3,4-Bis(4-meth­oxy­phen­yl)-2,5-dihydro-1H-pyrrole-2,5-dione

Huang, L.; Li, Y.; Gao, D.; Du, Z.

doi:10.1107/S1600536812014158

organic compounds

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ISSN: 2056-9890

Volume 68| Part 5| May 2012| Page o1328

doi:10.1107/S1600536812014158

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3,4-Bis(4-methoxyphenyl)-2,5-dihydro-1H-pyrrole-2,5-dione

Liangzhu Huang,^a Youqiang Li,^a Dongmei Gao ^a and Zhenting Du ^a ^*

^aCollege of Science, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
^*Correspondence e-mail: duzt@nwsuaf.edu.cn

(Received 29 March 2012; accepted 1 April 2012; online 6 April 2012)

In the title compound, C₁₈H₁₅NO₄, the benzene rings form quite different dihedral angles [16.07 (1) and 59.50 (1)°] with the central pyrrole ring, indicating a twisted molecule. Conjugation is indicated between the five- and six-membered rings by the lengths of the C—C bonds which link them [1.462 (3) and 1.477 (3) Å]. The most prominent feature of the crystal packing is the formation of inversion dimers via eight-membered {⋯HNCO}₂ synthons.

Related literature

For the use of 3,4-diaryl-substituted maleic imide derivatives as photochromic materials, see: Irie (2000 ); Liu et al. (2003 ). For the synthesis, see: Faul et al. (1999 ).

Experimental

Crystal data

C₁₈H₁₅NO₄
M_r = 309.31
Triclinic, $[P \overline 1]$
a = 6.030 (3) Å
b = 8.971 (5) Å
c = 14.023 (8) Å
α = 90.945 (6)°
β = 95.205 (5)°
γ = 97.862 (5)°
V = 748.0 (7) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 296 K
0.69 × 0.23 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.233, T_max = 0.982
3943 measured reflections
2607 independent reflections
1751 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.051
wR(F²) = 0.148
S = 1.03
2607 reflections
211 parameters
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.86	2.03	2.882 (3)	168
Symmetry code: (i) -x, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812014158/tk5079sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812014158/tk5079Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812014158/tk5079Isup3.cdx

Supporting information file. DOI: 10.1107/S1600536812014158/tk5079Isup4.cml

checkCIF report

Comment top

3,4-Diaryl substituted maleic imide is a conjugated unit which has interesting optical and electronic properties. A number of 3,4-diaryl substituted maleic imide derivatives have been designed and synthesized to be used as photo-chromic materials (Irie, 2000; Liu et al., 2003). In the course of exploring new photo-chromic compounds, we obtained an intermediate compound, 3,4-bis(4'-methoxyphenyl)maleic imide, (I). Herein, we report its structure.

The molecule was designed to feature two terminal methoxy group to enhance its solubility and to, later, enable fictionalization. The inter-planar angles between the two benzene rings connected with the maleic imide five-membered ring are different. The inter-planar angle between the benzene plane defined by C5–C10 and maleic imide plane is 16.07 (1) °. However, the inter-planar angle between the other benzene plane defined by C12–C17 and maleic imide plane is 59.50 (1) °. The lengths of the two single bonds connecting benzene groups and maleic imide are respectively 1.462 (3) Å (C2—C5) and 1.477 (3) Å (C3—C12), which are obviously shorter than typical Csp³—Csp³ single bond. This means that the bonding between the six-membered ring and the five-membered ring is quite conjugated.

Related literature top

For the use of 3,4-diaryl-substituted maleic imide derivatives as photochromic materials, see: Irie (2000); Liu et al. (2003). For the synthesis, see: Faul et al. (1999).

