organic compounds
5-[3-(2,5-Dimethoxyphenyl)prop-2-enylidene]-1,3-diethyl-2-thioxohexahydropyrimidine-4,6-dione
aChemistry Department, Faculty of Science, King Abdul Aziz University, Jeddah, Saudi Arabia, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
1,3-Diethyl-2-thiobarbituric acid reacts with 2,5-dimethoxybenzaldehyde to form the title Knoevenagel product, C19H22N2O4S. In the compound, the two six-membered rings at either end of the three-membered –CHCHCH– chain are nearly coplanar with this fragment (r.m.s. deviation of the two six-membered rings and the three chain atoms = 0.08 Å).
Related literature
For the reaction of 1,3-diethyl-2-thiobarbituric acid with aromatic et al. (1999).
to form the Knoevenagel and Michael products, see: AdamsonExperimental
Crystal data
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Data collection: APEX2 (Bruker, 2008); cell SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).
Supporting information
10.1107/S1600536809026099/xu2548sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809026099/xu2548Isup2.hkl
1,3-Diethyl-2-thiobarbituric acid (1 g, 0.005 mol) and 2,5-dimethoxybenzaldehyde (0.83 g, 0.005 mol) were heated in ethanol (15 ml) for 3 h; several drops of pyridine were added. The progress of reaction was monitored by TLC. The solid that seperated from the cool mixture was collected and recrystallized from a methanol-chloroform mixture in 50% yield; m.p. 454 K.
Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 to 0.99 Å) and were included in the
in the riding model approximation, with Uiso(H) fixed at 1.2–1.5Ueq(C).Data collection: APEX2 (Bruker, 2008); cell
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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C19H22N2O4S at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius. |
C19H22N2O4S | F(000) = 792 |
Mr = 374.45 | Dx = 1.369 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 4985 reflections |
a = 10.0519 (2) Å | θ = 2.2–28.3° |
b = 15.5942 (3) Å | µ = 0.21 mm−1 |
c = 11.5920 (2) Å | T = 140 K |
β = 90.813 (1)° | Irregular, gold–green |
V = 1816.88 (6) Å3 | 0.35 × 0.25 × 0.15 mm |
Z = 4 |
Bruker SMART APEX diffractometer | 4124 independent reflections |
Radiation source: fine-focus sealed tube | 3351 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.021 |
ω scans | θmax = 27.5°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −12→13 |
Tmin = 0.932, Tmax = 0.970 | k = −20→19 |
12384 measured reflections | l = −15→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)] = 0.039 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.119 | H-atom parameters constrained |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0635P)2 + 0.8319P] where P = (Fo2 + 2Fc2)/3 |
