organic compounds
rac-7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic acid–2-amino-1,3,4-thiadiazole–water (1/1/1)
aZhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, People's Republic of China, and, College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, Zhejiang, People's Republic of China
*Correspondence e-mail: sky51@zjnu.cn
The title compound, C8H10O5·C2H3N3S·H2O, was synthesized by the reaction of 2-amino-1,3,4-thiadiazole with norcantharidin. The is stabilized by N—H⋯O, N—H⋯N, O—H⋯O and O—H⋯N hydrogen bonds. In addition, weak π–π interactions are observed between symmetry-related thiadiazole ring systems [centroid–centroid distance = 3.9110 (3) Å, interplanar spacing = 3.4845 Å].
Related literature
7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin) is a lower toxicity anticancer drug, see: Shimi & Zaki (1982).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2006); cell SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536809021825/at2800sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809021825/at2800Isup2.hkl
7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride and 2-amino-1,3,4-thiadiazole were dissolved in tetrahydrofuran and the mixture was stirred for 6 h at room temperature. The clear solution was left undisturbed for days to give colourless crystals of the compound.
The H atoms bonded to C and N atoms were positioned geometrically and refined using ariding model [C—H =0.93- 0.98 Å, N—H = 0.86 Å and O—H = 0.82 Å and Uiso(H) = 1.2 or 1.5Ueq(C,N,O)]. The H atoms of the water molecule were located in a difference Fourier maps and refined with O—H distance restraints of 0.85 (2) and Uiso(H) = 1.5Ueq(O).
Data collection: APEX2 (Bruker, 2006); cell
SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. A view of the molecule of (I) showing the atom-labelling scheme with displacement ellipsoids drawn at the 30% probability. |
C8H10O5·C2H3N3S·H2O | F(000) = 640 |
Mr = 305.31 | Dx = 1.526 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 1905 reflections |
a = 5.7678 (5) Å | θ = 2.0–27.6° |
b = 18.4267 (15) Å | µ = 0.27 mm−1 |
c = 12.7546 (11) Å | T = 296 K |
β = 101.336 (6)° | Block, colourless |
V = 1329.1 (2) Å3 | 0.30 × 0.16 × 0.09 mm |
Z = 4 |
Bruker APEXII area-detector diffractometer | 2995 independent reflections |
Radiation source: fine-focus sealed tube | 2026 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.040 |
ω scans | θmax = 27.6°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −6→7 |
Tmin = 0.949, Tmax = 0.977 | k = −24→23 |
10820 measured reflections | l = −16→15 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.046 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.133 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.062P)2 + 0.3174P] where P = (Fo2 + 2Fc2)/3 |
2995 reflections | (Δ/σ)max = 0.001 |
187 parameters | Δρmax = 0.30 e Å−3 |
3 restraints | Δρmin = −0.29 e Å−3 |
C8H10O5·C2H3N3S·H2O | V = 1329.1 (2) Å3 |
Mr = 305.31 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 5.7678 (5) Å | µ = 0.27 mm−1 |
b = 18.4267 (15) Å | T = 296 K |
c = 12.7546 (11) Å | 0.30 × 0.16 × 0.09 mm |
β = 101.336 (6)° |
Bruker APEXII area-detector diffractometer | 2995 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2026 reflections with I > 2σ(I) |
Tmin = 0.949, Tmax = 0.977 | Rint = 0.040 |
10820 measured reflections |
R[F2 > 2σ(F2)] = 0.046 | 3 restraints |
wR(F2) = 0.133 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.30 e Å−3 |
2995 reflections | Δρmin = −0.29 e Å−3 |
187 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
C1 | −0.2976 (5) | 0.05357 (14) | 0.3265 (2) | 0.0537 (7) | |
H1B | −0.3880 | 0.0947 | 0.3053 | 0.064* | |
C2 | −0.0094 (4) | −0.03835 (13) | 0.37115 (19) | 0.0401 (6) | |
C3 | −0.7049 (4) | −0.14263 (12) | −0.02775 (19) | 0.0371 (5) | |
H3A | −0.7478 | −0.1570 | −0.1031 | 0.044* | |
C4 | −0.4729 (4) | −0.10527 (12) | 0.11367 (19) | 0.0378 (5) | |
H4A | −0.3228 | −0.0881 | 0.1563 | 0.045* | |
C5 | −0.5597 (4) | −0.17663 (11) | 0.15371 (18) | 0.0308 (5) | |
H5A | −0.6555 | −0.1649 | 0.2069 | 0.037* | |
C6 | −0.7289 (4) | −0.20482 (11) | 0.05131 (18) | 0.0320 (5) | |
H6A | −0.8916 | −0.2080 | 0.0630 | 0.038* | |
C7 | −0.8388 (4) | −0.07593 (13) | −0.0002 (2) | 0.0436 (6) | |
H7A | −0.9932 | −0.0888 | 0.0135 | 0.052* | |
H7B | −0.8573 | −0.0399 | −0.0566 | 0.052* | |
C8 | −0.6732 (4) | −0.04919 (12) | 0.1016 (2) | 0.0451 (6) | |
H8A | −0.7506 | −0.0499 | 0.1626 | 0.054* | |
H8B | −0.6158 | −0.0006 | 0.0925 | 0.054* | |
C9 | −0.3734 (4) | −0.23059 (12) | 0.20304 (18) | 0.0339 (5) | |
C10 | −0.6556 (4) | −0.27519 (12) | 0.00717 (19) | 0.0357 (5) | |
S1 | −0.00230 (12) | 0.04890 (3) | 0.32282 (6) | 0.0514 (2) | |
N1 | 0.1766 (3) | −0.08184 (12) | 0.39063 (18) | 0.0534 (6) | |
H1A | 0.1631 | −0.1250 | 0.4145 | 0.064* | |
H1C | 0.3110 | −0.0670 | 0.3794 | 0.064* | |
N2 | −0.2197 (3) | −0.05840 (10) | 0.38689 (17) | 0.0431 (5) | |
N3 | −0.3854 (4) | −0.00394 (11) | 0.36078 (19) | 0.0511 (6) | |
O1 | −0.4621 (3) | −0.12182 (8) | 0.00484 (13) | 0.0399 (4) | |
O1W | 0.3491 (3) | 0.19399 (12) | 0.19534 (16) | 0.0573 (5) | |
O2 | −0.1540 (3) | −0.20904 (9) | 0.21051 (15) | 0.0470 (5) | |
H2A | −0.0641 | −0.2405 | 0.2405 | 0.071* | |
O3 | −0.4251 (3) | −0.28854 (9) | 0.23715 (14) | 0.0453 (4) | |
O4 | −0.4568 (3) | −0.28772 (9) | −0.00388 (16) | 0.0527 (5) | |
O5 | −0.8343 (3) | −0.31955 (9) | −0.02355 (17) | 0.0575 (5) | |
H5B | −0.7870 | −0.3568 | −0.0474 | 0.086* | |
H1WA | 0.213 (4) | 0.1986 (18) | 0.212 (2) | 0.086* | |
H1WB | 0.317 (5) | 0.2024 (19) | 0.1311 (15) | 0.086* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0577 (16) | 0.0398 (14) | 0.064 (2) | 0.0017 (11) | 0.0119 (14) | 0.0069 (13) |
C2 | 0.0431 (13) | 0.0412 (13) | 0.0358 (14) | −0.0098 (10) | 0.0075 (10) | −0.0022 (10) |
C3 | 0.0419 (13) | 0.0369 (12) | 0.0311 (13) | 0.0077 (9) | 0.0038 (10) | −0.0009 (10) |
C4 | 0.0383 (12) | 0.0342 (12) | 0.0394 (14) | −0.0035 (9) | 0.0041 (10) | 0.0000 (10) |
C5 | 0.0310 (11) | 0.0334 (11) | 0.0289 (12) | 0.0019 (8) | 0.0081 (9) | 0.0004 (9) |
C6 | 0.0280 (11) | 0.0316 (11) | 0.0371 (14) | 0.0013 (8) | 0.0081 (9) | −0.0036 (9) |
C7 | 0.0443 (13) | 0.0368 (12) | 0.0486 (16) | 0.0118 (10) | 0.0062 (11) | 0.0015 (11) |
C8 | 0.0606 (16) | 0.0306 (12) | 0.0448 (16) | 0.0032 (10) | 0.0119 (12) | −0.0033 (11) |
C9 | 0.0339 (12) | 0.0390 (12) | 0.0300 (13) | 0.0015 (9) | 0.0094 (9) | −0.0002 (10) |
C10 | 0.0366 (13) | 0.0334 (12) | 0.0365 (14) | 0.0016 (9) | 0.0058 (10) | −0.0027 (9) |
S1 | 0.0575 (4) | 0.0399 (4) | 0.0583 (5) | −0.0095 (3) | 0.0150 (3) | 0.0073 (3) |
N1 | 0.0475 (12) | 0.0419 (12) | 0.0697 (17) | −0.0015 (9) | 0.0089 (11) | 0.0107 (11) |
N2 | 0.0455 (11) | 0.0354 (10) | 0.0480 (13) | −0.0044 (8) | 0.0085 (9) | 0.0048 (9) |
N3 | 0.0462 (12) | 0.0434 (12) | 0.0625 (15) | 0.0023 (9) | 0.0083 (11) | 0.0072 (11) |
O1 | 0.0417 (9) | 0.0391 (9) | 0.0425 (10) | 0.0032 (7) | 0.0170 (7) | 0.0082 (7) |
O1W | 0.0381 (10) | 0.0837 (14) | 0.0524 (12) | −0.0079 (9) | 0.0140 (9) | −0.0121 (11) |
O2 | 0.0315 (9) | 0.0499 (10) | 0.0589 (12) | 0.0004 (7) | 0.0068 (8) | 0.0103 (8) |
O3 | 0.0374 (9) | 0.0435 (9) | 0.0558 (12) | 0.0049 (7) | 0.0108 (8) | 0.0171 (8) |
O4 | 0.0406 (10) | 0.0447 (10) | 0.0747 (14) | 0.0032 (7) | 0.0163 (9) | −0.0214 (9) |
O5 | 0.0411 (10) | 0.0362 (9) | 0.0954 (16) | −0.0057 (7) | 0.0137 (9) | −0.0213 (10) |
C1—N3 | 1.287 (3) | C6—H6A | 0.9800 |
C1—S1 | 1.715 (3) | C7—C8 | 1.534 (3) |
C1—H1B | 0.9300 | C7—H7A | 0.9700 |
C2—N2 | 1.320 (3) | C7—H7B | 0.9700 |
C2—N1 | 1.323 (3) | C8—H8A | 0.9700 |
C2—S1 | 1.725 (2) | C8—H8B | 0.9700 |
C3—O1 | 1.433 (3) | C9—O3 | 1.212 (3) |
C3—C7 | 1.529 (3) | C9—O2 | 1.311 (3) |
C3—C6 | 1.550 (3) | C10—O4 | 1.205 (3) |
C3—H3A | 0.9800 | C10—O5 | 1.313 (3) |
C4—O1 | 1.434 (3) | N1—H1A | 0.8600 |
C4—C5 | 1.530 (3) | N1—H1C | 0.8600 |
C4—C8 | 1.535 (3) | N2—N3 | 1.381 (3) |
C4—H4A | 0.9800 | O1W—H1WA | 0.859 (17) |
C5—C9 | 1.508 (3) | O1W—H1WB | 0.819 (17) |
C5—C6 | 1.558 (3) | O2—H2A | 0.8200 |
C5—H5A | 0.9800 | O5—H5B | 0.8200 |
C6—C10 | 1.507 (3) | ||
N3—C1—S1 | 115.3 (2) | C5—C6—H6A | 110.7 |
N3—C1—H1B | 122.4 | C3—C7—C8 | 101.18 (17) |
S1—C1—H1B | 122.4 | C3—C7—H7A | 111.5 |
N2—C2—N1 | 122.5 (2) | C8—C7—H7A | 111.5 |
N2—C2—S1 | 113.71 (18) | C3—C7—H7B | 111.5 |
N1—C2—S1 | 123.80 (18) | C8—C7—H7B | 111.5 |
O1—C3—C7 | 103.14 (18) | H7A—C7—H7B | 109.4 |
O1—C3—C6 | 102.49 (17) | C7—C8—C4 | 101.53 (18) |
C7—C3—C6 | 109.34 (19) | C7—C8—H8A | 111.5 |
O1—C3—H3A | 113.6 | C4—C8—H8A | 111.5 |
C7—C3—H3A | 113.6 | C7—C8—H8B | 111.5 |
C6—C3—H3A | 113.6 | C4—C8—H8B | 111.5 |
O1—C4—C5 | 102.67 (17) | H8A—C8—H8B | 109.3 |
O1—C4—C8 | 102.77 (18) | O3—C9—O2 | 122.9 (2) |
C5—C4—C8 | 108.84 (18) | O3—C9—C5 | 121.68 (19) |
O1—C4—H4A | 113.8 | O2—C9—C5 | 115.39 (19) |
C5—C4—H4A | 113.8 | O4—C10—O5 | 123.7 (2) |
C8—C4—H4A | 113.8 | O4—C10—C6 | 123.5 (2) |
C9—C5—C4 | 116.94 (17) | O5—C10—C6 | 112.67 (18) |
C9—C5—C6 | 114.05 (17) | C1—S1—C2 | 86.76 (12) |
C4—C5—C6 | 101.48 (17) | C2—N1—H1A | 120.0 |
C9—C5—H5A | 108.0 | C2—N1—H1C | 120.0 |
C4—C5—H5A | 108.0 | H1A—N1—H1C | 120.0 |
C6—C5—H5A | 108.0 | C2—N2—N3 | 111.89 (19) |
C10—C6—C3 | 108.99 (18) | C1—N3—N2 | 112.4 (2) |
C10—C6—C5 | 115.12 (17) | C3—O1—C4 | 96.42 (15) |
C3—C6—C5 | 100.22 (17) | H1WA—O1W—H1WB | 101 (2) |
C10—C6—H6A | 110.7 | C9—O2—H2A | 109.5 |
C3—C6—H6A | 110.7 | C10—O5—H5B | 109.5 |
O1—C4—C5—C9 | 90.1 (2) | C6—C5—C9—O3 | −62.0 (3) |
C8—C4—C5—C9 | −161.49 (19) | C4—C5—C9—O2 | 2.8 (3) |
O1—C4—C5—C6 | −34.65 (19) | C6—C5—C9—O2 | 120.9 (2) |
C8—C4—C5—C6 | 73.8 (2) | C3—C6—C10—O4 | 65.8 (3) |
O1—C3—C6—C10 | −86.2 (2) | C5—C6—C10—O4 | −45.8 (3) |
C7—C3—C6—C10 | 164.91 (18) | C3—C6—C10—O5 | −110.5 (2) |
O1—C3—C6—C5 | 35.06 (19) | C5—C6—C10—O5 | 137.9 (2) |
C7—C3—C6—C5 | −73.9 (2) | N3—C1—S1—C2 | 0.4 (2) |
C9—C5—C6—C10 | −10.1 (3) | N2—C2—S1—C1 | −0.1 (2) |
C4—C5—C6—C10 | 116.51 (19) | N1—C2—S1—C1 | 179.7 (2) |
C9—C5—C6—C3 | −126.86 (18) | N1—C2—N2—N3 | −179.9 (2) |
C4—C5—C6—C3 | −0.22 (19) | S1—C2—N2—N3 | −0.1 (3) |
O1—C3—C7—C8 | −34.6 (2) | S1—C1—N3—N2 | −0.5 (3) |
C6—C3—C7—C8 | 73.9 (2) | C2—N2—N3—C1 | 0.4 (3) |
C3—C7—C8—C4 | 0.3 (2) | C7—C3—O1—C4 | 56.17 (19) |
O1—C4—C8—C7 | 33.9 (2) | C6—C3—O1—C4 | −57.40 (18) |
C5—C4—C8—C7 | −74.5 (2) | C5—C4—O1—C3 | 57.35 (18) |
C4—C5—C9—O3 | 179.9 (2) | C8—C4—O1—C3 | −55.63 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O4i | 0.86 | 2.11 | 2.930 (3) | 160 |
N1—H1C···N3ii | 0.86 | 2.15 | 2.994 (3) | 166 |
N1—H1C···N2ii | 0.86 | 2.69 | 3.519 (3) | 161 |
O2—H2A···O1Wiii | 0.82 | 1.81 | 2.626 (2) | 176 |
O5—H5B···N2iv | 0.82 | 1.85 | 2.664 (2) | 172 |
O1W—H1WA···O3v | 0.86 (2) | 1.91 (2) | 2.766 (2) | 175 (3) |
O1W—H1WB···O4vi | 0.82 (2) | 2.51 (3) | 3.151 (3) | 137 (3) |
O1W—H1WB···O1vi | 0.82 (2) | 2.55 (3) | 3.061 (3) | 122 (3) |
Symmetry codes: (i) x+1/2, −y−1/2, z+1/2; (ii) x+1, y, z; (iii) −x+1/2, y−1/2, −z+1/2; (iv) x−1/2, −y−1/2, z−1/2; (v) −x−1/2, y+1/2, −z+1/2; (vi) −x, −y, −z. |
Experimental details
Crystal data | |
Chemical formula | C8H10O5·C2H3N3S·H2O |
Mr | 305.31 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 296 |
a, b, c (Å) | 5.7678 (5), 18.4267 (15), 12.7546 (11) |
β (°) | 101.336 (6) |
V (Å3) | 1329.1 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.27 |
Crystal size (mm) | 0.30 × 0.16 × 0.09 |
Data collection | |
Diffractometer | Bruker APEXII area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.949, 0.977 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10820, 2995, 2026 |
Rint | 0.040 |
(sin θ/λ)max (Å−1) | 0.653 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.046, 0.133, 1.05 |
No. of reflections | 2995 |
No. of parameters | 187 |
No. of restraints | 3 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.30, −0.29 |
Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O4i | 0.86 | 2.11 | 2.930 (3) | 160.4 |
N1—H1C···N3ii | 0.86 | 2.15 | 2.994 (3) | 165.8 |
N1—H1C···N2ii | 0.86 | 2.69 | 3.519 (3) | 160.9 |
O2—H2A···O1Wiii | 0.82 | 1.81 | 2.626 (2) | 176.1 |
O5—H5B···N2iv | 0.82 | 1.85 | 2.664 (2) | 172.3 |
O1W—H1WA···O3v | 0.859 (17) | 1.910 (17) | 2.766 (2) | 175 (3) |
O1W—H1WB···O4vi | 0.819 (17) | 2.51 (3) | 3.151 (3) | 137 (3) |
O1W—H1WB···O1vi | 0.819 (17) | 2.55 (3) | 3.061 (3) | 122 (3) |
Symmetry codes: (i) x+1/2, −y−1/2, z+1/2; (ii) x+1, y, z; (iii) −x+1/2, y−1/2, −z+1/2; (iv) x−1/2, −y−1/2, z−1/2; (v) −x−1/2, y+1/2, −z+1/2; (vi) −x, −y, −z. |
Acknowledgements
The authors thank the Natural Science Foundation of Zhejiang Province, China (grant No. Y407301) for financial support.
References
Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Shimi, I. R. & Zaki, Z. (1982). Eur. J. Cancer Clin. Oncol. 18, 785–793. CrossRef CAS PubMed Web of Science Google Scholar
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7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin) derived from cantharidin is a lower toxicity anticancer drug (Shimi & Zaki, 1982). The title compound was synthesized by the reaction of 2-amino-1,3,4-thiadiazole with 7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin). In this paper, we reports its structure.
X-ray crystallography measurement confirmed the molecular structure and the atom connectivity for the title compound (Fig. 1). The crystal structure is stabilized by N—H···O, N—H···N, O—H···O and O—H···N hydrogen bonds (Table 1). Further, weak π–π interactions are observed between symmetry related thiadiazole ring systems [centroid-centroid distance of 3.9110 (3)Å and interplanar spacing of 3.4845 Å].