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Acta Crystallogr Sect E Struct Rep Online. 2008 January 1; 64(Pt 1): o44.
Published online 2007 December 6. doi:  10.1107/S1600536807062174
PMCID: PMC2915002

Ethyl 2-benzyl­sulfanyl-7-(2-chloro­phen­yl)-5-methyl-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-6-carboxyl­ate

Abstract

In the title compound, C22H21ClN4O2S, the bicyclic triazolopyrimidine ring system is nearly planar, and oriented at dihedral angles of 89.45 (3)° with respect to the chlorobenzene ring and 87.03 (3)° with respect to the terminal phenyl ring. In the crystal structure, mol­ecules are linked by π–π stacking inter­actions between the triazolopyrimidine rings [centroid–centroid distances of 3.88 (1) and 3.63 (1) Å].

Related literature

For general background, see: Fedorova et al. (2003 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]).

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Object name is e-64-00o44-scheme1.jpg

Experimental

Crystal data

  • C22H21ClN4O2S
  • M r = 440.94
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-00o44-efi1.jpg
  • a = 7.5884 (9) Å
  • b = 10.7303 (12) Å
  • c = 14.8825 (16) Å
  • α = 70.655 (2)°
  • β = 86.097 (2)°
  • γ = 70.032 (2)°
  • V = 1073.3 (2) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.30 mm−1
  • T = 292 (2) K
  • 0.30 × 0.20 × 0.20 mm

Data collection

  • Bruker SMART 4K CCD area-detector diffractometer
  • Absorption correction: none
  • 7183 measured reflections
  • 4374 independent reflections
  • 3305 reflections with I > 2σ(I)
  • R int = 0.042

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.143
  • S = 1.07
  • 4374 reflections
  • 277 parameters
  • 1 restraint
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.27 e Å−3
  • Δρmin = −0.25 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 [triangle]); molecular graphics: PLATON (Spek, 2003 [triangle]); software used to prepare material for publication: SHELXTL (Bruker, 2001 [triangle]).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536807062174/hk2397sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807062174/hk2397Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by NNSFC grants (Nos. 20572030, 20432010 and 20528201), the Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China (grant No. 705039), and the Programme for Excellent Research Groups of Hubei Province (grant No. 2004ABC002).

supplementary crystallographic information

Comment

In recent years, growing attention has been paid to analogues of purines and nucleosides, including azolopyrimidines containing the bridge head nitrogen atom and their dihydro derivatives, among which promising biologically active compounds were found (Fedorova et al., 2003). We synthesized a novel class of ethyl 7-alkylthio-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-6- carboxylate derivatives by three component condensation of 3-amino-5-alkyl- thio-1,2,4-triazoles with aromatic aldehydes and β-keto ester. We report herein the crystal structure of one such analogue, a triazolopyrimidine derivative, the title compound, (I).

In the molecule of (I), (Fig. 1) the bond lengths and angles are within normal ranges (Allen et al., 1987). Rings A (C1—C6), B (N1—N3/C8/C9), C (N3/N4/C9/C10/C12/C13) and D (C14—C19) are, of course, planar. The bicyclic triazolopyrimidine ring system (N1—N4/C8—C10/C12/C13) is nearly planar with a maximum deviation of 0.034 (2) Å (for atom C8), and it is oriented with respect to rings A and D at dihedral angles of 87.03 (3)° and 89.45 (3)°, respectively.

In the crystal structure (Fig. 2), molecules are linked by π···π stacking interactions involving B and C rings of the adjacent molecules with a centroid-centroid distance of 3.88 (1) Å (symmetry code: 1 - x, -y, 1 - z). The adjacent B rings have a centroid-centroid distance of 3.63 (1) %A (symmetry code: 1 - x, -y, 1 - z).

Experimental

For the preparation of the title compound, a mixture of acetylacetic ester (1 mmol), 2-chloro benzaldehyde (1 mmol) and 3-amino-5-benzyllthio-1,2,4 -triazole (1 mmol) in EtOH (3 ml) was added into a microwave tube. The sealed tube was placed in a Smith synthesizer and irradiated at 323 K for 30 min. The reaction mixture was cooled to room temperature, and the precipitate was filtered and recrystallized from ethanol to give the title compound, (I). Single crystals of (I), suitable for X-ray analysis were grown from an acetone solution at 293 K. 1H NMR (CDCl3, 400 MHz): σ 10.89(s, 1 H), 7.14–7.41(m, 9 H), 6.84(s, 1H), 4.25(d, 1H), 4.11(d, 1H), 4.02(q,2 H), 2.59(s, 3H),1.08(t, 3H).

