Download citation
Download citation
link to html
This work presents the crystal structure determination of two elusive polymorphs of furazidin, an antibacterial agent, employing a combination of crystal structure prediction (CSP) calculations and an NMR crystallography approach. Two previously uncharacterized neat crystal forms, one of which has two symmetry-independent molecules (form I), whereas the other one is a Z′ = 1 polymorph (form II), crystallize in P21/c and P1 space groups, respectively, and both are built by different conformers, displaying different intermolecular interactions. It is demonstrated that the usage of either CSP or NMR crystallography alone is insufficient to successfully elucidate the above-mentioned crystal structures, especially in the case of the Z′ = 2 polymorph. In addition, cases of serendipitous agreement in terms of 1H or 13C NMR data obtained for the CSP-generated crystal structures different from the ones observed in the laboratory (false-positive matches) are analyzed and described. While for the majority of analyzed crystal structures the obtained agreement with the NMR experiment is indicative of some structural features in common with the experimental structure, the mentioned serendipity observed in exceptional cases points to the necessity of caution when using an NMR crystallography approach in crystal structure determination.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S205252062000373X/xk5066sup1.cif
Contains datablocks furazidin_formII, furazidin_formI

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S205252062000373X/xk5066furazidin_formIIsup2.hkl
Contains datablock furazidin_formII

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S205252062000373X/xk5066furazidin_formIsup3.hkl
Contains datablock furazidin_formI

txt

Text file https://doi.org/10.1107/S205252062000373X/xk5066sup4.txt
Structure of furazidin form I in cif file generated by CSP calculations

txt

Text file https://doi.org/10.1107/S205252062000373X/xk5066sup5.txt
Powder X-ray data for furazidin form I

txt

Text file https://doi.org/10.1107/S205252062000373X/xk5066sup6.txt
Powder X-ray data for furazidin form II

txt

Text file https://doi.org/10.1107/S205252062000373X/xk5066sup7.txt
Structure of furazidin form II in cif file generated by CSP calculations

txt

Text file https://doi.org/10.1107/S205252062000373X/xk5066sup8.txt
Structure of furazidin form I in cif file generated by CSP calculations and optimized at DFT-D2 level of theory

txt

Text file https://doi.org/10.1107/S205252062000373X/xk5066sup9.txt
Structure of furazidin form II in cif file generated by CSP calculations and optimized at DFT-D2 level of theory

pdf

Portable Document Format (PDF) file https://doi.org/10.1107/S205252062000373X/xk5066sup10.pdf
Supporting information figures and tables

CCDC references: 1993854; 1993855

Computing details top

For both structures, program(s) used to refine structure: GSAS-II (Toby & Von Dreele, J. Appl. Cryst. 46, 544-549, 2013).