4124 reflections | (Δ/σ)max = 0.001 |
239 parameters | Δρmax = 0.38 e Å−3 |
0 restraints | Δρmin = −0.31 e Å−3 |
C19H22N2O4S | V = 1816.88 (6) Å3 |
Mr = 374.45 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 10.0519 (2) Å | µ = 0.21 mm−1 |
b = 15.5942 (3) Å | T = 140 K |
c = 11.5920 (2) Å | 0.35 × 0.25 × 0.15 mm |
β = 90.813 (1)° |
Bruker SMART APEX diffractometer | 4124 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 3351 reflections with I > 2σ(I) |
Tmin = 0.932, Tmax = 0.970 | Rint = 0.021 |
12384 measured reflections |
R[F2 > 2σ(F2)] = 0.039 | 0 restraints |
wR(F2) = 0.119 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.38 e Å−3 |
4124 reflections | Δρmin = −0.31 e Å−3 |
239 parameters |
x | y | z | Uiso*/Ueq | ||
S1 | 0.45514 (5) | 0.17006 (3) | 0.48043 (5) | 0.04028 (15) | |
O1 | 0.65557 (12) | 0.44794 (7) | 0.58487 (12) | 0.0369 (3) | |
O2 | 0.88016 (13) | 0.19441 (7) | 0.68934 (12) | 0.0368 (3) | |
O3 | 1.30863 (11) | 0.51465 (7) | 0.76778 (11) | 0.0323 (3) | |
O4 | 1.02427 (13) | 0.79694 (8) | 0.61792 (13) | 0.0412 (3) | |
N1 | 0.57177 (12) | 0.31723 (8) | 0.53660 (11) | 0.0229 (3) | |
N2 | 0.67570 (13) | 0.19089 (8) | 0.60462 (11) | 0.0238 (3) | |
C1 | 0.67099 (15) | 0.37060 (9) | 0.58438 (13) | 0.0242 (3) | |
C2 | 0.78972 (15) | 0.32772 (9) | 0.63022 (13) | 0.0229 (3) | |
C3 | 0.78870 (16) | 0.23434 (9) | 0.64445 (13) | 0.0250 (3) | |
C4 | 0.57229 (15) | 0.22878 (10) | 0.54306 (14) | 0.0248 (3) | |
C5 | 0.45950 (15) | 0.36105 (10) | 0.47751 (14) | 0.0265 (3) | |
H5A | 0.4319 | 0.3274 | 0.4088 | 0.032* | |
H5B | 0.4890 | 0.4182 | 0.4508 | 0.032* | |
C6 | 0.34165 (17) | 0.37168 (11) | 0.55619 (16) | 0.0341 (4) | |
H6A | 0.2705 | 0.4026 | 0.5152 | 0.051* | |
H6B | 0.3690 | 0.4042 | 0.6249 | 0.051* | |
H6C | 0.3092 | 0.3151 | 0.5794 | 0.051* | |
C7 | 0.67507 (17) | 0.09673 (10) | 0.62395 (15) | 0.0303 (4) | |
H7A | 0.5820 | 0.0766 | 0.6301 | 0.036* | |
H7B | 0.7216 | 0.0837 | 0.6977 | 0.036* | |
C8 | 0.7422 (2) | 0.04915 (11) | 0.52713 (19) | 0.0415 (4) | |
H8A | 0.7466 | −0.0121 | 0.5458 | 0.062* | |
H8B | 0.8325 | 0.0715 | 0.5175 | 0.062* | |
H8C | 0.6911 | 0.0572 | 0.4553 | 0.062* | |
C9 | 0.90368 (16) | 0.36954 (10) | 0.66047 (13) | 0.0250 (3) | |
H9 | 0.9718 | 0.3342 | 0.6923 | 0.030* | |
C10 | 0.93689 (16) | 0.45823 (10) | 0.65184 (13) | 0.0254 (3) | |
H10 | 0.8741 | 0.4981 | 0.6216 | 0.031* | |
C11 | 1.05873 (16) | 0.48485 (10) | 0.68724 (14) | 0.0258 (3) | |
H11 | 1.1170 | 0.4415 | 0.7155 | 0.031* | |
C12 | 1.11166 (16) | 0.57152 (10) | 0.68749 (13) | 0.0246 (3) | |
C13 | 1.24183 (16) | 0.58518 (10) | 0.72991 (13) | 0.0252 (3) | |
C14 | 1.29543 (16) | 0.66804 (10) | 0.73119 (14) | 0.0275 (3) | |
H14 | 1.3836 | 0.6774 | 0.7589 | 0.033* | |