Refinement

H atom (for NH) was located in a difference sythesis and refined isotropically [N—H = 0.857 (10) Å and Uiso(H) = 0.060 (7) Å2]. The remaining H atoms were positioned geometrically, with C—H = 0.93, 0.98, 0.97 and 0.96 Å for aromatic, methine, methylene and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms.

Figures

Fig. 1.
The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
A packing diagram of (I).

Crystal data

C22H21ClN4O2SZ = 2
Mr = 440.94F000 = 460
Triclinic, P1Dx = 1.364 Mg m3
Hall symbol: -P 1Mo Kα radiation λ = 0.71073 Å
a = 7.5884 (9) ÅCell parameters from 2807 reflections
b = 10.7303 (12) Åθ = 2.9–27.5º
c = 14.8825 (16) ŵ = 0.30 mm1
α = 70.655 (2)ºT = 292 (2) K
β = 86.097 (2)ºBlock, colorless
γ = 70.032 (2)º0.30 × 0.20 × 0.20 mm
V = 1073.3 (2) Å3

Data collection

Bruker SMART 4K CCD area-detector diffractometer3305 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.042
Monochromator: graphiteθmax = 26.5º
T = 292(2) Kθmin = 2.1º
[var phi] and ω scansh = −9→9
Absorption correction: nonek = −13→9
7183 measured reflectionsl = −18→15
4374 independent reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.048H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.143  w = 1/[σ2(Fo2) + (0.0766P)2 + 0.0197P] where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max = 0.004
4374 reflectionsΔρmax = 0.27 e Å3
277 parametersΔρmin = −0.25 e Å3
1 restraintExtinction correction: none
Primary atom site location: structure-invariant direct methods