(furazidin_formII) top
Crystal data top
C10H8N4O5β = 106.848 (14)°
Mr = 264.2V = 1087.80 (18) Å3
Monoclinic, P21/cZ = 4
Hall symbol: -P 2ybcDx = 1.613 Mg m3
a = 11.670 (7) ÅCu Kα radiation
b = 11.4666 (12) ÅT = 300 K
c = 8.494 (4) Å
Data collection top
Bruker D8 with LYNXEYE detector
diffractometer
Refinement top
Least-squares matrix: fullR(F2) = 0.04496
Rp = 0.0711921 data points
Rwp = 0.09632 parameters
Rexp = 0.316Background function: Background function: "chebyschev" function with 24 terms: 6.39(6), -11.28(29), -1.7(8), 1.0(22), 209.4(24), 78(4), -2446.0(10), -1372.6(11), 20455.6(21), 11208(3), -117679.9(15), -34269(4), 414751.5(7), 26568.1(15), -893273.9(17), 87213.0(23), 1.1848209(23)e6, -251999(5), -945917.0(18), 281839(4), 417242.8(5), -151823.0(10), -78161(3), 32564(7),
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
H10.827870.062531.005130.010*
H50.847400.199031.078170.010*
H90.681800.048560.802190.010*
H130.393440.372730.398850.010*
H170.590010.093010.522720.010*
H210.490480.074300.645690.010*
H250.999000.183111.237610.010*
H291.182760.110851.502290.010*
C11.107620.058231.417470.010*
C50.962420.002111.209380.010*
C91.022830.096171.281100.010*
C130.863020.016641.069790.010*
C170.812920.119711.013470.010*
C210.716060.128340.868140.010*
C250.532590.338980.615280.010*
C290.432000.194450.441590.010*
C330.527670.136930.576930.010*
C371.116550.059891.415120.010*
N10.672650.229730.818090.010*
N50.582630.233830.679640.010*
N90.443560.311040.472030.010*
N131.175860.139971.526470.010*
O11.015140.097871.294680.010*
O51.262750.102191.634540.010*
O91.145150.242561.509090.010*
O130.560280.434410.672320.010*
O170.360650.146390.328180.010*
Geometric parameters (Å, º) top
H1—C131.0786C25—O131.2024
H5—C171.0784C29—C331.5030
H9—C211.0866C29—N91.3609
H13—N91.0091C29—O171.2083
H17—C331.0904C33—H171.0904
H21—C331.0919C33—H211.0919
H25—C91.0715C33—C291.5030
H29—C371.0748C33—N51.4432
C1—C371.3590C37—H291.0748
C1—N131.3937C37—C11.3590
C1—O11.3442C37—C91.394
C5—C91.3745N1—C211.2900
C5—C131.4078N1—N51.3314
C5—O11.3605N5—C251.3814
C9—H251.0715N5—C331.4432
C9—C51.3745N5—N11.3314
C9—C371.394N9—H131.0091
C13—H11.0786N9—C251.3891
C13—C51.4078N9—C291.3609
C13—C171.3435N13—C11.3937
C17—H51.0784N13—O51.2325
C17—C131.3435N13—O91.2261
C17—C211.4150O1—C11.3442
C21—H91.0866O1—C51.3605
C21—C171.4150O5—N131.2325
C21—N11.2900O9—N131.2261
C25—N51.3814O13—C251.2024
C25—N91.3891O17—C291.2083
C37—C1—N13130.432C33—C29—O17126.661
C37—C1—O1111.923N9—C29—O17127.372
N13—C1—O1117.625H17—C33—H21109.84
C9—C5—C13131.449H17—C33—C29108.566
C9—C5—O1109.328H21—C33—C29112.046
C13—C5—O1119.214H17—C33—N5112.139
H25—C9—C5124.159H21—C33—N5111.035
H25—C9—C37128.531C29—C33—N5103.056
C5—C9—C37107.31H29—C37—C1125.073
H1—C13—C5115.348H29—C37—C9129.608
H1—C13—C17119.802C1—C37—C9105.312
C5—C13—C17124.841C21—N1—N5117.189
H5—C17—C13120.056C25—N5—C33111.713
H5—C17—C21118.114C25—N5—N1121.01
C13—C17—C21121.822C33—N5—N1127.253
H9—C21—C17118.189H13—N9—C25122.056
