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Acta Cryst. (2009). E65, o24    [ doi:10.1107/S1600536808039214 ]

N-(3-Bromo-1,4-dioxo-1,4-dihydro-2-naphthyl)-2-chloro-N-(2-chlorobenzoyl)benzamide

E. S. Akinboye, R. J. Butcher, Y. Brandy, T. A. Adesiyun and O. Bakare

Abstract top

The title compound, C24H12BrCl2NO4, was synthesized from 2-amino-3-bromo-1,4-naphthoquinone and 2-chlorobenzoyl chloride. The crystal structure shows that each of the chlorophenyl rings is inclined at about 60° to the naphthoquinone ring system. The two chlorophenyl rings adopt a conformation that ensures that chlorine substituents are anti so as to reduce electronic repulsion. An examination of the packing shows close O...Br and Cl...Cl contacts of 2.947 (2) and 3.346 (1) Å, respectively. In addition, the molecules are linked by weak intermolecular C-H...O and C-H...Cl interactions.

Comment top

Certain compounds with the chloro-1,4-naphthoquinone skeleton were reported to exhibit antineoplastic property and some have inhibitory effects on human cytomegalovirus (HCMV) protease (Chang et al., 1999; Ertl et al., 1999). The amido and imido derivatives of 3-chloro-1,4-naphthoquinone have been reported to exhibit appreciable anti-inflammatory, antiplatelet, antiallergic and anticancer activities (Lien et al., 1997; Huang et al., 1998; Bakare et al., 2003; Copeland et al.,2007) We have developed some imido-substituted 2-chloro-1,4-naphthoquinones with cytotoxic activities on some prostate cancer cell lines. In continuation of our work, the title compound (I) was synthesized as a potential anticancer agent.

Each of the phenyl groups is inclined at about 60° to the naphthoquinone ring of the titled compound C24H12BrCl2NO4. The two chlorophenyl rings adopt a conformation that ensures that chlorine substituents are anti to each other so as to reduce electronic repulsion. An examination of the packing shows close contacts between O1A and Br at (1/2 - x, 1/2 + y, 3/2 - z) (2.947 (2) Å) and Cl1A and Cl1B at (x, 1 + y, z) (3.346 (1) Å). The explanation of these close contacts lies in a balance between the torsion angles subtended at the N which balances short intramolecular contacts against short intermolecular contacts and comes up with the best compromise.

Related literature top

For similar structures, see: Lien et al. (1997); Huang et al. (1998); Bakare et al. (2003); Copeland et al. (2007); Win et al. (2005); Rubin-Preminger et al. (2004). For the properties of compounds with the chloro-1,4-naphthoquinone skeleton, see: Chang et al. (1999); Ertl et al. (1999).

Experimental top

To a solution of 2-amino-3-bromo-1,4-naphthoquinone (300 mg, 1.21 mmol) in dry THF was added NaH (72.6 mg 3.025 mmol) and the mixture was stirred for 15 minutes. 2-Chloro-benzoylchloride (0.37 ml) was added thereafter and this mixture was stirred at room temperature for 16–24 hr under argon. The solvent was removed in vacuo and the solid residue was dissolved in dichloromethane (40 ml). The resultant solution was washed with water (3 x 15 ml), saturated NaCl solution (2 x 15 ml) and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo and the residue triturated in ethyl acetate to give a yellow solid (280.0 g m). This was recrystallized in ethyl acetate to furnish the title imide (214.2 mg, 34%).

Refinement top

All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms with C—H distances of 0.95 Å and Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2007); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of (I) showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 20% probability level.
[Figure 2] Fig. 2. View of the packing viewed down the a axis. Dashed bonds show weak C—H···O interactions and close Cl···Cl contacts.
N-(3-Bromo-1,4-dioxo-1,4-dihydro-2-naphthyl)-2-chloro-N-(2- chlorobenzoyl)benzamide top
Crystal data top
C24H12BrCl2NO4F(000) = 1056
Mr = 529.16Dx = 1.660 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 12.8590 (3) ÅCell parameters from 6385 reflections
b = 7.8126 (1) Åθ = 4.5–34.8°
c = 21.9574 (4) ŵ = 2.23 mm−1
β = 106.272 (2)°T = 200 K
V = 2117.53 (7) Å3Needle, pale yellow
Z = 40.46 × 0.18 × 0.15 mm
Data collection top
Oxford Diffraction Gemini R
diffractometer		8407 independent reflections
Radiation source: fine-focus sealed tube4388 reflections with I > 2σ(I)
graphiteRint = 0.041
Detector resolution: 10.5081 pixels mm-1θmax = 34.8°, θmin = 4.5°
φ and ω scansh = −19→20
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)		k = −12→12
Tmin = 0.945, Tmax = 1.000l = −34→28
27164 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.123H-atom parameters constrained
S = 0.92 w = 1/[σ2(Fo2) + (0.0618P)2]
where P = (Fo2 + 2Fc2)/3
8407 reflections(Δ/σ)max = 0.003
289 parametersΔρmax = 2.03 e Å−3
0 restraintsΔρmin = −0.70 e Å−3
Crystal data top
C24H12BrCl2NO4V = 2117.53 (7) Å3
Mr = 529.16Z = 4
Monoclinic, P21/nMo Kα radiation
a = 12.8590 (3) ŵ = 2.23 mm−1
b = 7.8126 (1) ÅT = 200 K
c = 21.9574 (4) Å0.46 × 0.18 × 0.15 mm
β = 106.272 (2)°
Data collection top
Oxford Diffraction Gemini R
diffractometer		8407 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)		4388 reflections with I > 2σ(I)
Tmin = 0.945, Tmax = 1.000Rint = 0.041
27164 measured reflectionsθmax = 34.8°
Refinement top
R[F2 > 2σ(F2)] = 0.047H-atom parameters constrained
wR(F2) = 0.123Δρmax = 2.03 e Å−3
S = 0.92Δρmin = −0.70 e Å−3
8407 reflectionsAbsolute structure: ?
289 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
Br0.16560 (2)0.07777 (4)0.693146 (11)0.03453 (9)
Cl1A0.54339 (7)0.57382 (8)0.71533 (4)0.04354 (18)
Cl1B0.56864 (7)−0.14656 (8)0.60493 (4)0.04445 (19)
O1−0.05313 (17)0.1335 (4)0.60398 (10)0.0601 (7)
O20.24523 (15)0.3427 (3)0.49462 (8)0.0406 (5)
O1A0.31064 (15)0.4218 (2)0.68149 (8)0.0325 (4)
O1B0.33990 (16)−0.0028 (2)0.54700 (9)0.0389 (5)
N0.32004 (15)0.2100 (2)0.61270 (8)0.0207 (4)
C10.20724 (18)0.2157 (3)0.58269 (10)0.0207 (4)
C20.1317 (2)0.1653 (3)0.61071 (10)0.0251 (5)
C30.0139 (2)0.1748 (3)0.57732 (11)0.0298 (5)
C4−0.01873 (19)0.2343 (3)0.51068 (10)0.0239 (5)
C5−0.1271 (2)0.2365 (3)0.47668 (11)0.0290 (5)
H5A−0.18030.19630.49570.035*
C6−0.1578 (2)0.2969 (3)0.41533 (12)0.0342 (6)
H6A−0.23230.29960.39250.041*
C7−0.0814 (2)0.3536 (4)0.38673 (12)0.0367 (6)
H7A−0.10370.39550.34440.044*
C80.0275 (2)0.3495 (3)0.41937 (11)0.0333 (6)
H8A0.08000.38730.39940.040*
C90.0601 (2)0.2897 (3)0.48187 (10)0.0237 (5)
C100.1758 (2)0.2874 (3)0.51699 (10)0.0252 (5)
C1A0.36326 (19)0.3069 (3)0.66818 (10)0.0211 (4)
C2A0.47008 (19)0.2488 (3)0.71062 (10)0.0235 (5)
C3A0.5541 (2)0.3614 (3)0.73579 (11)0.0292 (5)
C4A0.6516 (2)0.3043 (4)0.77548 (12)0.0405 (7)
H4AA0.70950.38230.79140.049*
C5A0.6642 (3)0.1328 (4)0.79186 (13)0.0454 (7)
H5AA0.73090.09330.81920.054*
C6A0.5810 (3)0.0197 (4)0.76886 (12)0.0404 (7)
H6AA0.5896−0.09740.78090.048*
C7A0.4848 (2)0.0758 (3)0.72825 (11)0.0298 (5)
H7AA0.4277−0.00350.71200.036*
C1B0.38232 (19)0.1143 (3)0.57957 (11)0.0235 (5)
C2B0.49383 (19)0.1791 (3)0.58353 (10)0.0228 (5)
C3B0.5818 (2)0.0694 (3)0.59230 (11)0.0260 (5)
C4B0.6829 (2)0.1307 (3)0.59320 (12)0.0319 (6)
H4BA0.74320.05520.60070.038*
C5B0.6956 (2)0.3040 (3)0.58300 (12)0.0323 (6)
H5BA0.76480.34700.58320.039*
C6B0.6095 (2)0.4132 (3)0.57274 (12)0.0307 (5)
H6BA0.61860.53080.56460.037*
C7B0.5094 (2)0.3529 (3)0.57424 (10)0.0252 (5)
H7BA0.45050.43040.56890.030*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br0.02744 (14)0.05392 (17)0.02277 (12)−0.00532 (12)0.00791 (9)0.01052 (11)
Cl1A0.0473 (5)0.0356 (3)0.0481 (4)−0.0096 (3)0.0140 (3)−0.0032 (3)
Cl1B0.0482 (5)0.0279 (3)0.0601 (5)0.0041 (3)0.0198 (4)0.0029 (3)
O10.0209 (11)0.120 (2)0.0407 (12)−0.0055 (12)0.0117 (9)0.0258 (13)
O20.0219 (10)0.0688 (12)0.0316 (10)−0.0072 (9)0.0084 (8)0.0174 (9)
O1A0.0269 (10)0.0382 (9)0.0299 (9)0.0062 (8)0.0040 (7)−0.0080 (8)
O1B0.0308 (11)0.0415 (10)0.0461 (11)−0.0133 (9)0.0134 (8)−0.0235 (9)
N0.0144 (9)0.0301 (9)0.0175 (8)−0.0022 (8)0.0044 (7)−0.0041 (7)
C10.0158 (11)0.0288 (11)0.0170 (10)−0.0020 (9)0.0040 (8)−0.0006 (9)
C20.0196 (12)0.0373 (13)0.0190 (10)−0.0022 (10)0.0061 (9)0.0007 (9)
C30.0178 (12)0.0454 (14)0.0279 (12)−0.0019 (11)0.0090 (10)0.0050 (11)
C40.0178 (12)0.0308 (12)0.0222 (11)−0.0022 (10)0.0043 (8)−0.0022 (9)
C50.0175 (12)0.0344 (13)0.0341 (13)−0.0033 (10)0.0056 (10)−0.0015 (11)
C60.0199 (13)0.0412 (14)0.0349 (13)0.0011 (11)−0.0033 (10)−0.0042 (12)
C70.0324 (16)0.0460 (15)0.0258 (12)0.0015 (13)−0.0016 (11)0.0050 (11)
C80.0289 (15)0.0462 (14)0.0242 (12)−0.0028 (12)0.0065 (10)0.0057 (11)
C90.0216 (12)0.0282 (11)0.0195 (10)−0.0017 (10)0.0028 (8)0.0004 (9)
C100.0209 (12)0.0329 (12)0.0217 (10)−0.0036 (10)0.0062 (9)0.0003 (9)
C1A0.0212 (12)0.0238 (10)0.0179 (10)−0.0029 (9)0.0047 (8)0.0008 (8)
C2A0.0197 (12)0.0345 (12)0.0163 (9)−0.0008 (10)0.0051 (8)−0.0021 (9)
C3A0.0252 (13)0.0389 (13)0.0235 (11)−0.0071 (11)0.0068 (10)−0.0034 (10)
C4A0.0286 (15)0.0624 (18)0.0266 (13)−0.0115 (14)0.0009 (11)−0.0042 (13)
C5A0.0344 (17)0.0663 (19)0.0318 (14)0.0121 (15)0.0031 (12)0.0050 (14)
C6A0.049 (2)0.0436 (15)0.0270 (13)0.0128 (14)0.0079 (12)0.0035 (12)
C7A0.0329 (14)0.0333 (12)0.0222 (11)0.0048 (11)0.0058 (9)−0.0010 (10)
C1B0.0189 (12)0.0303 (12)0.0221 (10)0.0003 (9)0.0070 (9)−0.0014 (9)
C2B0.0200 (12)0.0318 (12)0.0165 (9)0.0000 (10)0.0051 (8)−0.0029 (9)
C3B0.0265 (13)0.0287 (11)0.0251 (11)0.0048 (11)0.0111 (9)0.0001 (10)
C4B0.0249 (14)0.0430 (14)0.0290 (12)0.0044 (11)0.0094 (10)0.0000 (11)
C5B0.0241 (14)0.0441 (14)0.0313 (13)−0.0098 (12)0.0119 (10)−0.0066 (11)
C6B0.0326 (14)0.0322 (12)0.0309 (12)−0.0063 (12)0.0148 (10)−0.0015 (11)
C7B0.0201 (12)0.0349 (12)0.0221 (11)−0.0026 (10)0.0083 (9)−0.0004 (10)
Geometric parameters (Å, °) top
Br—C21.869 (2)C1A—C2A1.498 (3)
Cl1A—C3A1.715 (3)C2A—C3A1.383 (3)
Cl1B—C3B1.726 (2)C2A—C7A1.404 (3)
O1—C31.214 (3)C3A—C4A1.384 (4)
O2—C101.213 (3)C4A—C5A1.385 (4)
O1A—C1A1.209 (3)C4A—H4AA0.9500
O1B—C1B1.195 (3)C5A—C6A1.370 (5)
N—C1A1.410 (3)C5A—H5AA0.9500
N—C11.416 (3)C6A—C7A1.378 (4)
N—C1B1.434 (3)C6A—H6AA0.9500
C1—C21.346 (3)C7A—H7AA0.9500
C1—C101.494 (3)C1B—C2B1.500 (3)
C2—C31.489 (3)C2B—C3B1.389 (3)
C3—C41.479 (3)C2B—C7B1.396 (3)
C4—C51.384 (3)C3B—C4B1.381 (4)
C4—C91.405 (3)C4B—C5B1.390 (4)
C5—C61.377 (3)C4B—H4BA0.9500
C5—H5A0.9500C5B—C6B1.365 (4)
C6—C71.378 (4)C5B—H5BA0.9500
C6—H6A0.9500C6B—C7B1.380 (4)
C7—C81.383 (4)C6B—H6BA0.9500
C7—H7A0.9500C7B—H7BA0.9500
C8—C91.398 (3)H6AA—Cl1Ai2.923
C8—H8A0.9500H6BA—Cl1Bii2.805
C9—C101.471 (3)
C1A—N—C1119.32 (18)C7A—C2A—C1A119.5 (2)
C1A—N—C1B125.28 (19)C2A—C3A—C4A121.0 (3)
C1—N—C1B115.17 (17)C2A—C3A—Cl1A120.9 (2)
C2—C1—N123.7 (2)C4A—C3A—Cl1A118.0 (2)
C2—C1—C10121.1 (2)C3A—C4A—C5A119.6 (3)
N—C1—C10115.22 (18)C3A—C4A—H4AA120.2
C1—C2—C3121.7 (2)C5A—C4A—H4AA120.2
C1—C2—Br123.22 (18)C6A—C5A—C4A120.4 (3)
C3—C2—Br115.11 (16)C6A—C5A—H5AA119.8
O1—C3—C4121.2 (2)C4A—C5A—H5AA119.8
O1—C3—C2120.8 (2)C5A—C6A—C7A120.0 (3)
C4—C3—C2118.1 (2)C5A—C6A—H6AA120.0
C5—C4—C9119.8 (2)C7A—C6A—H6AA120.0
C5—C4—C3120.1 (2)C6A—C7A—C2A120.8 (3)
C9—C4—C3120.1 (2)C6A—C7A—H7AA119.6
C6—C5—C4120.1 (2)C2A—C7A—H7AA119.6
C6—C5—H5A120.0O1B—C1B—N118.5 (2)
C4—C5—H5A120.0O1B—C1B—C2B124.2 (2)
C5—C6—C7120.7 (2)N—C1B—C2B117.08 (19)
C5—C6—H6A119.7C3B—C2B—C7B118.4 (2)
C7—C6—H6A119.7C3B—C2B—C1B121.8 (2)
C6—C7—C8120.2 (2)C7B—C2B—C1B119.6 (2)
C6—C7—H7A119.9C4B—C3B—C2B121.0 (2)
C8—C7—H7A119.9C4B—C3B—Cl1B118.11 (19)
C7—C8—C9119.9 (2)C2B—C3B—Cl1B120.86 (19)
C7—C8—H8A120.1C3B—C4B—C5B119.2 (2)
C9—C8—H8A120.1C3B—C4B—H4BA120.4
C8—C9—C4119.3 (2)C5B—C4B—H4BA120.4
C8—C9—C10120.0 (2)C6B—C5B—C4B120.6 (2)
C4—C9—C10120.7 (2)C6B—C5B—H5BA119.7
O2—C10—C9122.3 (2)C4B—C5B—H5BA119.7
O2—C10—C1119.6 (2)C5B—C6B—C7B120.1 (2)
C9—C10—C1118.1 (2)C5B—C6B—H6BA119.9
O1A—C1A—N119.8 (2)C7B—C6B—H6BA119.9
O1A—C1A—C2A123.5 (2)C6B—C7B—C2B120.5 (2)
N—C1A—C2A116.47 (19)C6B—C7B—H7BA119.7
C3A—C2A—C7A118.2 (2)C2B—C7B—H7BA119.7
C3A—C2A—C1A122.3 (2)
C1A—N—C1—C2−61.2 (3)C1—N—C1A—C2A157.69 (19)
C1B—N—C1—C2124.0 (2)C1B—N—C1A—C2A−28.1 (3)
C1A—N—C1—C10117.1 (2)O1A—C1A—C2A—C3A−51.8 (3)
C1B—N—C1—C10−57.7 (3)N—C1A—C2A—C3A133.8 (2)
N—C1—C2—C3179.6 (2)O1A—C1A—C2A—C7A125.2 (2)
C10—C1—C2—C31.4 (4)N—C1A—C2A—C7A−49.3 (3)
N—C1—C2—Br−0.8 (3)C7A—C2A—C3A—C4A2.3 (4)
C10—C1—C2—Br−179.02 (17)C1A—C2A—C3A—C4A179.3 (2)
C1—C2—C3—O1−177.8 (3)C7A—C2A—C3A—Cl1A178.70 (18)
Br—C2—C3—O12.5 (4)C1A—C2A—C3A—Cl1A−4.3 (3)
C1—C2—C3—C42.8 (4)C2A—C3A—C4A—C5A−2.0 (4)
Br—C2—C3—C4−176.85 (17)Cl1A—C3A—C4A—C5A−178.5 (2)
O1—C3—C4—C5−2.9 (4)C3A—C4A—C5A—C6A0.2 (4)
C2—C3—C4—C5176.5 (2)C4A—C5A—C6A—C7A1.2 (4)
O1—C3—C4—C9176.8 (3)C5A—C6A—C7A—C2A−0.9 (4)
C2—C3—C4—C9−3.9 (4)C3A—C2A—C7A—C6A−0.9 (4)
C9—C4—C5—C6−1.7 (4)C1A—C2A—C7A—C6A−177.9 (2)
C3—C4—C5—C6177.9 (2)C1A—N—C1B—O1B156.2 (2)
C4—C5—C6—C70.9 (4)C1—N—C1B—O1B−29.3 (3)
C5—C6—C7—C80.3 (4)C1A—N—C1B—C2B−29.4 (3)
C6—C7—C8—C9−0.8 (4)C1—N—C1B—C2B145.08 (19)
C7—C8—C9—C40.0 (4)O1B—C1B—C2B—C3B−48.2 (3)
C7—C8—C9—C10−179.2 (2)N—C1B—C2B—C3B137.8 (2)
C5—C4—C9—C81.2 (4)O1B—C1B—C2B—C7B127.7 (3)
C3—C4—C9—C8−178.4 (2)N—C1B—C2B—C7B−46.3 (3)
C5—C4—C9—C10−179.6 (2)C7B—C2B—C3B—C4B1.4 (3)
C3—C4—C9—C100.8 (3)C1B—C2B—C3B—C4B177.3 (2)
C8—C9—C10—O23.2 (4)C7B—C2B—C3B—Cl1B179.26 (17)
C4—C9—C10—O2−176.0 (2)C1B—C2B—C3B—Cl1B−4.8 (3)
C8—C9—C10—C1−177.5 (2)C2B—C3B—C4B—C5B−2.2 (3)
C4—C9—C10—C13.3 (3)Cl1B—C3B—C4B—C5B179.85 (19)
C2—C1—C10—O2174.9 (2)C3B—C4B—C5B—C6B0.6 (4)
N—C1—C10—O2−3.4 (3)C4B—C5B—C6B—C7B1.9 (4)
C2—C1—C10—C9−4.4 (3)C5B—C6B—C7B—C2B−2.7 (4)
N—C1—C10—C9177.21 (19)C3B—C2B—C7B—C6B1.1 (3)
C1—N—C1A—O1A−17.0 (3)C1B—C2B—C7B—C6B−174.9 (2)
C1B—N—C1A—O1A157.3 (2)
Symmetry codes: (i) x, y−1, z; (ii) x, y+1, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C5—H5A···O1Biii0.952.513.209 (3)131
C4B—H4BA···O1iv0.952.673.335 (3)128
C6B—H6BA···O2v0.952.653.296 (3)126
Symmetry codes: (iii) −x, −y, −z+1; (iv) x+1, y, z; (v) −x+1, −y+1, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C5—H5A···O1Bi0.952.513.209 (3)131
C4B—H4BA···O1ii0.952.673.335 (3)128
C6B—H6BA···O2iii0.952.653.296 (3)126
Symmetry codes: (i) −x, −y, −z+1; (ii) x+1, y, z; (iii) −x+1, −y+1, −z+1.
Acknowledgements top

RJB acknowledges the NSF–MRI program (grant No. CHE-0619278) for funds to purchase the X-ray diffractometer.

references
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