Diethyl 3,3′-(phenyl­methyl­ene)bis­(1H-indole-2-carboxyl­ate)

Sun, H.-S.; Li, Y.-L.; Xu, N.; Xu, H.; Zhang, J.-D.

doi:10.1107/S1600536812036239

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2764

doi:10.1107/S1600536812036239

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Diethyl 3,3′-(phenylmethylene)bis(1H-indole-2-carboxylate)

Hong-Shun Sun,^a ^* Yu-Long Li,^a Ning Xu,^a Hong Xu ^a and Ji-Dong Zhang ^a

^aChemical Engineering Department, Nanjing College of Chemical Technology, Nanjing 210048, People's Republic of China
^*Correspondence e-mail: njutshs@126.com

(Received 18 August 2012; accepted 19 August 2012; online 25 August 2012)

In the title compound, C₂₉H₂₆N₂O₄, the benzene ring is twisted by 73.5 (5) and 84.9 (3)° with respect to the mean planes of the two indole ring systems; the mean planes of the indole ring systems are oriented at a dihedral angle of 82.0 (5)°. In the crystal, molecules are linked by pairs of N—H⋯O hydrogen bonds into chains.

Related literature

For applications of indole derivatives, see: Poter et al. (1977 ); Sundberg (1996 ); Chang et al. (1999 ); Ge et al. (1999 ); Ni (2008 ).

Experimental

Crystal data

C₂₉H₂₆N₂O₄
M_r = 466.52
Triclinic, $[P \overline 1]$
a = 8.7340 (17) Å
b = 9.871 (2) Å
c = 15.000 (3) Å
α = 76.14 (3)°
β = 83.91 (3)°
γ = 83.09 (3)°
V = 1242.4 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.30 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
4879 measured reflections
4557 independent reflections
2813 reflections with I > 2σ(I)
R_int = 0.032
3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.144
S = 1.00
4557 reflections
316 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O2ⁱ	0.86	2.21	2.955 (3)	144
N2—H2A⋯O4ⁱⁱ	0.86	2.07	2.880 (3)	157
Symmetry codes: (i) -x, -y+2, -z+1; (ii) -x+1, -y+1, -z+2.

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812036239/xu5612sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812036239/xu5612Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812036239/xu5612Isup3.cml

checkCIF report

Comment top

Indole derivatives are found abundantly in a variety of natural plants and exhibit various physiological properties (Poter et al., 1977; Sundberg, 1996). Among them, bis-indolymethane derivatives are found to be kinds of potentially bioactive compounds (Chang et al., 1999; Ge et al., 1999). In recent years, the synthesis and application of bis-indolymethane derivatives have been widely studied. The title compound is one of bis-indolymethane derivatives as a precursor for MRI Contrast Agents (Ni, 2008). We report here its crystal structure.

The molecular structure of the title compound is shown in Fig. 1. The benzene ring is twisted to the two indole rings with the dihedral angles of 73.5 (5) and 84.9 (3)°, respectively. Two indole rings make a dihedral angle of 82.0 (5)° to each other.

As shown in Figure 2, the molecules are linked by paired N—H···O hydrogen bonds into dimers in the crystal lattice. The structural parameters for the intermolecular hydrogen bonds resulting in the formation of dimers are given in Table 1.

Related literature top

For applications of indole derivatives, see: Poter et al. (1977); Sundberg (1996); Chang et al. (1999); Ge et al. (1999); Ni (2008).

Experimental top

Ethyl indole-2-carboxylate (18.9 g, 100 mmol) was dissolved in 200 ml ethanol; commercially available benzaldehyde (5.3 g, 50 mmol) was added and the mixture was heated to reflux temperature. Concentrated HCl (3.7 ml) was added and the reaction was left for 1 h. After cooling the white product was filtered off and washed thoroughly with ethanol. The reaction can be followed by TLC (CHCl₃:hexane = 1:1). Yield was 90%. Crystals of the title compound suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Figure 1. The molecular structure of (I), showing the atom-numbering scheme and displacement ellipsoids at the 30% probability level.

