Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Previous article
Next article
Previous article
Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Next article

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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 7| July 2012| Page o2134
https://doi.org/10.1107/S1600536812026189

2-Methyl­sulfanyl-9H-1,3,4-thia­diazolo[2,3-b]quinazolin-9-one

Adel S. El-Azab,a,b‡ Alaa A.-M. Abdel-Aziz,a,c Ibrahim A. Al-Swaidan,a Seik Weng Ngd,e and Edward R. T. Tiekinkd*

aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, bDepartment of Organic Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt, cDepartment of Medicinal Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura 35516, Egypt, dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and eChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 9 June 2012; accepted 9 June 2012; online 20 June 2012)

In the title compound, C10H7N3OS2, the 16 non-H atoms are almost planar (r.m.s. deviation = 0.037 Å) and the S-bound methyl group is syn to the ketone O atom. In the crystal, centrosymmetrically related mol­ecules are connected by pairs of C—H⋯O inter­actions between the ketone O and methyl H atoms. The dimeric aggregates are connected into a linear supra­molecular chain along the b axis via π–π inter­actions occurring between the five-membered and benzene rings [centroid–centroid distance = 3.6123 (9) Å]. The chains assemble into layers in the bc plane via S⋯S inter­actions involving the endocyclic S atoms [S⋯S = 3.4607 (6) and 3.4792 (6) Å].

Related literature

For recent studies on the synthesis and biological properties of quinazoline-4(3H)-one derivatives, see: El-Azab & ElTahir (2012[El-Azab, A. S. & ElTahir, K. H. (2012). Bioorg. Med. Chem. Lett. 22, 1879-1885.]); El-Azab et al. (2011[El-Azab, A. S. & ElTahir, K. H. & Attia, S. M. (2011). Monatsh. Chem. 142, 837-848.]). For the synthesis and anti-microbial activity of the title compound, see: El-Azab (2007[El-Azab, A. S. (2007). Phosphorus Sulfur Silicon, 182, 333-348.]).

[Scheme 1]

Experimental

Crystal data

  • C10H7N3OS2

  • Mr = 249.31

  • Monoclinic, P 21 /c

  • a = 11.8193 (4) Å

  • b = 4.9841 (2) Å

  • c = 17.4985 (6) Å

  • β = 91.453 (3)°

  • V = 1030.48 (6) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 4.53 mm−1

  • T = 100 K

  • 0.30 × 0.10 × 0.03 mm
Data collection

  • Agilent SuperNova Dual diffractometer with an Atlas detector

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012[Agilent (2012). CrysAlis PRO. Agilent Technologies, Yarnton, England.]) Tmin = 0.344, Tmax = 0.876

  • 3781 measured reflections

  • 2110 independent reflections

  • 1937 reflections with I > 2σ(I)

  • Rint = 0.018
Refinement

  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.082

  • S = 1.09

  • 2110 reflections

  • 145 parameters

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.27 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C10—H10A⋯O1i 0.98 2.32 3.170 (2) 145
Symmetry code: (i) -x+1, -y+2, -z+1.

Data collection: CrysAlis PRO (Agilent, 2012[Agilent (2012). CrysAlis PRO. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536812026189/hb6843sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812026189/hb6843Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812026189/hb6843Isup3.cml

checkCIF report


Comment top

Quinazoline-4(3H)-one derivatives attract interest owing to their putative biological activity (El-Azab & ElTahir, 2012; El-Azab et al., 2011). The title compound, 2-(methylthio)-5H-[1,3,4]thiadiazolo[2,3-b]quinazolin-5-one (I), has been synthesized previously and evaluated for its anti-microbial activity (El-Azab, 2007). Herein, we describe its crystal structure determination.

The 16 non-hydrogen atoms in (I), Fig. 1, are planar with the r.m.s. deviation being 0.037 Å. The maximum deviations from the least-squares plane are 0.068 (1) Å for the ketone-O1 atom and -0.065 (2) Å for the methyl-C10 atom. The S-bound methyl group is syn to the ketone-O1 atom.

