data_2008894
_journal_name_full  'Acta Crystallographica'
_journal_year  1999
_journal_volume  C55
_journal_page_first  1515
_journal_page_last  1517
_publ_section_title
;
Two tetramethylxanthendiones
;
loop_
_publ_author_name
  'Jeyakanthan, J.'
  'Shanmuga Sundara Raj, S.'
  'Velmurugan, D.'
  'Hoong-Kun Fun'
  'Murugan, P.'
_chemical_formula_sum  'C17 H22 O3'
_chemical_formula_weight  274.35
_symmetry_cell_setting  triclinic
_symmetry_space_group_name_H-M  'P -1'
loop_
_symmetry_equiv_pos_as_xyz
  'x, y, z'
  '-x, -y, -z'
_cell_length_a  7.1458(8)
_cell_length_b  9.7690(12)
_cell_length_c  11.886(2)
_cell_angle_alpha  110.784(10)
_cell_angle_beta  96.074(11)
_cell_angle_gamma  101.302(10)
_cell_volume  746.6(2)
_cell_formula_units_Z  2
_cell_measurement_temperature  293(2)
_exptl_crystal_density_diffrn  1.220
_diffrn_ambient_temperature  293(2)
_refine_ls_R_factor_obs  0.044
_refine_ls_wR_factor_obs  0.123
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_thermal_displace_type
_atom_site_calc_flag
_atom_site_refinement_flags
_atom_site_occupancy
_atom_site_disorder_group
_atom_site_type_symbol
  O1 0.7852(2) 0.5061(2) 0.28029(12) 0.0761(4) Uani d . 1 . O
  O2 0.5975(2) 0.02904(13) -0.13310(11) 0.0615(3) Uani d . 1 . O
  C1 0.2370(2) 0.5633(2) 0.19326(11) 0.0397(3) Uani d . 1 . C
  H1A 0.1003(2) 0.5236(2) 0.19037(11) 0.048 Uiso calc R 1 . H
  H1B 0.2473(2) 0.6417(2) 0.16034(11) 0.048 Uiso calc R 1 . H
  C1a 0.3158(2) 0.43922(14) 0.11492(11) 0.0342(3) Uani d . 1 . C
  C2 0.3449(2) 0.6334(2) 0.32762(12) 0.0399(3) Uani d . 1 . C
  C3 0.5637(2) 0.6611(2) 0.32900(13) 0.0483(4) Uani d . 1 . C
  H3A 0.6029(2) 0.7417(2) 0.30013(13) 0.058 Uiso calc R 1 . H
  H3B 0.6316(2) 0.6956(2) 0.41301(13) 0.058 Uiso calc R 1 . H
  C4 0.6265(2) 0.5252(2) 0.25217(13) 0.0446(4) Uani d . 1 . C
  C4a 0.4923(2) 0.41779(15) 0.13936(11) 0.0368(3) Uani d . 1 . C
  C5 0.4407(2) 0.0591(2) -0.14490(13) 0.0402(3) Uani d . 1 . C
  C5a 0.4023(2) 0.19178(15) -0.05267(12) 0.0363(3) Uani d . 1 . C
  C6 0.2837(2) -0.0356(2) -0.25656(12) 0.0421(3) Uani d . 1 . C
  H6A 0.2961(2) -0.1390(2) -0.28518(12) 0.051 Uiso calc R 1 . H
  H6B 0.3055(2) 0.0013(2) -0.32104(12) 0.051 Uiso calc R 1 . H
  C7 0.0753(2) -0.03632(15) -0.23626(11) 0.0365(3) Uani d . 1 . C
  C8 0.0637(2) 0.12882(15) -0.17382(12) 0.0377(3) Uani d . 1 . C
  H8A 0.0628(2) 0.17465(15) -0.23407(12) 0.045 Uiso calc R 1 . H
  H8B -0.0575(2) 0.12960(15) -0.14408(12) 0.045 Uiso calc R 1 . H
  C8a 0.2284(2) 0.22124(14) -0.06957(11) 0.0341(3) Uani d . 1 . C
  C9 0.5590(2) 0.2886(2) 0.05666(13) 0.0420(3) Uani d . 1 . C
  H9A 0.5931(2) 0.2281(2) 0.10128(13) 0.050 Uiso calc R 1 . H
  H9B 0.6741(2) 0.3274(2) 0.02980(13) 0.050 Uiso calc R 1 . H
  O10 0.18044(13) 0.34485(10) 0.01077(8) 0.0396(3) Uani d . 1 . O
  C11 0.2960(3) 0.7845(2) 0.39244(14) 0.0592(5) Uani d . 1 . C
  H11A 0.3678(14) 0.8314(7) 0.4752(4) 0.089 Uiso calc R 1 . H
  H11B 0.1592(4) 0.7671(2) 0.3932(10) 0.089 Uiso calc R 1 . H
  H11C 0.3302(16) 0.8498(5) 0.3496(7) 0.089 Uiso calc R 1 . H
  C12 0.2835(2) 0.5277(2) 0.39299(14) 0.0554(4) Uani d . 1 . C
  H12A 0.3504(13) 0.5734(6) 0.4769(3) 0.083 Uiso calc R 1 . H
  H12B 0.3156(16) 0.4334(5) 0.3531(7) 0.083 Uiso calc R 1 . H
  H12C 0.1458(4) 0.5097(11) 0.3901(10) 0.083 Uiso calc R 1 . H
  C13 -0.0660(2) -0.1106(2) -0.35978(12) 0.0512(4) Uani d . 1 . C
  H13A -0.0583(12) -0.2132(4) -0.3995(5) 0.077 Uiso calc R 1 . H
  H13B -0.0321(11) -0.0556(8) -0.4106(4) 0.077 Uiso calc R 1 . H
  H13C -0.1961(3) -0.1097(12) -0.34669(15) 0.077 Uiso calc R 1 . H
  C14 0.0221(2) -0.1254(2) -0.15619(13) 0.0444(4) Uani d . 1 . C
  H14A 0.0322(14) -0.2273(4) -0.1961(5) 0.067 Uiso calc R 1 . H
  H14B -0.1088(5) -0.1264(10) -0.1440(8) 0.067 Uiso calc R 1 . H
  H14C 0.1095(9) -0.0783(7) -0.0783(4) 0.067 Uiso calc R 1 . H
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
  O1 0.0366(7) 0.0953(10) 0.0655(8) 0.0220(6) -0.0093(6) -0.0027(7)
  O2 0.0380(6) 0.0614(7) 0.0729(8) 0.0227(5) 0.0150(6) 0.0050(6)
  C1 0.0397(7) 0.0414(7) 0.0343(7) 0.0158(6) 0.0042(6) 0.0082(6)
  C1a 0.0338(7) 0.0360(6) 0.0294(6) 0.0093(5) 0.0042(5) 0.0087(5)
  C2 0.0405(8) 0.0406(7) 0.0318(6) 0.0103(6) 0.0046(6) 0.0066(5)
  C3 0.0398(8) 0.0456(8) 0.0421(7) 0.0007(6) 0.0009(6) 0.0035(6)
  C4 0.0296(7) 0.0528(9) 0.0412(7) 0.0052(6) 0.0031(6) 0.0099(6)
  C4a 0.0307(7) 0.0403(7) 0.0352(6) 0.0075(6) 0.0043(5) 0.0108(5)
  C5 0.0341(7) 0.0404(7) 0.0451(7) 0.0113(6) 0.0150(6) 0.0123(6)
  C5a 0.0324(7) 0.0373(7) 0.0357(6) 0.0088(6) 0.0076(5) 0.0096(5)
  C6 0.0449(8) 0.0399(7) 0.0377(7) 0.0115(6) 0.0161(6) 0.0076(6)
  C7 0.0352(7) 0.0370(7) 0.0306(6) 0.0064(6) 0.0040(5) 0.0073(5)
  C8 0.0327(7) 0.0415(7) 0.0340(6) 0.0105(6) 0.0027(5) 0.0091(5)
  C8a 0.0337(7) 0.0345(6) 0.0311(6) 0.0098(5) 0.0056(5) 0.0087(5)
  C9 0.0295(7) 0.0462(8) 0.0436(7) 0.0128(6) 0.0045(6) 0.0085(6)
  O10 0.0348(5) 0.0412(5) 0.0344(5) 0.0158(4) -0.0006(4) 0.0033(4)
  C11 0.0668(11) 0.0535(9) 0.0426(8) 0.0224(8) 0.0058(8) -0.0015(7)
  C12 0.0515(10) 0.0710(11) 0.0470(8) 0.0138(8) 0.0113(7) 0.0268(8)
  C13 0.0554(10) 0.0485(8) 0.0353(7) 0.0082(7) -0.0016(7) 0.0047(6)
  C14 0.0422(8) 0.0449(8) 0.0425(7) 0.0065(6) 0.0096(6) 0.0145(6)
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_site_symmetry_2
_geom_bond_distance
_geom_bond_publ_flag
  O1 C4 . 1.217(2) yes
  O2 C5 . 1.219(2) yes
  C1 C1a . 1.494(2) ?
  C1 C2 . 1.540(2) ?
  C1a C4a . 1.338(2) y
  C1a O10 . 1.3802(15) yes
  C2 C12 . 1.526(2) ?
  C2 C3 . 1.530(2) ?
  C2 C11 . 1.532(2) ?
  C3 C4 . 1.503(2) ?
  C4 C4a . 1.467(2) y
  C4a C9 . 1.497(2) yes
  C5 C5a . 1.467(2) y
  C5 C6 . 1.511(2) ?
  C5a C8a . 1.340(2) y
  C5a C9 . 1.497(2) yes
  C6 C7 . 1.533(2) ?
  C7 C14 . 1.530(2) ?
  C7 C13 . 1.531(2) ?
  C7 C8 . 1.541(2) ?
  C8 C8a . 1.489(2) ?
  C8a O10 . 1.3786(15) yes