Isocombretastatins a versus combretastatins a: the forgotten isoCA-4 isomer as a highly promising cytotoxic and antitubulin agent.
Messaoudi, Samir; Tréguier, Bret; Hamze, Abdallah; Provot, Olivier; Peyrat, Jean-François; De Losada, Jordi Rodrigo; Liu, Jian-Miao; Bignon, Jérôme; Wdzieczak-Bakala, Joanna; Thoret, Sylviane; Dubois, Joëlle; Brion, Jean-Daniel; Alami, Mouâd; Journal of medicinal chemistry 52 (2009) 4538–4542; doi:10.1021/jm900321u

data_1503667
_publ_section_title
;
 Isocombretastatins a versus combretastatins a: the forgotten isoCA-4
 isomer as a highly promising cytotoxic and antitubulin agent.
;
_journal_issue                   14
_journal_name_full               'Journal of medicinal chemistry'
_journal_page_first              4538
_journal_page_last               4542
_journal_paper_doi               10.1021/jm900321u
_journal_volume                  52
_journal_year                    2009
_chemical_formula_sum            'C18 H20 O5'
_chemical_formula_weight         316.34
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00(5)
_cell_angle_beta                 104.00(5)
_cell_angle_gamma                90.00(5)
_cell_formula_units_Z            4
_cell_length_a                   10.8340(10)
_cell_length_b                   11.6230(10)
_cell_length_c                   13.5110(10)
_cell_measurement_temperature    293(2)
_cell_volume                     1650.8(4)
_computing_cell_refinement
'DENZO (Otwinowski & Minor, 1997) COLLECT (Hooft, 1998)'
_computing_data_collection
'DENZO (Otwinowski & Minor, 1997) COLLECT (Hooft, 1998)'
_computing_data_reduction        'HKL package (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'PLATON (Spek, 1980-2004)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full .998
_diffrn_measured_fraction_theta_max .998
_diffrn_measurement_device_type  'Nonius kappa-CCD diffractometer'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0239
_diffrn_reflns_av_sigmaI/netI    0.0323
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            6487
_diffrn_reflns_theta_full        26.34
_diffrn_reflns_theta_max         26.34
_diffrn_reflns_theta_min         1.94
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.273
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             672
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.28
_refine_diff_density_max         .142
_refine_diff_density_min         -.154
_refine_diff_density_rms         .034
_refine_ls_extinction_coef       0.025(3)
_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   1.021
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     221
_refine_ls_number_reflns         3364
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.021
_refine_ls_R_factor_all          0.0692
_refine_ls_R_factor_gt           0.0443
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0645P)^2^+0.2773P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1126
_refine_ls_wR_factor_ref         0.1267
_reflns_number_gt                2371
_reflns_number_total             3364
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jm900321u_si_002.cif
_cod_data_source_block           shelxs97
_cod_original_cell_volume        1650.8(2)
_cod_original_sg_symbol_H-M      P21/C
_cod_database_code               1503667