3-(3-Chloro­anilino)-1-(3,5-dimethyl-1H-pyrazol-1-yl)propan-1-one

Saeed, A.; Hussain, S.; Bolte, M.

doi:10.1107/S1600536809016250

organic compounds

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ISSN: 2056-9890

Volume 65| Part 6| June 2009| Page o1231

doi:10.1107/S1600536809016250

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3-(3-Chloroanilino)-1-(3,5-dimethyl-1H-pyrazol-1-yl)propan-1-one

Aamer Saeed,^a Shahid Hussain ^a and Michael Bolte ^b ^*

^aDepartment of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan, and ^bInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt/Main, Germany
^*Correspondence e-mail: aamersaeed@yahoo.com

(Received 29 April 2009; accepted 30 April 2009; online 7 May 2009)

In the molecule of the title compound, C₁₄H₁₆ClN₃O, the benzene and pyrazole rings are oriented at a dihedral angle of 3.50 (3)°. In the crystal structure, intermolecular N—H⋯O hydrogen bonds link the molecules into chains. A π–π contact between the benzene and pyrazole rings [centroid–centroid distance = 3.820 (3) Å] may further stabilize the structure.

Related literature

For general background to 1,3,5-trisubstituted pyrazoles, see: Elguero & Goya (2002 ). The pyrazole chemotype is the structural motif of several highly potent inhibitors against coagulation factor Xa, see: Penning & Talley (1997 ); Eriksson & Quinlan (2006 ); Escolar et al. (2006 ). Pyrazole 3-carboxylates have been identified as selective antagonist subtype 1PGE2 receptors (Akarca, 2005 ) and pyrazole-based materials have been used as co-polymers for electroluminescent applications (Mella & Fagnoni, 1997 ). For the synthesis, see: Saeed & Mumtaz (2008 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₄H₁₆ClN₃O
M_r = 277.75
Monoclinic, P 2₁ /c
a = 14.5389 (8) Å
b = 7.8731 (6) Å
c = 12.1411 (7) Å
β = 102.566 (5)°
V = 1356.46 (15) Å³
Z = 4
Mo Kα radiation
μ = 0.28 mm⁻¹
T = 173 K
0.35 × 0.33 × 0.33 mm

Data collection

Stoe IPDS II two-circle diffractometer
Absorption correction: multi-scan (MULABS; Blessing, 1995 ) T_min = 0.909, T_max = 0.914
8907 measured reflections
2528 independent reflections
2192 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.031
wR(F²) = 0.086
S = 1.06
2528 reflections
179 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.828 (18)	2.293 (19)	3.1101 (15)	169.1 (16)
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: X-AREA (Stoe & Cie, 2001 ); cell refinement: X-RED (Stoe & Cie, 2001); data reduction: X-RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809016250/hk2680sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809016250/hk2680Isup2.hkl

checkCIF report

Comment top

1,3,5-Trisubstituted pyrazoles are synthetic targets of paramount significance in the pharmacological industry, in view of the fact that such a heterocyclic moiety represents the core structure of numerous drugs including the widely prescribed Celebrex and Viagra (Elguero & Goya, 2002). Pyrazole chemotype is structural motif of several highly potent inhibitors against coagulation factor Xa (Penning & Talley, 1997) among them Rivaroxaban (Eriksson & Quinlan, 2006) and Apixaban (Escolar et al., 2006) were selected for clinical development for the prevention and treatment of thrombotic diseases. Pyrazole 3-carboxylates were also identified as selective antagonist subtype 1PGE2 receptors (Akarca, 2005). The pyrazole-based materials have been used as co-polymers for electroluminescent applications (Mella & Fagnoni, 1997). We report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Rings A (C11-C16) and B (N21/N22/C23-C25) are, of course, planar, and they are oriented at a dihedral angle of A/B = 3.50 (3)°.

In the crystal structure, intermolecular N-H···O hydrogen bonds (Table 1) link the molecules into chains (Fig. 2), in which they may be effective in the stabilization of the structure. The π–π contact between the phenyl ring and the pyrazole ring, Cg1—Cg2ⁱ [symmetry code: (i) 1 - x, 1 - y, -z, where Cg1 and Cg2 are centroids of the rings A (C11-C16) and B (N21/N22/C23-C25), respectively] may further stabilize the structure, with centroid-centroid distance of 3.820 (3) Å.

Related literature top

For general background to 1,3,5-trisubstituted pyrazoles, see: Elguero & Goya (2002). The pyrazole chemotype is the structural motif of several highly potent inhibitors against coagulation factor Xa, see: Penning & Talley (1997); Eriksson & Quinlan (2006); Escolar et al. (2006). Pyrazole 3-carboxylates have been identified as selective antagonist subtype 1PGE2 receptors (Akarca, 2005) and pyrazole-based materials have been used as co-polymers for electroluminescent applications (Mella & Fagnoni, 1997). For a related structure, see: Saeed & Mumtaz (2008). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound was prepared by cyclocondensation of pentane-2,4-dione with corresponding 3-(3-Chlorophenylamino) propionohydrazide according to a method reported earlier (Saeed & Mumtaz, 2008). Recrystallization from methanol afforded the title compound (yield; 81%). Anal. calcd. for C₁₄H₁₆ClN₃O: C, 60.54; H, 5.81; N, 15.13%; found: C, 60.51; H, 5.83; N, 15.07%.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-RED (Stoe & Cie, 2001); data reduction: X-RED (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

3-(3-Chloroanilino)-1-(3,5-dimethyl-1H-pyrazol-1-yl)propan-1-one top

Crystal data top

C₁₄H₁₆ClN₃O	F(000) = 584
M_r = 277.75	D_x = 1.360 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 8296 reflections
a = 14.5389 (8) Å	θ = 3.5–25.9°
b = 7.8731 (6) Å	µ = 0.28 mm⁻¹
c = 12.1411 (7) Å	T = 173 K
β = 102.566 (5)°	Block, orange
V = 1356.46 (15) Å³	0.35 × 0.33 × 0.33 mm
Z = 4

Data collection top

Stoe IPDS II two-circle diffractometer	2528 independent reflections
Radiation source: fine-focus sealed tube	2192 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ω scans	θ_max = 25.6°, θ_min = 3.4°
Absorption correction: multi-scan (MULABS; Blessing, 1995)	h = −17→16
T_min = 0.909, T_max = 0.914	k = −9→8
8907 measured reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.031	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.086	w = 1/[σ²(F_o²) + (0.0525P)² + 0.155P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
2528 reflections	Δρ_max = 0.22 e Å⁻³
179 parameters	Δρ_min = −0.23 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0118 (15)

Crystal data top

C₁₄H₁₆ClN₃O	V = 1356.46 (15) Å³
M_r = 277.75	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.5389 (8) Å	µ = 0.28 mm⁻¹
b = 7.8731 (6) Å	T = 173 K
c = 12.1411 (7) Å	0.35 × 0.33 × 0.33 mm
β = 102.566 (5)°

Data collection top

Stoe IPDS II two-circle diffractometer	2528 independent reflections
Absorption correction: multi-scan (MULABS; Blessing, 1995)	2192 reflections with I > 2σ(I)
T_min = 0.909, T_max = 0.914	R_int = 0.034
8907 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.031	0 restraints
wR(F²) = 0.086	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.22 e Å⁻³
2528 reflections	Δρ_min = −0.23 e Å⁻³
179 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

	x	y	z	U_iso*/U_eq
Cl1	0.09245 (2)	0.19275 (5)	0.40578 (3)	0.03790 (14)
O1	0.56854 (7)	0.37061 (15)	0.32982 (8)	0.0338 (3)
N1	0.44533 (8)	0.16939 (17)	0.58746 (10)	0.0303 (3)
H1	0.4841 (13)	0.165 (2)	0.6485 (15)	0.035 (4)*
C1	0.47221 (8)	0.24939 (17)	0.49191 (10)	0.0230 (3)
H1A	0.4458	0.3656	0.4810	0.028*
H1B	0.4478	0.1831	0.4224	0.028*
C2	0.57897 (9)	0.25608 (17)	0.51596 (10)	0.0224 (3)
H2A	0.6019	0.3236	0.5853	0.027*
H2B	0.6041	0.1394	0.5304	0.027*
C3	0.61688 (9)	0.33260 (16)	0.42090 (10)	0.0218 (3)
C11	0.35323 (9)	0.13937 (17)	0.59318 (10)	0.0224 (3)
C12	0.27731 (9)	0.18284 (17)	0.50608 (10)	0.0232 (3)
H12	0.2873	0.2407	0.4410	0.028*
C13	0.18671 (9)	0.13994 (18)	0.51620 (11)	0.0261 (3)
C14	0.16813 (10)	0.0571 (2)	0.60922 (12)	0.0319 (3)
H14	0.1056	0.0281	0.6135	0.038*
C15	0.24443 (10)	0.01754 (19)	0.69646 (12)	0.0321 (3)
H15	0.2337	−0.0378	0.7620	0.039*
C16	0.33520 (10)	0.05718 (18)	0.68943 (11)	0.0270 (3)
H16	0.3862	0.0289	0.7500	0.032*
N21	0.71440 (8)	0.35624 (14)	0.44523 (8)	0.0211 (2)
N22	0.76632 (8)	0.30431 (14)	0.54929 (9)	0.0234 (2)
C23	0.85436 (9)	0.33838 (17)	0.54618 (11)	0.0252 (3)
C24	0.86089 (9)	0.41270 (18)	0.44162 (11)	0.0261 (3)
H24	0.9170	0.4479	0.4201	0.031*
C25	0.77205 (9)	0.42387 (16)	0.37845 (10)	0.0228 (3)
C26	0.93179 (10)	0.3031 (2)	0.64623 (13)	0.0374 (4)
H26A	0.9551	0.4104	0.6828	0.056*
H26B	0.9833	0.2441	0.6219	0.056*
H26C	0.9078	0.2315	0.6998	0.056*
C27	0.73737 (10)	0.49322 (19)	0.26314 (11)	0.0310 (3)
H27A	0.7888	0.5528	0.2390	0.046*
H27B	0.6855	0.5726	0.2636	0.046*
H27C	0.7149	0.3999	0.2107	0.046*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.01956 (19)	0.0532 (3)	0.0377 (2)	0.00375 (15)	−0.00099 (14)	−0.00656 (16)
O1	0.0241 (5)	0.0519 (7)	0.0233 (5)	−0.0005 (5)	0.0006 (4)	0.0057 (4)
N1	0.0177 (6)	0.0487 (8)	0.0228 (6)	−0.0042 (5)	0.0009 (5)	0.0071 (5)
C1	0.0182 (6)	0.0276 (7)	0.0228 (6)	−0.0011 (5)	0.0033 (5)	0.0014 (5)
C2	0.0181 (6)	0.0255 (7)	0.0227 (6)	−0.0010 (5)	0.0029 (5)	0.0007 (5)
C3	0.0197 (6)	0.0242 (7)	0.0209 (6)	0.0003 (5)	0.0030 (5)	−0.0023 (5)
C11	0.0203 (6)	0.0229 (6)	0.0243 (6)	−0.0023 (5)	0.0056 (5)	−0.0041 (5)
C12	0.0211 (6)	0.0259 (7)	0.0229 (6)	−0.0003 (5)	0.0055 (5)	−0.0026 (5)
C13	0.0194 (6)	0.0290 (7)	0.0292 (6)	0.0005 (5)	0.0038 (5)	−0.0078 (5)
C14	0.0234 (7)	0.0352 (8)	0.0401 (8)	−0.0051 (6)	0.0135 (6)	−0.0043 (6)
C15	0.0331 (8)	0.0337 (8)	0.0328 (7)	−0.0028 (6)	0.0145 (6)	0.0030 (6)
C16	0.0274 (7)	0.0286 (7)	0.0250 (6)	−0.0010 (6)	0.0058 (5)	0.0015 (5)
N21	0.0197 (5)	0.0255 (6)	0.0183 (5)	−0.0011 (4)	0.0044 (4)	0.0000 (4)
N22	0.0195 (5)	0.0299 (6)	0.0199 (5)	0.0003 (5)	0.0021 (4)	0.0019 (4)
C23	0.0193 (6)	0.0296 (7)	0.0263 (6)	0.0005 (5)	0.0042 (5)	−0.0025 (5)
C24	0.0222 (6)	0.0303 (7)	0.0279 (7)	−0.0047 (6)	0.0102 (5)	−0.0028 (5)
C25	0.0261 (6)	0.0215 (6)	0.0231 (6)	−0.0031 (5)	0.0104 (5)	−0.0032 (5)
C26	0.0199 (7)	0.0555 (10)	0.0345 (8)	0.0007 (7)	0.0012 (6)	0.0059 (7)
C27	0.0347 (7)	0.0370 (8)	0.0226 (6)	−0.0034 (6)	0.0090 (6)	0.0028 (6)

Geometric parameters (Å, º) top

Cl1—C13	1.7461 (14)	C14—H14	0.9500
O1—C3	1.2116 (16)	C15—C16	1.3767 (19)
N1—C11	1.3762 (17)	C15—H15	0.9500
N1—C1	1.4466 (16)	C16—H16	0.9500
N1—H1	0.828 (18)	N21—N22	1.3850 (15)
C1—C2	1.5165 (17)	N21—C25	1.3925 (16)
C1—H1A	0.9900	N22—C23	1.3164 (17)
C1—H1B	0.9900	C23—C24	1.4197 (18)
C2—C3	1.5085 (17)	C23—C26	1.4916 (19)
C2—H2A	0.9900	C24—C25	1.3540 (19)
C2—H2B	0.9900	C24—H24	0.9500
C3—N21	1.3964 (17)	C25—C27	1.4850 (18)
C11—C12	1.3950 (18)	C26—H26A	0.9800
C11—C16	1.4093 (18)	C26—H26B	0.9800
C12—C13	1.3909 (19)	C26—H26C	0.9800
C12—H12	0.9500	C27—H27A	0.9800
C13—C14	1.381 (2)	C27—H27B	0.9800
C14—C15	1.392 (2)	C27—H27C	0.9800

C11—N1—C1	123.43 (12)	C16—C15—H15	119.4
C11—N1—H1	115.4 (12)	C14—C15—H15	119.4
C1—N1—H1	119.0 (12)	C15—C16—C11	120.61 (13)
N1—C1—C2	107.73 (10)	C15—C16—H16	119.7
N1—C1—H1A	110.2	C11—C16—H16	119.7
C2—C1—H1A	110.2	N22—N21—C25	111.49 (10)
N1—C1—H1B	110.2	N22—N21—C3	118.72 (10)
C2—C1—H1B	110.2	C25—N21—C3	129.78 (11)
H1A—C1—H1B	108.5	C23—N22—N21	104.72 (10)
C3—C2—C1	113.30 (10)	N22—C23—C24	111.36 (11)
C3—C2—H2A	108.9	N22—C23—C26	120.32 (12)
C1—C2—H2A	108.9	C24—C23—C26	128.29 (12)
C3—C2—H2B	108.9	C25—C24—C23	106.98 (11)
C1—C2—H2B	108.9	C25—C24—H24	126.5
H2A—C2—H2B	107.7	C23—C24—H24	126.5
O1—C3—N21	121.39 (11)	C24—C25—N21	105.44 (11)
O1—C3—C2	124.12 (12)	C24—C25—C27	130.10 (12)
N21—C3—C2	114.49 (10)	N21—C25—C27	124.45 (12)
N1—C11—C12	122.53 (12)	C23—C26—H26A	109.5
N1—C11—C16	118.64 (12)	C23—C26—H26B	109.5
C12—C11—C16	118.81 (12)	H26A—C26—H26B	109.5
C13—C12—C11	118.80 (12)	C23—C26—H26C	109.5
C13—C12—H12	120.6	H26A—C26—H26C	109.5
C11—C12—H12	120.6	H26B—C26—H26C	109.5
C14—C13—C12	122.99 (13)	C25—C27—H27A	109.5
C14—C13—Cl1	118.68 (11)	C25—C27—H27B	109.5
C12—C13—Cl1	118.33 (11)	H27A—C27—H27B	109.5
C13—C14—C15	117.55 (13)	C25—C27—H27C	109.5
C13—C14—H14	121.2	H27A—C27—H27C	109.5
C15—C14—H14	121.2	H27B—C27—H27C	109.5
C16—C15—C14	121.21 (13)

C11—N1—C1—C2	−178.65 (12)	O1—C3—N21—N22	−177.55 (12)
N1—C1—C2—C3	178.34 (11)	C2—C3—N21—N22	1.99 (16)
C1—C2—C3—O1	−6.68 (19)	O1—C3—N21—C25	1.0 (2)
C1—C2—C3—N21	173.80 (11)	C2—C3—N21—C25	−179.47 (12)
C1—N1—C11—C12	0.5 (2)	C25—N21—N22—C23	−0.40 (14)
C1—N1—C11—C16	178.65 (13)	C3—N21—N22—C23	178.39 (11)
N1—C11—C12—C13	176.66 (12)	N21—N22—C23—C24	0.26 (15)
C16—C11—C12—C13	−1.49 (19)	N21—N22—C23—C26	178.52 (12)
C11—C12—C13—C14	0.5 (2)	N22—C23—C24—C25	−0.02 (16)
C11—C12—C13—Cl1	−179.22 (10)	C26—C23—C24—C25	−178.12 (14)
C12—C13—C14—C15	0.7 (2)	C23—C24—C25—N21	−0.22 (14)
Cl1—C13—C14—C15	−179.52 (11)	C23—C24—C25—C27	179.06 (13)
C13—C14—C15—C16	−1.0 (2)	N22—N21—C25—C24	0.39 (14)
C14—C15—C16—C11	0.0 (2)	C3—N21—C25—C24	−178.23 (12)
N1—C11—C16—C15	−176.98 (13)	N22—N21—C25—C27	−178.94 (12)
C12—C11—C16—C15	1.2 (2)	C3—N21—C25—C27	2.4 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.828 (18)	2.293 (19)	3.1101 (15)	169.1 (16)

Symmetry code: (i) x, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₆ClN₃O
M_r	277.75
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	14.5389 (8), 7.8731 (6), 12.1411 (7)
β (°)	102.566 (5)
V (Å³)	1356.46 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.28
Crystal size (mm)	0.35 × 0.33 × 0.33

Data collection
Diffractometer	Stoe IPDS II two-circle diffractometer
Absorption correction	Multi-scan (MULABS; Blessing, 1995)
T_min, T_max	0.909, 0.914
No. of measured, independent and observed [I > 2σ(I)] reflections	8907, 2528, 2192
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.086, 1.06
No. of reflections	2528
No. of parameters	179
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.23

Computer programs: X-AREA (Stoe & Cie, 2001), X-RED (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.828 (18)	2.293 (19)	3.1101 (15)	169.1 (16)

Symmetry code: (i) x, −y+1/2, z+1/2.

Acknowledgements

AS gratefully acknowledges a research grant from Quaid-i-Azam University, Islamabad, under the URF project No. DFNS/2009-36.

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