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

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ISSN: 2414-3146

(4Z)-4-[1-(2-Amino­anilino)ethyl­­idene]-3-methyl-1-phenyl-4,5-di­hydro-1H-pyrazol-5-one

aLaboratoire de Chimie Organique Heterocyclique, Faculté des Sciences, Mohammed V University, Rabat, Morocco, bUnité de Chimie Moleculaire et Environnement, Faculté des Sciences et Techniques, Université de Sciences, de Technologie et de Medecine Nouakchott, Mauritania, cLaboratory of Medicinal Chemistry, Faculty of Medicine and Pharmacy, Mohammed V University, Rabat, Morocco, and dDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
*Correspondence e-mail: mohamed_samba77@yahoo.com

Edited by J. Simpson, University of Otago, New Zealand (Received 4 February 2017; accepted 14 February 2017; online 17 February 2017)

The conformation of the title compound, C18H18N4O, is partly determined by an intra­molecular N—H⋯O hydrogen bond that imposes planarity on the central amino­ethyl­idene-3-methyl­pyrazol-5-one segment of the mol­ecule. In the crystal, N—H⋯O hydrogen and N—H⋯N hydrogen bonds both form centrosymmetric dimers that enclose R22(18) rings. These, together with C—H⋯N and ππ stacking inter­actions between centrosymmetrically related pyraza­lone rings, stack the mol­ecules along the b-axis direction.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Pyrazole derivatives are known to possess a broad spectrum of biological activities, acting as cannabinoid receptor antagonists (Lan et al., 1999[Lan, R., Liu, Q., Fan, P., Lin, S., Fernando, S. R., McCallion, D., Pertwee, R. & Makriyannis, A. (1999). J. Med. Chem. 42, 769-776.]), anti­bacterial (Tanitame et al., 2004[Tanitame, A., Oyamada, Y., Ofuji, K., Fujimoto, M., Iwai, N., Hiyama, Y., Suzuki, K., Ito, H., Terauchi, H., Kawasaki, M., Nagai, K., Wachi, M. & Yamagishi, J.-I. (2004). J. Med. Chem. 47, 3693-3696.]), anti-inflammatory and anti­microbial agents (Bekhit & Abdel-Aziem, 2004[Bekhit, A. A. & Abdel-Aziem, T. (2004). Bioorg. Med. Chem. 12, 1935-1945.]). In a continuation of our research using acetoacetyl pyrazole as starting material in the synthesis of several heterocyclic systems with potent pharmacological properties (Djerrari et al., 2001[Djerrari, B., Essassi, E. M., Fifani, J. & Pierrot, M. (2001). Acta Cryst. E57, o1126-o1127.],2003[Djerrari, B., Fifani, J., Ahabchane, N. H., Essassi, E. M. & Pierrot, M. (2003). Indian J. Chem. Sect. B, 42, 2558-2562.]), we report in this work the crystal structure of the title pyrazolone derivative.

The conformation of the title mol­ecule is partially determined by an intra­molecular N3—H3⋯O1 hydrogen bond (Table 1[link], Figs. 1[link] and 2[link]). This ensures the planarity of the central C13/N3/C12(C11)[N1,N2,C1(C10)C2,C3(O1)] section of the mol­ecule, r.m.s. deviation 0.0403 Å. The dihedral angle between the mean planes of the N1/N2/C1–C3 and C4–C9 rings is 21.31 (4)° while that between the former ring and the C13—C18 ring is 62.60 (5)°.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3⋯O1 0.955 (18) 1.863 (18) 2.6965 (14) 144.3 (15)
N4—H4A⋯N2i 0.92 (2) 2.47 (2) 3.2542 (17) 144.1 (16)
N4—H4B⋯O1ii 0.93 (2) 2.14 (2) 3.0090 (16) 153.3 (17)
C9—H9⋯N4i 1.008 (17) 2.567 (17) 3.571 (2) 173.7 (13)
C11—H11C⋯N1iii 0.98 (2) 2.68 (2) 3.5669 (19) 152.0 (16)
C18—H18⋯N2iii 0.997 (17) 2.439 (17) 3.3984 (18) 161.2 (13)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x, -y+1, -z+1; (iii) -x+1, -y+2, -z+1.
[Figure 1]
Figure 1
The title mol­ecule with the labelling scheme and 50% probability displacement ellipsoids. The intra­molecular hydrogen bond is shown as a dashed line.
[Figure 2]
Figure 2
Detail of the intra- and inter­molecular mol­ecular inter­actions (dashed lines: N—H⋯O, blue; N—H⋯N, purple; C—H⋯O; black; ππ stacking, orange). For symmetry codes, see Table 1[link].

In the crystal, the mol­ecules form centrosymmetric dimers through pairwise N4—H4B⋯O1ii hydrogen bonds, Table 1[link]. N1—H4A⋯N2i hydrogen bonds also form inversion dimers with both sets of dimers forming R22(18) ring motifs. The dimers stack along the b-axis direction aided by C9—H9⋯N4i, C11—H11C⋯N1iii and C18—H18⋯N2iii hydrogen bonds and offset ππ-stacking inter­actions [Cg1⋯Cg1iv = 3.758 (1) Å; symmetry code: (iv) 1 − x, 1 − y, 1 − z] between pairs of centrosymmetrically related pyrazolone rings (Table 1[link], Figs. 2[link] and 3[link]). The individual stacks show only normal van der Waals contacts between them.

[Figure 3]
Figure 3
Crystal packing, viewed along the a axis (the colour codes for the hydrogen bonds are given in Fig. 2[link]).

Synthesis and crystallization

To a solution of acetoacetyl pyrazole (0.001 mol) in 40 ml of ethanol was added o-phenyl­enedi­amine (0.002 mol). The reaction mixture was refluxed for 2 h. After cooling, the solvent was removed under reduced pressure. The residue obtained was recrystallized from ethanol to afford colourless block-like crystals of the title compound (m.p. 485–487 K, yield: 80%).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C18H18N4O
Mr 306.36
Crystal system, space group Monoclinic, P21/c
Temperature (K) 150
a, b, c (Å) 8.6575 (2), 7.1749 (1), 25.3062 (5)
β (°) 93.782 (1)
V3) 1568.51 (5)
Z 4
Radiation type Cu Kα
μ (mm−1) 0.67
Crystal size (mm) 0.19 × 0.05 × 0.05
 
Data collection
Diffractometer Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction Multi-scan (SADABS; Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.87, 0.97
No. of measured, independent and observed [I > 2σ(I)] reflections 11756, 3032, 2596
Rint 0.035
(sin θ/λ)max−1) 0.618
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.096, 1.04
No. of reflections 3032
No. of parameters 281
H-atom treatment All H-atom parameters refined
Δρmax, Δρmin (e Å−3) 0.29, −0.18
Computer programs: APEX3 and SAINT (Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2014 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Structural data


Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

(4Z)-4-[1-(2-Aminoanilino)ethylidene]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one top
Crystal data top
C18H18N4OF(000) = 648
Mr = 306.36Dx = 1.297 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
a = 8.6575 (2) ÅCell parameters from 8108 reflections
b = 7.1749 (1) Åθ = 5.1–72.4°
c = 25.3062 (5) ŵ = 0.67 mm1
β = 93.782 (1)°T = 150 K
V = 1568.51 (5) Å3Column, colourless
Z = 40.19 × 0.05 × 0.05 mm
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
3032 independent reflections
Radiation source: INCOATEC IµS micro-focus source2596 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.035
Detector resolution: 10.4167 pixels mm-1θmax = 72.4°, θmin = 5.1°
ω scansh = 1010
Absorption correction: multi-scan
(SADABS; Bruker, 2016)
k = 88
Tmin = 0.87, Tmax = 0.97l = 3130
11756 measured reflections
Refinement top
Refinement on F2Hydrogen site location: difference Fourier map
Least-squares matrix: fullAll H-atom parameters refined
R[F2 > 2σ(F2)] = 0.038 w = 1/[σ2(Fo2) + (0.0455P)2 + 0.4468P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.096(Δ/σ)max < 0.001
S = 1.04Δρmax = 0.29 e Å3
3032 reflectionsΔρmin = 0.18 e Å3
281 parametersExtinction correction: SHELXL2014 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0050 (4)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O10.23306 (10)0.69400 (14)0.45467 (4)0.0305 (2)
N10.48083 (12)0.71074 (15)0.42251 (4)0.0248 (2)
N20.63327 (12)0.73552 (16)0.44323 (4)0.0270 (3)
N30.25320 (13)0.75094 (16)0.56022 (4)0.0276 (3)
C10.62652 (14)0.75905 (17)0.49448 (5)0.0248 (3)
C20.47020 (14)0.74833 (17)0.50980 (5)0.0234 (3)
C30.37694 (14)0.71531 (17)0.46141 (5)0.0241 (3)
H30.203 (2)0.721 (2)0.5265 (7)0.044 (5)*
C40.45262 (15)0.68737 (17)0.36708 (5)0.0258 (3)
H4A0.132 (2)0.447 (3)0.5721 (8)0.051 (5)*
H4B0.032 (2)0.404 (3)0.5913 (8)0.057 (6)*
N40.05992 (15)0.47138 (18)0.59596 (6)0.0405 (3)
C50.30760 (17)0.7256 (2)0.34286 (5)0.0316 (3)
H50.221 (2)0.771 (2)0.3632 (7)0.040 (4)*
C60.28126 (19)0.6947 (2)0.28880 (6)0.0406 (4)
H60.179 (2)0.722 (3)0.2718 (7)0.047 (5)*
C70.3984 (2)0.6291 (3)0.25907 (6)0.0451 (4)
H70.379 (2)0.604 (3)0.2209 (8)0.057 (5)*
C80.5442 (2)0.5994 (2)0.28307 (6)0.0417 (4)
H80.631 (2)0.552 (3)0.2629 (7)0.052 (5)*
C90.57317 (17)0.6281 (2)0.33724 (6)0.0332 (3)
H90.680 (2)0.607 (2)0.3542 (6)0.037 (4)*
C100.77427 (16)0.7937 (2)0.52661 (6)0.0338 (3)
H10A0.769 (2)0.910 (3)0.5479 (7)0.045 (5)*
H10B0.795 (2)0.693 (3)0.5525 (8)0.054 (5)*
H10C0.862 (2)0.799 (3)0.5015 (8)0.049 (5)*
C110.50207 (16)0.8055 (2)0.60909 (5)0.0294 (3)
H11A0.450 (2)0.766 (3)0.6404 (8)0.056 (5)*
H11B0.601 (2)0.738 (3)0.6094 (8)0.054 (5)*
H11C0.527 (2)0.938 (3)0.6128 (8)0.063 (6)*
C120.40601 (15)0.76834 (17)0.55887 (5)0.0242 (3)
C130.16041 (15)0.78645 (19)0.60397 (5)0.0266 (3)
C140.05963 (14)0.64562 (19)0.61874 (5)0.0284 (3)
C150.04064 (16)0.6879 (2)0.65830 (6)0.0341 (3)
H150.113 (2)0.588 (3)0.6692 (7)0.045 (5)*
C160.04014 (16)0.8615 (2)0.68174 (6)0.0366 (3)
H160.112 (2)0.889 (3)0.7101 (7)0.046 (5)*
C170.06066 (17)0.9995 (2)0.66678 (6)0.0367 (3)
H170.062 (2)1.130 (3)0.6819 (7)0.050 (5)*
C180.15980 (16)0.9615 (2)0.62736 (5)0.0325 (3)
H180.2297 (18)1.060 (2)0.6150 (6)0.037 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0219 (4)0.0418 (6)0.0276 (5)0.0053 (4)0.0004 (3)0.0017 (4)
N10.0222 (5)0.0283 (6)0.0236 (5)0.0018 (4)0.0002 (4)0.0002 (4)
N20.0223 (5)0.0285 (6)0.0301 (6)0.0015 (4)0.0006 (4)0.0002 (5)
N30.0266 (6)0.0329 (6)0.0232 (5)0.0051 (5)0.0022 (4)0.0021 (5)
C10.0243 (6)0.0210 (6)0.0289 (6)0.0004 (5)0.0003 (5)0.0008 (5)
C20.0244 (6)0.0215 (6)0.0243 (6)0.0010 (5)0.0002 (5)0.0003 (5)
C30.0244 (6)0.0226 (6)0.0253 (6)0.0015 (5)0.0016 (5)0.0010 (5)
C40.0325 (7)0.0213 (6)0.0235 (6)0.0048 (5)0.0025 (5)0.0009 (5)
N40.0266 (6)0.0327 (7)0.0626 (9)0.0049 (5)0.0061 (6)0.0072 (6)
C50.0326 (7)0.0354 (8)0.0267 (6)0.0071 (6)0.0006 (5)0.0046 (6)
C60.0432 (8)0.0506 (9)0.0274 (7)0.0149 (7)0.0036 (6)0.0073 (7)
C70.0627 (10)0.0494 (10)0.0233 (7)0.0182 (8)0.0034 (7)0.0001 (7)
C80.0562 (10)0.0385 (9)0.0321 (7)0.0047 (7)0.0146 (7)0.0037 (7)
C90.0386 (8)0.0292 (7)0.0323 (7)0.0000 (6)0.0067 (6)0.0004 (6)
C100.0249 (7)0.0394 (8)0.0363 (7)0.0009 (6)0.0041 (6)0.0039 (7)
C110.0323 (7)0.0300 (7)0.0254 (6)0.0018 (6)0.0021 (5)0.0013 (6)
C120.0275 (6)0.0193 (6)0.0257 (6)0.0019 (5)0.0010 (5)0.0017 (5)
C130.0243 (6)0.0328 (7)0.0229 (6)0.0019 (5)0.0014 (5)0.0021 (5)
C140.0218 (6)0.0303 (7)0.0324 (7)0.0008 (5)0.0032 (5)0.0045 (6)
C150.0246 (6)0.0406 (8)0.0375 (7)0.0016 (6)0.0038 (5)0.0093 (6)
C160.0305 (7)0.0493 (9)0.0309 (7)0.0033 (6)0.0075 (6)0.0031 (7)
C170.0374 (8)0.0386 (8)0.0345 (7)0.0002 (6)0.0060 (6)0.0040 (7)
C180.0337 (7)0.0328 (7)0.0316 (7)0.0057 (6)0.0061 (6)0.0009 (6)
Geometric parameters (Å, º) top
O1—C31.2554 (15)C7—H70.985 (19)
N1—C31.3769 (16)C8—C91.392 (2)
N1—N21.3990 (15)C8—H80.999 (19)
N1—C41.4178 (16)C9—H91.008 (17)
N2—C11.3132 (17)C10—H10A0.99 (2)
N3—C121.3316 (17)C10—H10B0.98 (2)
N3—C131.4330 (16)C10—H10C1.021 (19)
N3—H30.955 (18)C11—C121.4962 (18)
C1—C21.4342 (17)C11—H11A0.98 (2)
C1—C101.4906 (18)C11—H11B0.99 (2)
C2—C121.4007 (17)C11—H11C0.98 (2)
C2—C31.4413 (17)C13—C181.388 (2)
C4—C51.3878 (19)C13—C141.4017 (18)
C4—C91.3945 (19)C14—C151.4007 (19)
N4—C141.3768 (19)C15—C161.380 (2)
N4—H4A0.92 (2)C15—H151.000 (18)
N4—H4B0.93 (2)C16—C171.389 (2)
C5—C61.390 (2)C16—H161.002 (18)
C5—H50.991 (17)C17—C181.385 (2)
C6—C71.385 (2)C17—H171.01 (2)
C6—H60.976 (19)C18—H180.997 (17)
C7—C81.380 (2)
C3—N1—N2111.94 (10)C8—C9—H9119.9 (9)
C3—N1—C4129.21 (11)C4—C9—H9121.1 (9)
N2—N1—C4118.84 (10)C1—C10—H10A111.7 (10)
C1—N2—N1106.51 (10)C1—C10—H10B110.7 (12)
C12—N3—C13127.72 (11)H10A—C10—H10B105.5 (15)
C12—N3—H3112.9 (11)C1—C10—H10C108.2 (11)
C13—N3—H3119.2 (11)H10A—C10—H10C111.5 (14)
N2—C1—C2111.37 (11)H10B—C10—H10C109.2 (15)
N2—C1—C10117.88 (12)C12—C11—H11A112.0 (12)
C2—C1—C10130.74 (12)C12—C11—H11B110.7 (11)
C12—C2—C1132.12 (12)H11A—C11—H11B107.4 (16)
C12—C2—C3122.50 (11)C12—C11—H11C111.3 (12)
C1—C2—C3105.35 (11)H11A—C11—H11C108.4 (16)
O1—C3—N1126.09 (11)H11B—C11—H11C106.8 (16)
O1—C3—C2129.10 (11)N3—C12—C2117.79 (11)
N1—C3—C2104.81 (10)N3—C12—C11119.49 (11)
C5—C4—C9120.57 (13)C2—C12—C11122.72 (12)
C5—C4—N1120.36 (12)C18—C13—C14121.23 (12)
C9—C4—N1119.06 (12)C18—C13—N3120.55 (12)
C14—N4—H4A118.0 (13)C14—C13—N3117.93 (12)
C14—N4—H4B120.0 (12)N4—C14—C15120.93 (13)
H4A—N4—H4B115.7 (17)N4—C14—C13121.64 (13)
C4—C5—C6119.22 (14)C15—C14—C13117.42 (13)
C4—C5—H5121.8 (10)C16—C15—C14121.21 (13)
C6—C5—H5118.9 (10)C16—C15—H15120.8 (10)
C7—C6—C5120.70 (15)C14—C15—H15118.0 (10)
C7—C6—H6120.2 (11)C15—C16—C17120.71 (13)
C5—C6—H6119.1 (11)C15—C16—H16120.0 (11)
C8—C7—C6119.64 (14)C17—C16—H16119.3 (11)
C8—C7—H7119.9 (11)C18—C17—C16119.10 (14)
C6—C7—H7120.5 (11)C18—C17—H17117.6 (10)
C7—C8—C9120.70 (14)C16—C17—H17123.2 (10)
C7—C8—H8121.8 (11)C17—C18—C13120.32 (13)
C9—C8—H8117.5 (11)C17—C18—H18120.3 (9)
C8—C9—C4119.05 (14)C13—C18—H18119.4 (9)
C3—N1—N2—C11.13 (14)C6—C7—C8—C92.4 (3)
C4—N1—N2—C1178.18 (11)C7—C8—C9—C40.1 (2)
N1—N2—C1—C20.78 (14)C5—C4—C9—C83.0 (2)
N1—N2—C1—C10178.48 (12)N1—C4—C9—C8177.95 (13)
N2—C1—C2—C12178.39 (13)C13—N3—C12—C2172.18 (12)
C10—C1—C2—C120.7 (2)C13—N3—C12—C118.6 (2)
N2—C1—C2—C30.19 (14)C1—C2—C12—N3179.71 (13)
C10—C1—C2—C3178.94 (14)C3—C2—C12—N31.77 (18)
N2—N1—C3—O1178.75 (12)C1—C2—C12—C111.1 (2)
C4—N1—C3—O12.0 (2)C3—C2—C12—C11179.04 (12)
N2—N1—C3—C20.99 (14)C12—N3—C13—C1858.78 (19)
C4—N1—C3—C2178.23 (12)C12—N3—C13—C14127.44 (14)
C12—C2—C3—O12.3 (2)C18—C13—C14—N4179.68 (13)
C1—C2—C3—O1179.25 (13)N3—C13—C14—N46.59 (19)
C12—C2—C3—N1177.93 (11)C18—C13—C14—C150.54 (19)
C1—C2—C3—N10.48 (13)N3—C13—C14—C15174.28 (12)
C3—N1—C4—C521.3 (2)N4—C14—C15—C16179.20 (13)
N2—N1—C4—C5157.89 (12)C13—C14—C15—C160.1 (2)
C3—N1—C4—C9159.63 (13)C14—C15—C16—C170.2 (2)
N2—N1—C4—C921.19 (17)C15—C16—C17—C180.8 (2)
C9—C4—C5—C63.4 (2)C16—C17—C18—C131.3 (2)
N1—C4—C5—C6177.52 (13)C14—C13—C18—C171.2 (2)
C4—C5—C6—C71.0 (2)N3—C13—C18—C17174.77 (13)
C5—C6—C7—C81.9 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O10.955 (18)1.863 (18)2.6965 (14)144.3 (15)
N4—H4A···N2i0.92 (2)2.47 (2)3.2542 (17)144.1 (16)
N4—H4B···O1ii0.93 (2)2.14 (2)3.0090 (16)153.3 (17)
C9—H9···N4i1.008 (17)2.567 (17)3.571 (2)173.7 (13)
C11—H11C···N1iii0.98 (2)2.68 (2)3.5669 (19)152.0 (16)
C18—H18···N2iii0.997 (17)2.439 (17)3.3984 (18)161.2 (13)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1, z+1; (iii) x+1, y+2, z+1.
 

Acknowledgements

The support of NSF–MRI Grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.

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