Naphthalene-1,8-di­amine–2-(pyrimidin-2-yl)-1H-perimidine (2/1)

Cucciolito, M.E.; Panunzi, B.; Ruffo, F.; Tuzi, A.

doi:10.1107/S1600536813016796

organic compounds

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ISSN: 2056-9890

Volume 69| Part 7| July 2013| Pages o1133-o1134

https://doi.org/10.1107/S1600536813016796

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Naphthalene-1,8-diamine–2-(pyrimidin-2-yl)-1H-perimidine (2/1)

Maria Elena Cucciolito,^a Barbara Panunzi,^b Francesco Ruffo ^a and Angela Tuzi ^a ^*

^aDipartimento di Scienze Chimiche, Università degli Studi di Napoli 'Federico II', Complesso di Monte S. Angelo, Via Cinthia, 80126 Napoli, Italy, and ^bDipartimento di Agraria, Università degli Studi di Napoli 'Federico II', Via Università 100, 80055 Portici, Italy
^*Correspondence e-mail: angela.tuzi@unina.it

(Received 12 June 2013; accepted 17 June 2013; online 22 June 2013)

In the title adduct, C₁₅H₁₀N₄·2C₁₀H₁₀N₂, the pyrimidine ring is nearly co-planar with the heteroatomic perimidine ring, as indicated dihedral angle between their mean planes of 3.21 (11)°. The diaminonaphthalene molecules are slightly twisted [dihedral angles = 4.2 (2) and 3.0 (2)°] because of the steric encumbrance of NH₂ groups. The perimidine and diaminonaphthalene molecules are linked by N—H⋯N hydrogen bonds, forming an R⁴₄(12) graph-set motif across an inversion center. In the crystal, alternating layers of the perimidine and diaminonaphthalene molecules are formed along [100]. In the perimidine layer, molecules are π–π stacked along the c-axis direction with an interplane separation of approximately 3.4 Å.

Related literature

For the coordination properties of perimidines, see: Morita et al. (2003 ); Cucciolito et al. (2013 ). For structural data on perimidines, see: Foces-Foces et al. (1993 ); Llamas-Saiz et al. (1995 ); Filatova et al. (2000 ); Murata et al. (2006 ); Smellie et al. (2011 ). For structural data on naphthalene-1,8-diamine, see: Llamas-Saiz et al. (1991 ); Basaran et al. (1993 ); Batsanov et al. (2001 ). For N-rich aromatic heterocycles in organic electronics and photonics, see: Goswami et al. (2010 ); Carella et al. (2012 ); Centore et al. (2012 ). For a general survey of hydrogen bonding in crystals, see: Desiraju & Steiner (1999 ); Steiner (2002 ). For hydrogen-bonding patterns in nitrogen-containing heterocycles, see: Centore et al. (2013a ,b ).

Experimental

Crystal data

C₁₅H₁₀N₄·2C₁₀H₁₀N₂
M_r = 562.67
Monoclinic, P 2₁ /c
a = 17.083 (2) Å
b = 12.139 (3) Å
c = 13.597 (2) Å
β = 90.76 (1)°
V = 2819.4 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 173 K
0.50 × 0.45 × 0.10 mm

Data collection

Bruker–Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.960, T_max = 0.992
22722 measured reflections
5184 independent reflections
2799 reflections with I > 2σ(I)
R_int = 0.080

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.142
S = 1.06
5184 reflections
415 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.19 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⋯N2Aⁱ	0.86 (3)	2.30 (3)	3.077 (4)	151 (2)
N1A—H1C⋯N2ⁱⁱ	0.87 (3)	2.42 (3)	3.153 (4)	142 (3)
N2A—H2C⋯N2	0.92 (3)	2.27 (3)	3.092 (4)	149 (3)
N2A—H2D⋯N1A	0.87 (3)	2.27 (3)	2.753 (5)	115 (2)
N1B—H1F⋯N2B	0.98 (4)	2.12 (3)	2.710 (5)	117 (2)
Symmetry codes: (i) -x, -y, -z+1; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: COLLECT (Nonius, 1999 ); cell refinement: DIRAX/LSQ (Duisenberg et al., 2000 ); data reduction: EVALCCD (Duisenberg et al., 2003 ); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: WinGX (Farrugia, 2012).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536813016796/go2093sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813016796/go2093Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536813016796/go2093Isup3.cml

