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Acta Crystallogr Sect E Struct Rep Online. 2010 October 1; 66(Pt 10): o2574.
Published online 2010 September 18. doi:  10.1107/S1600536810036585
PMCID: PMC2983326

4-[(2-Hy­droxy­benzyl­idene)amino]-N-(5-methyl­isoxazol-3-yl)benzene­sulfonamide: a monoclinic polymorph

Abstract

The title compound, C17H15N3O4S, is a monoclinic polymorph with space group P21/c of the previously reported triclinic form in P An external file that holds a picture, illustration, etc.
Object name is e-66-o2574-efi2.jpg [Subashini et al. (2009 [triangle]). J. Chem. Crystallogr. 39, 112–116]. In both polymorphs, intra­molecular O—H(...)N hydrogen bonds and dimer formation via a pair of inter­molecular N—H(...)N hydrogen bonds with an R 2 2(8) motif are observed. The two polymorphs differ in the next level of supra­molecular organization involving C—H(...)O hydrogen bonds with varied packing and different conformations.

Related literature

For the biological relevance of sulfonamide drugs and their Schiff base derivatives, see: Genc et al. (2008 [triangle]); Supuran et al. (1997 [triangle]). For the triclinic polymorph of the title compound, see: Subashini et al. (2009 [triangle]). For An external file that holds a picture, illustration, etc.
Object name is e-66-o2574-efi1.jpg(8) ring motifs in sulfonamides, see: Adsmond & Grant (2001 [triangle]). For conformational studies on sulfonamides, see: Kálmán et al. (1981 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2574-scheme1.jpg

Experimental

Crystal data

  • C17H15N3O4S
  • M r = 357.39
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2574-efi4.jpg
  • a = 7.0374 (1) Å
  • b = 17.9244 (3) Å
  • c = 14.5175 (3) Å
  • β = 112.962 (1)°
  • V = 1686.15 (5) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.22 mm−1
  • T = 293 K
  • 0.25 × 0.22 × 0.20 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2008 [triangle]) T min = 0.947, T max = 0.957
  • 14935 measured reflections
  • 2953 independent reflections
  • 2198 reflections with I > 2σ(I)
  • R int = 0.038

Refinement

  • R[F 2 > 2σ(F 2)] = 0.049
  • wR(F 2) = 0.115
  • S = 1.06
  • 2953 reflections
  • 227 parameters
  • H-atom parameters constrained
  • Δρmax = 0.25 e Å−3
  • Δρmin = −0.30 e Å−3

Data collection: APEX2 (Bruker, 2008 [triangle]); cell refinement: SAINT (Bruker, 2008 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS86 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810036585/is2595sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810036585/is2595Isup2.hkl

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

Acknowledgments

The authors thank the DST-India (FIST programme) for the use of diffractometer at the School of Chemistry, Bharathidasan University.

supplementary crystallographic information

Comment

Sulfonamide drugs are known to have antibacterial, antifungal,antimalarial and antileprotic properties (Genc et al., 2008). Schiff bases derived from sulfonamide compounds also display enzymatic inhibition (Supuran et al., 1997). A polymorph, I, of the title compound has been reported earlier from our group (Subashini et al., 2009). In the present study we report a new dimorph, II, and its crystal structure.

The new dimorph crystallizes in monoclinic system (P21/c) which contains only one molecule in the asymmetric unit (Fig. 1). There is one N—H···N intermolecular hydrogen bond [N2···N3 = 2.899 (3) Å; Table 1], where the amido nitrogen acts as a donor and the nitrogen of the isoxazole acts as an acceptor. The donor and acceptor of one of the Schiff base molecule pair up with another inversely related molecule to form a dimer with graph set notation R22(8) (Fig 2). A similar type of homosynthon is also formed in the polymorph I. A recent statistical survey has shown that the absence of amino group in the sulfonamide compounds further encourages amido protons to hydrogen bond with an activated nitrogen (atom of a heterocycle that lies in conjugation with the amido nitrogen) of the heterocyclic ring to form an optimum sized R22(8) ring motif (Adsmond & Grant, 2001). This could be the reason why both the polymorphs form the same synthons thereby succumb to similar first order arrangement of molecules.

Polymorph II forms an intramolecular C—H···O bond with a graph set notation S(6) similar to its predecessor. It is only the weaker bonds in both the polymorphs that are significantly responsible for the differences in arrangement of molecules in the crystal. In both the polymorphs the homosynthon combines with each other through a couple of weak C—H···O bonds (C10—H10···O1 in polymorph II) forming a large ring motif with graph set notation R44(12) and R44(14) for polymorphs I and II respectively. These homosynthons stretch along a particular direction linked through weak C—H···O interaction forming a supramolecular chain (Fig. 3).

In addition to the packing differences there are changes in the conformations of the molecules which are obvious from their torsion angles. Though there are many possible conformations in which the molecule could exist, the steric and electrostatic constraints of sulfonamides have restricted them to torsion angles between 70–120° and 60–90° for ε1 and ε2 respectively [where ε1 and ε2 are the modulus of the torsion angles along C—S and S—N bonds respectively] (Kálmán et al., 1981). The angles ε1 and ε2 for polymorph II lie in the expected range. The bond lengths and the bond angles among the polymorphs are more or less close to one another but differ hugely in their torsion angles.

To conclude with, both dimorphs posses same intermolecular hydrogen bonds leading to formation of dimers through N—H···N hydrogen bonds, showing similar first level of organization. They differ only in the higher level supramolecular organization through C—H···O hydrogen bonds. A thorough inspection reveals that conformational changes in the molecule lead to the packing differences between the dimorphs.

Experimental

The base of the title compound was synthesized by refluxing ethanolic solutions of 4-amino-N-(5-methyl-3-isoxazolyl) benzene sulfonamide (SMZ) (25 mg, Qualigens) with 2-hydroxy benzaldehyde (SA) (25 mg, LOBA Chemie) in an equimolar ratio. The mixture was refluxed for up to 6 h and then transferred to a beaker which was eventually allowed to evaporate slowly in the mother liquor. After a couple of days yellow crystals separated out. This base was characterized using single-crystal XRD method and found to be a new polymorph.

Refinement

All hydrogen atoms were positioned geometrically and were refined using riding model. The C—H, N—H and O—H bond lengths are 0.93–0.97, 0.86 and 0.82 Å, respectively. [Uiso(H) = 1.2Ueq(aromatic C and N) and 1.5Ueq(methyl C and O)].

Figures

Fig. 1.
An ORTEP view of new dimorph showing 50% probability displacement ellipsoids.
Fig. 2.
Two inversely related molecules form dimer through R22(8) motif. [Symmetry code: (i) -x + 2, -y + 1, -z + 2.]
Fig. 3.
View of supramolecular chain formed through the dimers via weak C—H···O interactions.

Crystal data

C17H15N3O4SF(000) = 744
Mr = 357.39Dx = 1.408 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2953 reflections
a = 7.0374 (1) Åθ = 1.9–25.0°
b = 17.9244 (3) ŵ = 0.22 mm1
c = 14.5175 (3) ÅT = 293 K
β = 112.962 (1)°PRISM, yellow
V = 1686.15 (5) Å30.25 × 0.22 × 0.20 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer2953 independent reflections
Radiation source: fine-focus sealed tube2198 reflections with I > 2σ(I)
graphiteRint = 0.038
[var phi] and ω scansθmax = 25.0°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2008)h = −7→8
Tmin = 0.947, Tmax = 0.957k = −19→21
14935 measured reflectionsl = −17→17

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H-atom parameters constrained
S = 1.06w = 1/[σ2(Fo2) + (0.040P)2 + 0.9817P] where P = (Fo2 + 2Fc2)/3
2953 reflections(Δ/σ)max < 0.001
227 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = −0.30 e Å3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles
Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
S10.61583 (11)0.37355 (3)0.87561 (5)0.0507 (3)
O10.8540 (3)0.47399 (10)0.37502 (16)0.0676 (8)
O20.3998 (3)0.38398 (10)0.84707 (15)0.0625 (7)
O30.7159 (3)0.30911 (10)0.93038 (15)0.0667 (8)
O40.7150 (3)0.63662 (10)0.93497 (15)0.0658 (7)
N10.8210 (4)0.39344 (12)0.51746 (17)0.0551 (8)
N20.7352 (3)0.44313 (11)0.94686 (16)0.0501 (8)
N30.8188 (4)0.56808 (12)0.96244 (18)0.0594 (9)
C10.9847 (4)0.42129 (14)0.3684 (2)0.0528 (10)
C21.0800 (5)0.43213 (17)0.3024 (2)0.0664 (11)
C31.2136 (6)0.38013 (19)0.2939 (3)0.0770 (14)
C41.2539 (6)0.31558 (19)0.3500 (3)0.0787 (16)
C51.1614 (5)0.30449 (15)0.4157 (2)0.0650 (11)
C61.0262 (4)0.35658 (13)0.4270 (2)0.0495 (9)
C70.9426 (4)0.34594 (15)0.5023 (2)0.0549 (10)
C80.7705 (4)0.38551 (14)0.6022 (2)0.0506 (9)
C90.5773 (4)0.40732 (14)0.5957 (2)0.0544 (10)
C100.5264 (4)0.40347 (14)0.6783 (2)0.0511 (10)
C110.6728 (4)0.37909 (13)0.7690 (2)0.0459 (8)
C120.8681 (4)0.35926 (15)0.7762 (2)0.0544 (10)
C130.9170 (4)0.36252 (15)0.6943 (2)0.0561 (10)
C140.6769 (4)0.51741 (13)0.92693 (19)0.0447 (9)
C150.4810 (4)0.54900 (15)0.8754 (2)0.0543 (10)
C160.5134 (4)0.62267 (15)0.8831 (2)0.0551 (10)
C170.3782 (5)0.68894 (17)0.8475 (3)0.0798 (13)
H10.813300.462500.418900.1010*
H21.052900.475100.263600.0800*
H2A0.841300.433201.000300.0600*
H31.278200.388300.249800.0920*
H41.343400.279900.343000.0940*
H51.189600.261100.453800.0780*
H70.978000.303100.541400.0660*
H90.480800.424800.535200.0650*
H100.395100.417100.673300.0610*
H120.966400.343600.837300.0650*
H131.048900.349400.699900.0670*
H150.356500.524200.843100.0650*
H17A0.397300.710400.791100.1200*
H17B0.413200.725100.900300.1200*
H17C0.236700.674200.828100.1200*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0458 (4)0.0386 (4)0.0611 (5)−0.0045 (3)0.0136 (3)0.0006 (3)
O10.0703 (14)0.0556 (12)0.0757 (14)0.0180 (10)0.0273 (12)0.0130 (10)
O20.0397 (11)0.0645 (12)0.0791 (14)−0.0079 (9)0.0186 (10)−0.0030 (10)
O30.0735 (14)0.0420 (10)0.0787 (15)0.0032 (10)0.0233 (12)0.0149 (10)
O40.0604 (13)0.0418 (10)0.0777 (14)0.0020 (9)0.0081 (11)−0.0114 (10)
N10.0494 (14)0.0503 (13)0.0569 (15)−0.0036 (11)0.0112 (12)−0.0023 (11)
N20.0453 (13)0.0437 (12)0.0482 (14)0.0015 (10)0.0040 (10)0.0004 (10)
N30.0514 (15)0.0416 (13)0.0701 (17)0.0036 (11)0.0072 (12)−0.0079 (11)
C10.0501 (17)0.0427 (15)0.0569 (18)−0.0005 (13)0.0115 (14)−0.0037 (13)
C20.075 (2)0.0521 (18)0.072 (2)−0.0019 (16)0.0286 (18)0.0057 (15)
C30.093 (3)0.070 (2)0.081 (2)0.0014 (19)0.048 (2)−0.0028 (18)
C40.086 (3)0.063 (2)0.092 (3)0.0162 (18)0.040 (2)−0.0062 (19)
C50.074 (2)0.0438 (16)0.066 (2)0.0054 (15)0.0150 (17)−0.0016 (14)
C60.0493 (16)0.0375 (14)0.0508 (17)−0.0035 (12)0.0077 (13)−0.0032 (12)
C70.0539 (18)0.0430 (15)0.0542 (18)−0.0101 (13)0.0062 (14)−0.0002 (13)
C80.0494 (17)0.0421 (14)0.0530 (18)−0.0076 (12)0.0120 (14)−0.0018 (13)
C90.0432 (17)0.0520 (16)0.0547 (18)0.0016 (13)0.0048 (14)0.0039 (13)
C100.0371 (15)0.0427 (15)0.066 (2)0.0016 (12)0.0121 (14)0.0005 (13)
C110.0417 (15)0.0334 (13)0.0529 (16)−0.0021 (11)0.0080 (13)−0.0019 (12)
C120.0446 (17)0.0538 (16)0.0513 (18)0.0040 (13)0.0042 (14)0.0002 (13)
C130.0401 (16)0.0588 (18)0.061 (2)0.0018 (13)0.0105 (14)−0.0047 (14)
C140.0452 (16)0.0420 (14)0.0426 (16)0.0005 (12)0.0125 (13)−0.0054 (12)
C150.0433 (16)0.0483 (16)0.0607 (19)0.0027 (12)0.0087 (14)−0.0045 (13)
C160.0545 (18)0.0513 (17)0.0512 (17)0.0068 (14)0.0115 (14)−0.0074 (13)
C170.078 (2)0.0523 (18)0.090 (3)0.0170 (16)0.012 (2)−0.0013 (17)

Geometric parameters (Å, °)

S1—O21.424 (2)C8—C91.382 (4)
S1—O31.423 (2)C9—C101.381 (4)
S1—N21.629 (2)C10—C111.388 (4)
S1—C111.747 (3)C11—C121.384 (4)
O1—C11.348 (3)C12—C131.362 (4)
O4—N31.405 (3)C14—C151.406 (4)
O4—C161.345 (4)C15—C161.337 (4)
O1—H10.8200C16—C171.483 (4)
N1—C71.286 (4)C2—H20.9300
N1—C81.415 (4)C3—H30.9300
N2—C141.390 (3)C4—H40.9300
N3—C141.299 (4)C5—H50.9300
N2—H2A0.8600C7—H70.9300
C1—C21.381 (4)C9—H90.9300
C1—C61.400 (4)C10—H100.9300
C2—C31.363 (5)C12—H120.9300
C3—C41.379 (5)C13—H130.9300
C4—C51.363 (5)C15—H150.9300
C5—C61.388 (4)C17—H17A0.9600
C6—C71.442 (4)C17—H17B0.9600
C8—C131.395 (4)C17—H17C0.9600
S1···H153.1900C2···H15ii3.0700
O1···N12.606 (3)C5···H12ix3.0000
O1···N1i3.245 (3)C7···H132.6700
O1···C10ii3.313 (3)C7···H12.4100
O2···C13iii3.276 (4)C13···H72.6400
O2···C153.010 (3)C13···H2i2.9600
O3···C7iv3.172 (3)C16···H3i2.8500
O1···H10ii2.5300H1···N11.8800
O2···H102.5800H1···C72.4100
O2···H152.5300H2···C13i2.9600
O2···H13iii2.6300H2A···N3vii2.2400
O3···H122.6800H3···O4i2.7400
O3···H4v2.9000H3···C16i2.8500
O3···H7iv2.7800H4···O3x2.9000
O4···H5vi2.6800H5···H72.4200
O4···H3i2.7400H5···O4xi2.6800
N1···O12.606 (3)H7···C132.6400
N1···O1i3.245 (3)H7···H52.4200
N2···N3vii2.898 (4)H7···H132.3100
N3···N2vii2.898 (4)H7···O3ix2.7800
N1···H11.8800H10···O22.5800
N3···H2Avii2.2400H10···O1ii2.5300
C2···C8i3.546 (4)H12···O32.6800
C5···C9viii3.581 (4)H12···C5iv3.0000
C7···O3ix3.172 (3)H13···O2viii2.6300
C8···C2i3.546 (4)H13···C72.6700
C9···C5iii3.581 (4)H13···H72.3100
C10···O1ii3.313 (3)H15···S13.1900
C13···O2viii3.276 (4)H15···O22.5300
C15···O23.010 (3)H15···C2ii3.0700
C2···H17Cii2.9800H17C···C2ii2.9800
O2—S1—O3120.58 (13)N3—C14—C15111.9 (2)
O2—S1—N2108.18 (12)N2—C14—N3117.9 (3)
O2—S1—C11108.84 (13)N2—C14—C15130.2 (2)
O3—S1—N2104.27 (12)C14—C15—C16104.7 (2)
O3—S1—C11107.86 (13)O4—C16—C15109.8 (2)
N2—S1—C11106.23 (12)O4—C16—C17116.1 (2)
N3—O4—C16108.3 (2)C15—C16—C17134.1 (3)
C1—O1—H1110.00C1—C2—H2120.00
C7—N1—C8119.5 (2)C3—C2—H2120.00
S1—N2—C14124.33 (18)C2—C3—H3120.00
O4—N3—C14105.4 (2)C4—C3—H3120.00
S1—N2—H2A118.00C3—C4—H4120.00
C14—N2—H2A118.00C5—C4—H4120.00
C2—C1—C6119.7 (3)C4—C5—H5119.00
O1—C1—C6121.6 (3)C6—C5—H5119.00
O1—C1—C2118.7 (2)N1—C7—H7119.00
C1—C2—C3120.4 (3)C6—C7—H7119.00
C2—C3—C4120.7 (4)C8—C9—H9120.00
C3—C4—C5119.4 (4)C10—C9—H9120.00
C4—C5—C6121.4 (3)C9—C10—H10120.00
C5—C6—C7120.1 (2)C11—C10—H10120.00
C1—C6—C5118.4 (3)C11—C12—H12120.00
C1—C6—C7121.3 (2)C13—C12—H12120.00
N1—C7—C6122.5 (2)C8—C13—H13120.00
N1—C8—C9119.1 (2)C12—C13—H13120.00
N1—C8—C13121.4 (3)C14—C15—H15128.00
C9—C8—C13119.3 (3)C16—C15—H15128.00
C8—C9—C10120.5 (3)C16—C17—H17A109.00
C9—C10—C11119.4 (3)C16—C17—H17B109.00
S1—C11—C12118.9 (2)C16—C17—H17C109.00
S1—C11—C10121.1 (2)H17A—C17—H17B109.00
C10—C11—C12120.0 (3)H17A—C17—H17C110.00
C11—C12—C13120.3 (3)H17B—C17—H17C109.00
C8—C13—C12120.4 (3)
O2—S1—N2—C14−44.7 (3)C2—C1—C6—C5−0.8 (4)
O3—S1—N2—C14−174.2 (2)C2—C1—C6—C7175.1 (3)
C11—S1—N2—C1472.0 (3)C1—C2—C3—C40.8 (5)
O2—S1—C11—C1010.4 (2)C2—C3—C4—C5−1.1 (6)
O2—S1—C11—C12−170.1 (2)C3—C4—C5—C60.4 (5)
O3—S1—C11—C10142.8 (2)C4—C5—C6—C10.5 (5)
O3—S1—C11—C12−37.7 (2)C4—C5—C6—C7−175.4 (3)
N2—S1—C11—C10−105.9 (2)C1—C6—C7—N12.4 (4)
N2—S1—C11—C1273.6 (2)C5—C6—C7—N1178.2 (3)
C16—O4—N3—C14−0.4 (3)N1—C8—C9—C10−177.1 (2)
N3—O4—C16—C15−0.1 (3)C13—C8—C9—C10−2.7 (4)
N3—O4—C16—C17−180.0 (3)N1—C8—C13—C12176.3 (2)
C8—N1—C7—C6−170.2 (3)C9—C8—C13—C122.1 (4)
C7—N1—C8—C9−147.2 (3)C8—C9—C10—C111.5 (4)
C7—N1—C8—C1338.6 (4)C9—C10—C11—S1179.81 (19)
S1—N2—C14—N3−152.9 (2)C9—C10—C11—C120.3 (4)
S1—N2—C14—C1529.5 (4)S1—C11—C12—C13179.6 (2)
O4—N3—C14—N2−177.3 (2)C10—C11—C12—C13−0.9 (4)
O4—N3—C14—C150.7 (3)C11—C12—C13—C8−0.3 (4)
O1—C1—C2—C3179.8 (3)N2—C14—C15—C16177.0 (3)
C6—C1—C2—C30.2 (5)N3—C14—C15—C16−0.7 (3)
O1—C1—C6—C5179.6 (3)C14—C15—C16—O40.4 (3)
O1—C1—C6—C7−4.6 (4)C14—C15—C16—C17−179.7 (3)

Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x−1, y, z; (iv) x, −y+1/2, z+1/2; (v) x−1, −y+1/2, z+1/2; (vi) −x+2, y+1/2, −z+3/2; (vii) −x+2, −y+1, −z+2; (viii) x+1, y, z; (ix) x, −y+1/2, z−1/2; (x) x+1, −y+1/2, z−1/2; (xi) −x+2, y−1/2, −z+3/2.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1···N10.821.882.606 (3)147
N2—H2A···N3vii0.862.242.898 (4)134
C10—H10···O1ii0.932.533.313 (3)141
C15—H15···O20.932.533.010 (3)112

Symmetry codes: (vii) −x+2, −y+1, −z+2; (ii) −x+1, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS2595).

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