organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoIUCrDATA
ISSN: 2414-3146

Bis(creatininium) 3-nitro­phthalate monohydrate

aDepartment of Physics, Presidency college, Chennai 600 005, Tamil Nadu, India, and bDepartment of Physics & Nano Technology, SRM University, SRM Nagar, Kattankulathur, Kancheepuram Dist, Chennai 603 203 Tamil Nadu, India
*Correspondence e-mail: ppkpresidency@gmail.com, phdguna@gmail.com

Edited by J. Simpson, University of Otago, New Zealand (Received 24 May 2016; accepted 17 June 2016; online 24 June 2016)

In the title hydrated molecular salt, 2C4H8N3O+·C8H3NO62−·H2O, the dihedral angles between the benzene ring and the nitro group and the carboxylate groups are 48.0 (2), 55.3 (2) and 60.7 (2)°, respectively. In the crystal, the components are linked by N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds, generating a two-dimensional network parallel to (102).

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Creatinine (systematic name: 2-imino-1-methyl­imidazolidin-4-one) and its derivatives display a range of biological activity. In particular, creatinine is an indicator of renal function. In understanding renal dysfunction, the determination of creatinine is more important than that of urea (Sharma et al., 2004[Sharma, A. C., Jana, T., Kesavamoorthy, R., Shi, L., Virji, M. A., Finegold, D. N. & Asher, S. A. (2004). J. Am. Chem. Soc. 126, 2971-2977.]). Creatinine clearance is used to determine the glomerular filtration rate (GFR) of the kidneys (Mădăraş & Buck, 1996[Mădăraş, M. B. & Buck, R. P. (1996). Anal. Chem. 68, 3832-3839.]) and various disease states in biological fluids can be indicated by an abnormal level of creatinine (Narayanan & Appleton, 1980[Narayanan, S. & Appleton, H. D. (1980). Clin. Chem. 26, 1119-1126.]). We report here the structure of the proton­ated creatinine derivative bis-creatininium 3-nitro­phthalate that crystallizes as a monohydrate.

The asymmetric unit of the title compound comprises two protonated creatinine cations, one doubly deprotonated 3-nitro­phthalic acid anion and a water mol­ecule of crystallization (Fig. 1[link]). The geometric parameters of the title mol­ecule agree well with those reported for similar similar structures (Jahubar Ali et al., 2011[Jahubar Ali, A., Athimoolam, S. & Asath Bahadur, S. (2011). Acta Cryst. E67, o2905.], 2012[Jahubar Ali, A., Athimoolam, S. & Asath Bahadur, S. (2012). Acta Cryst. E68, o1285-o1286.]). The packing features N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds, which generate a two-dimensional network parallel to (102) (Table 1[link], Fig. 2[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O9W—H9WA⋯O2 0.86 (1) 1.94 (2) 2.7856 (18) 168 (2)
O9W—H9WB⋯O8i 0.85 (1) 2.16 (2) 2.9241 (18) 149 (2)
N2—H2A⋯O3ii 0.86 2.00 2.7899 (17) 152
N2—H2B⋯O2iii 0.86 1.95 2.8000 (17) 168
N3—H3A⋯O1iii 0.86 1.77 2.6275 (15) 177
N5—H5⋯O4iv 0.86 1.84 2.6836 (16) 166
N6—H6A⋯O9Wv 0.86 1.96 2.7952 (17) 163
N6—H6B⋯O3iv 0.86 1.94 2.7900 (16) 171
C4—H4⋯O5i 0.93 2.59 3.2071 (19) 124
C9—H9B⋯O6vi 0.97 2.47 3.212 (2) 133
Symmetry codes: (i) -x, -y, -z+1; (ii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iv) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x+1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (vi) -x+1, -y, -z+1.
[Figure 1]
Figure 1
The mol­ecular structure with atom labels and 30% probability displacement ellipsoids for non-H atoms.
[Figure 2]
Figure 2
The packing, viewed down the a axis. Hydrogen bonds are shown as dashed lines.

Synthesis and crystallization

Creatinine and 3-nitro­phthalic acid in 2:1 molar ratio were dissolved in deionized water. The solution was stirred well, filtered and kept in a dust-free environment. Crystals were obtained from the mother solution after 10 d (yield 95%).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula 2C4H8N3O+·C8H3NO62−·H2O
Mr 455.40
Crystal system, space group Monoclinic, P21/c
Temperature (K) 295
a, b, c (Å) 7.6682 (3), 16.5504 (6), 16.2358 (7)
β (°) 93.775 (1)
V3) 2056.04 (14)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.12
Crystal size (mm) 0.30 × 0.25 × 0.20
 
Data collection
Diffractometer Bruker APEXII CCD
Absorption correction Multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS, University of Göttingen, Germany.])
Tmin, Tmax 0.964, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections 30566, 3620, 3202
Rint 0.023
(sin θ/λ)max−1) 0.595
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.097, 1.04
No. of reflections 3620
No. of parameters 299
No. of restraints 3
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.23, −0.19
Computer programs: APEX2 and SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS97 and SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Structural data


Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Bis(2-amino-1-methyl-4-oxo-1H-imidazol-3-ium) 3-nitrobenzene-1,2-dioate monohydrate top
Crystal data top
2C4H8N3O+·C8H3NO62·H2OF(000) = 952
Mr = 455.40Dx = 1.471 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3032 reflections
a = 7.6682 (3) Åθ = 2.5–25.0°
b = 16.5504 (6) ŵ = 0.12 mm1
c = 16.2358 (7) ÅT = 295 K
β = 93.775 (1)°Block, colourless
V = 2056.04 (14) Å30.30 × 0.25 × 0.20 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
3620 independent reflections
Radiation source: fine-focus sealed tube3202 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 0 pixels mm-1θmax = 25.0°, θmin = 2.5°
ω and φ scansh = 99
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1919
Tmin = 0.964, Tmax = 0.975l = 1919
30566 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.097H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0511P)2 + 0.6212P]
where P = (Fo2 + 2Fc2)/3
3620 reflections(Δ/σ)max < 0.001
299 parametersΔρmax = 0.23 e Å3
3 restraintsΔρmin = 0.19 e Å3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O40.31739 (13)0.24338 (6)0.37689 (7)0.0426 (3)
O20.20496 (15)0.39851 (6)0.44152 (7)0.0468 (3)
O10.05094 (16)0.36012 (6)0.33692 (7)0.0500 (3)
O70.12906 (18)0.00022 (8)0.32383 (8)0.0623 (4)
O30.26695 (14)0.34371 (6)0.46389 (7)0.0455 (3)
O80.37908 (18)0.23485 (8)0.30455 (8)0.0650 (4)
N40.04747 (17)0.14441 (7)0.19650 (8)0.0411 (3)
N50.50199 (16)0.15212 (7)0.21091 (8)0.0382 (3)
H50.54310.18820.17940.046*
C10.09432 (17)0.26573 (8)0.44182 (8)0.0292 (3)
C50.08351 (17)0.15554 (8)0.48841 (8)0.0306 (3)
O60.36494 (17)0.16305 (9)0.54522 (9)0.0698 (4)
N10.25658 (17)0.12099 (8)0.50719 (9)0.0455 (3)
N70.43615 (16)0.03075 (8)0.25712 (7)0.0392 (3)
N20.15811 (18)0.06240 (8)0.09368 (8)0.0446 (3)
H2A0.19820.10280.06750.054*
H2B0.17110.01410.07550.054*
C60.07245 (17)0.23258 (7)0.45540 (7)0.0275 (3)
N60.59974 (16)0.04045 (7)0.13985 (8)0.0406 (3)
H6A0.60650.01110.13430.049*
H6B0.64790.07180.10570.049*
N30.01716 (15)0.01224 (7)0.20550 (7)0.0367 (3)
H3A0.02750.03800.19320.044*
O50.28472 (18)0.05264 (8)0.48399 (11)0.0811 (5)
C20.24056 (18)0.22093 (9)0.45977 (9)0.0357 (3)
H20.35120.24360.45130.043*
C140.07773 (18)0.07435 (8)0.16086 (8)0.0341 (3)
C40.05969 (19)0.11000 (8)0.50609 (9)0.0364 (3)
H40.04640.05840.52820.044*
C80.23328 (17)0.27727 (8)0.43044 (8)0.0314 (3)
C30.22333 (19)0.14322 (9)0.49004 (9)0.0387 (3)
H30.32240.11320.49970.046*
C70.11757 (18)0.34859 (8)0.40421 (9)0.0338 (3)
C90.3674 (2)0.08763 (10)0.31486 (9)0.0468 (4)
H9A0.24200.08150.31720.056*
H9B0.42290.08070.36980.056*
C110.51691 (17)0.07093 (8)0.19967 (8)0.0333 (3)
C100.4126 (2)0.16844 (10)0.27923 (10)0.0445 (4)
C130.0626 (2)0.04049 (10)0.27279 (9)0.0423 (4)
C150.4564 (2)0.05471 (10)0.27549 (11)0.0492 (4)
H15A0.55080.06210.31660.074*
H15B0.35020.07520.29580.074*
H15C0.48140.08330.22620.074*
C120.0482 (2)0.13135 (10)0.26946 (10)0.0480 (4)
H12A0.16270.15640.26380.058*
H12B0.01550.15240.31850.058*
C160.0946 (3)0.22366 (10)0.16828 (11)0.0602 (5)
H16A0.19490.21950.13610.090*
H16B0.12170.25800.21500.090*
H16C0.00130.24620.13490.090*
O9W0.3299 (2)0.38052 (7)0.59774 (8)0.0656 (4)
H9WA0.302 (3)0.3802 (13)0.5476 (7)0.090 (8)*
H9WB0.358 (3)0.3319 (8)0.6078 (13)0.100 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O40.0439 (6)0.0355 (5)0.0506 (6)0.0020 (4)0.0200 (5)0.0028 (5)
O20.0563 (7)0.0333 (6)0.0528 (6)0.0121 (5)0.0187 (5)0.0086 (5)
O10.0735 (8)0.0375 (6)0.0411 (6)0.0100 (5)0.0192 (5)0.0112 (5)
O70.0802 (9)0.0622 (8)0.0472 (7)0.0035 (7)0.0254 (6)0.0062 (6)
O30.0558 (7)0.0379 (6)0.0445 (6)0.0188 (5)0.0165 (5)0.0095 (5)
O80.0799 (9)0.0548 (8)0.0619 (8)0.0041 (6)0.0164 (7)0.0222 (6)
N40.0553 (8)0.0328 (6)0.0353 (7)0.0030 (5)0.0038 (6)0.0046 (5)
N50.0414 (7)0.0341 (7)0.0400 (7)0.0036 (5)0.0093 (5)0.0023 (5)
C10.0342 (7)0.0271 (7)0.0267 (6)0.0014 (5)0.0042 (5)0.0002 (5)
C50.0335 (7)0.0272 (7)0.0317 (7)0.0031 (5)0.0064 (5)0.0003 (5)
O60.0455 (7)0.0771 (9)0.0840 (10)0.0088 (7)0.0164 (7)0.0045 (8)
N10.0419 (7)0.0367 (7)0.0590 (8)0.0083 (6)0.0114 (6)0.0131 (6)
N70.0424 (7)0.0408 (7)0.0352 (6)0.0059 (5)0.0086 (5)0.0018 (5)
N20.0640 (9)0.0340 (7)0.0374 (7)0.0006 (6)0.0153 (6)0.0025 (5)
C60.0337 (7)0.0244 (6)0.0247 (6)0.0016 (5)0.0049 (5)0.0023 (5)
N60.0464 (7)0.0322 (6)0.0452 (7)0.0007 (5)0.0177 (6)0.0027 (5)
N30.0438 (7)0.0333 (6)0.0334 (6)0.0011 (5)0.0052 (5)0.0034 (5)
O50.0613 (8)0.0378 (7)0.1471 (15)0.0172 (6)0.0299 (9)0.0047 (8)
C20.0308 (7)0.0379 (8)0.0388 (8)0.0019 (6)0.0050 (6)0.0017 (6)
C140.0377 (7)0.0343 (7)0.0298 (7)0.0011 (6)0.0026 (6)0.0021 (6)
C40.0458 (8)0.0231 (6)0.0418 (8)0.0001 (6)0.0133 (6)0.0031 (6)
C80.0330 (7)0.0298 (7)0.0317 (7)0.0012 (5)0.0037 (5)0.0018 (5)
C30.0374 (8)0.0354 (8)0.0445 (8)0.0078 (6)0.0130 (6)0.0005 (6)
C70.0357 (7)0.0311 (7)0.0344 (7)0.0015 (6)0.0023 (6)0.0048 (6)
C90.0486 (9)0.0593 (10)0.0334 (8)0.0110 (8)0.0093 (7)0.0081 (7)
C110.0293 (7)0.0360 (7)0.0347 (7)0.0029 (5)0.0020 (5)0.0006 (6)
C100.0438 (9)0.0494 (9)0.0404 (8)0.0025 (7)0.0039 (7)0.0123 (7)
C130.0460 (8)0.0488 (9)0.0322 (8)0.0065 (7)0.0036 (6)0.0006 (7)
C150.0487 (9)0.0476 (9)0.0517 (9)0.0067 (7)0.0064 (7)0.0135 (8)
C120.0629 (10)0.0468 (9)0.0350 (8)0.0098 (8)0.0073 (7)0.0077 (7)
C160.0952 (15)0.0345 (9)0.0512 (10)0.0020 (9)0.0069 (9)0.0022 (7)
O9W0.1076 (11)0.0374 (7)0.0546 (8)0.0013 (7)0.0266 (8)0.0016 (6)
Geometric parameters (Å, º) top
O4—C81.2491 (16)C6—C81.5159 (18)
O2—C71.2458 (17)N6—C111.2970 (18)
O1—C71.2508 (17)N6—H6A0.8600
O7—C131.2065 (19)N6—H6B0.8600
O3—C81.2459 (17)N3—C141.3573 (19)
O8—C101.2072 (19)N3—C131.3690 (19)
N4—C141.3232 (18)N3—H3A0.8600
N4—C161.443 (2)C2—C31.380 (2)
N4—C121.450 (2)C2—H20.9300
N5—C111.3617 (18)C4—C31.379 (2)
N5—C101.369 (2)C4—H40.9300
N5—H50.8600C3—H30.9300
C1—C21.3911 (19)C9—C101.507 (2)
C1—C61.3957 (18)C9—H9A0.9700
C1—C71.5070 (18)C9—H9B0.9700
C5—C41.3775 (19)C13—C121.509 (2)
C5—C61.3836 (18)C15—H15A0.9600
C5—N11.4587 (18)C15—H15B0.9600
O6—N11.2200 (19)C15—H15C0.9600
N1—O51.2161 (18)C12—H12A0.9700
N7—C111.3311 (18)C12—H12B0.9700
N7—C151.452 (2)C16—H16A0.9600
N7—C91.452 (2)C16—H16B0.9600
N2—C141.3028 (19)C16—H16C0.9600
N2—H2A0.8600O9W—H9WA0.855 (9)
N2—H2B0.8600O9W—H9WB0.852 (9)
C14—N4—C16127.06 (14)O4—C8—C6115.68 (12)
C14—N4—C12109.84 (12)C4—C3—C2120.23 (13)
C16—N4—C12123.07 (13)C4—C3—H3119.9
C11—N5—C10110.75 (12)C2—C3—H3119.9
C11—N5—H5124.6O2—C7—O1125.96 (13)
C10—N5—H5124.6O2—C7—C1117.35 (12)
C2—C1—C6120.02 (12)O1—C7—C1116.65 (12)
C2—C1—C7119.63 (12)N7—C9—C10103.02 (12)
C6—C1—C7120.29 (11)N7—C9—H9A111.2
C4—C5—C6123.75 (12)C10—C9—H9A111.2
C4—C5—N1117.95 (12)N7—C9—H9B111.2
C6—C5—N1118.29 (12)C10—C9—H9B111.2
O5—N1—O6123.96 (15)H9A—C9—H9B109.1
O5—N1—C5118.51 (14)N6—C11—N7127.13 (13)
O6—N1—C5117.52 (13)N6—C11—N5122.26 (13)
C11—N7—C15125.62 (13)N7—C11—N5110.61 (12)
C11—N7—C9109.51 (12)O8—C10—N5125.80 (16)
C15—N7—C9122.51 (13)O8—C10—C9128.18 (15)
C14—N2—H2A120.0N5—C10—C9106.03 (13)
C14—N2—H2B120.0O7—C13—N3126.04 (15)
H2A—N2—H2B120.0O7—C13—C12128.05 (14)
C5—C6—C1117.10 (12)N3—C13—C12105.90 (13)
C5—C6—C8121.54 (12)N7—C15—H15A109.5
C1—C6—C8121.27 (11)N7—C15—H15B109.5
C11—N6—H6A120.0H15A—C15—H15B109.5
C11—N6—H6B120.0N7—C15—H15C109.5
H6A—N6—H6B120.0H15A—C15—H15C109.5
C14—N3—C13110.74 (12)H15B—C15—H15C109.5
C14—N3—H3A124.6N4—C12—C13102.71 (12)
C13—N3—H3A124.6N4—C12—H12A111.2
C3—C2—C1120.78 (13)C13—C12—H12A111.2
C3—C2—H2119.6N4—C12—H12B111.2
C1—C2—H2119.6C13—C12—H12B111.2
N2—C14—N4127.26 (14)H12A—C12—H12B109.1
N2—C14—N3121.98 (13)N4—C16—H16A109.5
N4—C14—N3110.74 (12)N4—C16—H16B109.5
C5—C4—C3118.06 (12)H16A—C16—H16B109.5
C5—C4—H4121.0N4—C16—H16C109.5
C3—C4—H4121.0H16A—C16—H16C109.5
O3—C8—O4126.73 (13)H16B—C16—H16C109.5
O3—C8—C6117.58 (12)H9WA—O9W—H9WB105.1 (14)
C4—C5—N1—O549.1 (2)C1—C6—C8—O4117.14 (14)
C6—C5—N1—O5132.09 (15)C5—C4—C3—C22.1 (2)
C4—C5—N1—O6131.17 (15)C1—C2—C3—C42.6 (2)
C6—C5—N1—O647.61 (19)C2—C1—C7—O255.03 (18)
C4—C5—C6—C11.80 (19)C6—C1—C7—O2127.68 (14)
N1—C5—C6—C1176.91 (12)C2—C1—C7—O1123.06 (15)
C4—C5—C6—C8174.78 (13)C6—C1—C7—O154.23 (18)
N1—C5—C6—C86.51 (19)C11—N7—C9—C102.97 (16)
C2—C1—C6—C51.31 (19)C15—N7—C9—C10166.41 (14)
C7—C1—C6—C5178.58 (12)C15—N7—C11—N614.4 (2)
C2—C1—C6—C8175.28 (12)C9—N7—C11—N6177.21 (14)
C7—C1—C6—C82.00 (18)C15—N7—C11—N5165.78 (14)
C6—C1—C2—C30.8 (2)C9—N7—C11—N52.98 (16)
C7—C1—C2—C3176.46 (13)C10—N5—C11—N6178.51 (13)
C16—N4—C14—N21.0 (3)C10—N5—C11—N71.67 (17)
C12—N4—C14—N2179.12 (15)C11—N5—C10—O8179.93 (16)
C16—N4—C14—N3179.08 (16)C11—N5—C10—C90.30 (17)
C12—N4—C14—N32.76 (17)N7—C9—C10—O8178.31 (17)
C13—N3—C14—N2179.73 (14)N7—C9—C10—N51.93 (16)
C13—N3—C14—N42.03 (16)C14—N3—C13—O7179.98 (16)
C6—C5—C4—C30.1 (2)C14—N3—C13—C120.45 (16)
N1—C5—C4—C3178.63 (13)C14—N4—C12—C132.32 (17)
C5—C6—C8—O3121.68 (14)C16—N4—C12—C13179.43 (15)
C1—C6—C8—O361.89 (17)O7—C13—C12—N4178.47 (16)
C5—C6—C8—O459.29 (17)N3—C13—C12—N41.08 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O9W—H9WA···O20.86 (1)1.94 (2)2.7856 (18)168 (2)
O9W—H9WB···O8i0.85 (1)2.16 (2)2.9241 (18)149 (2)
N2—H2A···O3ii0.862.002.7899 (17)152
N2—H2B···O2iii0.861.952.8000 (17)168
N3—H3A···O1iii0.861.772.6275 (15)177
N5—H5···O4iv0.861.842.6836 (16)166
N6—H6A···O9Wv0.861.962.7952 (17)163
N6—H6B···O3iv0.861.942.7900 (16)171
C4—H4···O5i0.932.593.2071 (19)124
C9—H9B···O6vi0.972.473.212 (2)133
Symmetry codes: (i) x, y, z+1; (ii) x, y+1/2, z1/2; (iii) x, y1/2, z+1/2; (iv) x+1, y1/2, z+1/2; (v) x+1, y+1/2, z1/2; (vi) x+1, y, z+1.
 

References

First citationBruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationJahubar Ali, A., Athimoolam, S. & Asath Bahadur, S. (2011). Acta Cryst. E67, o2905.  CSD CrossRef IUCr Journals Google Scholar
First citationJahubar Ali, A., Athimoolam, S. & Asath Bahadur, S. (2012). Acta Cryst. E68, o1285–o1286.  CSD CrossRef IUCr Journals Google Scholar
First citationMădăraş, M. B. & Buck, R. P. (1996). Anal. Chem. 68, 3832–3839.  PubMed Google Scholar
First citationNarayanan, S. & Appleton, H. D. (1980). Clin. Chem. 26, 1119–1126.  CAS PubMed Web of Science Google Scholar
First citationSharma, A. C., Jana, T., Kesavamoorthy, R., Shi, L., Virji, M. A., Finegold, D. N. & Asher, S. A. (2004). J. Am. Chem. Soc. 126, 2971–2977.  Web of Science CrossRef PubMed CAS Google Scholar
First citationSheldrick, G. M. (1996). SADABS, University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoIUCrDATA
ISSN: 2414-3146
Follow IUCr Journals
Sign up for e-alerts
Follow IUCr on Twitter
Follow us on facebook
Sign up for RSS feeds