In the crystal packing, centrosymmetrically related molecules are connected by C—H···O interactions between the ketone-O and methyl-H atoms, Table 1, via a 16-membered {···HCSCN2CO}2 synthon, Fig. 2. The dimeric aggregates are connected into a linear supramolecular chain along the b axis via π—π interactions occurring between the five-membered and benzene rings [inter-centroid distance = 3.6123 (9) Å, angle of inclination = 2.09 (7)° for symmetry operation: x, 1 + y, z]. The chains assemble into layers in the bc plane via S···S interactions involving the endocyclic-S1 atoms whereby each S1 atom forms two such interactions [S1···S1i = 3.4607 (6) Å for symmetry operation i: 2 - x,2 - y,1 - z; and S1···S1ii = 3.4792 (6) Å for ii: 2 - x, 1 - y, 1 - z]. Layers stack along the a axis without specific interactions between them, Fig. 3.

Related literature top

For recent studies on the synthesis and biological properties of quinazoline-4(3H)-one derivatives, see: El-Azab & ElTahir (2012); El-Azab et al. (2011). For the synthesis and anti-microbial activity of the title compound, see: El-Azab (2007).

Experimental top

A mixture of 2-mercapto-5H-[1,3,4]thiadiazolo[2,3-b]quinazolin-5-one (470 mg, 2 mmol) and methyliodide (2.1 mmol) in acetone (10 ml) containing anhydrous potassium carbonate (300 mg) was stirred at room temperature for 12 h. The reaction mixture was filtered, the solvent removed under reduced pressure and the solid obtained was dried and recrystallized from ethanol. Yield 88%. 1H NMR (CDCl3): δ 8.42 (d, 1H, J = 7.5 Hz), 7.79 (t, 1H, J = 7.0 Hz), 7.63 (d, 1H, J = 8.0 Hz), 7.49 (t, 1H, J = 7.0 Hz), 2.84 (s, 3H) p.p.m.. 13C NMR (CDCl3): δ = 15.3, 118.9, 126.2, 127.6, 134.8, 147.2, 156.2, 157.1, 158.5 p.p.m..

Refinement top

Carbon-bound H-atoms were placed in calculated positions [C—H = 0.95 to 0.98 Å, Uiso(H) = 1.2–1.5Ueq(C)] and were included in the refinement in the riding model approximation.

Structure description top

Quinazoline-4(3H)-one derivatives attract interest owing to their putative biological activity (El-Azab & ElTahir, 2012; El-Azab et al., 2011). The title compound, 2-(methylthio)-5H-[1,3,4]thiadiazolo[2,3-b]quinazolin-5-one (I), has been synthesized previously and evaluated for its anti-microbial activity (El-Azab, 2007). Herein, we describe its crystal structure determination.

The 16 non-hydrogen atoms in (I), Fig. 1, are planar with the r.m.s. deviation being 0.037 Å. The maximum deviations from the least-squares plane are 0.068 (1) Å for the ketone-O1 atom and -0.065 (2) Å for the methyl-C10 atom. The S-bound methyl group is syn to the ketone-O1 atom.

In the crystal packing, centrosymmetrically related molecules are connected by C—H···O interactions between the ketone-O and methyl-H atoms, Table 1, via a 16-membered {···HCSCN2CO}2 synthon, Fig. 2. The dimeric aggregates are connected into a linear supramolecular chain along the b axis via π—π interactions occurring between the five-membered and benzene rings [inter-centroid distance = 3.6123 (9) Å, angle of inclination = 2.09 (7)° for symmetry operation: x, 1 + y, z]. The chains assemble into layers in the bc plane via S···S interactions involving the endocyclic-S1 atoms whereby each S1 atom forms two such interactions [S1···S1i = 3.4607 (6) Å for symmetry operation i: 2 - x,2 - y,1 - z; and S1···S1ii = 3.4792 (6) Å for ii: 2 - x, 1 - y, 1 - z]. Layers stack along the a axis without specific interactions between them, Fig. 3.

