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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 9| September 2015| Pages o677-o678
https://doi.org/10.1107/S2056989015014061

Crystal structure of methyl 2-(7-hy­dr­oxy-2-oxo-2H-chromen-4-yl)acetate

CROSSMARK_Color_square_no_text.svg
Sammer Yousuf,a* Shafqat Hussain,b Khalid Mohammed Khan,a Muhammad Shabeera and Shahnaz Perveenc

aH.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan, bDepartment of Chemistry, Karakoram International University, Gilgit, Pakistan, and cPCSIR Laboratories, Karachi, Pakistan
*Correspondence e-mail: dr.sammer.yousuf@gmail.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 22 July 2015; accepted 25 July 2015; online 22 August 2015)

In the title coumarin derivative, C12H10O5, the fused ring system is almost planar (r.m.s deviation = 0.016 Å). The Car—C—C=O torsion angle of the side chain is −8.4 (2)° In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, generating C(8) chains propagating in the [100] direction. The chains are cross-linked by weak C—H⋯O inter­actions, thereby generating undulating (001) sheets.

CCDC reference: 1415274

Similar articles

1. Related literature

For the applications and biological activities of coumarin derivatives, see: Vukovic et al. (2010[Vukovic, N., Sukdolak, S., Solujic, S. & Niciforovic, N. (2010). Arch. Pharm. Res. 33, 5-15.]); Basanagouda et al. (2009[Basanagouda, M., Kulkarni, M. V., Sharma, D., Gupta, V. K., Pranesha, Sandhyarani, P. & Rasal, V. P. (2009). J. Chem. Sci. 121, 485-495.]); Ahmad et al. (2008[Ahmad, H. B., Malana, M. A., Rama, N. H., Ilyas, S., Yousuf, M. & Khan, K. M. (2008). J. Chem. Soc. Pakistan, 30, 834-844.]); Abd Elhafez et al. (2003[Abd Elhafez, O. M., El Khrisy, E. E. D. A. M., Badria, F. & Fathy, A. E. D. M. (2003). Arch. Pharm. Res. 26, 686-696.]); Ukhov et al. (2001[Ukhov, S. V., Kon'shin, M. E. & Odegova, T. F. (2001). Pharm. Chem. J. 35, 364-365.]); Emmanuel-Giota et al. (2001[Emmanuel-Giota, A. A., Fylaktakidou, K. C., Litinas, K. E., Nicolaides, D. N. & Hadjipavlou-Litina, D. J. (2001). J. Heterocycl. Chem. 38, 717-722.]). For the crystal structure of a related compound, see: Subramanian et al. (1990[Subramanian, K., Sivakumar, K., Natarajan, S. & Parthasarathy, S. (1990). Acta Cryst. C46, 1661-1663.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C12H10O5

  • Mr = 234.20

  • Orthorhombic, P b c a

  • a = 13.0780 (12) Å

  • b = 7.2354 (7) Å

  • c = 22.262 (2) Å

  • V = 2106.5 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 273 K

  • 0.62 × 0.35 × 0.07 mm

2.2. Data collection

  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.932, Tmax = 0.992

  • 11536 measured reflections

  • 1958 independent reflections

  • 1669 reflections with I > 2σ(I)

  • Rint = 0.021

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.104

  • S = 1.03

  • 1958 reflections

  • 158 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O3—H3⋯O1i 0.96 (2) 1.74 (2) 2.7002 (17) 177 (2)
C7—H7A⋯O4ii 0.93 2.47 3.3320 (18) 155
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z].

Data collection: SMART (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

CCDC reference: 1415274

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2056989015014061/hb7469sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015014061/hb7469Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015014061/hb7469Isup3.cml

checkCIF report


Comment top

Coumarin, 2H-chromen-2-ones are naturally occurring aroma containing organic molecules belongs to benzopyrone (Ahmad et al., 2008) class of compounds. Coumarines known to have wide range of biological activities including antibacterial (Abd Elhafez et al., 2003, Ukhov et al., 2001), antitumour and anticoagulant (Emmanuel-Giota et al., 2001), antioxidant (Basanagouda et al., 2009) and antiinflammatory (Vukovic et al., 2010) properties. The literature has disclosed various methodologies to synthesize coumarine and their structural analogues. The title compound was synthesized during our attempts to maintained libraries of structural analogues of bioactive organic molecules.

The structure of title compound is similar to that of previously published Ethyl 7-hydroxy-4-coumarinacetate (Subramanian et al., 1990) with the difference that ethyl acetate moiety is replaced by methyl acetate chain (O4—O5/C10–C12)attached at C9 of central coumarin ring (Fig. 1).

The crystal structure features O3—H3···O1, and C7—H7A···O4 interactions to form (001) sheets (symmetry codes as in Table 2 and Fig. 2).

Related literature top

For the applications and biological activities of coumarin derivatives, see: Vukovic et al. (2010); Basanagouda et al. (2009); Ahmad et al. (2008); Abd Elhafez et al. (2003); Ukhov et al. (2001); Emmanuel-Giota et al. (2001). For the crystal structure of a related compound, see: Subramanian et al. (1990).

Experimental top

2-(7-Hydroxy-2-oxo-2H-chromen-4-yl) acetic acid (220 mg, 1 mmol) was dissolved in methanol (15 ml), and a few drops of sulfuric acid were added. The resulting reaction mixture was refluxed for 3 h. After the completion of the reaction as indicated by TLC, solvent was evaporated and the resulting reaction mixture was extracted with ethyl acetate, washed with sodium bicarbonate, brine and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure to afford crystals of title compound in 215 mg, 91% yield.

Refinement top

H atoms on methyl, methylene and phenyl were positioned geometrically with C—H = 0.96 Å (CH3), 0.97 Å (CH2) and 0.93 Å (CH phenyl) and constrained to ride on their parent atoms with Uiso(H)=1.5Ueq(CH3) and 1.2Ueq(CH and CH2). The H atoms on the oxygen (O–H= 0.96 (2) Å) was located in difference Fourier map and refined isotropically.

Structure description top

Coumarin, 2H-chromen-2-ones are naturally occurring aroma containing organic molecules belongs to benzopyrone (Ahmad et al., 2008) class of compounds. Coumarines known to have wide range of biological activities including antibacterial (Abd Elhafez et al., 2003, Ukhov et al., 2001), antitumour and anticoagulant (Emmanuel-Giota et al., 2001), antioxidant (Basanagouda et al., 2009) and antiinflammatory (Vukovic et al., 2010) properties. The literature has disclosed various methodologies to synthesize coumarine and their structural analogues. The title compound was synthesized during our attempts to maintained libraries of structural analogues of bioactive organic molecules.

The structure of title compound is similar to that of previously published Ethyl 7-hydroxy-4-coumarinacetate (Subramanian et al., 1990) with the difference that ethyl acetate moiety is replaced by methyl acetate chain (O4—O5/C10–C12)attached at C9 of central coumarin ring (Fig. 1).

The crystal structure features O3—H3···O1, and C7—H7A···O4 interactions to form (001) sheets (symmetry codes as in Table 2 and Fig. 2).

For the applications and biological activities of coumarin derivatives, see: Vukovic et al. (2010); Basanagouda et al. (2009); Ahmad et al. (2008); Abd Elhafez et al. (2003); Ukhov et al. (2001); Emmanuel-Giota et al. (2001). For the crystal structure of a related compound, see: Subramanian et al. (1990).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound I. Only hydrogen atoms involved in hydrogen bonding are shown.
Methyl 2-(7-hydroxy-2-oxo-2H-chromen-4-yl)acetate top
Crystal data top
C12H10O5Dx = 1.477 Mg m−3
Mr = 234.20Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PbcaCell parameters from 4477 reflections
a = 13.0780 (12) Åθ = 2.4–28.3°
b = 7.2354 (7) ŵ = 0.12 mm−1
c = 22.262 (2) ÅT = 273 K
V = 2106.5 (3) Å3Plate, yellow
Z = 80.62 × 0.35 × 0.07 mm
F(000) = 976
Data collection top
Bruker SMART APEX CCD
diffractometer		1958 independent reflections
Radiation source: fine-focus sealed tube1669 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ω scanθmax = 25.5°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		h = −15→14
Tmin = 0.932, Tmax = 0.992k = −8→8
11536 measured reflectionsl = −26→26
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0523P)2 + 0.6817P]
where P = (Fo2 + 2Fc2)/3
1958 reflections(Δ/σ)max < 0.001
158 parametersΔρmax = 0.28 e Å−3
0 restraintsΔρmin = −0.19 e Å−3
Crystal data top
C12H10O5V = 2106.5 (3) Å3
Mr = 234.20Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 13.0780 (12) ŵ = 0.12 mm−1
b = 7.2354 (7) ÅT = 273 K
c = 22.262 (2) Å0.62 × 0.35 × 0.07 mm
Data collection top
Bruker SMART APEX CCD
diffractometer		1958 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		1669 reflections with I > 2σ(I)
Tmin = 0.932, Tmax = 0.992Rint = 0.021
11536 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.28 e Å−3
1958 reflectionsΔρmin = −0.19 e Å−3
158 parameters
Special details top

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) top
xyzUiso*/Ueq
O10.42044 (8)0.1647 (2)0.43882 (5)0.0591 (4)
O20.58807 (7)0.16062 (15)0.44081 (4)0.0403 (3)
O30.94960 (9)0.1761 (2)0.45283 (6)0.0597 (4)
O40.64831 (11)0.23456 (17)0.22259 (5)0.0633 (4)
O50.64257 (9)−0.01095 (16)0.16271 (5)0.0525 (3)
C10.50365 (12)0.0564 (2)0.35141 (6)0.0440 (4)
H1A0.44320.03500.33050.053*
C20.49845 (11)0.1288 (2)0.41145 (7)0.0432 (4)
C30.68119 (11)0.12502 (18)0.41444 (6)0.0338 (3)
C40.76625 (11)0.1663 (2)0.44865 (6)0.0365 (3)
H4A0.75950.21410.48720.044*
C50.86154 (11)0.1347 (2)0.42403 (6)0.0397 (4)
C60.87047 (12)0.0581 (2)0.36677 (7)0.0414 (4)
H6A0.93490.03410.35090.050*
C70.78507 (11)0.01819 (19)0.33383 (6)0.0376 (3)
H7A0.7923−0.03280.29570.045*
C80.68705 (11)0.05257 (18)0.35637 (6)0.0336 (3)
C90.59328 (12)0.01865 (19)0.32448 (6)0.0375 (3)
C100.59598 (12)−0.0602 (2)0.26187 (6)0.0426 (4)
H10A0.6403−0.16770.26170.051*
H10B0.5278−0.10130.25120.051*
C110.63285 (11)0.0736 (2)0.21485 (6)0.0379 (3)
C120.67778 (15)0.1002 (3)0.11240 (8)0.0640 (5)
H12A0.68220.02440.07710.096*
H12B0.74400.15030.12140.096*
H12C0.63040.19930.10540.096*
H30.9369 (17)0.231 (3)0.4915 (11)0.091 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0375 (6)0.0935 (10)0.0463 (7)0.0056 (6)0.0053 (5)−0.0091 (6)
O20.0358 (6)0.0533 (6)0.0318 (5)0.0014 (5)0.0024 (4)−0.0043 (4)
O30.0379 (7)0.0923 (10)0.0489 (7)−0.0035 (6)−0.0062 (5)−0.0117 (6)
O40.1002 (11)0.0475 (7)0.0424 (6)−0.0102 (7)−0.0047 (6)−0.0019 (5)
O50.0647 (8)0.0582 (7)0.0345 (6)−0.0042 (6)0.0086 (5)−0.0083 (5)
C10.0401 (9)0.0549 (9)0.0371 (8)−0.0024 (7)−0.0052 (6)−0.0016 (7)
C20.0390 (8)0.0527 (9)0.0379 (8)0.0009 (7)0.0006 (6)0.0009 (7)
C30.0375 (8)0.0340 (7)0.0298 (7)0.0035 (6)0.0027 (6)0.0018 (5)
C40.0420 (9)0.0400 (7)0.0276 (6)0.0000 (6)−0.0010 (6)−0.0025 (5)
C50.0387 (8)0.0436 (8)0.0368 (8)−0.0002 (6)−0.0041 (6)0.0017 (6)
C60.0391 (8)0.0451 (8)0.0401 (8)0.0053 (7)0.0056 (6)−0.0003 (6)
C70.0455 (9)0.0360 (7)0.0314 (7)0.0038 (6)0.0032 (6)−0.0024 (6)
C80.0399 (8)0.0310 (7)0.0300 (7)0.0009 (6)−0.0003 (6)−0.0001 (5)
C90.0451 (9)0.0360 (7)0.0314 (7)−0.0023 (6)−0.0024 (6)0.0007 (6)
C100.0486 (9)0.0446 (8)0.0345 (8)−0.0049 (7)−0.0046 (6)−0.0055 (6)
C110.0346 (8)0.0464 (8)0.0327 (7)0.0005 (6)−0.0059 (6)−0.0049 (6)
C120.0679 (12)0.0845 (14)0.0394 (9)−0.0071 (10)0.0132 (8)0.0016 (9)
Geometric parameters (Å, º) top
O1—C21.2165 (18)C4—H4A0.9300
O2—C21.3617 (18)C5—C61.395 (2)
O2—C31.3764 (17)C6—C71.367 (2)
O3—C51.3515 (18)C6—H6A0.9300
O3—H30.96 (2)C7—C81.399 (2)
O4—C111.1944 (19)C7—H7A0.9300
O5—C111.3183 (17)C8—C91.438 (2)
O5—C121.454 (2)C9—C101.5064 (19)
C1—C91.345 (2)C10—C111.505 (2)
C1—C21.437 (2)C10—H10A0.9700
C1—H1A0.9300C10—H10B0.9700
C3—C41.381 (2)C12—H12A0.9600
C3—C81.3971 (19)C12—H12B0.9600
C4—C51.380 (2)C12—H12C0.9600
C2—O2—C3121.67 (11)C8—C7—H7A119.4
C5—O3—H3111.6 (14)C3—C8—C7116.67 (12)
C11—O5—C12116.88 (13)C3—C8—C9118.30 (13)
C9—C1—C2122.00 (13)C7—C8—C9125.03 (12)
C9—C1—H1A119.0C1—C9—C8119.25 (13)
C2—C1—H1A119.0C1—C9—C10120.65 (13)
O1—C2—O2116.43 (13)C8—C9—C10120.09 (13)
O1—C2—C1125.70 (14)C11—C10—C9114.04 (12)
O2—C2—C1117.87 (13)C11—C10—H10A108.7
O2—C3—C4115.91 (12)C9—C10—H10A108.7
O2—C3—C8120.90 (12)C11—C10—H10B108.7
C4—C3—C8123.19 (13)C9—C10—H10B108.7
C5—C4—C3118.19 (13)H10A—C10—H10B107.6
C5—C4—H4A120.9O4—C11—O5124.29 (14)
C3—C4—H4A120.9O4—C11—C10125.51 (13)
O3—C5—C4122.97 (13)O5—C11—C10110.16 (13)
O3—C5—C6116.74 (14)O5—C12—H12A109.5
C4—C5—C6120.28 (13)O5—C12—H12B109.5
C7—C6—C5120.38 (14)H12A—C12—H12B109.5
C7—C6—H6A119.8O5—C12—H12C109.5
C5—C6—H6A119.8H12A—C12—H12C109.5
C6—C7—C8121.25 (13)H12B—C12—H12C109.5
C6—C7—H7A119.4
C3—O2—C2—O1179.92 (13)C4—C3—C8—C9−178.69 (13)
C3—O2—C2—C1−0.1 (2)C6—C7—C8—C3−1.5 (2)
C9—C1—C2—O1−179.37 (16)C6—C7—C8—C9178.62 (13)
C9—C1—C2—O20.7 (2)C2—C1—C9—C8−0.4 (2)
C2—O2—C3—C4178.95 (12)C2—C1—C9—C10178.94 (14)
C2—O2—C3—C8−0.7 (2)C3—C8—C9—C1−0.4 (2)
O2—C3—C4—C5−179.42 (12)C7—C8—C9—C1179.48 (14)
C8—C3—C4—C50.2 (2)C3—C8—C9—C10−179.72 (13)
C3—C4—C5—O3177.69 (14)C7—C8—C9—C100.1 (2)
C3—C4—C5—C6−1.8 (2)C1—C9—C10—C11108.63 (16)
O3—C5—C6—C7−177.79 (14)C8—C9—C10—C11−72.02 (18)
C4—C5—C6—C71.8 (2)C12—O5—C11—O42.1 (2)
C5—C6—C7—C80.0 (2)C12—O5—C11—C10−179.98 (14)
O2—C3—C8—C7−178.95 (12)C9—C10—C11—O4−8.4 (2)
C4—C3—C8—C71.5 (2)C9—C10—C11—O5173.79 (13)
O2—C3—C8—C90.91 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O1i0.96 (2)1.74 (2)2.7002 (17)177 (2)
C7—H7A···O4ii0.932.473.3320 (18)155
Symmetry codes: (i) x+1/2, −y+1/2, −z+1; (ii) −x+3/2, y−1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O1i0.96 (2)1.74 (2)2.7002 (17)177 (2)
C7—H7A···O4ii0.932.473.3320 (18)155
Symmetry codes: (i) x+1/2, −y+1/2, −z+1; (ii) −x+3/2, y−1/2, z.
 

Acknowledgements

The authors acknowledge the financial support of the Higher Education Commission of Pakistan (HEC) through research projects Nos. 20-2073 and 20-2216 under the National Research Program for Universities.

References

First citationAbd Elhafez, O. M., El Khrisy, E. E. D. A. M., Badria, F. & Fathy, A. E. D. M. (2003). Arch. Pharm. Res. 26, 686–696.  PubMed CAS Google Scholar
 First citationAhmad, H. B., Malana, M. A., Rama, N. H., Ilyas, S., Yousuf, M. & Khan, K. M. (2008). J. Chem. Soc. Pakistan, 30, 834–844.  Google Scholar
 First citationBasanagouda, M., Kulkarni, M. V., Sharma, D., Gupta, V. K., Pranesha, Sandhyarani, P. & Rasal, V. P. (2009). J. Chem. Sci. 121, 485–495.  CSD CrossRef CAS Google Scholar
 First citationBruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationEmmanuel-Giota, A. A., Fylaktakidou, K. C., Litinas, K. E., Nicolaides, D. N. & Hadjipavlou-Litina, D. J. (2001). J. Heterocycl. Chem. 38, 717–722.  CAS Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSubramanian, K., Sivakumar, K., Natarajan, S. & Parthasarathy, S. (1990). Acta Cryst. C46, 1661–1663.  CSD CrossRef CAS IUCr Journals Google Scholar
 First citationUkhov, S. V., Kon'shin, M. E. & Odegova, T. F. (2001). Pharm. Chem. J. 35, 364–365.  CrossRef CAS Google Scholar
 First citationVukovic, N., Sukdolak, S., Solujic, S. & Niciforovic, N. (2010). Arch. Pharm. Res. 33, 5–15.  Web of Science CrossRef CAS PubMed Google Scholar

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 71| Part 9| September 2015| Pages o677-o678
https://doi.org/10.1107/S2056989015014061
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