Crystallographic Evidence of [1,5]Prototropic Shifts Occurring upon Transannular Diels–Alder Reaction of a 14-Membered Macrocycle leading to a 5α-Steroid Skeleton
Drouin, Marc; Couturier, Michel; Deslongchamps, Pierre; Acta Crystallographica Section C 54 (1998) 256–261; doi:10.1107/S0108270197013310

data_2007008
_publ_section_title
;
 Crystallographic Evidence of [1,5]Prototropic Shifts Occurring upon
 Transannular Diels--Alder Reaction of a 14-Membered Macrocycle leading
 to a 5\a-Steroid Skeleton
;
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              256
_journal_page_last               261
_journal_paper_doi               10.1107/S0108270197013310
_journal_volume                  54
_journal_year                    1998
_chemical_formula_iupac          'C24 H30 O8'
_chemical_formula_sum            'C24 H30 O8'
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_chemical_name_systematic
;
rac-3,3-Bis(methoxycarbonyl)-18-oxo-5\a-androst-6-en-11,17-dione
;
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'NRCVAX DATRD2  (Gabe, Le Page, Charland, Lee & White, 1989)'
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_computing_structure_solution    'NRCVAX SOLVER'
_diffrn_ambient_temperature      293.0(10)
_diffrn_measurement_device       'Nonius CAD-4    '
_diffrn_measurement_method       '\w/2\q scan '
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
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_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.1126P)^2^+0.0750P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.1126P)^2^+0.0750P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to 'w =
1/[\s^2^(Fo^2^)+(0.1126P)^2^+0.0750P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        4566.0(4)
_cod_database_code               2007008