checkCIF report

Comment top

During the studies on the coordination ability of perimidines containing four donor atoms (Cucciolito et al., 2013) we obtained the neutral 2-(pyrimidin-2-yl)-1H-perimidine-naphthalene-1,8-diamine (1/2) cocrystal. In view of its N-rich aromatic character, pyrimidinylperimidine can have interest also in organic electronics and photonics (Carella et al., 2012; Centore et al., 2012; Murata et al., 2006; Goswami et al., 2010).

Few structural data are found in the literature on neutral perimidines having one amino and one imino N atom at the heterocyclic mojety (Filatova et al., 2000; Foces-Foces et al., 1993; Llamas-Saiz et al., 1995; Murata et al., 2006; Smellie et al., 2011). Moreover, very few structural data on the naphthalene-1,8-diamine (DAN) ring system are found in the literature (Batsanov et al., 2001; Llamas-Saiz et al., 1991; Basaran et al., 1993). In particular, the title compound is the second example of a perimidine bearing a pyrimidine ring at C11 with the two N atoms in ortho position (Morita et al., 2003). In the title compound, one 2-(pyrimidin-2-yl)-1H-perimidine (PIM) molecule and two naphthalene-1,8-diamine (DAN-A and DAN-B) molecules are contained in the asymmetric unit (Fig.1). The aminic nature of N1 in PIM is clearly proven by location of the NH hydrogen atom in difference Fourier maps. The geometry at N1 is planar, as demonstrated by the free refinement of the attached hydrogen atom. The pyrimidine ring is nearly coplanar with the perimidine ring with a dihedral angle between their mean planes of 3.21 (11)°. In DAN-A and DAN-B molecules the geometric parameters are very similar to literature data of pure DAN (Llamas-Saiz et al., 1991; Basaran et al.,1993) and of octafluoronaphthalene-naphthalene-1,8-diamine co-crystal (Batsanov et al., 2001). As usually found, the molecule adopts a slightly twisted conformation due to the steric encumbrance of the two adjacent NH₂ groups. The hydrogen atoms of NH₂ groups, located in difference Fourier maps, confirm that two different orientations are adopted by the amine groups, with inward hydrogen atoms forced into intramolecular contacts. It is not clear if such kind of contacts, associated to a steric strain of the DAN molecule, can be considered as weak intermolecular hydrogen bonds or as constrain-due interactions. However, the refined positions of NH₂ hydrogen atoms give a N–H···N geometry that falls in the range of weak hydrogen bonds [D(X···A) = 3.0–4.0 Å and θ(X–A···H) = 90–180° (Desiraju & Steiner, 1999)].

PIM and DAN-A molecules are involved in N–H···N hydrogen bonds (Fig.2) forming the R⁴₄(12) graph-set motif across an inversion center. The amine N1 atom acts as donor towards N2Aⁱ (i = -x,-y,1 - z) and imine N2 atom acts as bifurcated acceptor from N1A and from N2Aⁱⁱ (ii = x, 1/2 - y, z - 1/2).

The DAN-B molecules are not involved in classic intermolecular hydrogen bonds, but only in weak CH···π and NH···π interactions (Fig.3) (N1B—H1E··· Cg1(C5A—C10A)[x, 1 + y, z] = 0.98 (4), 3.15 (4) Å, 151 (3)°; N2B—H2F···Cg2(C1B—C5B,C10B)[1 - x, -1/2 + y, 3/2 - z] = 0.91 (4), 3.35 (4) Å, 162 (3)°;C6B—H6B···Cg3(C1—C5,C10)[-x, 1/2 + y,3/2 - z] = 0.95, 3.632 Å, 141.8°).

In the crystal packing (Fig. 4) layers of PIM molecules are alternate to double layers of DAN-A and DAN-B molecules along [1 0 0] direction. In the perimidine layer molecules are π···π stacked along c with interplanar separation of approximately 3.4 Å.