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Cl10.00615 (8)0.74321 (8)0.62526 (6)0.0777 (3)
S10.56904 (7)0.74334 (6)0.26984 (4)0.04454 (19)
O10.3353 (2)0.58296 (17)0.80362 (10)0.0535 (4)
O20.6149 (3)0.4999 (3)0.87766 (13)0.1116 (10)
N10.4468 (2)0.69605 (17)0.45014 (11)0.0355 (4)
N20.7612 (2)0.59780 (17)0.43894 (11)0.0348 (4)
N30.5383 (2)0.62604 (17)0.53959 (11)0.0341 (4)
N40.8411 (2)0.4984 (2)0.60747 (12)0.0427 (5)
H4A0.9574 (16)0.473 (2)0.5949 (17)0.060 (7)*
C10.3133 (4)1.0947 (3)0.1521 (2)0.0676 (7)
H10.33801.10770.20810.081*
C20.2929 (4)1.2023 (3)0.0662 (2)0.0850 (10)
H20.30461.28650.06460.102*
C30.2559 (4)1.1840 (4)−0.0153 (2)0.0835 (10)
H30.24311.2559−0.07320.100*
C40.2374 (4)1.0625 (4)−0.0136 (2)0.0831 (10)
H40.21191.0507−0.06990.100*
C50.2567 (4)0.9554 (3)0.07242 (19)0.0660 (7)
H50.24170.87230.07370.079*
C60.2977 (3)0.9705 (3)0.15594 (15)0.0495 (6)
C70.3236 (3)0.8548 (3)0.24988 (18)0.0621 (7)
H7A0.24580.79960.24950.075*
H7B0.28590.89440.30090.075*
C80.5887 (3)0.6745 (2)0.39400 (13)0.0341 (4)
C90.7215 (2)0.5707 (2)0.52975 (13)0.0317 (4)
C100.7745 (3)0.4899 (2)0.69732 (14)0.0383 (5)
C110.9306 (3)0.4099 (3)0.77410 (16)0.0550 (6)
H11A0.99490.47100.77830.082*
H11B1.01750.33180.75850.082*
H11C0.87850.37620.83420.082*
C120.5919 (3)0.5486 (2)0.70996 (14)0.0386 (5)
C130.4428 (3)0.6291 (2)0.62811 (13)0.0319 (4)
H130.35010.58180.63580.038*
C140.3429 (3)0.7812 (2)0.62213 (13)0.0350 (4)
C150.4487 (3)0.8657 (2)0.61846 (16)0.0492 (6)
H150.57890.82800.61980.059*
C160.3652 (5)1.0036 (3)0.6129 (2)0.0687 (8)
H160.43851.05840.61100.082*
C170.1726 (5)1.0605 (3)0.6103 (2)0.0786 (9)
H170.11581.15370.60700.094*
C180.0637 (4)0.9802 (3)0.61266 (19)0.0689 (8)
H18−0.06651.01930.60980.083*
C190.1489 (3)0.8412 (2)0.61929 (16)0.0466 (5)
C200.5222 (3)0.5380 (3)0.80635 (16)0.0561 (7)
C210.2431 (4)0.6005 (3)0.88953 (18)0.0694 (8)
H21A0.31700.52830.94510.083*
H21B0.12070.59060.88970.083*
C220.2210 (4)0.7414 (4)0.8942 (2)0.0875 (10)
H22A0.34250.74800.89980.131*
H22B0.15140.75470.94860.131*
H22C0.15470.81260.83720.131*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.0371 (3)0.0746 (5)0.1093 (6)−0.0209 (3)−0.0024 (3)−0.0116 (4)
S10.0428 (3)0.0496 (4)0.0296 (3)−0.0035 (2)−0.0003 (2)−0.0104 (2)
O10.0514 (9)0.0655 (11)0.0360 (8)−0.0116 (8)0.0119 (7)−0.0175 (8)
O20.0598 (12)0.191 (3)0.0364 (11)0.0100 (14)−0.0070 (9)−0.0289 (13)
N10.0338 (8)0.0388 (10)0.0301 (8)−0.0072 (7)−0.0019 (6)−0.0111 (7)
N20.0324 (8)0.0383 (10)0.0319 (9)−0.0079 (7)−0.0003 (6)−0.0129 (7)
N30.0326 (8)0.0373 (9)0.0279 (8)−0.0050 (7)−0.0007 (6)−0.0115 (7)
N40.0304 (9)0.0548 (12)0.0321 (9)−0.0044 (8)0.0003 (7)−0.0108 (8)
C10.0695 (17)0.0662 (18)0.0560 (16)−0.0130 (14)−0.0143 (13)−0.0132 (14)
C20.081 (2)0.066 (2)0.081 (2)−0.0156 (17)−0.0161 (17)0.0031 (17)
C30.0563 (17)0.096 (3)0.0545 (18)−0.0082 (17)−0.0071 (13)0.0148 (18)
C40.0726 (19)0.110 (3)0.0423 (16)−0.0028 (19)−0.0116 (13)−0.0199 (17)
C50.0603 (16)0.0753 (19)0.0547 (16)−0.0098 (14)−0.0082 (12)−0.0232 (14)
C60.0347 (11)0.0571 (15)0.0402 (12)−0.0010 (10)−0.0045 (9)−0.0087 (11)
C70.0415 (12)0.0680 (17)0.0490 (14)−0.0026 (12)−0.0010 (10)0.0002 (12)
C80.0394 (10)0.0297 (10)0.0310 (10)−0.0069 (8)−0.0003 (8)−0.0118 (8)
C90.0294 (9)0.0324 (10)0.0337 (10)−0.0097 (8)0.0005 (8)−0.0120 (8)
C100.0410 (11)0.0388 (12)0.0308 (10)−0.0102 (9)−0.0009 (8)−0.0087 (9)
C110.0398 (12)0.0708 (17)0.0410 (13)−0.0093 (11)−0.0071 (9)−0.0094 (12)
C120.0404 (11)0.0395 (12)0.0312 (10)−0.0084 (9)−0.0010 (8)−0.0104 (9)
C130.0311 (9)0.0358 (11)0.0295 (10)−0.0119 (8)0.0045 (7)−0.0118 (8)
C140.0390 (10)0.0359 (11)0.0291 (10)−0.0116 (9)0.0036 (8)−0.0111 (8)
C150.0508 (13)0.0477 (14)0.0553 (14)−0.0207 (11)0.0022 (11)−0.0205 (11)
C160.097 (2)0.0515 (16)0.0724 (19)−0.0353 (16)0.0013 (16)−0.0280 (14)
C170.114 (3)0.0395 (15)0.0695 (19)−0.0033 (17)0.0066 (17)−0.0253 (14)
C180.0657 (17)0.0520 (16)0.0658 (17)0.0071 (13)0.0101 (13)−0.0194 (14)
C190.0425 (12)0.0437 (13)0.0452 (12)−0.0071 (10)0.0046 (9)−0.0123 (10)
C200.0497 (13)0.0652 (16)0.0344 (12)−0.0010 (11)0.0008 (10)−0.0109 (11)
C210.0662 (17)0.090 (2)0.0438 (14)−0.0183 (15)0.0244 (12)−0.0237 (14)
C220.080 (2)0.109 (3)0.082 (2)−0.0193 (19)0.0220 (17)−0.058 (2)

Geometric parameters (Å, °)

Cl1—C191.729 (2)C10—C111.512 (3)
N1—C81.322 (2)C11—H11A0.9600
N1—N31.387 (2)C11—H11B0.9600
N2—C91.321 (2)C11—H11C0.9600
N2—C81.362 (2)C12—C201.477 (3)
N3—C91.332 (2)C12—C131.528 (3)
N3—C131.464 (2)C13—C141.521 (3)
N4—C91.353 (2)C13—H130.9800
N4—C101.382 (2)C14—C191.388 (3)
N4—H4A0.857 (10)C14—C151.388 (3)
C1—C61.360 (4)C15—C161.373 (3)
C1—C21.385 (4)C15—H150.9300
C1—H10.9300C16—C171.376 (4)
C2—C31.354 (4)C16—H160.9300
C2—H20.9300C17—C181.374 (4)
C3—C41.350 (4)C17—H170.9300
C3—H30.9300C18—C191.381 (3)
C4—C51.384 (4)C18—H180.9300
C4—H40.9300C20—O21.186 (3)
C5—C61.375 (3)C20—O11.331 (3)
C5—H50.9300C21—O11.452 (3)
C6—C71.502 (3)C21—C221.488 (4)
C7—S11.818 (2)C21—H21A0.9700
C7—H7A0.9700C21—H21B0.9700
C7—H7B0.9700C22—H22A0.9600
C8—S11.744 (2)C22—H22B0.9600
C10—C121.341 (3)C22—H22C0.9600
C8—N1—N3101.27 (15)H11B—C11—H11C109.5
C9—N2—C8102.11 (15)C10—C12—C20121.06 (19)
C9—N3—N1109.35 (15)C10—C12—C13123.50 (18)
C9—N3—C13127.46 (15)C20—C12—C13115.45 (17)
N1—N3—C13122.90 (14)N3—C13—C14108.91 (15)
C9—N4—C10119.78 (17)N3—C13—C12107.18 (15)
C9—N4—H4A114.4 (16)C14—C13—C12113.01 (16)
C10—N4—H4A125.0 (16)N3—C13—H13109.2
C6—C1—C2121.1 (3)C14—C13—H13109.2
C6—C1—H1119.4C12—C13—H13109.2
C2—C1—H1119.4C19—C14—C15117.7 (2)
C3—C2—C1119.5 (3)C19—C14—C13123.08 (19)
C3—C2—H2120.2C15—C14—C13119.19 (18)
C1—C2—H2120.2C16—C15—C14121.4 (2)
C4—C3—C2120.6 (3)C16—C15—H15119.3
C4—C3—H3119.7C14—C15—H15119.3
C2—C3—H3119.7C15—C16—C17119.7 (3)
C3—C4—C5119.8 (3)C15—C16—H16120.2
C3—C4—H4120.1C17—C16—H16120.2
C5—C4—H4120.1C18—C17—C16120.4 (2)
C6—C5—C4120.6 (3)C18—C17—H17119.8
C6—C5—H5119.7C16—C17—H17119.8
C4—C5—H5119.7C17—C18—C19119.5 (3)
C1—C6—C5118.3 (2)C17—C18—H18120.2
C1—C6—C7120.0 (2)C19—C18—H18120.2
C5—C6—C7121.7 (3)C18—C19—C14121.2 (2)
C6—C7—S1109.29 (16)C18—C19—Cl1117.8 (2)
C6—C7—H7A109.8C14—C19—Cl1120.93 (17)
S1—C7—H7A109.8O2—C20—O1122.7 (2)
C6—C7—H7B109.8O2—C20—C12126.4 (2)
S1—C7—H7B109.8O1—C20—C12110.83 (19)
H7A—C7—H7B108.3O1—C21—C22110.2 (2)
N1—C8—N2115.88 (17)O1—C21—H21A109.6
N1—C8—S1124.52 (15)C22—C21—H21A109.6
N2—C8—S1119.54 (14)O1—C21—H21B109.6