Experimental top

For synthesis of imide (I), an improved procedure (Faul et al., 1999) was followed using 4-methoxyphenylethylglyoxalate (2.1 g, 10 mmol), 4-methoxyphenylacetamide (1.65 g, 10 mmol) and freshly prepared NaOEt (40 mmol) in absolute ethanol (20 ml). The mixture was refluxed for 4 h and poured into diluted HCl. After conventional workup, purification was achieved by column chromatography (ethyl acetate/hexanes 1:1) to yield (I) (2.0 g, 65%) as a yellow solid. Crystals of (I) precipitated at 298 K from its methanol solution by slow evaporation.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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

Fig. 1. The molecular structure of (I). Displacement ellipsoids are drawn at the 30% probability level.

3,4-Bis(4-methoxyphenyl)-2,5-dihydro-1H-pyrrole-2,5-dione top

Crystal data top

C₁₈H₁₅NO₄	Z = 2
M_r = 309.31	F(000) = 324
Triclinic, P1	D_x = 1.373 Mg m⁻³
Hall symbol: -P 1	Melting point: 517 K
a = 6.030 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.971 (5) Å	Cell parameters from 1101 reflections
c = 14.023 (8) Å	θ = 2.7–23.6°
α = 90.945 (6)°	µ = 0.10 mm⁻¹
β = 95.205 (5)°	T = 296 K
γ = 97.862 (5)°	Block, yellow
V = 748.0 (7) Å³	0.69 × 0.23 × 0.19 mm

Data collection top

Bruker APEXII CCD diffractometer	2607 independent reflections
Radiation source: fine-focus sealed tube	1751 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ϕ and ω scans	θ_max = 25.2°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −7→7
T_min = 0.233, T_max = 0.982	k = −10→8
3943 measured reflections	l = −16→16

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)] = 0.051	H-atom parameters constrained
wR(F²) = 0.148	w = 1/[σ²(F_o²) + (0.0769P)²] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
2607 reflections	Δρ_max = 0.16 e Å⁻³
211 parameters	Δρ_min = −0.18 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: 0.114 (12)

Crystal data top

C₁₈H₁₅NO₄	γ = 97.862 (5)°
M_r = 309.31	V = 748.0 (7) Å³
Triclinic, P1	Z = 2
a = 6.030 (3) Å	Mo Kα radiation
b = 8.971 (5) Å	µ = 0.10 mm⁻¹
c = 14.023 (8) Å	T = 296 K
α = 90.945 (6)°	0.69 × 0.23 × 0.19 mm
β = 95.205 (5)°

Data collection top

Bruker APEXII CCD diffractometer	2607 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	1751 reflections with I > 2σ(I)
T_min = 0.233, T_max = 0.982	R_int = 0.034
3943 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.051	0 restraints
wR(F²) = 0.148	H-atom parameters constrained
S = 1.03	Δρ_max = 0.16 e Å⁻³
2607 reflections	Δρ_min = −0.18 e Å⁻³
211 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
C1	0.3834 (4)	0.3007 (3)	0.96603 (16)	0.0422 (6)
C2	0.4781 (4)	0.3299 (2)	0.87029 (14)	0.0359 (6)
C3	0.3710 (4)	0.4394 (2)	0.82907 (15)	0.0351 (5)
C4	0.2055 (4)	0.4800 (3)	0.89376 (15)	0.0385 (6)
C5	0.6460 (4)	0.2446 (2)	0.83558 (15)	0.0374 (6)
C6	0.6830 (4)	0.2411 (3)	0.73879 (16)	0.0453 (6)
H6	0.6022	0.2964	0.6961	0.054*
C7	0.8349 (4)	0.1582 (3)	0.70524 (16)	0.0504 (7)
H7	0.8558	0.1583	0.6403	0.060*
C8	0.9589 (4)	0.0736 (2)	0.76676 (16)	0.0427 (6)
C9	0.9229 (4)	0.0735 (3)	0.86255 (17)	0.0497 (7)
H9	1.0021	0.0164	0.9047	0.060*
C10	0.7698 (4)	0.1579 (3)	0.89605 (16)	0.0462 (6)
H10	0.7486	0.1571	0.9609	0.055*
C11	1.2389 (5)	−0.0910 (3)	0.7865 (2)	0.0646 (8)
H11A	1.3177	−0.0288	0.8385	0.097*
H11B	1.3454	−0.1313	0.7500	0.097*
H11C	1.1421	−0.1721	0.8114	0.097*
C12	0.4059 (4)	0.5231 (2)	0.74060 (14)	0.0347 (5)
C13	0.6128 (4)	0.6031 (3)	0.72713 (16)	0.0449 (6)
H13	0.7322	0.6006	0.7737	0.054*
C14	0.6481 (4)	0.6866 (3)	0.64669 (16)	0.0465 (6)
H14	0.7886	0.7405	0.6399	0.056*
C15	0.4738 (4)	0.6893 (3)	0.57684 (16)	0.0441 (6)
C16	0.2652 (4)	0.6106 (3)	0.58874 (17)	0.0537 (7)
H16	0.1469	0.6125	0.5416	0.064*
C17	0.2309 (4)	0.5294 (3)	0.66974 (16)	0.0458 (6)
H17	0.0889	0.4782	0.6772	0.055*
C18	0.6974 (5)	0.8516 (4)	0.4787 (2)	0.0779 (9)
H18A	0.7448	0.9232	0.5307	0.117*
H18B	0.6827	0.9037	0.4198	0.117*
H18C	0.8070	0.7840	0.4750	0.117*
N1	0.2275 (3)	0.3981 (2)	0.97460 (12)	0.0434 (5)
H1	0.1543	0.4062	1.0239	0.052*
O1	0.0729 (3)	0.57097 (18)	0.88000 (11)	0.0482 (5)
O2	0.4269 (3)	0.2105 (2)	1.02547 (12)	0.0629 (6)
O3	1.1072 (3)	−0.00307 (19)	0.72612 (12)	0.0586 (5)
O4	0.4878 (3)	0.7688 (2)	0.49458 (12)	0.0668 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0439 (14)	0.0460 (14)	0.0379 (13)	0.0089 (12)	0.0043 (11)	0.0091 (11)
C2	0.0362 (13)	0.0366 (12)	0.0347 (12)	0.0050 (10)	0.0019 (10)	0.0052 (10)
C3	0.0356 (13)	0.0361 (12)	0.0340 (12)	0.0072 (10)	0.0024 (10)	0.0059 (9)
C4	0.0360 (13)	0.0406 (13)	0.0399 (13)	0.0072 (11)	0.0052 (10)	0.0066 (10)
C5	0.0385 (13)	0.0367 (12)	0.0380 (12)	0.0077 (11)	0.0041 (10)	0.0076 (10)
C6	0.0568 (16)	0.0453 (14)	0.0373 (13)	0.0193 (12)	0.0045 (11)	0.0088 (11)
C7	0.0687 (18)	0.0513 (15)	0.0371 (13)	0.0240 (14)	0.0124 (12)	0.0089 (11)
C8	0.0464 (15)	0.0342 (12)	0.0499 (14)	0.0103 (11)	0.0101 (11)	0.0052 (11)
C9	0.0565 (17)	0.0496 (15)	0.0465 (14)	0.0182 (13)	0.0045 (12)	0.0147 (12)
C10	0.0524 (15)	0.0535 (15)	0.0373 (13)	0.0196 (13)	0.0084 (11)	0.0111 (11)
C11	0.071 (2)	0.0505 (16)	0.081 (2)	0.0338 (15)	0.0144 (16)	0.0137 (14)
C12	0.0351 (13)	0.0382 (13)	0.0331 (11)	0.0121 (10)	0.0041 (10)	0.0071 (9)
C13	0.0369 (14)	0.0571 (15)	0.0410 (13)	0.0097 (12)	−0.0013 (11)	0.0134 (11)
C14	0.0400 (14)	0.0529 (15)	0.0466 (14)	0.0039 (12)	0.0062 (11)	0.0142 (12)
C15	0.0542 (16)	0.0460 (14)	0.0346 (12)	0.0132 (12)	0.0062 (11)	0.0115 (10)
C16	0.0490 (16)	0.0707 (18)	0.0397 (14)	0.0086 (14)	−0.0083 (12)	0.0152 (12)
C17	0.0390 (14)	0.0530 (15)	0.0436 (14)	0.0015 (12)	−0.0001 (11)	0.0105 (11)
C18	0.090 (2)	0.079 (2)	0.0653 (19)	0.0022 (19)	0.0234 (17)	0.0333 (16)
N1	0.0472 (12)	0.0525 (12)	0.0352 (10)	0.0163 (10)	0.0135 (9)	0.0107 (9)
O1	0.0461 (10)	0.0555 (10)	0.0485 (10)	0.0206 (9)	0.0112 (8)	0.0133 (8)
O2	0.0737 (13)	0.0724 (13)	0.0524 (10)	0.0323 (11)	0.0196 (9)	0.0322 (10)
O3	0.0685 (12)	0.0565 (11)	0.0605 (11)	0.0324 (10)	0.0198 (9)	0.0118 (9)
O4	0.0743 (14)	0.0783 (13)	0.0479 (11)	0.0073 (11)	0.0062 (10)	0.0328 (10)

Geometric parameters (Å, º) top

C1—O2	1.208 (2)	C11—O3	1.429 (3)
C1—N1	1.380 (3)	C11—H11A	0.9600
C1—C2	1.519 (3)	C11—H11B	0.9600
C2—C3	1.357 (3)	C11—H11C	0.9600
C2—C5	1.462 (3)	C12—C13	1.382 (3)
C3—C12	1.477 (3)	C12—C17	1.390 (3)
C3—C4	1.485 (3)	C13—C14	1.381 (3)
C4—O1	1.224 (3)	C13—H13	0.9300
C4—N1	1.367 (3)	C14—C15	1.373 (3)
C5—C10	1.395 (3)	C14—H14	0.9300
C5—C6	1.396 (3)	C15—O4	1.369 (3)
C6—C7	1.366 (3)	C15—C16	1.381 (3)
C6—H6	0.9300	C16—C17	1.375 (3)
C7—C8	1.393 (3)	C16—H16	0.9300
C7—H7	0.9300	C17—H17	0.9300
C8—O3	1.358 (3)	C18—O4	1.413 (3)
C8—C9	1.380 (3)	C18—H18A	0.9600
C9—C10	1.380 (3)	C18—H18B	0.9600
C9—H9	0.9300	C18—H18C	0.9600
C10—H10	0.9300	N1—H1	0.8600

O2—C1—N1	124.0 (2)	O3—C11—H11C	109.5
O2—C1—C2	129.2 (2)	H11A—C11—H11C	109.5
N1—C1—C2	106.80 (19)	H11B—C11—H11C	109.5
C3—C2—C5	131.08 (19)	C13—C12—C17	117.5 (2)
C3—C2—C1	106.54 (19)	C13—C12—C3	120.88 (19)
C5—C2—C1	122.34 (19)	C17—C12—C3	121.5 (2)
C2—C3—C12	131.28 (19)	C14—C13—C12	122.1 (2)
C2—C3—C4	108.34 (18)	C14—C13—H13	118.9
C12—C3—C4	120.22 (18)	C12—C13—H13	118.9
O1—C4—N1	124.7 (2)	C15—C14—C13	119.4 (2)
O1—C4—C3	127.6 (2)	C15—C14—H14	120.3
N1—C4—C3	107.73 (19)	C13—C14—H14	120.3
C10—C5—C6	116.7 (2)	O4—C15—C14	124.7 (2)
C10—C5—C2	122.1 (2)	O4—C15—C16	115.7 (2)
C6—C5—C2	121.1 (2)	C14—C15—C16	119.6 (2)
C7—C6—C5	121.6 (2)	C17—C16—C15	120.6 (2)
C7—C6—H6	119.2	C17—C16—H16	119.7
C5—C6—H6	119.2	C15—C16—H16	119.7
C6—C7—C8	121.0 (2)	C16—C17—C12	120.8 (2)
C6—C7—H7	119.5	C16—C17—H17	119.6
C8—C7—H7	119.5	C12—C17—H17	119.6
O3—C8—C9	125.3 (2)	O4—C18—H18A	109.5
O3—C8—C7	116.1 (2)	O4—C18—H18B	109.5
C9—C8—C7	118.5 (2)	H18A—C18—H18B	109.5
C8—C9—C10	120.2 (2)	O4—C18—H18C	109.5
C8—C9—H9	119.9	H18A—C18—H18C	109.5
C10—C9—H9	119.9	H18B—C18—H18C	109.5
C9—C10—C5	122.0 (2)	C4—N1—C1	110.48 (18)
C9—C10—H10	119.0	C4—N1—H1	124.8
C5—C10—H10	119.0	C1—N1—H1	124.8
O3—C11—H11A	109.5	C8—O3—C11	118.18 (19)
O3—C11—H11B	109.5	C15—O4—C18	118.1 (2)
H11A—C11—H11B	109.5

O2—C1—C2—C3	178.3 (2)	C6—C5—C10—C9	0.5 (3)
N1—C1—C2—C3	−0.8 (2)	C2—C5—C10—C9	177.8 (2)
O2—C1—C2—C5	0.4 (4)	C2—C3—C12—C13	−56.6 (3)
N1—C1—C2—C5	−178.69 (19)	C4—C3—C12—C13	118.2 (2)
C5—C2—C3—C12	−8.5 (4)	C2—C3—C12—C17	126.1 (3)
C1—C2—C3—C12	173.9 (2)	C4—C3—C12—C17	−59.2 (3)
C5—C2—C3—C4	176.3 (2)	C17—C12—C13—C14	−0.2 (3)
C1—C2—C3—C4	−1.4 (2)	C3—C12—C13—C14	−177.7 (2)
C2—C3—C4—O1	−177.7 (2)	C12—C13—C14—C15	−0.9 (4)
C12—C3—C4—O1	6.5 (3)	C13—C14—C15—O4	179.4 (2)
C2—C3—C4—N1	3.1 (2)	C13—C14—C15—C16	1.0 (4)
C12—C3—C4—N1	−172.74 (19)	O4—C15—C16—C17	−178.6 (2)
C3—C2—C5—C10	166.7 (2)	C14—C15—C16—C17	−0.1 (4)
C1—C2—C5—C10	−16.0 (3)	C15—C16—C17—C12	−1.0 (4)
C3—C2—C5—C6	−16.1 (4)	C13—C12—C17—C16	1.1 (4)
C1—C2—C5—C6	161.3 (2)	C3—C12—C17—C16	178.6 (2)
C10—C5—C6—C7	−0.7 (4)	O1—C4—N1—C1	177.1 (2)
C2—C5—C6—C7	−178.1 (2)	C3—C4—N1—C1	−3.6 (3)
C5—C6—C7—C8	0.1 (4)	O2—C1—N1—C4	−176.4 (2)
C6—C7—C8—O3	−179.2 (2)	C2—C1—N1—C4	2.8 (2)
C6—C7—C8—C9	0.9 (4)	C9—C8—O3—C11	−0.3 (3)
O3—C8—C9—C10	179.0 (2)	C7—C8—O3—C11	179.8 (2)
C7—C8—C9—C10	−1.1 (4)	C14—C15—O4—C18	1.5 (4)
C8—C9—C10—C5	0.4 (4)	C16—C15—O4—C18	179.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.86	2.03	2.882 (3)	168

Symmetry code: (i) −x, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₅NO₄
M_r	309.31
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	6.030 (3), 8.971 (5), 14.023 (8)
α, β, γ (°)	90.945 (6), 95.205 (5), 97.862 (5)
V (Å³)	748.0 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.69 × 0.23 × 0.19

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.233, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	3943, 2607, 1751
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.148, 1.03
No. of reflections	2607
No. of parameters	211
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.18

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.86	2.03	2.882 (3)	168

Symmetry code: (i) −x, −y+1, −z+2.

Acknowledgements

Financial support from the Program for Excellent Young Talents in Northwest A&F University (No. 2111020712) and the opening project of the Xinjiang Production Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin (BRTD1004) is greatly appreciated.

References

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