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Acta Crystallogr Sect E Struct Rep Online. 2008 December 1; 64(Pt 12): o2492–o2493.
Published online 2008 November 29. doi:  10.1107/S1600536808039810
PMCID: PMC2959903

tert-Butyl 2-(3-acetyl­amino-2-oxo-1,2-dihydro-1-pyrid­yl)acetate

Abstract

The title compound, C13H18N2O4, crystallizes as discrete mol­ecules associated as N—H(...)O hydrogen-bonded dimers disposed about a crystallographic inversion centre. The structure is the first solid-state structure for a 3-acetyl­pyridone without C-4 to C-6 substituents. The amide subsituent at C-3 is coplanar with the pyridone ring, while the tert-butyl ester group is orthogonal to the pyridine ring. The amide and ester carbonyl O atoms are not involved in strong hydrogen bonding with only a number of intramolecular and intermolecular C—H(...)O inter­actions apparent in the structure.

Related literature

For general background, see: Bernstein et al. (1994 [triangle]); Dragovich et al. (2002 [triangle]); Hu et al. (2008 [triangle]); Karis et al. (2007 [triangle]); Kim et al. (2008 [triangle]); Loughlin et al. (2004 [triangle]); Reiner et al. (1999 [triangle]); Semple et al. (1998 [triangle]); Veale et al. (1995 [triangle]). For the synthesis, see: Sanderson et al. (1997 [triangle]); Tamura et al. (1996 [triangle]). For related structures. see: Karis et al. (2006 [triangle]); Yang & Craven (1998 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-o2492-scheme1.jpg

Experimental

Crystal data

  • C13H18N2O4
  • M r = 266.29
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o2492-efi1.jpg
  • a = 13.9417 (15) Å
  • b = 5.585 (1) Å
  • c = 17.861 (2) Å
  • β = 97.039 (9)°
  • V = 1380.3 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 295 (2) K
  • 0.40 × 0.30 × 0.20 mm

Data collection

  • Rigaku AFC-7R diffractometer
  • Absorption correction: none
  • 2731 measured reflections
  • 2428 independent reflections
  • 1482 reflections with I > 2σ(I)
  • R int = 0.046
  • 3 standard reflections every 150 reflections intensity decay: 0.6%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.052
  • wR(F 2) = 0.162
  • S = 1.02
  • 2428 reflections
  • 176 parameters
  • H-atom parameters constrained
  • Δρmax = 0.27 e Å−3
  • Δρmin = −0.27 e Å−3

Data collection: MSC/AFC7 Diffractometer Control Software (Molecular Structure Corporation, 1999 [triangle]); cell refinement: MSC/AFC7 Diffractometer Control Software; data reduction: TEXSAN for Windows (Molecular Structure Corporation, 2001 [triangle]); program(s) used to solve structure: TEXSAN for Windows; program(s) used to refine structure: TEXSAN for Windows and SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: TEXSAN for Windows and PLATON (Spek, 2003 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808039810/bt2816sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808039810/bt2816Isup2.hkl

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

Acknowledgments

We acknowledge financial support of this work by Griffith University, Eskitis Institute for Cell and Molecular Therapies, Griffith University, and Natural Product Discovery, Griffith University. We also thank Alan White for professional support in this work.

supplementary crystallographic information

Comment

Increased binding affinity of pyridone based scaffolds as P4—P2 conformational restraints (Dragovich et al., 2002; Reiner et al., 1999; Semple et al., 1998; Veale et al., 1995; Bernstein et al., 1994) in peptidiomimetics (Loughlin et al., 2004, and references therein) is often associated with the substituent functionality at N1 and C3 of the pyridone ring. This has been reflected by enzyme-ligand crystal structures of a C3-amidoaryl pyridone with human rhinovirus (HRV) 3 C protease (3CP) (Dragovich et al., 2002), and a C3-sulfonylamide pyridone with porcine pancreatic elastase (Bernstein et al., 1994). Similiarly, other enzyme-ligand interactions have been observed in the solid state with kinases; a N1-aryl pyridone with Met kinase (Kim et al., 2008) and a N1-aryl C3-aryl pyridone with KDR kinase (Hu et al., 2008). Thus an understanding of the structure of substituted pyridone compounds is important. Elsewhere, the facile synthesis of N1, C3-substituted pyridones is reported (Karis et al., 2007). Herein we report the first solid state structure (II) for a 3-acetylpyridone without C4 to C6 substituents.

The structure of (II) consists of discrete molecular units (Fig. 1) which form N3—H3···O2 hydrogen bonded dimers disposed about a crystallographic centre of symmetry (Figure 2, Table 1). The amide N3—C31—O3—C32 is co-planar with the pyridone ring with the O3···H4 contact distance 2.23 Å. The tert-butyl ester group attached to N1 lies orthogonal to the pyridone ring with the C2—N1—C11—C12 torsion angle -81.1 (2)°. The geometry of the pyridone ring is in accord with related structures (Yang & Craven, 1998; Karis et al., 2006) with the C2—C3 distance 1.440 (3)Å while the other C—C and C—N distance range from 1.333 (4) - 1.402 (4) Å. The N3—C31 distance of 1.362 (3)Å is shorter than the N3—C3 distance of 1.399 (3) Å; indicating a preference for involvement of N3 in conjugation with the amide rather than the pyridone. The carbonyl groups C31—O3 and C21—O11 are not involved in strong hydrogen bonding interactions with only a number of C—H···O interactions apparent in the crystal lattice (Table 2).

Experimental

Tert-Butyl 2-(3'-amino-2'-oxopyridin-1'(2H)-yl)acetate (compound (I)) was prepared by N-alkylation of nitropyridone with sodium hydride and tert-butyl bromoacetate (Sanderson et al., 1997; Tamura et al., 1996), and subsequent hydrogenation over palladium-on-carbon (Tamura et al., 1996).

For the preparation of compound (II), compound (I) (0.78 g, 3.48 mmol) was dissolved in a mixture of dry dichloromethane (10 ml) and triethylamine (0.97 ml, 6.96 mmol) under nitrogen. Acetyl chloride (0.50 ml, 6.96 mmol) was added dropwise at 295 K. The resulting mixture was stirred for 4 h and then concentrated to give a suspension of the product and triethylamine hydrochloride. The suspension was directly transferred to a silica gel column using dichloromethane with 0.5% triethylamine and eluted with an ethyl acetate /dichloromethane gradient (0 to 20% ethyl acetate, with 0.5% triethyl amine. Red crystals of (II) (m.p. 415–418 K) (0.91 g, 98%) were isolated by slow evaporation from an ethyl acetate /dichloromethane solution. Analysis found: C 58.73, H 6.84, N 10.36%; calculated for C13H18N2O4: C 58.64, H 6.81, N 10.52%. νmax(KBr) cm-1 3318, 2974, 1716, 1646, 1605, 1532, 1512. δH (400 MHz, CDCl3, p.p.m.) 1.49 (9H, s, C(CH3)3), 2.19 (3H, s, CH3), 4.58 (2H, s, H2), 6.27 (1H, dd, J = 7.0, 7.0 Hz, H5'), 6.92 (1H, dd, J = 7.0, 1.6 Hz, H6'), 8.35 (1H, brs, Wh1/2 = 11 Hz, NH), 8.39 (1H, dd, J = 7.2, 1.6 Hz, H4'). δC (100 MHz, CDCl3) 24.7 (CH3), 28.0 (C(CH3)3), 51.6 (C2), 83.1 (C(CH3)3), 106.8 (C5'), 122.4 (C4'), 129.3 (C3'), 130.2 (C6'), 157.4 (C2'), 166.2 (C1), 169.0 (CO). MS (ES+) 289.2 (MNa+, 30%) 273.2 (MLi+, 40%).

Refinement

Carbon bonded H atoms were included in idealized positions and refined as riding atoms, with C—H set to 0.95–0.96 Å. Uiso(H) values were set to 1.2Ueq (aromatic, methylene) and 1.5Ueq (methyl) of the parent atom. The amide proton was located from difference Fourier maps and refined with N—H set to 0.86Å and Uiso(H) values set to 1.2Ueq of the parent atom. Considerable thermal motion was apparent in the peripheral carbons of the tert-butyl group.

Figures

Fig. 1.
View of the molecular structure of (II) with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radii.
Fig. 2.
View of the dimeric structure of (II).
Fig. 3.
The formation of the title compound.

Crystal data

C13H18N2O4F000 = 568
Mr = 266.29Dx = 1.281 Mg m3
Monoclinic, P21/cMo Kα radiation λ = 0.71069 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 13.9417 (15) Åθ = 12.6–17.5º
b = 5.585 (1) ŵ = 0.10 mm1
c = 17.861 (2) ÅT = 295 (2) K
β = 97.039 (9)ºBlock, red
V = 1380.3 (3) Å30.40 × 0.30 × 0.20 mm
Z = 4

Data collection

Rigaku AFC-7R diffractometerRint = 0.046
Radiation source: Rigaku rotating anodeθmax = 25.0º
Monochromator: graphiteθmin = 2.6º
T = 295 Kh = −16→16
ω–2θ scansk = −6→0
Absorption correction: nonel = −21→10
2731 measured reflections3 standard reflections
2428 independent reflections every 150 reflections
1482 reflections with I > 2σ(I) intensity decay: 0.6%

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.052H-atom parameters constrained
wR(F2) = 0.162  w = 1/[σ2(Fo2) + (0.0906P)2 + 0.0473P] where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.001
2428 reflectionsΔρmax = 0.27 e Å3
176 parametersΔρmin = −0.27 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

Special details

Experimental. The scan width was (1.79 + 0.30tanθ)° with an ω scan speed of 16° per minute (up to 4 scans to achieve I/σ(I) > 10). Stationary background counts were recorded at each end of the scan, and the scan time:background time ratio was 2:1.
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
O20.93631 (11)0.2790 (3)0.03272 (10)0.0595 (6)
O31.26910 (13)0.2449 (4)0.15628 (14)0.0940 (9)
O110.79117 (14)0.2673 (4)0.16249 (13)0.0868 (9)
O120.66171 (11)0.0894 (3)0.09995 (9)0.0520 (6)
N10.91347 (13)−0.0488 (3)0.10449 (11)0.0487 (6)
N31.12376 (12)0.3204 (4)0.08928 (11)0.0497 (7)
C20.97001 (15)0.1321 (4)0.08098 (12)0.0450 (7)
C31.06936 (15)0.1361 (4)0.11623 (12)0.0450 (7)
C41.10110 (17)−0.0279 (5)0.16998 (14)0.0546 (8)
C51.0390 (2)−0.2076 (5)0.19027 (15)0.0634 (10)
C60.94768 (18)−0.2158 (5)0.15792 (15)0.0580 (9)
C110.81146 (16)−0.0501 (4)0.07545 (14)0.0508 (8)
C120.75508 (16)0.1222 (4)0.11859 (14)0.0505 (8)
C130.58947 (17)0.2243 (5)0.13832 (15)0.0569 (9)
C140.4945 (2)0.1252 (7)0.1020 (2)0.0982 (15)
C150.6042 (2)0.1659 (8)0.22108 (18)0.0934 (14)
C160.5968 (3)0.4858 (6)0.1224 (3)0.1150 (18)
C311.21909 (17)0.3673 (5)0.11050 (15)0.0577 (9)
C321.25913 (17)0.5768 (6)0.07310 (16)0.0683 (10)
H31.094000.413600.055800.0590*
H41.16570−0.020400.194100.0650*
H51.06240−0.322800.227000.0750*
H60.90590−0.338200.171800.0690*
H14A0.442700.193300.125700.1480*
H14B0.49430−0.045700.107800.1480*
H14C0.486100.164700.049300.1480*
H15A0.663000.238600.244000.1400*
H15B0.60820−0.004600.227600.1400*
H15C0.550800.226400.244600.1400*
H16A0.656000.547500.148400.1730*
H16B0.543000.568100.139400.1730*
H16C0.596100.509900.069100.1730*
H32A1.319900.533700.056700.1030*
H32B1.268600.707400.108200.1030*
H32C1.214700.624200.030300.1030*
H1110.78650−0.207600.079800.0610*
H1120.80430−0.005300.023700.0610*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O20.0418 (9)0.0716 (12)0.0638 (10)−0.0042 (9)0.0008 (8)0.0138 (10)
O30.0447 (10)0.1068 (17)0.1239 (19)−0.0035 (11)−0.0167 (11)0.0397 (15)
O110.0571 (12)0.0988 (16)0.1066 (16)−0.0158 (11)0.0190 (11)−0.0554 (14)
O120.0417 (9)0.0507 (10)0.0646 (10)0.0020 (7)0.0110 (7)−0.0070 (9)
N10.0405 (10)0.0493 (11)0.0577 (12)−0.0012 (9)0.0119 (9)−0.0033 (10)
N30.0332 (10)0.0621 (13)0.0531 (11)0.0032 (9)0.0028 (8)0.0019 (10)
C20.0375 (11)0.0517 (14)0.0468 (12)0.0008 (11)0.0096 (10)−0.0036 (12)
C30.0375 (11)0.0528 (14)0.0461 (12)0.0056 (10)0.0111 (10)−0.0059 (11)
C40.0445 (13)0.0635 (16)0.0555 (14)0.0082 (12)0.0052 (11)−0.0015 (13)
C50.0629 (16)0.0598 (17)0.0673 (17)0.0109 (14)0.0076 (13)0.0107 (14)
C60.0583 (15)0.0487 (15)0.0680 (16)0.0000 (12)0.0118 (13)0.0020 (13)
C110.0404 (12)0.0517 (14)0.0614 (14)−0.0088 (11)0.0112 (11)−0.0087 (12)
C120.0421 (13)0.0530 (14)0.0575 (14)−0.0060 (11)0.0100 (11)−0.0062 (12)
C130.0495 (14)0.0502 (15)0.0751 (17)0.0081 (11)0.0243 (12)0.0020 (13)
C140.0472 (16)0.105 (3)0.142 (3)0.0181 (17)0.0101 (18)−0.018 (2)
C150.083 (2)0.122 (3)0.083 (2)0.014 (2)0.0411 (18)0.010 (2)
C160.127 (3)0.0546 (19)0.180 (4)0.024 (2)0.085 (3)0.024 (2)
C310.0377 (13)0.0680 (17)0.0671 (16)0.0021 (12)0.0049 (12)−0.0023 (14)
C320.0407 (13)0.081 (2)0.0817 (19)−0.0074 (13)0.0020 (13)0.0100 (16)

Geometric parameters (Å, °)

O2—C21.240 (3)C31—C321.489 (4)
O3—C311.218 (3)C4—H40.9500
O11—C121.195 (3)C5—H50.9500
O12—C121.316 (3)C6—H60.9500
O12—C131.490 (3)C11—H1110.9500
N1—C21.378 (3)C11—H1120.9500
N1—C61.377 (3)C14—H14A0.9600
N1—C111.453 (3)C14—H14B0.9600
N3—C31.399 (3)C14—H14C0.9600
N3—C311.362 (3)C15—H15A0.9600
N3—H30.8600C15—H15B0.9600
C2—C31.450 (3)C15—H15C0.9600
C3—C41.361 (3)C16—H16A0.9600
C4—C51.402 (4)C16—H16B0.9600
C5—C61.333 (4)C16—H16C0.9600
C11—C121.512 (3)C32—H32A0.9600
C13—C141.507 (4)C32—H32B0.9600
C13—C161.494 (4)C32—H32C0.9600
C13—C151.503 (4)
O2···N32.694 (2)C31···H42.7800
O2···C123.233 (3)C32···H112i3.0200
O2···C32i3.222 (3)H3···O22.3100
O2···N3i3.164 (3)H3···H32C2.1500
O3···C42.830 (3)H3···O2i2.3400
O11···C23.130 (3)H4···O32.2300
O11···N12.744 (3)H4···C312.7800
O11···C152.980 (4)H4···O11vi2.8200
O11···C162.978 (5)H5···O11vi2.7100
O11···C5ii3.319 (4)H5···C5vi3.0500
O11···C4ii3.379 (3)H5···C6vi3.0200
O2···H32.3100H6···O11vii2.7200
O2···H32Ci2.3300H6···H1112.3100
O2···H1122.4200H6···C4vi3.0300
O2···H3i2.3400H14A···O3viii2.5600
O3···H42.2300H14A···H15C2.4600
O3···H14Aiii2.5600H14A···H16B2.5100
O3···H15Bii2.8800H14B···C16vii2.9800
O11···H16A2.4400H14B···H15B2.5100
O11···H6iv2.7200H14B···H16Bvii2.3100
O11···H15A2.4400H14C···H16C2.4600
O11···H4ii2.8200H15A···O112.4400
O11···H5ii2.7100H15A···C122.7900
N1···O112.744 (3)H15A···H16A2.4200
N3···O22.694 (2)H15B···C123.0800
N3···O2i3.164 (3)H15B···H14B2.5100
N3···H112v2.9400H15B···O3vi2.8800
C2···O113.130 (3)H15C···H14A2.4600
C2···C2v3.441 (3)H16A···O112.4400
C4···O32.830 (3)H16A···C122.8300
C4···O11vi3.379 (3)H16A···H15A2.4200
C5···O11vi3.319 (4)H16B···H14A2.5100
C12···O23.233 (3)H16B···H14Biv2.3100
C15···O112.980 (4)H16C···H14C2.4600
C16···O112.978 (5)H32B···C4iv3.0800
C32···O2i3.222 (3)H32C···H32.1500
C4···H32Bvii3.0800H32C···O2i2.3300
C4···H6ii3.0300H32C···C11i3.0300
C5···H5ii3.0500H32C···C12i3.0900
C6···H5ii3.0200H32C···H112i2.3400
C11···H32Ci3.0300H111···H62.3100
C12···H15A2.7900H112···O22.4200
C12···H32Ci3.0900H112···N3v2.9400
C12···H16A2.8300H112···C32i3.0200
C12···H15B3.0800H112···H32Ci2.3400
C16···H14Biv2.9800
C12—O12—C13121.10 (18)C6—C5—H5120.00
C2—N1—C6123.04 (19)N1—C6—H6120.00
C2—N1—C11117.79 (18)C5—C6—H6120.00
C6—N1—C11119.00 (19)N1—C11—H111109.00
C3—N3—C31126.7 (2)N1—C11—H112109.00
C3—N3—H3117.00C12—C11—H111109.00
C31—N3—H3117.00C12—C11—H112109.00
N1—C2—C3115.51 (19)H111—C11—H112109.00
O2—C2—N1120.98 (19)C13—C14—H14A109.00
O2—C2—C3123.5 (2)C13—C14—H14B109.00
N3—C3—C2113.04 (19)C13—C14—H14C109.00
N3—C3—C4126.5 (2)H14A—C14—H14B110.00
C2—C3—C4120.5 (2)H14A—C14—H14C109.00
C3—C4—C5120.4 (2)H14B—C14—H14C109.00
C4—C5—C6120.0 (3)C13—C15—H15A110.00
N1—C6—C5120.6 (2)C13—C15—H15B109.00
N1—C11—C12111.23 (19)C13—C15—H15C110.00
O11—C12—C11124.2 (2)H15A—C15—H15B109.00
O11—C12—O12125.7 (2)H15A—C15—H15C109.00
O12—C12—C11110.02 (19)H15B—C15—H15C109.00
O12—C13—C15108.9 (2)C13—C16—H16A109.00
O12—C13—C14103.0 (2)C13—C16—H16B109.00
C14—C13—C16110.8 (3)C13—C16—H16C109.00
C15—C13—C16113.3 (3)H16A—C16—H16B109.00
O12—C13—C16109.9 (2)H16A—C16—H16C109.00
C14—C13—C15110.5 (2)H16B—C16—H16C109.00
N3—C31—C32115.7 (2)C31—C32—H32A109.00
O3—C31—N3122.5 (2)C31—C32—H32B109.00
O3—C31—C32121.8 (2)C31—C32—H32C109.00
C3—C4—H4120.00H32A—C32—H32B109.00
C5—C4—H4120.00H32A—C32—H32C109.00
C4—C5—H5120.00H32B—C32—H32C110.00
C13—O12—C12—O11−5.0 (4)C31—N3—C3—C41.5 (4)
C13—O12—C12—C11175.59 (19)C3—N3—C31—O31.4 (4)
C12—O12—C13—C14−177.9 (2)C3—N3—C31—C32−179.6 (2)
C12—O12—C13—C15−60.6 (3)O2—C2—C3—N3−1.0 (3)
C12—O12—C13—C1664.0 (3)O2—C2—C3—C4178.7 (2)
C6—N1—C2—O2−180.0 (2)N1—C2—C3—N3178.89 (19)
C6—N1—C2—C30.2 (3)N1—C2—C3—C4−1.4 (3)
C11—N1—C2—O2−4.9 (3)N3—C3—C4—C5−178.3 (2)
C11—N1—C2—C3175.25 (19)C2—C3—C4—C52.0 (4)
C2—N1—C6—C50.6 (4)C3—C4—C5—C6−1.3 (4)
C11—N1—C6—C5−174.5 (2)C4—C5—C6—N10.0 (4)
C2—N1—C11—C12−81.1 (2)N1—C11—C12—O1111.0 (3)
C6—N1—C11—C1294.2 (2)N1—C11—C12—O12−169.61 (18)
C31—N3—C3—C2−178.8 (2)

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

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N3—H3···O2i0.86002.34003.164 (3)161.00
C4—H4···O30.95002.23002.830 (3)120.00
C14—H14A···O3viii0.962.563.465 (4)157
C15—H15A···O110.962.442.980 (4)115
C16—H16A···O110.962.442.978 (5)115
C32—H32C···O2i0.962.333.222 (3)155

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT2816).

References

  • Bernstein, P. R., Andisik, D., Bradley, P. K., Bryant, C. B., Ceccarelli, C., Damewood, J. R. Jr, Earley, R., Edwards, P. D., Feeney, S., Gomes, B. C., Kosmider, B. J., Steelman, G. B., Thomas, R. M., Vacek, E. P., Veale, C. A., Williams, J. C., Wolanin, D. J. & Woolson, S. A. (1994). J. Med. Chem.37, 3313–3326. [PubMed]
  • Dragovich, P. S., Prins, T. J., Zhou, R., Brown, E. L., Maldonado, F. C., Fuhrman, S. A., Zalman, L. S., Tuntland, T., Lee, C. A., Patick, A. K., Matthews, D. A., Hendrickson, T. F., Kosa, M. B., Liu, B., Batugo, M. R., Gleeson, J.-P. R., Sakata, S. K., Chen, L., Guzman, M. C., Meador, J. W., Ferre, R. A. & Worland, S. T. (2002). J. Med. Chem.45, 1607–1623. [PubMed]
  • Farrugia, L. J. (1997). J. Appl. Cryst.30, 565.
  • Hu, E., Tasker, A., White, R. D., Kunz, R. K., Human, J., Chen, N., Burli, R., Hungate, R., Novak, P., Itano, A., Zhang, X., Yu, V., Nguyen, Y., Tudor, Y., Plant, M., Flynn, S., Xu, Y., Meagher, K. L., Whittington, D. A. & Ng, G. Y. (2008). J. Med. Chem.51, 3065–3068. [PubMed]
  • Karis, N. D., Loughlin, W. A. & Jenkins, I. D. (2007). Tetrahedron, 63, 12303–12309.
  • Karis, N. D., Loughlin, W. A., Jenkins, I. D. & Healy, P. C. (2006). Acta Cryst. E62, o2714–o2716.
  • Kim, K. S., Zhang, L., Schmidt, R., Cai, Z.-W., Wei, D., Williams, D. K., Lombardo, L. J., Trainor, G. L., Xie, D., Zhang, Y., An, Y., Sack, J. S., Tokarski, J. S., Darienzo, C., Kamath, A., Marathe, P., Zhang, Y., Lippy, J., Jeyaseelan, R., Wautlet, B., Henley, B., Gullo-Brown, J., Manne, V., Hunt, J. T., Fargnoli, J. & Borzilleri, R. M. (2008). J. Med. Chem.51, 5330–5341. [PubMed]
  • Loughlin, W. A., Tyndall, J. D. A., Glenn, M. P. & Fairlie, D. P. (2004). Chem. Rev.104, 6085–6117. [PubMed]
  • Molecular Structure Corporation (1999). MSC/AFC7 Diffractometer Control for Windows MSC, The Woodlands, Texas, USA.
  • Molecular Structure Corporation. (2001). TEXSAN for Windows MSC, The Woodlands, Texas, USA.
  • Reiner, J. E., Lim-Wilby, M. S., Brunck, T. K., Ha-Uong, T., Goldman, E. A., Abelman, M. A., Nutt, R. F., Semple, J. E. & Tamura, S. Y. (1999). Bioorg. Med. Chem. Lett.9, 895–900. [PubMed]
  • Sanderson, P. E., Naylor-Olsen, A. M., Dyer, D. L., Vacca, J. P., Isaacs, R. C. A., Dorsey, B. D. & Frayler, M. E. (1997). PCT Int. Appl. WO 9 701 338.
  • Semple, G., Ashwoth, D. M., Batt, A. R., Baxter, A. J., Benzies, D. W. M., Elliot, L. H., Evans, D. M., Franklin, R. J., Hudson, P., Jenkins, P. D., Pitt, G. R., Rooker, D. P., Yamamoto, S. & Isomura, Y. (1998). Bioorg. Med. Chem. Lett.8, 959–964. [PubMed]
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Spek, A. L. (2003). J. Appl. Cryst.36, 7–13.
  • Tamura, S. Y., Semple, J. E., Ripka, W. C., Ardecky, R. J., Ge, Y., Carpenter, S. H., Brunck, T. K., Lim-Wilby, M. S., Nutt, R. F. & Abelman, M. M. (1996). PCT Int. Appl. WO 9 618 644.
  • Veale, C. A., Bernstein, P. R., Bryant, C., Ceccarelli, C., Damewood, J. R. Jr, Earley, R., Feeney, S. W., Gomes, B., Kosmider, B. J., Steelman, G. B., Thomas, R. M., Vacek, E. P., Williams, J. C., Wolanin, D. J. & Woolson, S. A. (1995). J. Med. Chem.38, 98–108. [PubMed]
  • Yang, H. W. & Craven, B. M. (1998). Acta Cryst. B54, 912–920. [PubMed]

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