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Acta Crystallogr Sect E Struct Rep Online. 2010 March 1; 66(Pt 3): o658–o659.
Published online 2010 February 20. doi:  10.1107/S1600536810006124
PMCID: PMC2983612

1-[5-Acetyl-4-(4-bromo­phen­yl)-2,6-dimethyl-1,4-dihydro­pyridin-3-yl]ethanone monohydrate

Abstract

The 1,4-dihydro­pyridine ring in the title hydrate, C17H18BrNO2·H2O, has a flattened-boat conformation, and the benzene ring is occupies a position orthogonal to this [dihedral angle: 82.19 (16)°]. In the crystal packing, supra­molecular arrays mediated by N—H(...)Owater and Owater—H(...)Ocarbon­yl hydrogen bonding are formed in the bc plane. A highly disordered solvent mol­ecule is present within a mol­ecular cavity defined by the organic and water mol­ecules. Its contribution to the electron density was removed from the observed data in the final cycles of refinement and the formula, mol­ecular weight and density are given without taking into account the contribution of the solvent mol­ecule.

Related literature

For background to the pharmacological potential of Hantzsch 4-dihydro­pyridines, see: Gaudio et al. (1994 [triangle]); Böcker & Guengerich (1986 [triangle]); Gordeev et al. (1996 [triangle]); Sunkel et al. (1992 [triangle]); Vo et al. (1995 [triangle]); Cooper et al. (1992 [triangle]). For the synthesis, see: Rathore et al. (2009 [triangle]). For a related structure, see: de Armas et al. (2000 [triangle]). For additional geometric analysis, see: Cremer & Pople, (1975 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o658-scheme1.jpg

Experimental

Crystal data

  • C17H18BrNO2·H2O
  • M r = 366.25
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o658-efi1.jpg
  • a = 13.5236 (3) Å
  • b = 10.3866 (2) Å
  • c = 15.0939 (3) Å
  • β = 102.112 (1)°
  • V = 2072.96 (7) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 1.99 mm−1
  • T = 293 K
  • 0.21 × 0.11 × 0.10 mm

Data collection

  • Bruker SMART APEX CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 1998 [triangle]) T min = 0.768, T max = 0.819
  • 27847 measured reflections
  • 3658 independent reflections
  • 2611 reflections with I > 2σ(I)
  • R int = 0.032

Refinement

  • R[F 2 > 2σ(F 2)] = 0.049
  • wR(F 2) = 0.147
  • S = 1.08
  • 3658 reflections
  • 212 parameters
  • 4 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.56 e Å−3
  • Δρmin = −0.75 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, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]) and PLATON (Spek, 2009 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and DIAMOND (Brandenburg, 2006 [triangle]); software used to prepare material for publication: publCIF (Westrip, 2010 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks general, I. DOI: 10.1107/S1600536810006124/hg2647sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810006124/hg2647Isup2.hkl

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

Acknowledgments

VV is grateful to the DST-India for funding through the Young Scientist Scheme (Fast Track Proposal).

supplementary crystallographic information

Comment

Biologically active compounds based on Hantzsch 1,4-dihydropyridines (DHPs) have been demonstrated to possess a range of pharmaceutical properties, such as vasodilator, antihypertensive, bronchodilator, heptaprotective, anti-tumour, anti-mutagenic, geroprotective and anti-diabetic agents (Gaudio et al., 1994). For example, calcium channel blockers Nifedipine, Nitrendipine and Nimodipine have found commercial utility (Böcker & Guengerich, 1986; Gordeev et al., 1996). Various DHP-based calcium antagonists have been introduced for the treatment of congestive heart failure (Sunkel et al., 1992; Vo et al., 1995). Finally, a number of DHPs having anti-aggregatory activity of platelet are known (Cooper et al., 1992). In continuation of study investigating crystal packing motifs of these compounds (Rathore et al. (2009), the title hydrate, (I), was investigated.

The molecular structures of the components of (I) are shown in Fig. 1. The 1,4-dihydropyridine ring in (I) has a flattened-boat conformation with the N1 and C3 atoms lying above the plane defined by the C1,C2,C4 and C5 atoms. This assignments is quantified by the ring puckering parameters (Cremer & Pople, 1975): Q = 0.312 (3) Å, θ = 72.0 (6) °, and [var phi]2 = 175.4 (5) °. The aryl ring is orthogonal to the 1,4-dihydropyridine ring with a dihedral angle between their respective least-squares planes of 82.19 (16) °. The observed conformation in (I) is entirely consistent with those found for the two closely related aryl derivatives of (I), i.e. with PhNO2-3 (Rathore et al., (2009) and with PhOH-4, as the monohydrate (de Armas et al., 2000). The difference between the structures relate to the relative disposition of the acetyl groups. In each case, these are essentially co-planar with the 1,4-dihydropyridine ring and in the PhNO2-3 derivative (Rathore et al., (2009), both carbonyl atoms are orientated away from the amine group whereas in (I) and in PhOH-4 monohydrate (de Armas et al., 2000), one is orientated towards the amine group.

The crystal packing features N–H···Owater and OwaterH···Ocarbonyl hydrogen bonding, Table 1. These link the molecules into a layer in the bc plane, Fig. 2, with all the aryl rings being orientated to one side of the plane for each layer. Pairs of layers interdigitate to form sandwich structure, Fig. 3.

Experimental

3,5-Diacetyl-2,6-dimethyl-1,4-dihydro-4-(4-bromophenyl)-pyridine was prepared according to Hantzsch pyridine synthesis (Rathore et al., 2009). 4-Bromobenzaldehyde (10 mmol), acetylacetone (20 mmol) and ammonium acetate (10 mmol) were taken in a 1:2:1 mole ratio along with ethanol (20 ml) as solvent in a RB-flask and refluxed over a steam-bath until the colour of the solution changed to red-orange (approximately 2 h). The solution was kept under ice-cold conditions in order to precipitate the solid product. This was extracted using diethyl ether and then excess solvent was distilled off. The purity of the crude product was checked through TLC and recrystallized using mixture of acetone and diethyl ether (3:1); Yield: 85%; m.pt. 382 K. Crystals were grown from an acetone and ether (3:1) solution over three days. IR (KBr): ν(N—H) 3358, ν(Ar—H) 3062, ν(C═O) 1678, ν(C–Br) 744 cm-1.

Refinement

The C-bound H atoms were geometrically placed (C–H = 0.93–0.96 Å) and refined as riding with Uiso(H) = 1.2–1.5Ueq(C). The remaining H were located from a difference map and refined with O–H = 0.840±0.001 (with H1w···H2w = 1.39±0.01) and N–H = 0.880±0.001, and with Uiso(H) = nUeq(parent atom), with n = 1.5 for O and n = 1.2 for N. Unresolved disordered solvent was evident in the final cycles of the refinement. This was modelled with the SQUEEZE option in PLATON (Spek, 2009); the solvent cavity had volume 251 Å3. In the final cycles of refinement, this contribution to the electron density was removed from the observed data. The density, the F(000) value, the molecular weight, and the formula are given without taking into account the contribution of the solvent molecule(s). The structure factor programme detects differences in R values. These discrepancies arise as the structure factor checking program does not take into account the SQUEEZE procedure applied to the data, as explained in the refinement section, and appended at the end of the CIF.

Figures

Fig. 1.
The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 35% probability level.
Fig. 2.
A view of a supramolecular array formed in the bc plane of (I). The N–H···O and O–H···O hydrogen bonds are shown as blue and orange dashed lines, respectively. Colour code: Br, cyan; O, red; ...
Fig. 3.
A view in projection down the c axis highlighting the sandwich-like packing along the a axis in (I). Colour code: Br, cyan; O, red; N, blue; C, grey; and H, green.

Crystal data

C17H18BrNO2·H2OF(000) = 752
Mr = 366.25Dx = 1.174 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7408 reflections
a = 13.5236 (3) Åθ = 2.4–22.7°
b = 10.3866 (2) ŵ = 1.99 mm1
c = 15.0939 (3) ÅT = 293 K
β = 102.112 (1)°Block, colourless
V = 2072.96 (7) Å30.21 × 0.11 × 0.10 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer3658 independent reflections
Radiation source: fine-focus sealed tube2611 reflections with I > 2σ(I)
graphiteRint = 0.032
ω scansθmax = 25.0°, θmin = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 1998)h = −16→15
Tmin = 0.768, Tmax = 0.819k = 0→12
27847 measured reflectionsl = 0→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) = 0.147H atoms treated by a mixture of independent and constrained refinement
S = 1.08w = 1/[σ2(Fo2) + (0.071P)2 + 1.0899P] where P = (Fo2 + 2Fc2)/3
3658 reflections(Δ/σ)max = 0.001
212 parametersΔρmax = 0.56 e Å3
4 restraintsΔρmin = −0.75 e Å3

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Br−0.15936 (3)0.08244 (7)0.77808 (4)0.1238 (3)
O10.3468 (2)0.35143 (19)0.87926 (13)0.0640 (6)
O20.3961 (2)−0.2324 (2)0.88848 (14)0.0691 (7)
N10.35579 (19)0.0281 (2)1.09364 (14)0.0423 (5)
H1N0.367 (2)0.001 (3)1.1502 (7)0.051*
C10.3493 (2)0.1585 (2)1.07651 (16)0.0388 (6)
C20.33562 (19)0.1993 (2)0.98949 (16)0.0350 (6)
C30.3071 (2)0.1007 (2)0.91317 (16)0.0356 (6)
H30.33580.13030.86230.043*
C40.3524 (2)−0.0305 (2)0.94161 (16)0.0365 (6)
C50.3691 (2)−0.0629 (2)1.03099 (17)0.0389 (6)
C60.3600 (3)0.2362 (3)1.16203 (18)0.0559 (8)
H6A0.42530.27681.17520.084*
H6B0.35350.18051.21130.084*
H6C0.30820.30081.15420.084*
C70.3489 (2)0.3316 (2)0.96005 (17)0.0425 (6)
C80.3688 (3)0.4445 (3)1.0225 (2)0.0683 (10)
H8A0.37820.52010.98860.102*
H8B0.42870.42891.06810.102*
H8C0.31230.45701.05080.102*
C90.3687 (2)−0.1214 (3)0.87207 (19)0.0463 (7)
C100.3516 (3)−0.0759 (3)0.7756 (2)0.0723 (11)
H10A0.3597−0.14690.73700.108*
H10B0.3997−0.00990.77050.108*
H10C0.2843−0.04200.75770.108*
C110.4025 (3)−0.1911 (3)1.07260 (19)0.0558 (8)
H11A0.3465−0.25001.06120.084*
H11B0.4262−0.18111.13680.084*
H11C0.4561−0.22431.04640.084*
C120.1926 (2)0.0954 (3)0.88046 (17)0.0417 (6)
C130.1332 (2)0.0057 (3)0.9125 (2)0.0638 (9)
H130.1640−0.05420.95530.077*
C140.0291 (3)0.0023 (4)0.8828 (3)0.0778 (11)
H14−0.0092−0.05920.90540.093*
C15−0.0166 (3)0.0895 (4)0.8205 (3)0.0766 (10)
C160.0384 (3)0.1807 (4)0.7877 (3)0.0858 (12)
H160.00630.24060.74560.103*
C170.1432 (3)0.1839 (4)0.8176 (2)0.0686 (9)
H170.18050.24650.79510.082*
O1W0.40559 (17)−0.05147 (18)1.28219 (12)0.0510 (5)
H1w0.392 (3)0.0100 (17)1.3139 (18)0.076*
H2w0.397 (3)−0.1227 (12)1.3060 (19)0.076*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br0.0512 (3)0.1686 (6)0.1423 (5)−0.0066 (3)−0.0009 (3)0.0017 (4)
O10.1159 (19)0.0375 (11)0.0411 (11)−0.0092 (11)0.0222 (11)0.0047 (9)
O20.117 (2)0.0393 (12)0.0529 (12)0.0149 (12)0.0218 (12)−0.0105 (10)
N10.0692 (15)0.0318 (12)0.0288 (11)0.0016 (11)0.0171 (11)0.0033 (9)
C10.0527 (16)0.0324 (14)0.0334 (13)−0.0002 (12)0.0141 (11)−0.0015 (11)
C20.0460 (14)0.0276 (13)0.0329 (13)0.0004 (11)0.0114 (11)−0.0029 (10)
C30.0488 (15)0.0305 (13)0.0289 (12)−0.0032 (11)0.0115 (11)−0.0018 (10)
C40.0500 (15)0.0261 (13)0.0345 (13)−0.0033 (11)0.0112 (11)−0.0032 (10)
C50.0489 (15)0.0315 (14)0.0384 (14)−0.0017 (11)0.0139 (12)−0.0024 (11)
C60.094 (2)0.0406 (16)0.0359 (15)0.0006 (16)0.0212 (15)−0.0059 (12)
C70.0553 (16)0.0337 (14)0.0383 (15)0.0002 (12)0.0095 (12)−0.0004 (11)
C80.119 (3)0.0339 (16)0.0524 (19)−0.0096 (17)0.019 (2)−0.0023 (14)
C90.0599 (18)0.0373 (16)0.0431 (15)−0.0024 (13)0.0142 (13)−0.0079 (12)
C100.128 (4)0.053 (2)0.0389 (17)0.0131 (19)0.026 (2)−0.0095 (14)
C110.089 (2)0.0354 (15)0.0454 (16)0.0085 (15)0.0189 (16)0.0056 (12)
C120.0522 (16)0.0400 (14)0.0342 (13)−0.0012 (13)0.0123 (12)−0.0037 (11)
C130.057 (2)0.064 (2)0.069 (2)−0.0095 (16)0.0116 (16)0.0129 (17)
C140.061 (2)0.088 (3)0.087 (3)−0.019 (2)0.020 (2)0.005 (2)
C150.0472 (19)0.097 (3)0.082 (3)−0.005 (2)0.0069 (18)−0.005 (2)
C160.061 (2)0.093 (3)0.093 (3)0.011 (2)−0.005 (2)0.028 (2)
C170.059 (2)0.076 (2)0.067 (2)−0.0011 (18)0.0042 (16)0.0236 (18)
O1w0.0796 (15)0.0376 (10)0.0379 (11)0.0059 (10)0.0170 (10)0.0048 (8)

Geometric parameters (Å, °)

Br—C151.904 (4)C8—H8B0.9600
O1—C71.231 (3)C8—H8C0.9600
O2—C91.221 (3)C9—C101.501 (4)
N1—C51.375 (3)C10—H10A0.9600
N1—C11.378 (3)C10—H10B0.9600
N1—H1n0.881 (14)C10—H10C0.9600
C1—C21.355 (3)C11—H11A0.9600
C1—C61.503 (4)C11—H11B0.9600
C2—C71.467 (4)C11—H11C0.9600
C2—C31.530 (3)C12—C131.383 (4)
C3—C41.519 (3)C12—C171.388 (4)
C3—C121.523 (4)C13—C141.385 (5)
C3—H30.9800C13—H130.9300
C4—C51.363 (4)C14—C151.358 (6)
C4—C91.462 (4)C14—H140.9300
C5—C111.501 (4)C15—C161.360 (6)
C6—H6A0.9600C16—C171.394 (5)
C6—H6B0.9600C16—H160.9300
C6—H6C0.9600C17—H170.9300
C7—C81.492 (4)O1w—H1w0.84 (2)
C8—H8A0.9600O1w—H2w0.841 (18)
C5—N1—C1124.0 (2)H8B—C8—H8C109.5
C5—N1—H1N115 (2)O2—C9—C4123.3 (3)
C1—N1—H1N119 (2)O2—C9—C10118.2 (2)
C2—C1—N1118.7 (2)C4—C9—C10118.5 (2)
C2—C1—C6129.3 (2)C9—C10—H10A109.5
N1—C1—C6112.0 (2)C9—C10—H10B109.5
C1—C2—C7125.9 (2)H10A—C10—H10B109.5
C1—C2—C3118.8 (2)C9—C10—H10C109.5
C7—C2—C3115.3 (2)H10A—C10—H10C109.5
C4—C3—C12112.4 (2)H10B—C10—H10C109.5
C4—C3—C2111.4 (2)C5—C11—H11A109.5
C12—C3—C2110.3 (2)C5—C11—H11B109.5
C4—C3—H3107.5H11A—C11—H11B109.5
C12—C3—H3107.5C5—C11—H11C109.5
C2—C3—H3107.5H11A—C11—H11C109.5
C5—C4—C9122.2 (2)H11B—C11—H11C109.5
C5—C4—C3118.3 (2)C13—C12—C17116.9 (3)
C9—C4—C3119.3 (2)C13—C12—C3122.5 (3)
C4—C5—N1119.5 (2)C17—C12—C3120.6 (3)
C4—C5—C11127.3 (2)C12—C13—C14122.0 (3)
N1—C5—C11113.2 (2)C12—C13—H13119.0
C1—C6—H6A109.5C14—C13—H13119.0
C1—C6—H6B109.5C15—C14—C13119.4 (3)
H6A—C6—H6B109.5C15—C14—H14120.3
C1—C6—H6C109.5C13—C14—H14120.3
H6A—C6—H6C109.5C14—C15—C16120.8 (3)
H6B—C6—H6C109.5C14—C15—Br119.3 (3)
O1—C7—C2118.6 (2)C16—C15—Br119.9 (3)
O1—C7—C8117.2 (2)C15—C16—C17119.7 (4)
C2—C7—C8124.2 (2)C15—C16—H16120.1
C7—C8—H8A109.5C17—C16—H16120.1
C7—C8—H8B109.5C12—C17—C16121.1 (3)
H8A—C8—H8B109.5C12—C17—H17119.5
C7—C8—H8C109.5C16—C17—H17119.5
H8A—C8—H8C109.5H1w—O1w—H2w111 (3)
C5—N1—C1—C213.2 (4)C3—C2—C7—O1−7.3 (4)
C5—N1—C1—C6−166.2 (3)C1—C2—C7—C8−7.1 (5)
N1—C1—C2—C7−165.8 (3)C3—C2—C7—C8175.0 (3)
C6—C1—C2—C713.5 (5)C5—C4—C9—O21.6 (5)
N1—C1—C2—C312.1 (4)C3—C4—C9—O2−173.2 (3)
C6—C1—C2—C3−168.6 (3)C5—C4—C9—C10−178.1 (3)
C1—C2—C3—C4−31.5 (3)C3—C4—C9—C107.2 (4)
C7—C2—C3—C4146.5 (2)C4—C3—C12—C1329.6 (3)
C1—C2—C3—C1294.1 (3)C2—C3—C12—C13−95.5 (3)
C7—C2—C3—C12−87.9 (3)C4—C3—C12—C17−151.8 (3)
C12—C3—C4—C5−95.4 (3)C2—C3—C12—C1783.1 (3)
C2—C3—C4—C529.0 (3)C17—C12—C13—C140.9 (5)
C12—C3—C4—C979.5 (3)C3—C12—C13—C14179.5 (3)
C2—C3—C4—C9−156.1 (2)C12—C13—C14—C15−0.1 (6)
C9—C4—C5—N1177.7 (3)C13—C14—C15—C16−0.7 (6)
C3—C4—C5—N1−7.5 (4)C13—C14—C15—Br178.7 (3)
C9—C4—C5—C11−1.8 (5)C14—C15—C16—C170.7 (7)
C3—C4—C5—C11173.0 (3)Br—C15—C16—C17−178.7 (3)
C1—N1—C5—C4−15.7 (4)C13—C12—C17—C16−0.8 (5)
C1—N1—C5—C11163.9 (3)C3—C12—C17—C16−179.5 (3)
C1—C2—C7—O1170.6 (3)C15—C16—C17—C120.0 (6)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1n···O1w0.881 (14)2.025 (13)2.904 (3)174 (2)
O1W—H1w···O1i0.84 (2)1.92 (3)2.754 (3)174 (4)
O1W—H2w···O2ii0.84 (2)1.96 (2)2.778 (3)166 (2)

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HG2647).

References

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