C15 | 1.21964 (17) | 0.73610 (10) | 0.69203 (15) | 0.0294 (4) | |
H15 | 1.2566 | 0.7922 | 0.6926 | 0.035* | |
C16 | 1.08972 (17) | 0.72399 (10) | 0.65159 (14) | 0.0288 (3) | |
C17 | 1.03685 (16) | 0.64216 (10) | 0.64830 (14) | 0.0262 (3) | |
H17 | 0.9490 | 0.6336 | 0.6192 | 0.031* | |
C18 | 1.44150 (17) | 0.52479 (11) | 0.81125 (16) | 0.0328 (4) | |
H18A | 1.4763 | 0.4690 | 0.8361 | 0.049* | |
H18B | 1.4415 | 0.5643 | 0.8770 | 0.049* | |
H18C | 1.4978 | 0.5481 | 0.7504 | 0.049* | |
C19 | 0.89413 (19) | 0.78713 (12) | 0.56997 (19) | 0.0415 (4) | |
H19A | 0.8576 | 0.8436 | 0.5503 | 0.062* | |
H19B | 0.8368 | 0.7592 | 0.6264 | 0.062* | |
H19C | 0.8983 | 0.7518 | 0.5002 | 0.062* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0323 (2) | 0.0271 (2) | 0.0610 (3) | −0.00414 (17) | −0.0128 (2) | −0.0060 (2) |
O1 | 0.0306 (6) | 0.0158 (5) | 0.0640 (8) | 0.0014 (5) | −0.0106 (6) | 0.0012 (5) |
O2 | 0.0364 (7) | 0.0202 (5) | 0.0534 (8) | 0.0041 (5) | −0.0167 (6) | 0.0012 (5) |
O3 | 0.0260 (6) | 0.0242 (6) | 0.0465 (7) | −0.0029 (5) | −0.0060 (5) | −0.0024 (5) |
O4 | 0.0380 (7) | 0.0223 (6) | 0.0629 (9) | −0.0045 (5) | −0.0123 (6) | 0.0066 (6) |
N1 | 0.0214 (6) | 0.0185 (6) | 0.0287 (6) | −0.0005 (5) | −0.0028 (5) | 0.0002 (5) |
N2 | 0.0250 (7) | 0.0158 (6) | 0.0307 (7) | −0.0010 (5) | −0.0004 (5) | 0.0005 (5) |
C1 | 0.0230 (8) | 0.0185 (7) | 0.0312 (8) | −0.0009 (6) | −0.0002 (6) | 0.0016 (6) |
C2 | 0.0249 (8) | 0.0167 (7) | 0.0270 (7) | 0.0005 (6) | −0.0025 (6) | −0.0014 (5) |
C3 | 0.0274 (8) | 0.0186 (7) | 0.0288 (8) | 0.0006 (6) | −0.0017 (6) | −0.0006 (6) |
C4 | 0.0244 (8) | 0.0200 (7) | 0.0300 (8) | −0.0015 (6) | 0.0008 (6) | −0.0011 (6) |
C5 | 0.0242 (8) | 0.0241 (7) | 0.0309 (8) | 0.0020 (6) | −0.0053 (6) | 0.0034 (6) |
C6 | 0.0285 (9) | 0.0318 (9) | 0.0419 (10) | 0.0039 (7) | −0.0002 (7) | −0.0008 (7) |
C7 | 0.0322 (9) | 0.0160 (7) | 0.0427 (9) | −0.0018 (6) | 0.0037 (7) | 0.0029 (6) |
C8 | 0.0402 (10) | 0.0252 (8) | 0.0594 (12) | 0.0003 (7) | 0.0068 (9) | −0.0097 (8) |
C9 | 0.0255 (8) | 0.0202 (7) | 0.0293 (8) | 0.0011 (6) | −0.0020 (6) | −0.0024 (6) |
C10 | 0.0262 (8) | 0.0202 (7) | 0.0299 (8) | −0.0005 (6) | −0.0010 (6) | −0.0021 (6) |
C11 | 0.0270 (8) | 0.0207 (7) | 0.0298 (8) | −0.0001 (6) | 0.0009 (6) | −0.0033 (6) |
C12 | 0.0260 (8) | 0.0220 (7) | 0.0260 (7) | −0.0039 (6) | 0.0029 (6) | −0.0045 (6) |
C13 | 0.0254 (8) | 0.0228 (7) | 0.0275 (8) | −0.0009 (6) | 0.0030 (6) | −0.0036 (6) |
C14 | 0.0254 (8) | 0.0271 (8) | 0.0300 (8) | −0.0066 (6) | 0.0018 (6) | −0.0054 (6) |
C15 | 0.0313 (9) | 0.0226 (7) | 0.0345 (8) | −0.0091 (6) | 0.0034 (7) | −0.0039 (6) |
C16 | 0.0328 (9) | 0.0224 (7) | 0.0314 (8) | −0.0021 (6) | 0.0013 (7) | 0.0000 (6) |
C17 | 0.0251 (8) | 0.0230 (7) | 0.0305 (8) | −0.0038 (6) | −0.0003 (6) | −0.0008 (6) |
C18 | 0.0264 (8) | 0.0320 (9) | 0.0398 (9) | −0.0031 (7) | −0.0051 (7) | 0.0009 (7) |
C19 | 0.0365 (10) | 0.0292 (9) | 0.0587 (12) | −0.0017 (7) | −0.0097 (9) | 0.0094 (8) |
S1—C4 | 1.6516 (16) | C8—H8A | 0.9800 |
O1—C1 | 1.2160 (19) | C8—H8B | 0.9800 |
O2—C3 | 1.2207 (19) | C8—H8C | 0.9800 |
O3—C13 | 1.3582 (19) | C9—C10 | 1.427 (2) |
O3—C18 | 1.430 (2) | C9—H9 | 0.9500 |
O4—C16 | 1.368 (2) | C10—C11 | 1.351 (2) |
O4—C19 | 1.422 (2) | C10—H10 | 0.9500 |
N1—C4 | 1.3815 (19) | C11—C12 | 1.453 (2) |
N1—C1 | 1.4065 (19) | C11—H11 | 0.9500 |
N1—C5 | 1.4791 (19) | C12—C17 | 1.405 (2) |
N2—C4 | 1.385 (2) | C12—C13 | 1.407 (2) |
N2—C3 | 1.396 (2) | C13—C14 | 1.400 (2) |
N2—C7 | 1.4852 (19) | C14—C15 | 1.379 (2) |
C1—C2 | 1.461 (2) | C14—H14 | 0.9500 |
C2—C9 | 1.360 (2) | C15—C16 | 1.394 (2) |
C2—C3 | 1.465 (2) | C15—H15 | 0.9500 |
C5—C6 | 1.514 (2) | C16—C17 | 1.383 (2) |
C5—H5A | 0.9900 | C17—H17 | 0.9500 |
C5—H5B | 0.9900 | C18—H18A | 0.9800 |
C6—H6A | 0.9800 | C18—H18B | 0.9800 |
C6—H6B | 0.9800 | C18—H18C | 0.9800 |
C6—H6C | 0.9800 | C19—H19A | 0.9800 |
C7—C8 | 1.512 (2) | C19—H19B | 0.9800 |
C7—H7A | 0.9900 | C19—H19C | 0.9800 |
C7—H7B | 0.9900 | ||
C13—O3—C18 | 118.65 (12) | H8A—C8—H8C | 109.5 |
C16—O4—C19 | 117.25 (14) | H8B—C8—H8C | 109.5 |
C4—N1—C1 | 124.56 (13) | C2—C9—C10 | 130.09 (15) |
C4—N1—C5 | 119.26 (13) | C2—C9—H9 | 115.0 |
C1—N1—C5 | 116.18 (12) | C10—C9—H9 | 115.0 |
C4—N2—C3 | 124.38 (13) | C11—C10—C9 | 119.24 (15) |
C4—N2—C7 | 119.65 (13) | C11—C10—H10 | 120.4 |
C3—N2—C7 | 115.81 (13) | C9—C10—H10 | 120.4 |
O1—C1—N1 | 119.92 (14) | C10—C11—C12 | 128.08 (15) |
O1—C1—C2 | 123.75 (14) | C10—C11—H11 | 116.0 |
N1—C1—C2 | 116.32 (13) | C12—C11—H11 | 116.0 |
C9—C2—C1 | 123.71 (14) | C17—C12—C13 | 119.00 (14) |
C9—C2—C3 | 117.04 (14) | C17—C12—C11 | 122.30 (15) |
C1—C2—C3 | 119.24 (13) | C13—C12—C11 | 118.70 (14) |
O2—C3—N2 | 119.86 (14) | O3—C13—C14 | 123.75 (15) |
O2—C3—C2 | 123.26 (14) | O3—C13—C12 | 116.31 (13) |
N2—C3—C2 | 116.89 (13) | C14—C13—C12 | 119.94 (15) |
N1—C4—N2 | 117.14 (13) | C15—C14—C13 | 119.73 (15) |
N1—C4—S1 | 121.84 (12) | C15—C14—H14 | 120.1 |
N2—C4—S1 | 121.01 (11) | C13—C14—H14 | 120.1 |
N1—C5—C6 | 111.71 (13) | C14—C15—C16 | 121.12 (14) |
N1—C5—H5A | 109.3 | C14—C15—H15 | 119.4 |
C6—C5—H5A | 109.3 | C16—C15—H15 | 119.4 |
N1—C5—H5B | 109.3 | O4—C16—C17 | 125.20 (16) |
C6—C5—H5B | 109.3 | O4—C16—C15 | 115.32 (14) |
H5A—C5—H5B | 107.9 | C17—C16—C15 | 119.48 (15) |
C5—C6—H6A | 109.5 | C16—C17—C12 | 120.71 (15) |
C5—C6—H6B | 109.5 | C16—C17—H17 | 119.6 |
H6A—C6—H6B | 109.5 | C12—C17—H17 | 119.6 |
C5—C6—H6C | 109.5 | O3—C18—H18A | 109.5 |
H6A—C6—H6C | 109.5 | O3—C18—H18B | 109.5 |
H6B—C6—H6C | 109.5 | H18A—C18—H18B | 109.5 |
N2—C7—C8 | 111.72 (14) | O3—C18—H18C | 109.5 |
N2—C7—H7A | 109.3 | H18A—C18—H18C | 109.5 |
C8—C7—H7A | 109.3 | H18B—C18—H18C | 109.5 |
N2—C7—H7B | 109.3 | O4—C19—H19A | 109.5 |
C8—C7—H7B | 109.3 | O4—C19—H19B | 109.5 |
H7A—C7—H7B | 107.9 | H19A—C19—H19B | 109.5 |
C7—C8—H8A | 109.5 | O4—C19—H19C | 109.5 |
C7—C8—H8B | 109.5 | H19A—C19—H19C | 109.5 |
H8A—C8—H8B | 109.5 | H19B—C19—H19C | 109.5 |
C7—C8—H8C | 109.5 | ||
C4—N1—C1—O1 | −172.42 (15) | C4—N2—C7—C8 | 88.82 (18) |
C5—N1—C1—O1 | 6.6 (2) | C3—N2—C7—C8 | −86.77 (18) |
C4—N1—C1—C2 | 8.2 (2) | C1—C2—C9—C10 | −2.7 (3) |
C5—N1—C1—C2 | −172.73 (13) | C3—C2—C9—C10 | 176.85 (15) |
O1—C1—C2—C9 | −11.3 (3) | C2—C9—C10—C11 | −179.44 (16) |
N1—C1—C2—C9 | 167.98 (14) | C9—C10—C11—C12 | −179.07 (15) |
O1—C1—C2—C3 | 169.12 (15) | C10—C11—C12—C17 | 0.0 (3) |
N1—C1—C2—C3 | −11.6 (2) | C10—C11—C12—C13 | 179.19 (15) |
C4—N2—C3—O2 | −173.69 (15) | C18—O3—C13—C14 | −0.2 (2) |
C7—N2—C3—O2 | 1.7 (2) | C18—O3—C13—C12 | 179.70 (14) |
C4—N2—C3—C2 | 6.8 (2) | C17—C12—C13—O3 | 179.26 (13) |
C7—N2—C3—C2 | −177.84 (13) | C11—C12—C13—O3 | 0.1 (2) |
C9—C2—C3—O2 | 5.6 (2) | C17—C12—C13—C14 | −0.8 (2) |
C1—C2—C3—O2 | −174.83 (15) | C11—C12—C13—C14 | −179.99 (14) |
C9—C2—C3—N2 | −174.93 (14) | O3—C13—C14—C15 | −179.33 (14) |
C1—C2—C3—N2 | 4.7 (2) | C12—C13—C14—C15 | 0.7 (2) |
C1—N1—C4—N2 | 2.4 (2) | C13—C14—C15—C16 | 0.4 (2) |
C5—N1—C4—N2 | −176.56 (13) | C19—O4—C16—C17 | −3.6 (3) |
C1—N1—C4—S1 | −177.59 (12) | C19—O4—C16—C15 | 176.54 (16) |
C5—N1—C4—S1 | 3.42 (19) | C14—C15—C16—O4 | 178.46 (15) |
C3—N2—C4—N1 | −10.5 (2) | C14—C15—C16—C17 | −1.4 (2) |
C7—N2—C4—N1 | 174.31 (13) | O4—C16—C17—C12 | −178.52 (15) |
C3—N2—C4—S1 | 169.52 (12) | C15—C16—C17—C12 | 1.3 (2) |
C7—N2—C4—S1 | −5.67 (19) | C13—C12—C17—C16 | −0.2 (2) |
C4—N1—C5—C6 | 82.80 (17) | C11—C12—C17—C16 | 178.91 (15) |
C1—N1—C5—C6 | −96.28 (16) |
Experimental details
Crystal data | |
Chemical formula | C19H22N2O4S |
Mr | 374.45 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 140 |
a, b, c (Å) | 10.0519 (2), 15.5942 (3), 11.5920 (2) |
β (°) | 90.813 (1) |
V (Å3) | 1816.88 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.21 |
Crystal size (mm) | 0.35 × 0.25 × 0.15 |
Data collection | |
Diffractometer | Bruker SMART APEX diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.932, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12384, 4124, 3351 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.039, 0.119, 1.02 |
No. of reflections | 4124 |
No. of parameters | 239 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.38, −0.31 |
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).
Acknowledgements
We thank King Abdul Aziz University and the University of Malaya for supporting this study.
References
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