H9—C21—N1122.557H13—N9—C29124.317
C17—C21—N1119.251C25—N9—C29113.627
N5—C25—N9105.567C1—N13—O5116.533
N5—C25—O13126.973C1—N13—O9118.324
N9—C25—O13127.458O5—N13—O9125.141
C33—C29—N9105.961C1—O1—C5106.127
(furazidin_formI) top
Crystal data top
C20H16N8O10β = 92.16 (3)°
Mr = 528.39γ = 97.31 (11)°
Triclinic, P1V = 1138.5 (4) Å3
Hall symbol: -P 1Z = 2
a = 22.18 (2) ÅDx = 1.541 Mg m3
b = 12.546 (7) ÅCu Kα radiation
c = 5.3092 (16) ÅT = 300 K
α = 51.074 (3)°
Data collection top
Bruker D8 with LYNXEYE detector
diffractometer
Refinement top
Least-squares matrix: fullR(F2) = 0.00000
Rp = 0.0731921 data points
Rwp = 0.13210 parameters
Rexp = 0.013Background function: Background function: "chebyschev" function with 24 terms: 4846.854, -11028.729, -20160.862, 256317.539, 592987.724, -5.249158441e6, -3.631253229e6, 4.6716624983e7, 2.478157997e6, -2.22566966249e8, 5.3300222852e7, 6.38125053237e8, -2.55142761173e8, -1.156971410908e9, 5.82828782201e8, 1.333696204767e9, -7.80463244314e8, -9.38678820304e8, 6.25995183217e8, 3.54965933309e8, -2.79499578917e8, -4.3505635500e7, 5.3561337350e7, -6.779782588e6,
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
H10.734370.648320.616970.010*
H30.620660.525610.484750.010*
H50.636370.705150.703680.010*
H70.392860.759470.768950.010*
H90.563800.716491.020600.010*
H110.572570.866940.604500.010*
H130.678160.423910.328400.010*
H150.781380.351870.248150.010*
C10.822790.467830.405750.010*
C30.740390.526540.468400.010*
C50.723840.449470.366470.010*
C70.707850.591860.549570.010*
C90.646740.584070.548030.010*
C110.612830.647670.630130.010*
C130.459120.678480.673240.010*
C150.483240.814490.821130.010*
C170.541890.775300.787400.010*
C190.776790.412060.325700.010*
N10.554500.633680.614990.010*
N30.521510.691790.690550.010*
N50.438330.752800.756540.010*
N70.885180.461100.418770.010*
O10.801790.538030.491650.010*
O30.903640.391900.351360.010*
O50.917670.522780.495710.010*
O70.428250.616070.600010.010*
O90.477080.887730.893740.010*
H170.046690.909020.969630.010*
H190.103630.764030.755630.010*
H210.155910.926370.993880.010*
H230.402870.901440.954460.010*
H250.249451.061390.864810.010*
H270.245270.908391.276390.010*
H290.002650.692690.645180.010*
H310.118520.689670.592370.010*
C210.106090.804510.779350.010*
C230.008650.810210.815700.010*
C250.026530.739080.699380.010*
C270.047790.850950.882100.010*
C290.101470.822880.840100.010*
C310.156940.867190.907970.010*
C330.312580.847590.893300.010*
C350.334970.980191.052330.010*
C370.266950.962161.036320.010*
C390.089100.736370.673840.010*
N90.206930.836530.864630.010*
N110.258430.880000.928810.010*
N130.357390.908810.967950.010*
N150.162890.832350.809840.010*
O110.058090.849790.866890.010*
O130.206700.796340.714460.010*
O150.166670.890970.927500.010*
O170.319390.777750.811750.010*
O190.364171.044871.123930.010*
Geometric parameters (Å, º) top
H1—C71.0828H17—C271.0853
H3—C91.0830H19—C291.0841
H5—C111.09H21—C311.0910
H7—N51.0308H23—O91.7392
H7—O171.7172H23—N131.0341
H9—C171.1006H25—C371.0961
H11—C171.0844H27—C371.0928
H13—C51.0744H29—C251.0773
H15—C191.0787H31—C391.0754
C1—C191.3678C21—C391.3734
C1—N71.3937C21—N151.3908
C1—O11.3512C21—O111.3466
C3—C51.3838C23—C251.3853
C3—C71.4127C23—C271.4084
C3—O11.3605C23—O111.3616
C5—H131.0744C25—H291.0773
C5—C31.3838C25—C231.3853
C5—C191.3905C25—C391.3877
C7—H11.0828C27—H171.0853
C7—C31.4127C27—C231.4084
C7—C91.3468C27—C291.3479
C9—H31.0830C29—H191.0841
C9—C71.3468C29—C271.3479
C9—C111.4167C29—C311.4134
C11—H51.09C31—H211.0910
C11—C91.4167C31—C291.4134
C11—N11.2898C31—N91.2920
C13—N31.3792C33—N111.3716
C13—N51.3858C33—N131.3760
C13—O71.2081C33—O171.2221
C15—C171.5026C35—C371.5041
C15—N51.3494C35—N131.3727
C15—O91.2217C35—O191.2075
C17—H91.1006C37—H251.0961
C17—H111.0844C37—H271.0928
C17—C151.5026C37—C351.5041
C17—N31.4510C37—N111.4511
C19—H151.0787C39—H311.0754
C19—C11.3678C39—C211.3734
C19—C51.3905C39—C251.3877
N1—C111.2898N9—C311.2920
N1—N31.3241N9—N111.3284
N3—C131.3792N11—C331.3716
N3—C171.4510N11—C371.4511
N3—N11.3241N11—N91.3284
N5—H71.0308N13—H231.0341
N5—C131.3858N13—C331.3760
N5—C151.3494N13—C351.3727
N7—C11.3937N15—C211.3908
N7—O31.2415N15—O131.2424
N7—O51.2322N15—O151.2390
O1—C11.3512O11—C211.3466
O1—C31.3605O11—C231.3616
O3—N71.2415O13—N151.2424
O5—N71.2322O15—N151.2390
O7—C131.2081O17—H71.7172
O9—C151.2217O17—C331.2221
O9—H231.7392O19—C351.2075
C19—C1—N7131.106C39—C21—N15131.144
C19—C1—O1111.839C39—C21—O11111.9
N7—C1—O1117.038N15—C21—O11116.955
C5—C3—C7134.101C25—C23—C27134.363
C5—C3—O1109.435C25—C23—O11109.899
C7—C3—O1116.464C27—C23—O11115.72
H13—C5—C3125.354H29—C25—C23126.248
H13—C5—C19127.272H29—C25—C39126.794
C3—C5—C19107.374C23—C25—C39106.941
H1—C7—C3116.82H17—C27—C23116.428
H1—C7—C9120.819H17—C27—C29119.78
C3—C7—C9122.356C23—C27—C29123.789
H3—C9—C7120.134H19—C29—C27121.082
H3—C9—C11116.188H19—C29—C31117.375
C7—C9—C11123.672C27—C29—C31121.539
H5—C11—C9119.676H21—C31—C29118.714
H5—C11—N1122.828H21—C31—N9122.561
C9—C11—N1117.495C29—C31—N9118.725
N3—C13—N5105.705N11—C33—N13106.558
N3—C13—O7127.975N11—C33—O17126.455
N5—C13—O7126.319N13—C33—O17126.987
C17—C15—N5106.775C37—C35—N13106.3
C17—C15—O9126.879C37—C35—O19126.98
N5—C15—O9126.346N13—C35—O19126.719
H9—C17—H11109.402H25—C37—H27108.787
H9—C17—C15110.123H25—C37—C35112.057
H11—C17—C15110.441H27—C37—C35109.642
H9—C17—N3112.349H25—C37—N11111.487
H11—C17—N3112.096H27—C37—N11112.44
C15—C17—N3102.255C35—C37—N11102.349
H15—C19—C1126.564H31—C39—C21126.816
H15—C19—C5128.088H31—C39—C25127.654
C1—C19—C5105.348C21—C39—C25105.524
C11—N1—N3118.95C31—N9—N11117.485
C13—N3—C17111.706C33—N11—C37111.818
C13—N3—N1119.565C33—N11—N9119.72
C17—N3—N1128.71C37—N11—N9128.461
H7—N5—C13122.941H23—N13—C33121.648
H7—N5—C15123.529H23—N13—C35125.396
C13—N5—C15113.529C33—N13—C35112.943
C1—N7—O3116.476C21—N15—O13116.843
C1—N7—O5118.547C21—N15—O15118.694
O3—N7—O5124.977O13—N15—O15124.462
C1—O1—C3106.003C21—O11—C23105.729
 

Follow Acta Cryst. B
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds