

Supporting information
![]() | Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807021484/sj2311sup1.cif |
![]() | Structure factor file (CIF format) https://doi.org/10.1107/S1600536807021484/sj2311Isup2.hkl |
CCDC reference: 651400
To a suspension of ethyl 1-((2-chlorothiazol-5-yl)methyl)- 5-((isobutylamino)(phenyl)methyleneamino)-1H-1,2,3-triazole-4-carboxylate (0.92 g, 2 mmol) in 10 ml of anhydrous ethanol, several drops of EtONa in EtOH were added at room temperature. The mixture was stirred for 10 min (monitored by thin layer chromatography), then the solution concentrated under vacuum and the residue was recrystallized from dichloromethane to give the title compound (yield 76%). Colourless crystals of (I) suitable for X-ray structure analysis were grown from a mixture of dichloromethane and ethanol (v/v, 1:3).
All H atoms were placed in calculated positions, with C—H distances in the range 0.93–0.97 Å and N—H distances of 0.77–0.88 Å, and included in the final cycles of refinement using a riding-model approximation, with Uiso(H) = 1.2–1.5Ueq(carrier atom).
8-aza analogues of similarly substituted purines ([1,2,3]triazolo[4,5-d]pyrimidines are one such example) have been synthesized in recent years, and many of them exhibit broad spectral biological activities, such as the interesting antifungal (Roblin et al., 1945), antiviral (Shealy et al., 1984), anticancer (Kidder et al., 1951) and antiallergic (Lunt, 1982) activities. Recently, we have developed a versatile method via tandem aza-Wittig, followed by the cyclization to synthesize the novel triazolo[4,5-d]-pyrimidine derivatives (Ding et al., 2004; Wang et al., 2004). In this paper, we report the structure of the title compound, (I) (Fig. 1). In the triazolopyrimidine ring, the C5—N2, C5—N6, C6—N4, C7—N5 and C8—N5 bonds, Tabel 1, are significantly shorter than a normal single C—N bond (1.47 Å; Sasada, 1984) and closer to the value for a C═N bond (1.28 Å; Wang et al., 1998). This indicates significant electron delocalization in the triazolo[4,5-d]pyrimidinyl system.
In the crystal structure, intermolecular N—H···N hydrogen-bonds contribute strongly to the stability of the molecular configuration (Fig.2 and Table 1). In addition, short intermolecular distances between the centroids of the C1–C2/N1/S1 ring (Cg1) and the C13–C18 ring (Cg4) of the adjacent molecule indicate the existence of weak π— π stacking interactions [Cg1···Cg4i =3.7237 (20) Å, dihedral angles of 5.94 (16)°, and a shortest interplanar distance of 3.388 Å.; symmetry code: (i) 1/2 + x, -1/2 + y, z.
For biological activities of 8-aza purines, see: Roblin et al. (1945); Shealy et al. (1984); Kidder et al. (1951); Lunt (1982). For the synthesis of triazolopyrimidine compounds, see: Ding et al. (2004); Wang et al. (2004).
For related literature, see: Sasada (1984); Wang et al. (1998).
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.
![]() | Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme. |
![]() | Fig. 2. Crystal packing diagram of (I). Hydrogen bonds are shown as dashed lines. |
C18H18ClN7OS | F(000) = 1728 |
Mr = 415.90 | Dx = 1.380 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 1064 reflections |
a = 20.0916 (18) Å | θ = 2.8–16.5° |
b = 7.2538 (7) Å | µ = 0.32 mm−1 |
c = 28.046 (2) Å | T = 294 K |
β = 101.527 (2)° | Block, colorless |
V = 4005.0 (6) Å3 | 0.20 × 0.10 × 0.04 mm |
Z = 8 |
Bruker SMART APEX CCD area-detector diffractometer | 4343 independent reflections |
Radiation source: fine-focus sealed tube | 2226 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.096 |
φ and ω scans | θmax = 27.0°, θmin = 1.5° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | h = −25→25 |
Tmin = 0.939, Tmax = 0.987 | k = −9→9 |
17095 measured reflections | l = −33→35 |
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)] = 0.064 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.143 | H-atom parameters constrained |
S = 0.98 | w = 1/[σ2(Fo2) + (0.0523P)2] where P = (Fo2 + 2Fc2)/3 |
4343 reflections | (Δ/σ)max = 0.001 |
255 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.25 e Å−3 |
C18H18ClN7OS | V = 4005.0 (6) Å3 |
Mr = 415.90 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 20.0916 (18) Å | µ = 0.32 mm−1 |
b = 7.2538 (7) Å | T = 294 K |
c = 28.046 (2) Å | 0.20 × 0.10 × 0.04 mm |
β = 101.527 (2)° |
Bruker SMART APEX CCD area-detector diffractometer | 4343 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | 2226 reflections with I > 2σ(I) |
Tmin = 0.939, Tmax = 0.987 | Rint = 0.096 |
17095 measured reflections |
R[F2 > 2σ(F2)] = 0.064 | 0 restraints |
wR(F2) = 0.143 | H-atom parameters constrained |
S = 0.98 | Δρmax = 0.28 e Å−3 |
4343 reflections | Δρmin = −0.25 e Å−3 |
255 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 | 0.45437 (18) | −0.1881 (5) | 0.07899 (12) | 0.0475 (9) | |
C2 | 0.49843 (16) | −0.1194 (5) | 0.15347 (12) | 0.0456 (9) | |
H2 | 0.5333 | −0.1040 | 0.1805 | 0.055* | |
C3 | 0.43344 (15) | −0.0848 (4) | 0.15564 (11) | 0.0357 (8) | |
C4 | 0.40458 (15) | −0.0225 (5) | 0.19814 (11) | 0.0431 (9) | |
H4A | 0.4402 | −0.0224 | 0.2271 | 0.052* | |
H4B | 0.3880 | 0.1027 | 0.1925 | 0.052* | |
C5 | 0.28245 (15) | −0.1132 (4) | 0.19072 (10) | 0.0331 (7) | |
C6 | 0.25197 (16) | −0.2612 (4) | 0.20799 (11) | 0.0383 (8) | |
C7 | 0.17957 (17) | −0.2757 (5) | 0.19767 (11) | 0.0387 (8) | |
C8 | 0.18729 (16) | 0.0218 (4) | 0.15449 (11) | 0.0351 (8) | |
C9 | 0.18402 (17) | 0.3310 (4) | 0.11911 (13) | 0.0482 (9) | |
H9A | 0.2218 | 0.3564 | 0.1457 | 0.058* | |
H9B | 0.1518 | 0.4312 | 0.1179 | 0.058* | |
C10 | 0.2099 (2) | 0.3308 (6) | 0.07249 (15) | 0.0692 (12) | |
H10 | 0.2472 | 0.2415 | 0.0757 | 0.083* | |
C11 | 0.1566 (3) | 0.2773 (7) | 0.02910 (14) | 0.1029 (17) | |
H11A | 0.1441 | 0.1508 | 0.0321 | 0.154* | |
H11B | 0.1743 | 0.2926 | 0.0000 | 0.154* | |
H11C | 0.1174 | 0.3544 | 0.0275 | 0.154* | |
C12 | 0.2385 (2) | 0.5219 (6) | 0.06524 (18) | 0.1065 (18) | |
H12A | 0.2028 | 0.6118 | 0.0623 | 0.160* | |
H12B | 0.2569 | 0.5222 | 0.0362 | 0.160* | |
H12C | 0.2737 | 0.5517 | 0.0927 | 0.160* | |
C13 | 0.07716 (15) | −0.1286 (4) | 0.15216 (11) | 0.0341 (7) | |
C14 | 0.04907 (17) | −0.1883 (5) | 0.10585 (11) | 0.0461 (9) | |
H14 | 0.0768 | −0.2274 | 0.0850 | 0.055* | |
C15 | −0.02078 (19) | −0.1895 (5) | 0.09071 (13) | 0.0563 (10) | |
H15 | −0.0401 | −0.2282 | 0.0594 | 0.068* | |
C16 | −0.06186 (18) | −0.1337 (5) | 0.12179 (15) | 0.0555 (10) | |
H16 | −0.1088 | −0.1348 | 0.1114 | 0.067* | |
C17 | −0.03405 (18) | −0.0767 (5) | 0.16788 (14) | 0.0544 (10) | |
H17 | −0.0621 | −0.0401 | 0.1888 | 0.065* | |
C18 | 0.03624 (17) | −0.0733 (4) | 0.18352 (12) | 0.0446 (9) | |
H18 | 0.0554 | −0.0341 | 0.2148 | 0.054* | |
Cl1 | 0.44869 (6) | −0.26117 (17) | 0.02014 (3) | 0.0838 (4) | |
N1 | 0.51130 (14) | −0.1786 (4) | 0.10948 (10) | 0.0489 (8) | |
N2 | 0.34916 (12) | −0.1415 (4) | 0.20609 (9) | 0.0375 (7) | |
N3 | 0.36005 (14) | −0.3031 (4) | 0.23214 (9) | 0.0474 (7) | |
N4 | 0.30135 (14) | −0.3749 (4) | 0.23363 (9) | 0.0488 (8) | |
N5 | 0.15024 (12) | −0.1259 (3) | 0.16775 (8) | 0.0361 (6) | |
N6 | 0.25402 (12) | 0.0313 (4) | 0.16422 (9) | 0.0368 (7) | |
N7 | 0.15143 (13) | 0.1615 (4) | 0.13001 (9) | 0.0426 (7) | |
H7 | 0.1082 | 0.1501 | 0.1206 | 0.051* | |
O1 | 0.14303 (12) | −0.3936 (3) | 0.20981 (8) | 0.0531 (7) | |
S1 | 0.38275 (4) | −0.12598 (13) | 0.09935 (3) | 0.0491 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.052 (2) | 0.052 (2) | 0.0397 (19) | 0.0035 (19) | 0.0133 (17) | −0.0012 (17) |
C2 | 0.035 (2) | 0.055 (2) | 0.045 (2) | −0.0009 (18) | 0.0037 (15) | −0.0014 (18) |
C3 | 0.0272 (18) | 0.042 (2) | 0.0372 (18) | 0.0041 (15) | 0.0038 (14) | 0.0002 (15) |
C4 | 0.0303 (19) | 0.056 (2) | 0.044 (2) | −0.0006 (17) | 0.0084 (15) | −0.0054 (17) |
C5 | 0.0321 (18) | 0.040 (2) | 0.0281 (16) | 0.0018 (16) | 0.0090 (13) | −0.0037 (15) |
C6 | 0.037 (2) | 0.043 (2) | 0.0369 (18) | 0.0012 (17) | 0.0103 (15) | 0.0050 (16) |
C7 | 0.042 (2) | 0.044 (2) | 0.0312 (17) | −0.0009 (18) | 0.0085 (15) | 0.0017 (16) |
C8 | 0.0321 (19) | 0.039 (2) | 0.0348 (18) | 0.0020 (16) | 0.0086 (14) | 0.0011 (15) |
C9 | 0.041 (2) | 0.033 (2) | 0.068 (2) | 0.0025 (16) | 0.0060 (18) | 0.0090 (18) |
C10 | 0.062 (3) | 0.068 (3) | 0.080 (3) | −0.002 (2) | 0.020 (2) | 0.023 (2) |
C11 | 0.114 (4) | 0.131 (5) | 0.061 (3) | −0.028 (3) | 0.010 (3) | 0.007 (3) |
C12 | 0.106 (4) | 0.087 (4) | 0.138 (5) | −0.027 (3) | 0.052 (3) | 0.033 (3) |
C13 | 0.0316 (18) | 0.0351 (19) | 0.0353 (18) | −0.0028 (15) | 0.0061 (14) | 0.0012 (15) |
C14 | 0.043 (2) | 0.055 (2) | 0.0396 (19) | −0.0017 (18) | 0.0068 (16) | −0.0028 (17) |
C15 | 0.050 (2) | 0.064 (3) | 0.048 (2) | −0.009 (2) | −0.0092 (19) | 0.005 (2) |
C16 | 0.033 (2) | 0.053 (2) | 0.076 (3) | −0.0008 (19) | 0.001 (2) | 0.011 (2) |
C17 | 0.040 (2) | 0.053 (2) | 0.074 (3) | −0.0021 (18) | 0.022 (2) | −0.003 (2) |
C18 | 0.042 (2) | 0.051 (2) | 0.0417 (19) | −0.0083 (17) | 0.0088 (16) | −0.0063 (16) |
Cl1 | 0.0986 (9) | 0.1105 (10) | 0.0437 (6) | 0.0133 (7) | 0.0175 (6) | −0.0084 (6) |
N1 | 0.0382 (17) | 0.060 (2) | 0.0487 (18) | 0.0021 (15) | 0.0101 (14) | 0.0000 (16) |
N2 | 0.0318 (15) | 0.0440 (17) | 0.0366 (15) | 0.0012 (13) | 0.0068 (12) | 0.0025 (13) |
N3 | 0.0419 (18) | 0.0529 (19) | 0.0474 (17) | 0.0120 (15) | 0.0090 (14) | 0.0155 (15) |
N4 | 0.0411 (18) | 0.0506 (19) | 0.0550 (18) | 0.0101 (15) | 0.0105 (14) | 0.0185 (15) |
N5 | 0.0287 (14) | 0.0424 (16) | 0.0371 (15) | −0.0021 (13) | 0.0064 (11) | 0.0050 (13) |
N6 | 0.0289 (16) | 0.0404 (16) | 0.0414 (15) | 0.0008 (13) | 0.0075 (12) | 0.0079 (13) |
N7 | 0.0259 (14) | 0.0418 (17) | 0.0584 (17) | −0.0007 (13) | 0.0042 (13) | 0.0138 (14) |
O1 | 0.0468 (15) | 0.0507 (16) | 0.0617 (16) | −0.0091 (13) | 0.0108 (12) | 0.0176 (13) |
S1 | 0.0348 (5) | 0.0655 (7) | 0.0443 (5) | 0.0008 (5) | 0.0014 (4) | −0.0024 (5) |
C1—N1 | 1.286 (4) | C10—C11 | 1.503 (5) |
C1—S1 | 1.711 (4) | C10—C12 | 1.529 (5) |
C1—Cl1 | 1.715 (3) | C10—H10 | 0.9800 |
C2—C3 | 1.343 (4) | C11—H11A | 0.9600 |
C2—N1 | 1.379 (4) | C11—H11B | 0.9600 |
C2—H2 | 0.9300 | C11—H11C | 0.9600 |
C3—C4 | 1.496 (4) | C12—H12A | 0.9600 |
C3—S1 | 1.725 (3) | C12—H12B | 0.9600 |
C4—N2 | 1.460 (4) | C12—H12C | 0.9600 |
C4—H4A | 0.9700 | C13—C18 | 1.378 (4) |
C4—H4B | 0.9700 | C13—C14 | 1.378 (4) |
C5—N2 | 1.339 (4) | C13—N5 | 1.446 (4) |
C5—N6 | 1.344 (4) | C14—C15 | 1.383 (4) |
C5—C6 | 1.372 (4) | C14—H14 | 0.9300 |
C6—N4 | 1.377 (4) | C15—C16 | 1.375 (5) |
C6—C7 | 1.429 (4) | C15—H15 | 0.9300 |
C7—O1 | 1.219 (3) | C16—C17 | 1.366 (5) |
C7—N5 | 1.426 (4) | C16—H16 | 0.9300 |
C8—N6 | 1.316 (4) | C17—C18 | 1.393 (4) |
C8—N7 | 1.349 (4) | C17—H17 | 0.9300 |
C8—N5 | 1.397 (4) | C18—H18 | 0.9300 |
C9—N7 | 1.454 (4) | N2—N3 | 1.376 (3) |
C9—C10 | 1.501 (5) | N3—N4 | 1.298 (3) |
C9—H9A | 0.9700 | N7—H7 | 0.8600 |
C9—H9B | 0.9700 | ||
N1—C1—S1 | 117.4 (3) | C10—C11—H11C | 109.5 |
N1—C1—Cl1 | 122.4 (3) | H11A—C11—H11C | 109.5 |
S1—C1—Cl1 | 120.3 (2) | H11B—C11—H11C | 109.5 |
C3—C2—N1 | 117.2 (3) | C10—C12—H12A | 109.5 |
C3—C2—H2 | 121.4 | C10—C12—H12B | 109.5 |
N1—C2—H2 | 121.4 | H12A—C12—H12B | 109.5 |
C2—C3—C4 | 128.9 (3) | C10—C12—H12C | 109.5 |
C2—C3—S1 | 109.1 (2) | H12A—C12—H12C | 109.5 |
C4—C3—S1 | 122.0 (2) | H12B—C12—H12C | 109.5 |
N2—C4—C3 | 111.8 (3) | C18—C13—C14 | 120.6 (3) |
N2—C4—H4A | 109.2 | C18—C13—N5 | 120.2 (3) |
C3—C4—H4A | 109.2 | C14—C13—N5 | 119.3 (3) |
N2—C4—H4B | 109.2 | C13—C14—C15 | 119.4 (3) |
C3—C4—H4B | 109.2 | C13—C14—H14 | 120.3 |
H4A—C4—H4B | 107.9 | C15—C14—H14 | 120.3 |
N2—C5—N6 | 125.8 (3) | C16—C15—C14 | 120.3 (3) |
N2—C5—C6 | 104.8 (3) | C16—C15—H15 | 119.9 |
N6—C5—C6 | 129.4 (3) | C14—C15—H15 | 119.9 |
C5—C6—N4 | 109.1 (3) | C17—C16—C15 | 120.3 (3) |
C5—C6—C7 | 119.6 (3) | C17—C16—H16 | 119.8 |
N4—C6—C7 | 131.3 (3) | C15—C16—H16 | 119.8 |
O1—C7—N5 | 119.8 (3) | C16—C17—C18 | 120.1 (3) |
O1—C7—C6 | 129.8 (3) | C16—C17—H17 | 120.0 |
N5—C7—C6 | 110.3 (3) | C18—C17—H17 | 120.0 |
N6—C8—N7 | 119.0 (3) | C13—C18—C17 | 119.4 (3) |
N6—C8—N5 | 124.1 (3) | C13—C18—H18 | 120.3 |
N7—C8—N5 | 116.9 (3) | C17—C18—H18 | 120.3 |
N7—C9—C10 | 115.6 (3) | C1—N1—C2 | 108.1 (3) |
N7—C9—H9A | 108.4 | C5—N2—N3 | 110.1 (3) |
C10—C9—H9A | 108.4 | C5—N2—C4 | 127.2 (3) |
N7—C9—H9B | 108.4 | N3—N2—C4 | 122.6 (3) |
C10—C9—H9B | 108.4 | N4—N3—N2 | 108.1 (2) |
H9A—C9—H9B | 107.4 | N3—N4—C6 | 107.9 (3) |
C9—C10—C11 | 113.0 (3) | C8—N5—C7 | 124.1 (3) |
C9—C10—C12 | 108.6 (4) | C8—N5—C13 | 119.5 (2) |
C11—C10—C12 | 110.6 (4) | C7—N5—C13 | 116.3 (2) |
C9—C10—H10 | 108.2 | C8—N6—C5 | 112.1 (3) |
C11—C10—H10 | 108.2 | C8—N7—C9 | 121.7 (3) |
C12—C10—H10 | 108.2 | C8—N7—H7 | 119.2 |
C10—C11—H11A | 109.5 | C9—N7—H7 | 119.2 |
C10—C11—H11B | 109.5 | C1—S1—C3 | 88.22 (16) |
H11A—C11—H11B | 109.5 | ||
N1—C2—C3—C4 | 179.0 (3) | C3—C4—N2—N3 | 84.1 (3) |
N1—C2—C3—S1 | −0.4 (4) | C5—N2—N3—N4 | −0.6 (3) |
C2—C3—C4—N2 | −127.6 (3) | C4—N2—N3—N4 | 178.7 (3) |
S1—C3—C4—N2 | 51.7 (4) | N2—N3—N4—C6 | 0.7 (3) |
N2—C5—C6—N4 | 0.3 (3) | C5—C6—N4—N3 | −0.6 (4) |
N6—C5—C6—N4 | −179.7 (3) | C7—C6—N4—N3 | 179.1 (3) |
N2—C5—C6—C7 | −179.5 (3) | N6—C8—N5—C7 | 6.6 (5) |
N6—C5—C6—C7 | 0.5 (5) | N7—C8—N5—C7 | −173.7 (3) |
C5—C6—C7—O1 | −179.3 (3) | N6—C8—N5—C13 | −175.5 (3) |
N4—C6—C7—O1 | 1.0 (6) | N7—C8—N5—C13 | 4.2 (4) |
C5—C6—C7—N5 | 2.1 (4) | O1—C7—N5—C8 | 175.8 (3) |
N4—C6—C7—N5 | −177.6 (3) | C6—C7—N5—C8 | −5.5 (4) |
N7—C9—C10—C11 | 53.4 (5) | O1—C7—N5—C13 | −2.1 (4) |
N7—C9—C10—C12 | 176.6 (3) | C6—C7—N5—C13 | 176.7 (3) |
C18—C13—C14—C15 | 1.1 (5) | C18—C13—N5—C8 | −98.9 (3) |
N5—C13—C14—C15 | −179.5 (3) | C14—C13—N5—C8 | 81.6 (4) |
C13—C14—C15—C16 | −0.8 (5) | C18—C13—N5—C7 | 79.0 (4) |
C14—C15—C16—C17 | 0.0 (6) | C14—C13—N5—C7 | −100.4 (3) |
C15—C16—C17—C18 | 0.5 (5) | N7—C8—N6—C5 | 177.0 (3) |
C14—C13—C18—C17 | −0.5 (5) | N5—C8—N6—C5 | −3.3 (4) |
N5—C13—C18—C17 | 180.0 (3) | N2—C5—N6—C8 | 179.9 (3) |
C16—C17—C18—C13 | −0.3 (5) | C6—C5—N6—C8 | −0.1 (4) |
S1—C1—N1—C2 | 0.9 (4) | N6—C8—N7—C9 | −7.2 (5) |
Cl1—C1—N1—C2 | −178.7 (3) | N5—C8—N7—C9 | 173.1 (3) |
C3—C2—N1—C1 | −0.3 (4) | C10—C9—N7—C8 | 88.0 (4) |
N6—C5—N2—N3 | −179.9 (3) | N1—C1—S1—C3 | −1.0 (3) |
C6—C5—N2—N3 | 0.2 (3) | Cl1—C1—S1—C3 | 178.6 (2) |
N6—C5—N2—C4 | 0.9 (5) | C2—C3—S1—C1 | 0.7 (3) |
C6—C5—N2—C4 | −179.1 (3) | C4—C3—S1—C1 | −178.8 (3) |
C3—C4—N2—C5 | −96.8 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N7—H7···N1i | 0.86 | 2.28 | 2.993 (4) | 141 |
Symmetry code: (i) x−1/2, y+1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C18H18ClN7OS |
Mr | 415.90 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 294 |
a, b, c (Å) | 20.0916 (18), 7.2538 (7), 28.046 (2) |
β (°) | 101.527 (2) |
V (Å3) | 4005.0 (6) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.32 |
Crystal size (mm) | 0.20 × 0.10 × 0.04 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2001) |
Tmin, Tmax | 0.939, 0.987 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17095, 4343, 2226 |
Rint | 0.096 |
(sin θ/λ)max (Å−1) | 0.639 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.064, 0.143, 0.98 |
No. of reflections | 4343 |
No. of parameters | 255 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.28, −0.25 |
Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1997), SHELXTL.
C5—N6 | 1.344 (4) | C8—N5 | 1.397 (4) |
C6—N4 | 1.377 (4) | C9—N7 | 1.454 (4) |
C7—N5 | 1.426 (4) | C13—N5 | 1.446 (4) |
C8—N6 | 1.316 (4) | N2—N3 | 1.376 (3) |
C8—N7 | 1.349 (4) | N3—N4 | 1.298 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N7—H7···N1i | 0.86 | 2.28 | 2.993 (4) | 140.6 |
Symmetry code: (i) x−1/2, y+1/2, z. |
8-aza analogues of similarly substituted purines ([1,2,3]triazolo[4,5-d]pyrimidines are one such example) have been synthesized in recent years, and many of them exhibit broad spectral biological activities, such as the interesting antifungal (Roblin et al., 1945), antiviral (Shealy et al., 1984), anticancer (Kidder et al., 1951) and antiallergic (Lunt, 1982) activities. Recently, we have developed a versatile method via tandem aza-Wittig, followed by the cyclization to synthesize the novel triazolo[4,5-d]-pyrimidine derivatives (Ding et al., 2004; Wang et al., 2004). In this paper, we report the structure of the title compound, (I) (Fig. 1). In the triazolopyrimidine ring, the C5—N2, C5—N6, C6—N4, C7—N5 and C8—N5 bonds, Tabel 1, are significantly shorter than a normal single C—N bond (1.47 Å; Sasada, 1984) and closer to the value for a C═N bond (1.28 Å; Wang et al., 1998). This indicates significant electron delocalization in the triazolo[4,5-d]pyrimidinyl system.
In the crystal structure, intermolecular N—H···N hydrogen-bonds contribute strongly to the stability of the molecular configuration (Fig.2 and Table 1). In addition, short intermolecular distances between the centroids of the C1–C2/N1/S1 ring (Cg1) and the C13–C18 ring (Cg4) of the adjacent molecule indicate the existence of weak π— π stacking interactions [Cg1···Cg4i =3.7237 (20) Å, dihedral angles of 5.94 (16)°, and a shortest interplanar distance of 3.388 Å.; symmetry code: (i) 1/2 + x, -1/2 + y, z.