For recent studies on the synthesis and biological properties of quinazoline-4(3H)-one derivatives, see: El-Azab & ElTahir (2012); El-Azab et al. (2011). For the synthesis and anti-microbial activity of the title compound, see: El-Azab (2007).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. A view of the linear supramolecular chain along the b axis in (I). The C—H···O and π—π interactions are shown as orange and purple dashed lines respectively.
[Figure 3] Fig. 3. A view in projection down the b axis of the unit-cell contents for (I). The C—H···O, π—π and S···S interactions are shown as orange, purple and blue dashed lines respectively.
2-Methylsulfanyl-9H-1,3,4-thiadiazolo[2,3-b]quinazolin-9-one top
Crystal data top
C10H7N3OS2F(000) = 512
Mr = 249.31Dx = 1.607 Mg m−3
Monoclinic, P21/cCu Kα radiation, λ = 1.54184 Å
Hall symbol: -P 2ybcCell parameters from 2166 reflections
a = 11.8193 (4) Åθ = 3.7–76.5°
b = 4.9841 (2) ŵ = 4.53 mm−1
c = 17.4985 (6) ÅT = 100 K
β = 91.453 (3)°Prism, colourless
V = 1030.48 (6) Å30.30 × 0.10 × 0.03 mm
Z = 4
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector		2110 independent reflections
Radiation source: SuperNova (Cu) X-ray Source1937 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.018
Detector resolution: 10.4041 pixels mm-1θmax = 76.7°, θmin = 3.7°
ω scanh = −12→14
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)		k = −5→6
Tmin = 0.344, Tmax = 0.876l = −15→21
3781 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)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.082H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0457P)2 + 0.3686P]
where P = (Fo2 + 2Fc2)/3
2110 reflections(Δ/σ)max = 0.001
145 parametersΔρmax = 0.36 e Å−3
0 restraintsΔρmin = −0.27 e Å−3
Crystal data top
C10H7N3OS2V = 1030.48 (6) Å3
Mr = 249.31Z = 4
Monoclinic, P21/cCu Kα radiation
a = 11.8193 (4) ŵ = 4.53 mm−1
b = 4.9841 (2) ÅT = 100 K
c = 17.4985 (6) Å0.30 × 0.10 × 0.03 mm
β = 91.453 (3)°
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector		2110 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)		1937 reflections with I > 2σ(I)
Tmin = 0.344, Tmax = 0.876Rint = 0.018
3781 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.082H-atom parameters constrained
S = 1.09Δρmax = 0.36 e Å−3
2110 reflectionsΔρmin = −0.27 e Å−3
145 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.90968 (3)0.75129 (8)0.46619 (2)0.01702 (12)
S20.76245 (3)1.12015 (8)0.55613 (2)0.01660 (12)
N10.90012 (11)0.3645 (3)0.35873 (8)0.0160 (3)
N20.72981 (11)0.5607 (3)0.40394 (7)0.0145 (3)
N30.68915 (11)0.7516 (3)0.45394 (7)0.0160 (3)
O10.55197 (9)0.4218 (3)0.36566 (7)0.0217 (3)
C10.65417 (13)0.4007 (3)0.36022 (9)0.0159 (3)
C20.71312 (13)0.2152 (3)0.31034 (9)0.0153 (3)
C30.64945 (13)0.0467 (4)0.26154 (9)0.0183 (3)
H30.56910.05330.26160.022*
C40.70332 (14)−0.1282 (4)0.21351 (9)0.0196 (3)
H40.6602−0.24290.18060.024*
C50.82196 (14)−0.1368 (3)0.21325 (9)0.0192 (3)
H50.8589−0.25600.17960.023*
C60.88539 (13)0.0261 (3)0.26135 (9)0.0179 (3)
H60.96570.01730.26090.021*
C70.83228 (13)0.2050 (3)0.31091 (9)0.0149 (3)
C80.84595 (12)0.5289 (3)0.40102 (8)0.0149 (3)
C90.77423 (13)0.8644 (3)0.48930 (9)0.0152 (3)
C100.61018 (14)1.1556 (4)0.55743 (10)0.0211 (3)
H10A0.59031.29650.59380.032*
H10B0.57620.98540.57300.032*
H10C0.58151.20410.50620.032*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.01263 (19)0.0180 (2)0.0204 (2)−0.00013 (13)−0.00028 (14)−0.00389 (14)
S20.0170 (2)0.0176 (2)0.0151 (2)0.00105 (14)−0.00022 (14)−0.00248 (14)
N10.0136 (6)0.0176 (7)0.0167 (6)0.0001 (5)0.0003 (5)−0.0019 (5)
N20.0124 (6)0.0179 (7)0.0133 (6)0.0031 (5)0.0007 (5)−0.0011 (5)
N30.0161 (6)0.0180 (7)0.0139 (6)0.0031 (5)0.0001 (5)−0.0018 (5)
O10.0118 (5)0.0294 (7)0.0239 (6)0.0024 (5)−0.0007 (4)−0.0067 (5)
C10.0148 (7)0.0191 (7)0.0138 (7)0.0014 (6)−0.0011 (6)−0.0006 (6)
C20.0151 (7)0.0176 (7)0.0131 (7)0.0011 (6)−0.0001 (5)0.0006 (6)
C30.0146 (7)0.0227 (8)0.0176 (7)0.0013 (7)−0.0018 (6)−0.0009 (6)
C40.0190 (8)0.0219 (8)0.0177 (8)0.0007 (6)−0.0041 (6)−0.0031 (6)
C50.0204 (8)0.0207 (8)0.0166 (7)0.0037 (6)0.0012 (6)−0.0032 (6)
C60.0135 (7)0.0206 (8)0.0195 (7)0.0022 (6)0.0013 (6)−0.0013 (6)
C70.0149 (7)0.0160 (7)0.0139 (7)−0.0004 (6)0.0001 (5)0.0017 (6)
C80.0127 (7)0.0159 (7)0.0160 (7)−0.0008 (6)−0.0005 (5)0.0023 (6)
C90.0155 (7)0.0160 (7)0.0141 (7)0.0019 (6)0.0005 (5)0.0014 (6)
C100.0178 (7)0.0261 (9)0.0194 (8)0.0048 (7)0.0015 (6)−0.0032 (7)
Geometric parameters (Å, º) top
S1—C81.7473 (16)C2—C71.409 (2)
S1—C91.7542 (16)C3—C41.378 (2)
S2—C91.7378 (16)C3—H30.9500
S2—C101.8091 (17)C4—C51.403 (2)
N1—C81.286 (2)C4—H40.9500
N1—C71.393 (2)C5—C61.378 (2)
N2—C81.3840 (18)C5—H50.9500
N2—N31.3866 (18)C6—C71.403 (2)
N2—C11.409 (2)C6—H60.9500
N3—C91.296 (2)C10—H10A0.9800
O1—C11.2186 (19)C10—H10B0.9800
C1—C21.461 (2)C10—H10C0.9800
C2—C31.403 (2)
C8—S1—C988.48 (7)C6—C5—H5119.7
C9—S2—C10100.19 (8)C4—C5—H5119.7
C8—N1—C7114.96 (13)C5—C6—C7120.47 (14)
C8—N2—N3117.51 (13)C5—C6—H6119.8
C8—N2—C1122.09 (13)C7—C6—H6119.8
N3—N2—C1120.37 (12)N1—C7—C6118.30 (14)
C9—N3—N2108.78 (13)N1—C7—C2122.93 (14)
O1—C1—N2121.69 (14)C6—C7—C2118.77 (14)
O1—C1—C2126.16 (15)N1—C8—N2127.10 (14)
N2—C1—C2112.15 (13)N1—C8—S1124.55 (12)
C3—C2—C7120.23 (14)N2—C8—S1108.35 (11)
C3—C2—C1119.08 (14)N3—C9—S2124.42 (12)
C7—C2—C1120.69 (14)N3—C9—S1116.88 (12)
C4—C3—C2120.06 (15)S2—C9—S1118.69 (9)
C4—C3—H3120.0S2—C10—H10A109.5
C2—C3—H3120.0S2—C10—H10B109.5
C3—C4—C5119.90 (15)H10A—C10—H10B109.5
C3—C4—H4120.0S2—C10—H10C109.5
C5—C4—H4120.0H10A—C10—H10C109.5
C6—C5—C4120.56 (15)H10B—C10—H10C109.5
C8—N2—N3—C9−0.24 (19)C3—C2—C7—N1−179.16 (15)
C1—N2—N3—C9177.60 (13)C1—C2—C7—N10.9 (2)
C8—N2—C1—O1176.66 (15)C3—C2—C7—C60.7 (2)
N3—N2—C1—O1−1.1 (2)C1—C2—C7—C6−179.20 (15)
C8—N2—C1—C2−3.1 (2)C7—N1—C8—N20.4 (2)
N3—N2—C1—C2179.13 (13)C7—N1—C8—S1179.87 (11)
O1—C1—C2—C31.9 (3)N3—N2—C8—N1−179.87 (15)
N2—C1—C2—C3−178.30 (14)C1—N2—C8—N12.3 (2)
O1—C1—C2—C7−178.17 (16)N3—N2—C8—S10.61 (17)
N2—C1—C2—C71.6 (2)C1—N2—C8—S1−177.18 (12)
C7—C2—C3—C4−0.5 (2)C9—S1—C8—N1179.88 (15)
C1—C2—C3—C4179.44 (15)C9—S1—C8—N2−0.59 (11)
C2—C3—C4—C5−0.3 (3)N2—N3—C9—S2178.77 (11)
C3—C4—C5—C60.8 (3)N2—N3—C9—S1−0.27 (17)
C4—C5—C6—C7−0.5 (3)C10—S2—C9—N30.76 (16)
C8—N1—C7—C6178.13 (15)C10—S2—C9—S1179.79 (10)
C8—N1—C7—C2−2.0 (2)C8—S1—C9—N30.53 (13)
C5—C6—C7—N1179.67 (15)C8—S1—C9—S2−178.57 (10)
C5—C6—C7—C2−0.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O1i0.982.323.170 (2)145
Symmetry code: (i) −x+1, −y+2, −z+1.

Experimental details

Crystal data
Chemical formulaC10H7N3OS2
Mr249.31
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)11.8193 (4), 4.9841 (2), 17.4985 (6)
β (°) 91.453 (3)
V (Å3)1030.48 (6)
Z4
Radiation typeCu Kα
µ (mm−1)4.53
Crystal size (mm)0.30 × 0.10 × 0.03
Data collection
DiffractometerAgilent SuperNova Dual
diffractometer with an Atlas detector
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2012)
Tmin, Tmax0.344, 0.876
No. of measured, independent and
observed [I > 2σ(I)] reflections		3781, 2110, 1937
Rint0.018
(sin θ/λ)max (Å−1)0.631
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.082, 1.09
No. of reflections2110
No. of parameters145
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.36, −0.27

Computer programs: CrysAlis PRO (Agilent, 2012), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O1i0.982.323.170 (2)145
Symmetry code: (i) −x+1, −y+2, −z+1.
 

Footnotes

‡Additional correspondence author, e-mail: adelazaba@yahoo.com.

Acknowledgements

We thank the Deanship of Scientific Research and the Research Center of the College of Pharmacy, King Saud University. We also thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (UM.C/HIR/MOHE/SC/12).

References

First citationAgilent (2012). CrysAlis PRO. Agilent Technologies, Yarnton, England.  Google Scholar
 First citationBrandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
 First citationEl-Azab, A. S. (2007). Phosphorus Sulfur Silicon, 182, 333–348.  CAS Google Scholar
 First citationEl-Azab, A. S. & ElTahir, K. H. (2012). Bioorg. Med. Chem. Lett. 22, 1879–1885.  Web of Science CAS PubMed Google Scholar
 First citationEl-Azab, A. S. & ElTahir, K. H. & Attia, S. M. (2011). Monatsh. Chem. 142, 837–848.  CAS Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  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 logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 7| July 2012| Page o2134
https://doi.org/10.1107/S1600536812026189
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS