Isolation, Structure Elucidation and Racemization of (+)- and (−)-Pratensilins A–C, Unprecedented Spiro Indolinone-naphthofuran Alkaloids from a Marine Streptomyces sp.
Zhang, Shumin; Yang, Qin; Guo, Lin; Zhang, Ying; Feng, Lingling; Zhou, Ling; Yang, Shengxiang; Yao, Qingshou; Pescitelli, Gennaro; Zeping, Xie; Chem. Commun.  (2017) –; doi:10.1039/C7CC04983H

data_7120578
_publ_section_title
;
 Isolation, Structure Elucidation and Racemization of (+)- and
 (&#x2212;)-Pratensilins A--C, Unprecedented Spiro Indolinone-naphthofuran
 Alkaloids from a Marine Streptomyces sp.
;
_journal_name_full               'Chem. Commun.'
_journal_paper_doi               10.1039/C7CC04983H
_journal_year                    2017
_chemical_formula_moiety         'C20 H15 N O4, 0.5(H2 O)'
_chemical_formula_sum            'C20 H16 N O4.5'
_chemical_formula_weight         342.34
_chemical_name_systematic        Lactamycin
_chemical_properties_physical    'protic solvent'
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2016-04-15 deposited with the CCDC.
2017-08-18 downloaded from the CCDC.
;
_cell_angle_alpha                94.1390(10)
_cell_angle_beta                 95.1400(10)
_cell_angle_gamma                109.6890(10)
_cell_formula_units_Z            4
_cell_length_a                   8.5611(2)
_cell_length_b                   11.5649(3)
_cell_length_c                   17.2271(5)
_cell_measurement_reflns_used    9983
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      69.28
_cell_measurement_theta_min      2.59
_cell_volume                     1589.89(7)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.946
_diffrn_measured_fraction_theta_max 0.946
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0337
_diffrn_reflns_av_sigmaI/netI    0.0263
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            24293
_diffrn_reflns_theta_full        66.99
_diffrn_reflns_theta_max         66.99
_diffrn_reflns_theta_min         2.59
_exptl_absorpt_coefficient_mu    0.843
_exptl_absorpt_correction_T_max  0.9512
_exptl_absorpt_correction_T_min  0.8496
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.430
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             716
_exptl_crystal_recrystallization_method 'Re-crystallisation from solvent'
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.268
_refine_diff_density_min         -0.250
_refine_diff_density_rms         0.049
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.020
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     472
_refine_ls_number_reflns         5373
_refine_ls_number_restraints     3
_refine_ls_restrained_S_all      1.021
_refine_ls_R_factor_all          0.0384
_refine_ls_R_factor_gt           0.0366
_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^)+(0.0523P)^2^+0.6307P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0943
_refine_ls_wR_factor_ref         0.0961
_reflns_number_gt                5060
_reflns_number_total             5373
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c7cc04983h2.cif
_cod_data_source_block           cu_xzp_r714_0m
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 

2017-11-17
Z value and formula fixed to values more according to usual
chemical conventions.                 miguel
;
_cod_original_formula_moiety     '2(C20 H15 N O4), H2 O'
_cod_original_formula_sum        'C40 H32 N2 O9'
_cod_original_formula_units_Z    2
_cod_original_formula_weight     684.68
_cod_database_code               7120578
_solvent_exptl_crystal_recrystallization_method 'MeOH and CH2Cl2'