_beta                 90.01(3)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   7.4870(15)
_cell_length_b                   16.276(3)
_cell_length_c                   11.153(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    298
_cell_measurement_theta_max      18
_cell_measurement_theta_min      15
_cell_volume                     1359.1(4)
_computing_cell_refinement       'USER DEFINED CELL REFINEMENT'
_computing_data_collection       'USER DEFINED DATA COLLECTION'
_computing_data_reduction        'USER DEFINED DATA REDUCTION'
_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    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      298
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device       Serial
_diffrn_measurement_device_type  Unknown
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.000
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       0
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       0
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            3262
_diffrn_reflns_theta_full        27.520
_diffrn_reflns_theta_max         27.520
_diffrn_reflns_theta_min         2.503
_diffrn_standards_decay_%        0.00
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_T_max  0.98
_exptl_absorpt_correction_T_min  0.84
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(North et al., 1968)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.189
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             536
_exptl_crystal_size_max          0.510
_exptl_crystal_size_mid          0.430
_exptl_crystal_size_min          0.220
_refine_diff_density_max         0.46
_refine_diff_density_min         -0.34
_refine_ls_extinction_method     None
_refine_ls_goodness_of_fit_ref   0.9688
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     316
_refine_ls_number_reflns         3237
_refine_ls_number_restraints     1
_refine_ls_R_factor_all          0.0923
_refine_ls_R_factor_gt           0.0797
_refine_ls_shift/su_max          0.0000812
_refine_ls_shift/su_mean         0.0000118
_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: 
 8.84 11.7 3.37 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1995
_refine_ls_wR_factor_gt          0.1774
_refine_ls_wR_factor_ref         0.1995
_reflns_limit_h_max              9
_reflns_limit_h_min              -9
_reflns_limit_k_max              21
_reflns_limit_k_min              0
_reflns_limit_l_max              14
_reflns_limit_l_min              0
_reflns_number_gt                2631
_reflns_number_total             3252
_reflns_threshold_expression     I>2.0\s(I)
_oxford_diffrn_Wilson_B_factor   3.46
_oxford_diffrn_Wilson_scale      3.87
_oxford_refine_ls_r_factor_ref   0.0923
_oxford_refine_ls_scale          0.5570(19)
_oxford_reflns_number_all        3237
_oxford_reflns_threshold_expression_ref I>-10.0\s(I)
_cod_data_source_file            c3ra42929f.txt
_cod_data_source_block           1
_cod_original_cell_volume        1359.1(5)
_cod_original_sg_symbol_H-M      'P 1 21 1 '
_cod_database_code               7239134
_iucr_refine_instruction_details_constraints
;
BLOCK SCALE X'S, U'S 
RIDE C   (   9,X'S) H   (  91,X'S) 
RIDE C   (  13,X'S) H   ( 131,X'S) 
RIDE C   (  18,X'S) H   ( 181,X'S) 
RIDE C   (  16,X'S) H   ( 161,X'S) H   ( 162,X'S) 
RIDE C   (  15,X'S) H   ( 151,X'S) H   ( 152,X'S) 
RIDE C   (  28,X'S) H   ( 282,X'S) H   ( 281,X'S) 
RIDE C   (  19,X'S) H   ( 191,X'S) 
RIDE C   (  21,X'S) H   ( 212,X'S) H   ( 211,X'S) 
RIDE C   (  22,X'S) H   ( 221,X'S) H   ( 222,X'S) 
RIDE C   (  29,X'S) H   ( 291,X'S) H   ( 292,X'S) H   ( 293,X'S) 
RIDE C   (  30,X'S) H   ( 301,X'S) H   ( 302,X'S) H   ( 303,X'S) 
RIDE C   (  12,X'S) H   ( 121,X'S) H   ( 122,X'S) 
RIDE C   (  11,X'S) H   ( 112,X'S) H   ( 111,X'S) 
RIDE C   (  27,X'S) H   ( 271,X'S) H   ( 272,X'S) H   ( 273,X'S) 
RIDE C   (   7,X'S) H   (  71,X'S) H   (  72,X'S) 
RIDE C   (   6,X'S) H   (  62,X'S) H   (  61,X'S) 
RIDE C   (   5,X'S) H   (  51,X'S) 
RIDE C   (   1,X'S) H   (  12,X'S) H   (  11,X'S) 
RIDE C   (  31,X'S) H   ( 311,X'S) H   ( 313,X'S) H   ( 312,X'S) 
RIDE O   (   2,X'S) H   (  21,X'S) 
RIDE C   (  23,X'S) H   ( 233,X'S) H   ( 232,X'S) H   ( 231,X'S) 
RIDE C   (  24,X'S) H   ( 243,X'S) H   ( 242,X'S) H   ( 241,X'S) 
RIDE C   (  26,X'S) H   ( 263,X'S) H   ( 262,X'S) H   ( 261,X'S) 
RIDE C   (  25,X'S) H   ( 253,X'S) H   ( 252,X'S) H   ( 251,X'S) 
END                                                                             
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_iucr_refine_instruction_details_restraints
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NO 
REM   HREST   START (DO NOT REMOVE THIS LINE) 
REM   HREST   END (DO NOT REMOVE THIS LINE) 
END                                                                             
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