N2—C9—N3111.39 (16)C22—C21—H21B109.6
N2—C9—N4128.22 (17)H21A—C21—H21B108.1
N3—C9—N4120.38 (17)C21—C22—H22A109.5
C12—C10—N4121.53 (18)C21—C22—H22B109.5
C12—C10—C11126.76 (19)H22A—C22—H22B109.5
N4—C10—C11111.71 (18)C21—C22—H22C109.5
C10—C11—H11A109.5H22A—C22—H22C109.5
C10—C11—H11B109.5H22B—C22—H22C109.5
H11A—C11—H11B109.5C20—O1—C21117.94 (19)
C10—C11—H11C109.5C8—S1—C7101.13 (10)
H11A—C11—H11C109.5
C8—N1—N3—C90.3 (2)C9—N3—C13—C12−3.3 (3)
C8—N1—N3—C13174.42 (17)N1—N3—C13—C12−176.31 (16)
C6—C1—C2—C30.3 (5)C10—C12—C13—N30.6 (3)
C1—C2—C3—C40.5 (5)C20—C12—C13—N3−179.11 (18)
C2—C3—C4—C5−0.1 (5)C10—C12—C13—C14−119.4 (2)
C3—C4—C5—C6−1.1 (4)C20—C12—C13—C1460.9 (2)
C2—C1—C6—C5−1.5 (4)N3—C13—C14—C19113.7 (2)
C2—C1—C6—C7179.0 (2)C12—C13—C14—C19−127.3 (2)
C4—C5—C6—C11.9 (4)N3—C13—C14—C15−65.7 (2)
C4—C5—C6—C7−178.6 (2)C12—C13—C14—C1553.3 (2)
C1—C6—C7—S1−91.0 (3)C19—C14—C15—C160.5 (3)
C5—C6—C7—S189.5 (3)C13—C14—C15—C16179.9 (2)
N3—N1—C8—N2−0.1 (2)C14—C15—C16—C17−0.4 (4)
N3—N1—C8—S1−177.04 (14)C15—C16—C17—C18−0.4 (4)
C9—N2—C8—N1−0.2 (2)C16—C17—C18—C191.1 (4)
C9—N2—C8—S1176.97 (14)C17—C18—C19—C14−1.0 (4)
C8—N2—C9—N30.3 (2)C17—C18—C19—Cl1178.3 (2)
C8—N2—C9—N4−179.2 (2)C15—C14—C19—C180.3 (3)
N1—N3—C9—N2−0.4 (2)C13—C14—C19—C18−179.2 (2)
C13—N3—C9—N2−174.21 (17)C15—C14—C19—Cl1−179.04 (16)
N1—N3—C9—N4179.18 (18)C13—C14—C19—Cl11.5 (3)
C13—N3—C9—N45.4 (3)C10—C12—C20—O212.7 (4)
C10—N4—C9—N2175.17 (19)C13—C12—C20—O2−167.6 (3)
C10—N4—C9—N3−4.3 (3)C10—C12—C20—O1−169.8 (2)
C9—N4—C10—C121.9 (3)C13—C12—C20—O19.9 (3)
C9—N4—C10—C11−177.66 (19)O2—C20—O1—C217.1 (4)
N4—C10—C12—C20179.6 (2)C12—C20—O1—C21−170.5 (2)
C11—C10—C12—C20−1.0 (4)C22—C21—O1—C2085.4 (3)
N4—C10—C12—C13−0.1 (3)N1—C8—S1—C75.3 (2)
C11—C10—C12—C13179.4 (2)N2—C8—S1—C7−171.56 (17)
C9—N3—C13—C14119.3 (2)C6—C7—S1—C8154.37 (19)
N1—N3—C13—C14−53.7 (2)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HK2397).

References

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  • Sheldrick, G. M. (1997). SHELXS97 and SHELXL97 University of Göttingen, Germany.
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