Figure 2. A packing diagram of (I). Intermolecular hydrogen bonds are shown as dashed lines.

Diethyl 3,3'-(phenylmethylene)bis(1H-indole-2-carboxylate) top

Crystal data top

C₂₉H₂₆N₂O₄	Z = 2
M_r = 466.52	F(000) = 492
Triclinic, P1	D_x = 1.247 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.7340 (17) Å	Cell parameters from 25 reflections
b = 9.871 (2) Å	θ = 9–13°
c = 15.000 (3) Å	µ = 0.08 mm⁻¹
α = 76.14 (3)°	T = 293 K
β = 83.91 (3)°	Block, colorless
γ = 83.09 (3)°	0.30 × 0.20 × 0.10 mm
V = 1242.4 (4) Å³

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.032
Radiation source: fine-focus sealed tube	θ_max = 25.4°, θ_min = 1.4°
Graphite monochromator	h = 0→10
ω/2θ scans	k = −11→11
4879 measured reflections	l = −17→18
4557 independent reflections	3 standard reflections every 200 reflections
2813 reflections with I > 2σ(I)	intensity decay: 1%

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.144	H-atom parameters constrained
S = 1.00	w = 1/[σ²(F_o²) + (0.068P)²] where P = (F_o² + 2F_c²)/3
4557 reflections	(Δ/σ)_max < 0.001
316 parameters	Δρ_max = 0.33 e Å⁻³
2 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₂₉H₂₆N₂O₄	γ = 83.09 (3)°
M_r = 466.52	V = 1242.4 (4) Å³
Triclinic, P1	Z = 2
a = 8.7340 (17) Å	Mo Kα radiation
b = 9.871 (2) Å	µ = 0.08 mm⁻¹
c = 15.000 (3) Å	T = 293 K
α = 76.14 (3)°	0.30 × 0.20 × 0.10 mm
β = 83.91 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.032
4879 measured reflections	3 standard reflections every 200 reflections
4557 independent reflections	intensity decay: 1%
2813 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.059	2 restraints
wR(F²) = 0.144	H-atom parameters constrained
S = 1.00	Δρ_max = 0.33 e Å⁻³
4557 reflections	Δρ_min = −0.24 e Å⁻³
316 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
N1	0.1091 (2)	1.1102 (2)	0.57403 (13)	0.0464 (5)
H1A	0.0562	1.1030	0.5305	0.056*
O1	0.3652 (2)	0.79594 (18)	0.61548 (14)	0.0671 (6)
C1	0.0036 (3)	1.3484 (3)	0.59245 (18)	0.0543 (7)
H1B	−0.0653	1.3654	0.5469	0.065*
N2	0.3177 (2)	0.6564 (2)	0.93548 (13)	0.0455 (5)
H2A	0.3453	0.5760	0.9700	0.055*
O2	0.1783 (2)	0.8636 (2)	0.51907 (13)	0.0684 (6)
C2	0.0155 (3)	1.4450 (3)	0.64135 (19)	0.0622 (8)
H2B	−0.0449	1.5305	0.6283	0.075*
O3	0.65528 (18)	0.75379 (17)	0.78745 (11)	0.0501 (5)
C3	0.1166 (3)	1.4189 (3)	0.71086 (19)	0.0617 (8)
H3A	0.1214	1.4872	0.7435	0.074*
O4	0.6289 (2)	0.57275 (18)	0.90776 (13)	0.0650 (6)
C4	0.2091 (3)	1.2949 (3)	0.73230 (18)	0.0556 (7)
H4A	0.2753	1.2789	0.7791	0.067*
C5	0.2020 (3)	1.1927 (2)	0.68248 (15)	0.0408 (6)
C6	0.0979 (3)	1.2226 (3)	0.61280 (16)	0.0451 (6)
C7	0.2770 (3)	1.0539 (2)	0.68458 (15)	0.0384 (6)
C8	0.2186 (3)	1.0099 (2)	0.61581 (15)	0.0402 (6)
C9	0.2502 (3)	0.8841 (3)	0.57918 (18)	0.0491 (6)
C10	0.4101 (4)	0.6726 (3)	0.5781 (3)	0.0934 (12)
H10A	0.3348	0.6054	0.6016	0.112*
H10B	0.4081	0.6996	0.5116	0.112*
C11	0.5551 (5)	0.6089 (5)	0.5996 (4)	0.1460 (19)
H11A	0.5781	0.5285	0.5733	0.219*
H11B	0.5575	0.5800	0.6653	0.219*
H11C	0.6308	0.6740	0.5752	0.219*
C12	0.3962 (3)	0.9705 (2)	0.74867 (15)	0.0373 (6)
H12A	0.4708	0.9217	0.7106	0.045*
C13	0.4886 (3)	1.0644 (2)	0.78505 (16)	0.0395 (6)
C14	0.6008 (3)	1.1351 (3)	0.72766 (19)	0.0568 (7)
H14A	0.6244	1.1202	0.6686	0.068*
C15	0.6790 (4)	1.2282 (3)	0.7569 (3)	0.0764 (9)
H15A	0.7541	1.2759	0.7170	0.092*
C16	0.6473 (4)	1.2511 (3)	0.8438 (2)	0.0710 (9)
H16A	0.6991	1.3154	0.8624	0.085*
C17	0.5397 (3)	1.1794 (3)	0.9029 (2)	0.0611 (8)
H17A	0.5190	1.1934	0.9623	0.073*
C18	0.4605 (3)	1.0849 (3)	0.87424 (17)	0.0478 (6)
H18A	0.3882	1.0350	0.9151	0.057*
C19	0.3294 (3)	0.8562 (2)	0.82476 (15)	0.0374 (6)
C20	0.1766 (3)	0.8539 (2)	0.87173 (15)	0.0395 (6)
C21	0.0399 (3)	0.9474 (3)	0.86615 (18)	0.0511 (7)
H21A	0.0363	1.0322	0.8226	0.061*
C22	−0.0862 (3)	0.9119 (3)	0.92517 (19)	0.0619 (8)
H22A	−0.1757	0.9738	0.9214	0.074*
C23	−0.0847 (3)	0.7852 (3)	0.9912 (2)	0.0632 (8)
H23A	−0.1734	0.7642	1.0298	0.076*
C24	0.0448 (3)	0.6912 (3)	1.00012 (17)	0.0527 (7)
H24A	0.0464	0.6071	1.0443	0.063*
C25	0.1743 (3)	0.7277 (2)	0.93981 (16)	0.0426 (6)
C26	0.4107 (3)	0.7330 (2)	0.86766 (15)	0.0388 (6)
C27	0.5734 (3)	0.6772 (2)	0.85723 (16)	0.0402 (6)
C28	0.8177 (3)	0.7041 (3)	0.77442 (18)	0.0553 (7)
H28A	0.8282	0.6102	0.7638	0.066*
H28B	0.8701	0.7019	0.8287	0.066*
C29	0.8863 (3)	0.8028 (3)	0.6932 (2)	0.0802 (10)
H29A	0.9940	0.7727	0.6825	0.120*
H29B	0.8759	0.8952	0.7048	0.120*
H29C	0.8335	0.8044	0.6400	0.120*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0488 (13)	0.0511 (13)	0.0378 (11)	0.0003 (10)	−0.0143 (10)	−0.0049 (10)
O1	0.0723 (14)	0.0525 (12)	0.0859 (14)	0.0166 (10)	−0.0364 (11)	−0.0322 (10)
C1	0.0510 (16)	0.0538 (17)	0.0462 (15)	0.0093 (13)	−0.0099 (13)	0.0071 (13)
N2	0.0469 (13)	0.0359 (11)	0.0461 (12)	0.0014 (10)	−0.0069 (10)	0.0039 (9)
O2	0.0705 (13)	0.0795 (14)	0.0662 (13)	0.0077 (11)	−0.0280 (11)	−0.0355 (11)
C2	0.067 (2)	0.0520 (17)	0.0555 (18)	0.0173 (15)	−0.0037 (15)	−0.0005 (15)
O3	0.0440 (10)	0.0501 (10)	0.0468 (10)	0.0059 (8)	−0.0009 (8)	0.0007 (8)
C3	0.076 (2)	0.0451 (16)	0.0604 (18)	0.0116 (15)	−0.0099 (16)	−0.0114 (13)
O4	0.0580 (12)	0.0507 (11)	0.0675 (12)	0.0134 (9)	−0.0037 (10)	0.0132 (10)
C4	0.0693 (19)	0.0456 (16)	0.0508 (16)	0.0055 (14)	−0.0184 (14)	−0.0086 (13)
C5	0.0446 (14)	0.0399 (14)	0.0320 (13)	0.0002 (11)	−0.0026 (11)	0.0008 (11)
C6	0.0468 (15)	0.0456 (15)	0.0356 (14)	−0.0011 (12)	−0.0037 (11)	0.0032 (11)
C7	0.0397 (13)	0.0400 (13)	0.0317 (12)	0.0015 (11)	−0.0049 (11)	−0.0030 (10)
C8	0.0442 (14)	0.0384 (13)	0.0361 (13)	0.0003 (11)	−0.0100 (11)	−0.0040 (11)
C9	0.0489 (16)	0.0536 (16)	0.0442 (15)	−0.0016 (13)	−0.0104 (13)	−0.0088 (13)
C10	0.098 (3)	0.060 (2)	0.138 (3)	0.0167 (19)	−0.046 (2)	−0.050 (2)
C11	0.123 (4)	0.135 (4)	0.200 (5)	0.021 (3)	−0.042 (4)	−0.082 (4)
C12	0.0407 (14)	0.0348 (13)	0.0353 (13)	0.0057 (11)	−0.0102 (11)	−0.0073 (10)
C13	0.0398 (14)	0.0362 (13)	0.0390 (14)	0.0037 (11)	−0.0102 (11)	−0.0026 (11)
C14	0.0574 (17)	0.0537 (17)	0.0561 (17)	−0.0123 (14)	0.0014 (14)	−0.0055 (14)
C15	0.069 (2)	0.0589 (19)	0.097 (3)	−0.0266 (17)	0.0001 (19)	−0.0023 (18)
C16	0.074 (2)	0.0601 (19)	0.085 (2)	−0.0156 (17)	−0.0234 (19)	−0.0172 (18)
C17	0.074 (2)	0.0598 (18)	0.0549 (17)	−0.0035 (16)	−0.0240 (16)	−0.0178 (15)
C18	0.0524 (16)	0.0494 (15)	0.0412 (15)	−0.0021 (13)	−0.0084 (12)	−0.0090 (12)
C19	0.0405 (14)	0.0338 (13)	0.0363 (13)	0.0004 (11)	−0.0105 (11)	−0.0036 (10)
C20	0.0413 (14)	0.0376 (13)	0.0379 (13)	−0.0032 (11)	−0.0069 (11)	−0.0042 (10)
C21	0.0479 (16)	0.0469 (15)	0.0527 (16)	0.0056 (13)	−0.0080 (13)	−0.0034 (12)
C22	0.0407 (16)	0.0669 (19)	0.070 (2)	0.0074 (14)	0.0033 (15)	−0.0103 (16)
C23	0.0467 (17)	0.071 (2)	0.0633 (19)	−0.0068 (15)	0.0103 (14)	−0.0054 (16)
C24	0.0485 (16)	0.0557 (17)	0.0483 (16)	−0.0087 (14)	−0.0017 (13)	−0.0004 (13)
C25	0.0413 (14)	0.0420 (14)	0.0442 (14)	−0.0024 (12)	−0.0085 (12)	−0.0080 (11)
C26	0.0444 (14)	0.0343 (13)	0.0343 (13)	0.0017 (11)	−0.0066 (11)	−0.0023 (10)
C27	0.0447 (15)	0.0333 (13)	0.0382 (13)	0.0012 (11)	−0.0054 (12)	−0.0014 (11)
C28	0.0501 (17)	0.0554 (17)	0.0543 (17)	0.0047 (13)	0.0025 (13)	−0.0084 (13)
C29	0.065 (2)	0.082 (2)	0.088 (2)	−0.0115 (18)	0.0150 (18)	−0.0142 (19)

Geometric parameters (Å, º) top

N1—C6	1.361 (3)	C12—C13	1.524 (3)
N1—C8	1.375 (3)	C12—H12A	0.9800
N1—H1A	0.8600	C13—C14	1.374 (3)
O1—C9	1.320 (3)	C13—C18	1.392 (3)
O1—C10	1.455 (3)	C14—C15	1.382 (4)
C1—C2	1.354 (4)	C14—H14A	0.9300
C1—C6	1.393 (3)	C15—C16	1.370 (4)
C1—H1B	0.9300	C15—H15A	0.9300
N2—C25	1.364 (3)	C16—C17	1.362 (4)
N2—C26	1.368 (3)	C16—H16A	0.9300
N2—H2A	0.8600	C17—C18	1.394 (3)
O2—C9	1.219 (3)	C17—H17A	0.9300
C2—C3	1.394 (4)	C18—H18A	0.9300
C2—H2B	0.9300	C19—C26	1.382 (3)
O3—C27	1.331 (3)	C19—C20	1.442 (3)
O3—C28	1.453 (3)	C20—C25	1.410 (3)
C3—C4	1.372 (3)	C20—C21	1.415 (3)
C3—H3A	0.9300	C21—C22	1.363 (3)
O4—C27	1.207 (3)	C21—H21A	0.9300
C4—C5	1.402 (3)	C22—C23	1.397 (4)
C4—H4A	0.9300	C22—H22A	0.9300
C5—C6	1.413 (3)	C23—C24	1.371 (4)
C5—C7	1.440 (3)	C23—H23A	0.9300
C7—C8	1.375 (3)	C24—C25	1.397 (3)
C7—C12	1.520 (3)	C24—H24A	0.9300
C8—C9	1.460 (3)	C26—C27	1.467 (3)
C10—C11	1.379 (4)	C28—C29	1.486 (4)
C10—H10A	0.9700	C28—H28A	0.9700
C10—H10B	0.9700	C28—H28B	0.9700
C11—H11A	0.9600	C29—H29A	0.9600
C11—H11B	0.9600	C29—H29B	0.9600
C11—H11C	0.9600	C29—H29C	0.9600
C12—C19	1.522 (3)

C6—N1—C8	108.91 (19)	C18—C13—C12	122.3 (2)
C6—N1—H1A	125.5	C13—C14—C15	120.6 (3)
C8—N1—H1A	125.5	C13—C14—H14A	119.7
C9—O1—C10	117.3 (2)	C15—C14—H14A	119.7
C2—C1—C6	117.7 (3)	C16—C15—C14	120.8 (3)
C2—C1—H1B	121.2	C16—C15—H15A	119.6
C6—C1—H1B	121.2	C14—C15—H15A	119.6
C25—N2—C26	109.28 (19)	C17—C16—C15	119.7 (3)
C25—N2—H2A	125.4	C17—C16—H16A	120.2
C26—N2—H2A	125.4	C15—C16—H16A	120.2
C1—C2—C3	121.4 (3)	C16—C17—C18	120.0 (3)
C1—C2—H2B	119.3	C16—C17—H17A	120.0
C3—C2—H2B	119.3	C18—C17—H17A	120.0
C27—O3—C28	116.10 (19)	C13—C18—C17	120.6 (3)
C4—C3—C2	121.6 (3)	C13—C18—H18A	119.7
C4—C3—H3A	119.2	C17—C18—H18A	119.7
C2—C3—H3A	119.2	C26—C19—C20	105.12 (19)
C3—C4—C5	119.0 (2)	C26—C19—C12	125.5 (2)
C3—C4—H4A	120.5	C20—C19—C12	129.27 (19)
C5—C4—H4A	120.5	C25—C20—C21	117.3 (2)
C4—C5—C6	117.8 (2)	C25—C20—C19	107.5 (2)
C4—C5—C7	135.3 (2)	C21—C20—C19	135.2 (2)
C6—C5—C7	106.9 (2)	C22—C21—C20	119.4 (2)
N1—C6—C1	129.3 (2)	C22—C21—H21A	120.3
N1—C6—C5	108.1 (2)	C20—C21—H21A	120.3
C1—C6—C5	122.6 (2)	C21—C22—C23	121.8 (3)
C8—C7—C5	105.8 (2)	C21—C22—H22A	119.1
C8—C7—C12	126.1 (2)	C23—C22—H22A	119.1
C5—C7—C12	128.1 (2)	C24—C23—C22	121.3 (3)
N1—C8—C7	110.2 (2)	C24—C23—H23A	119.3
N1—C8—C9	116.0 (2)	C22—C23—H23A	119.3
C7—C8—C9	133.8 (2)	C23—C24—C25	116.9 (2)
O2—C9—O1	122.9 (3)	C23—C24—H24A	121.5
O2—C9—C8	122.9 (2)	C25—C24—H24A	121.5
O1—C9—C8	114.2 (2)	N2—C25—C24	129.0 (2)
C11—C10—O1	113.3 (3)	N2—C25—C20	107.6 (2)
C11—C10—H10A	108.9	C24—C25—C20	123.3 (2)
O1—C10—H10A	108.9	N2—C26—C19	110.4 (2)
C11—C10—H10B	108.9	N2—C26—C27	117.0 (2)
O1—C10—H10B	108.9	C19—C26—C27	132.5 (2)
H10A—C10—H10B	107.7	O4—C27—O3	122.8 (2)
C10—C11—H11A	109.5	O4—C27—C26	123.4 (2)
C10—C11—H11B	109.5	O3—C27—C26	113.7 (2)
H11A—C11—H11B	109.5	O3—C28—C29	107.3 (2)
C10—C11—H11C	109.5	O3—C28—H28A	110.2
H11A—C11—H11C	109.5	C29—C28—H28A	110.2
H11B—C11—H11C	109.5	O3—C28—H28B	110.2
C7—C12—C19	113.36 (18)	C29—C28—H28B	110.2
C7—C12—C13	112.51 (18)	H28A—C28—H28B	108.5
C19—C12—C13	112.78 (18)	C28—C29—H29A	109.5
C7—C12—H12A	105.8	C28—C29—H29B	109.5
C19—C12—H12A	105.8	H29A—C29—H29B	109.5
C13—C12—H12A	105.8	C28—C29—H29C	109.5
C14—C13—C18	118.2 (2)	H29A—C29—H29C	109.5
C14—C13—C12	119.4 (2)	H29B—C29—H29C	109.5

C6—C1—C2—C3	−1.2 (4)	C13—C14—C15—C16	0.5 (5)
C1—C2—C3—C4	0.5 (4)	C14—C15—C16—C17	1.3 (5)
C2—C3—C4—C5	0.4 (4)	C15—C16—C17—C18	−1.1 (4)
C3—C4—C5—C6	−0.6 (4)	C14—C13—C18—C17	2.8 (4)
C3—C4—C5—C7	−179.5 (3)	C12—C13—C18—C17	−175.3 (2)
C8—N1—C6—C1	179.6 (2)	C16—C17—C18—C13	−1.0 (4)
C8—N1—C6—C5	−0.8 (3)	C7—C12—C19—C26	152.1 (2)
C2—C1—C6—N1	−179.6 (2)	C13—C12—C19—C26	−78.6 (3)
C2—C1—C6—C5	0.9 (4)	C7—C12—C19—C20	−32.3 (3)
C4—C5—C6—N1	−179.6 (2)	C13—C12—C19—C20	97.0 (3)
C7—C5—C6—N1	−0.5 (3)	C26—C19—C20—C25	−0.8 (2)
C4—C5—C6—C1	0.0 (4)	C12—C19—C20—C25	−177.0 (2)
C7—C5—C6—C1	179.1 (2)	C26—C19—C20—C21	176.8 (3)
C4—C5—C7—C8	−179.5 (3)	C12—C19—C20—C21	0.5 (4)
C6—C5—C7—C8	1.6 (2)	C25—C20—C21—C22	−0.5 (4)
C4—C5—C7—C12	0.6 (4)	C19—C20—C21—C22	−177.8 (3)
C6—C5—C7—C12	−178.3 (2)	C20—C21—C22—C23	−0.2 (4)
C6—N1—C8—C7	1.9 (3)	C21—C22—C23—C24	0.7 (5)
C6—N1—C8—C9	−177.3 (2)	C22—C23—C24—C25	−0.5 (4)
C5—C7—C8—N1	−2.2 (3)	C26—N2—C25—C24	−178.0 (2)
C12—C7—C8—N1	177.8 (2)	C26—N2—C25—C20	0.3 (3)
C5—C7—C8—C9	176.9 (3)	C23—C24—C25—N2	177.9 (2)
C12—C7—C8—C9	−3.2 (4)	C23—C24—C25—C20	−0.2 (4)
C10—O1—C9—O2	2.7 (4)	C21—C20—C25—N2	−177.8 (2)
C10—O1—C9—C8	−176.1 (2)	C19—C20—C25—N2	0.3 (3)
N1—C8—C9—O2	−4.4 (4)	C21—C20—C25—C24	0.7 (4)
C7—C8—C9—O2	176.7 (3)	C19—C20—C25—C24	178.7 (2)
N1—C8—C9—O1	174.4 (2)	C25—N2—C26—C19	−0.8 (3)
C7—C8—C9—O1	−4.6 (4)	C25—N2—C26—C27	175.8 (2)
C9—O1—C10—C11	162.2 (4)	C20—C19—C26—N2	1.0 (3)
C8—C7—C12—C19	−76.6 (3)	C12—C19—C26—N2	177.4 (2)
C5—C7—C12—C19	103.4 (3)	C20—C19—C26—C27	−175.0 (2)
C8—C7—C12—C13	154.0 (2)	C12—C19—C26—C27	1.5 (4)
C5—C7—C12—C13	−26.1 (3)	C28—O3—C27—O4	0.4 (3)
C7—C12—C13—C14	−74.5 (3)	C28—O3—C27—C26	179.4 (2)
C19—C12—C13—C14	155.7 (2)	N2—C26—C27—O4	−3.8 (4)
C7—C12—C13—C18	103.5 (2)	C19—C26—C27—O4	171.9 (3)
C19—C12—C13—C18	−26.2 (3)	N2—C26—C27—O3	177.19 (19)
C18—C13—C14—C15	−2.5 (4)	C19—C26—C27—O3	−7.1 (4)
C12—C13—C14—C15	175.6 (2)	C27—O3—C28—C29	179.4 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O2ⁱ	0.86	2.21	2.955 (3)	144
N2—H2A···O4ⁱⁱ	0.86	2.07	2.880 (3)	157

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

Experimental details

Crystal data
Chemical formula	C₂₉H₂₆N₂O₄
M_r	466.52
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	8.7340 (17), 9.871 (2), 15.000 (3)
α, β, γ (°)	76.14 (3), 83.91 (3), 83.09 (3)
V (Å³)	1242.4 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.30 × 0.20 × 0.10

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	4879, 4557, 2813
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.059, 0.144, 1.00
No. of reflections	4557
No. of parameters	316
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.33, −0.24

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O2ⁱ	0.86	2.21	2.955 (3)	144
N2—H2A···O4ⁱⁱ	0.86	2.07	2.880 (3)	157

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

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for assistance with the data collection.

References

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