Related literature top

For the coordination properties of perimidines, see: Morita et al. (2003); Cucciolito et al. (2013). For structural data on perimidines, see: Foces-Foces et al. (1993); Llamas-Saiz et al. (1995); Filatova et al. (2000); Murata et al. (2006); Smellie et al. (2011). For structural data on naphthalene-1,8-diamine, see: Llamas-Saiz et al. (1991); Basaran et al. (1993); Batsanov et al. (2001). For N-rich aromatic heterocycles in organic electronics and photonics, see: Goswami et al. (2010); Carella et al. (2012); Centore et al. (2012). For a general survey of hydrogen bonding in crystals, see: Desiraju & Steiner (1999); Steiner (2002). For hydrogen-bonding patterns in nitrogen-containing heterocycles, see: Centore et al. (2013a,b).

Experimental top

2-(pyrimidin-2-yl)-1H-perimidine was obtained from naphthalene-1,8-diamine and pyrimidine-2-carbonitrile, details on the synthesis will be reported in a forthcoming work. Block-shaped crystals of title compound were obtained by evaporation of an ethyl acetate/cyclohexane solution containing 2-(pyrimidin-2-yl)-1H-perimidine and naphthalene-1,8-diamine.

Structure description top

For the coordination properties of perimidines, see: Morita et al. (2003); Cucciolito et al. (2013). For structural data on perimidines, see: Foces-Foces et al. (1993); Llamas-Saiz et al. (1995); Filatova et al. (2000); Murata et al. (2006); Smellie et al. (2011). For structural data on naphthalene-1,8-diamine, see: Llamas-Saiz et al. (1991); Basaran et al. (1993); Batsanov et al. (2001). For N-rich aromatic heterocycles in organic electronics and photonics, see: Goswami et al. (2010); Carella et al. (2012); Centore et al. (2012). For a general survey of hydrogen bonding in crystals, see: Desiraju & Steiner (1999); Steiner (2002). For hydrogen-bonding patterns in nitrogen-containing heterocycles, see: Centore et al. (2013a,b).

Computing details top

Data collection: COLLECT (Nonius, 1999); cell refinement: DIRAX/LSQ (Duisenberg et al., 2000); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top

	Fig. 1. ORTEP view of the title compound. Thermal ellipsoids are drawn at 30% probability level.
	Fig. 2. H-bonding pattern involving pyrimidinylperimidine (PIM) and naphthalene-1,8-diamine (DAN-A) molecules.
	Fig. 3. naphthalene-1,8-diamine (DAN-B) molecule involved in weak CH···π and NH···π interactions. Cg1: centroid(C5A—C10A)[x, 1 + y, z]; Cg2: centroid(C1B—C5B,C10B)[1 - x, -1/2 + y, 3/2 - z]; Cg3: centroid(C1—C5,C10)[-x, 1/2 + y, 3/2 - z].
	Fig. 4. Crystal packing viewed along b axis showing short distances in the π-π stacked PIM molecules. Hydrogen bonds involving PIM molecules are drawn as dashed lines.

Naphthalene-1,8-diamine–2-(pyrimidin-2-yl)-1H-perimidine (2/1) top

Crystal data top

C₁₅H₁₀N₄·2C₁₀H₁₀N₂	F(000) = 1184
M_r = 562.67	D_x = 1.326 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 126 reflections
a = 17.083 (2) Å	θ = 3.4–21.8°
b = 12.139 (3) Å	µ = 0.08 mm⁻¹
c = 13.597 (2) Å	T = 173 K
β = 90.76 (1)°	Block, orange
V = 2819.4 (9) Å³	0.50 × 0.45 × 0.10 mm
Z = 4

Data collection top

Bruker–Nonius KappaCCD diffractometer	5184 independent reflections
Radiation source: normal-focus sealed tube	2799 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.080
Detector resolution: 9 pixels mm^-1	θ_max = 25.4°, θ_min = 3.2°
CCD rotation images, thick slices scans	h = −20→20
Absorption correction: multi-scan (SADABS; Bruker, 2001)	k = −14→14
T_min = 0.960, T_max = 0.992	l = −16→16
22722 measured reflections

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)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.142	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ²(F_o²) + (0.0402P)² + 1.5806P] where P = (F_o² + 2F_c²)/3
5184 reflections	(Δ/σ)_max < 0.001
415 parameters	Δρ_max = 0.19 e Å⁻³
2 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

C₁₅H₁₀N₄·2C₁₀H₁₀N₂	V = 2819.4 (9) Å³
M_r = 562.67	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 17.083 (2) Å	µ = 0.08 mm⁻¹
b = 12.139 (3) Å	T = 173 K
c = 13.597 (2) Å	0.50 × 0.45 × 0.10 mm
β = 90.76 (1)°

Data collection top

Bruker–Nonius KappaCCD diffractometer	5184 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	2799 reflections with I > 2σ(I)
T_min = 0.960, T_max = 0.992	R_int = 0.080
22722 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	2 restraints
wR(F²) = 0.142	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.19 e Å⁻³
5184 reflections	Δρ_min = −0.18 e Å⁻³
415 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	−0.06299 (14)	0.0273 (2)	0.36212 (17)	0.0276 (6)
H1	−0.0848 (16)	−0.037 (2)	0.365 (2)	0.033*
N2	0.05732 (13)	0.12080 (19)	0.37659 (16)	0.0269 (6)
N3	0.13410 (14)	−0.0767 (2)	0.38241 (18)	0.0352 (6)
N4	0.00939 (14)	−0.16518 (19)	0.37372 (17)	0.0309 (6)
N1A	0.17020 (18)	0.3184 (3)	0.7032 (2)	0.0500 (9)
H1C	0.1574 (19)	0.358 (3)	0.753 (3)	0.060*
H1D	0.1615 (19)	0.244 (3)	0.7159 (19)	0.060*
N2A	0.16490 (15)	0.1606 (2)	0.5578 (2)	0.0400 (7)
H2C	0.1462 (18)	0.126 (3)	0.502 (2)	0.048*
H2D	0.1347 (18)	0.216 (3)	0.5700 (19)	0.048*
N1B	0.44606 (19)	0.9546 (3)	0.6366 (2)	0.0624 (10)
H1E	0.430 (2)	1.011 (3)	0.588 (3)	0.075*
H1F	0.4405 (19)	0.878 (3)	0.615 (2)	0.075*
N2B	0.48654 (19)	0.7540 (3)	0.7084 (3)	0.0634 (10)
H2E	0.5269 (19)	0.805 (3)	0.702 (3)	0.076*
H2F	0.509 (2)	0.686 (3)	0.709 (3)	0.076*
C1	−0.10821 (16)	0.1228 (2)	0.3582 (2)	0.0270 (7)
C2	−0.18822 (16)	0.1208 (3)	0.3468 (2)	0.0334 (7)
H2	−0.2158	0.0532	0.3403	0.040*
C3	−0.22799 (18)	0.2222 (3)	0.3449 (2)	0.0407 (8)
H3	−0.2833	0.2224	0.3367	0.049*
C4	−0.18985 (19)	0.3200 (3)	0.3547 (2)	0.0391 (8)
H4	−0.2190	0.3867	0.3543	0.047*
C5	−0.10814 (17)	0.3240 (2)	0.3652 (2)	0.0299 (7)
C6	−0.0637 (2)	0.4223 (2)	0.3748 (2)	0.0380 (8)
H6	−0.0895	0.4916	0.3748	0.046*
C7	0.0159 (2)	0.4181 (2)	0.3840 (2)	0.0392 (8)
H7	0.0444	0.4849	0.3906	0.047*
C8	0.05660 (18)	0.3185 (2)	0.3841 (2)	0.0343 (8)
H8	0.1121	0.3181	0.3898	0.041*
C9	0.01606 (17)	0.2209 (2)	0.3757 (2)	0.0266 (7)
C10	−0.06663 (16)	0.2226 (2)	0.36614 (19)	0.0256 (7)
C11	0.01603 (16)	0.0311 (2)	0.3711 (2)	0.0244 (7)
C12	0.05592 (16)	−0.0776 (2)	0.37559 (19)	0.0253 (7)
C13	0.16700 (19)	−0.1763 (3)	0.3871 (2)	0.0416 (8)
H13	0.2225	−0.1807	0.3915	0.050*
C14	0.12521 (19)	−0.2720 (3)	0.3860 (2)	0.0366 (8)
H14	0.1502	−0.3418	0.3899	0.044*
C15	0.04540 (19)	−0.2627 (2)	0.3789 (2)	0.0347 (8)
H15	0.0146	−0.3278	0.3776	0.042*
C1A	0.24650 (19)	0.3402 (3)	0.6713 (2)	0.0370 (8)
C2A	0.2866 (2)	0.4285 (3)	0.7099 (2)	0.0491 (10)
H2A	0.2626	0.4724	0.7588	0.059*
C3A	0.3619 (2)	0.4554 (3)	0.6791 (3)	0.0533 (10)
H3A	0.3874	0.5183	0.7058	0.064*
C4A	0.39903 (19)	0.3927 (3)	0.6114 (3)	0.0454 (9)
H4A	0.4507	0.4110	0.5921	0.054*
C5A	0.36083 (17)	0.3002 (2)	0.5698 (2)	0.0320 (7)
C6A	0.40047 (18)	0.2335 (3)	0.5023 (2)	0.0395 (8)
H6A	0.4532	0.2496	0.4864	0.047*
C7A	0.36393 (19)	0.1463 (3)	0.4595 (2)	0.0419 (9)
H7A	0.3919	0.1002	0.4157	0.050*
C8A	0.28593 (18)	0.1239 (3)	0.4792 (2)	0.0374 (8)
H8A	0.2610	0.0635	0.4472	0.045*
C9A	0.24415 (16)	0.1870 (2)	0.5438 (2)	0.0293 (7)
C10A	0.28182 (16)	0.2759 (2)	0.5957 (2)	0.0285 (7)
C1B	0.40270 (18)	0.9666 (3)	0.7235 (3)	0.0426 (9)
C2B	0.3652 (2)	1.0638 (3)	0.7392 (3)	0.0549 (10)
H2B	0.3690	1.1203	0.6912	0.066*
C3B	0.3216 (2)	1.0833 (3)	0.8226 (3)	0.0632 (12)
H3B	0.2972	1.1529	0.8315	0.076*
C4B	0.3137 (2)	1.0033 (3)	0.8918 (3)	0.0563 (11)
H4B	0.2829	1.0162	0.9482	0.068*
C5B	0.35172 (18)	0.9003 (3)	0.8793 (3)	0.0409 (9)
C6B	0.3421 (2)	0.8162 (4)	0.9495 (3)	0.0567 (10)
H6B	0.3122	0.8297	1.0067	0.068*
C7B	0.3754 (2)	0.7156 (3)	0.9355 (3)	0.0601 (11)
H7B	0.3661	0.6581	0.9813	0.072*
C8B	0.4223 (2)	0.6962 (3)	0.8556 (3)	0.0514 (10)
H8B	0.4454	0.6256	0.8478	0.062*
C9B	0.43639 (18)	0.7761 (3)	0.7875 (3)	0.0406 (8)
C10B	0.39817 (17)	0.8811 (3)	0.7954 (2)	0.0344 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0295 (15)	0.0195 (14)	0.0338 (15)	−0.0026 (11)	0.0021 (12)	−0.0003 (12)
N2	0.0309 (14)	0.0224 (14)	0.0274 (14)	−0.0013 (11)	0.0025 (11)	0.0024 (11)
N3	0.0298 (15)	0.0333 (16)	0.0423 (17)	0.0030 (12)	−0.0031 (12)	−0.0014 (12)
N4	0.0376 (15)	0.0196 (14)	0.0356 (15)	0.0006 (12)	0.0062 (12)	0.0015 (11)
N1A	0.058 (2)	0.049 (2)	0.044 (2)	0.0175 (17)	0.0180 (16)	0.0009 (15)
N2A	0.0279 (16)	0.0462 (19)	0.0457 (18)	−0.0023 (13)	−0.0014 (13)	0.0048 (14)
N1B	0.067 (2)	0.070 (2)	0.050 (2)	−0.0128 (19)	−0.0006 (18)	0.0161 (18)
N2B	0.054 (2)	0.064 (3)	0.072 (2)	0.0110 (17)	0.0032 (19)	−0.018 (2)
C1	0.0333 (18)	0.0265 (17)	0.0213 (16)	0.0010 (14)	0.0027 (13)	0.0027 (13)
C2	0.0289 (18)	0.0361 (19)	0.0351 (19)	0.0000 (15)	−0.0007 (14)	0.0012 (15)
C3	0.0321 (19)	0.052 (2)	0.038 (2)	0.0099 (17)	0.0003 (15)	0.0036 (17)
C4	0.045 (2)	0.038 (2)	0.0336 (19)	0.0172 (17)	0.0032 (16)	0.0048 (16)
C5	0.042 (2)	0.0270 (17)	0.0202 (16)	0.0066 (15)	0.0034 (14)	−0.0010 (13)
C6	0.063 (2)	0.0218 (17)	0.0294 (19)	0.0078 (16)	0.0017 (17)	0.0026 (14)
C7	0.055 (2)	0.0240 (18)	0.038 (2)	−0.0063 (16)	−0.0025 (17)	−0.0004 (15)
C8	0.0406 (19)	0.0282 (18)	0.0340 (19)	−0.0022 (15)	−0.0011 (15)	0.0007 (14)
C9	0.0389 (18)	0.0211 (16)	0.0199 (16)	−0.0015 (14)	0.0016 (14)	−0.0012 (13)
C10	0.0341 (18)	0.0263 (17)	0.0166 (15)	−0.0006 (14)	0.0015 (13)	−0.0019 (12)
C11	0.0280 (17)	0.0256 (17)	0.0198 (16)	−0.0006 (14)	0.0031 (13)	−0.0004 (13)
C12	0.0331 (18)	0.0282 (17)	0.0146 (16)	−0.0002 (14)	0.0028 (13)	−0.0010 (13)
C13	0.0386 (19)	0.044 (2)	0.042 (2)	0.0117 (18)	−0.0039 (16)	−0.0006 (16)
C14	0.050 (2)	0.0298 (19)	0.0299 (19)	0.0106 (16)	0.0010 (16)	0.0010 (14)
C15	0.048 (2)	0.0226 (18)	0.0336 (19)	−0.0010 (15)	0.0067 (16)	0.0005 (14)
C1A	0.045 (2)	0.036 (2)	0.0293 (19)	0.0145 (16)	−0.0003 (16)	0.0048 (15)
C2A	0.079 (3)	0.036 (2)	0.032 (2)	0.017 (2)	−0.0075 (19)	−0.0048 (17)
C3A	0.071 (3)	0.037 (2)	0.051 (2)	−0.008 (2)	−0.029 (2)	−0.0005 (19)
C4A	0.040 (2)	0.047 (2)	0.048 (2)	−0.0062 (17)	−0.0169 (17)	0.0059 (18)
C5A	0.0319 (18)	0.0334 (19)	0.0305 (18)	−0.0006 (14)	−0.0079 (14)	0.0039 (14)
C6A	0.0281 (18)	0.051 (2)	0.040 (2)	−0.0026 (16)	0.0022 (16)	0.0068 (17)
C7A	0.040 (2)	0.050 (2)	0.036 (2)	0.0082 (17)	0.0068 (16)	−0.0053 (16)
C8A	0.046 (2)	0.0325 (19)	0.0333 (19)	−0.0042 (16)	−0.0010 (16)	−0.0041 (15)
C9A	0.0284 (17)	0.0299 (17)	0.0295 (18)	−0.0015 (14)	−0.0035 (14)	0.0068 (14)
C10A	0.0296 (17)	0.0302 (17)	0.0256 (17)	0.0039 (13)	−0.0046 (14)	0.0078 (14)
C1B	0.0345 (19)	0.044 (2)	0.049 (2)	−0.0091 (17)	−0.0123 (17)	0.0052 (18)
C2B	0.059 (2)	0.041 (2)	0.065 (3)	−0.0044 (19)	−0.022 (2)	0.004 (2)
C3B	0.065 (3)	0.036 (2)	0.088 (3)	0.009 (2)	−0.028 (2)	−0.015 (2)
C4B	0.047 (2)	0.063 (3)	0.059 (3)	0.002 (2)	−0.0093 (19)	−0.027 (2)
C5B	0.0336 (19)	0.044 (2)	0.045 (2)	−0.0066 (16)	−0.0081 (17)	−0.0036 (17)
C6B	0.044 (2)	0.079 (3)	0.047 (2)	−0.011 (2)	−0.0019 (18)	0.007 (2)
C7B	0.050 (2)	0.062 (3)	0.067 (3)	−0.022 (2)	−0.017 (2)	0.031 (2)
C8B	0.045 (2)	0.038 (2)	0.071 (3)	−0.0052 (17)	−0.023 (2)	0.005 (2)
C9B	0.0308 (18)	0.044 (2)	0.047 (2)	−0.0023 (16)	−0.0101 (16)	−0.0069 (18)
C10B	0.0308 (17)	0.0348 (19)	0.038 (2)	−0.0050 (15)	−0.0076 (15)	−0.0021 (15)

Geometric parameters (Å, º) top

N1—C11	1.355 (3)	C13—C14	1.364 (4)
N1—C1	1.393 (3)	C13—H13	0.9500
N1—H1	0.86 (3)	C14—C15	1.370 (4)
N2—C11	1.299 (3)	C14—H14	0.9500
N2—C9	1.404 (3)	C15—H15	0.9500
N3—C13	1.334 (4)	C1A—C2A	1.373 (4)
N3—C12	1.338 (3)	C1A—C10A	1.431 (4)
N4—C12	1.328 (3)	C2A—C3A	1.396 (5)
N4—C15	1.335 (3)	C2A—H2A	0.9500
N1A—C1A	1.404 (4)	C3A—C4A	1.358 (5)
N1A—H1C	0.87 (3)	C3A—H3A	0.9500
N1A—H1D	0.93 (3)	C4A—C5A	1.413 (4)
N2A—C9A	1.407 (4)	C4A—H4A	0.9500
N2A—H2C	0.92 (3)	C5A—C6A	1.405 (4)
N2A—H2D	0.87 (3)	C5A—C10A	1.430 (4)
N1B—C1B	1.411 (4)	C6A—C7A	1.356 (4)
N1B—H1E	0.98 (4)	C6A—H6A	0.9500
N1B—H1F	0.98 (4)	C7A—C8A	1.390 (4)
N2B—C9B	1.410 (4)	C7A—H7A	0.9500
N2B—H2E	0.93 (4)	C8A—C9A	1.374 (4)
N2B—H2F	0.91 (4)	C8A—H8A	0.9500
C1—C2	1.374 (4)	C9A—C10A	1.436 (4)
C1—C10	1.408 (4)	C1B—C2B	1.361 (5)
C2—C3	1.406 (4)	C1B—C10B	1.428 (4)
C2—H2	0.9500	C2B—C3B	1.385 (5)
C3—C4	1.360 (4)	C2B—H2B	0.9500
C3—H3	0.9500	C3B—C4B	1.360 (5)
C4—C5	1.402 (4)	C3B—H3B	0.9500
C4—H4	0.9500	C4B—C5B	1.420 (5)
C5—C6	1.420 (4)	C4B—H4B	0.9500
C5—C10	1.421 (4)	C5B—C6B	1.408 (5)
C6—C7	1.364 (4)	C5B—C10B	1.417 (4)
C6—H6	0.9500	C6B—C7B	1.361 (5)
C7—C8	1.395 (4)	C6B—H6B	0.9500
C7—H7	0.9500	C7B—C8B	1.380 (5)
C8—C9	1.377 (4)	C7B—H7B	0.9500
C8—H8	0.9500	C8B—C9B	1.363 (5)
C9—C10	1.417 (4)	C8B—H8B	0.9500
C11—C12	1.486 (4)	C9B—C10B	1.437 (4)

C11—N1—C1	121.8 (2)	C14—C15—H15	118.8
C11—N1—H1	117.2 (19)	C2A—C1A—N1A	119.3 (3)
C1—N1—H1	120.7 (19)	C2A—C1A—C10A	119.2 (3)
C11—N2—C9	116.9 (2)	N1A—C1A—C10A	121.4 (3)
C13—N3—C12	114.6 (3)	C1A—C2A—C3A	121.6 (3)
C12—N4—C15	115.7 (3)	C1A—C2A—H2A	119.2
C1A—N1A—H1C	113 (2)	C3A—C2A—H2A	119.2
C1A—N1A—H1D	113 (2)	C4A—C3A—C2A	120.9 (3)
H1C—N1A—H1D	111 (3)	C4A—C3A—H3A	119.6
C9A—N2A—H2C	108.4 (19)	C2A—C3A—H3A	119.6
C9A—N2A—H2D	115 (2)	C3A—C4A—C5A	119.9 (3)
H2C—N2A—H2D	108 (3)	C3A—C4A—H4A	120.0
C1B—N1B—H1E	110 (2)	C5A—C4A—H4A	120.0
C1B—N1B—H1F	108 (2)	C6A—C5A—C4A	119.7 (3)
H1E—N1B—H1F	115 (3)	C6A—C5A—C10A	120.4 (3)
C9B—N2B—H2E	113 (2)	C4A—C5A—C10A	119.9 (3)
C9B—N2B—H2F	115 (2)	C7A—C6A—C5A	120.5 (3)
H2E—N2B—H2F	108 (3)	C7A—C6A—H6A	119.8
C2—C1—N1	122.7 (3)	C5A—C6A—H6A	119.8
C2—C1—C10	121.6 (3)	C6A—C7A—C8A	120.5 (3)
N1—C1—C10	115.7 (3)	C6A—C7A—H7A	119.7
C1—C2—C3	117.8 (3)	C8A—C7A—H7A	119.7
C1—C2—H2	121.1	C9A—C8A—C7A	121.4 (3)
C3—C2—H2	121.1	C9A—C8A—H8A	119.3
C4—C3—C2	122.1 (3)	C7A—C8A—H8A	119.3
C4—C3—H3	118.9	C8A—C9A—N2A	117.9 (3)
C2—C3—H3	118.9	C8A—C9A—C10A	120.0 (3)
C3—C4—C5	121.0 (3)	N2A—C9A—C10A	122.1 (3)
C3—C4—H4	119.5	C5A—C10A—C1A	118.2 (3)
C5—C4—H4	119.5	C5A—C10A—C9A	116.9 (3)
C4—C5—C6	124.7 (3)	C1A—C10A—C9A	124.9 (3)
C4—C5—C10	117.8 (3)	C2B—C1B—N1B	118.3 (3)
C6—C5—C10	117.5 (3)	C2B—C1B—C10B	119.5 (3)
C7—C6—C5	120.5 (3)	N1B—C1B—C10B	122.2 (3)
C7—C6—H6	119.7	C1B—C2B—C3B	122.4 (4)
C5—C6—H6	119.7	C1B—C2B—H2B	118.8
C6—C7—C8	121.9 (3)	C3B—C2B—H2B	118.8
C6—C7—H7	119.0	C4B—C3B—C2B	120.2 (4)
C8—C7—H7	119.0	C4B—C3B—H3B	119.9
C9—C8—C7	119.7 (3)	C2B—C3B—H3B	119.9
C9—C8—H8	120.1	C3B—C4B—C5B	119.8 (4)
C7—C8—H8	120.1	C3B—C4B—H4B	120.1
C8—C9—N2	119.5 (3)	C5B—C4B—H4B	120.1
C8—C9—C10	119.6 (3)	C6B—C5B—C10B	119.9 (3)
N2—C9—C10	120.9 (3)	C6B—C5B—C4B	120.0 (4)
C1—C10—C9	119.7 (3)	C10B—C5B—C4B	120.1 (3)
C1—C10—C5	119.6 (3)	C7B—C6B—C5B	120.2 (4)
C9—C10—C5	120.7 (3)	C7B—C6B—H6B	119.9
N2—C11—N1	125.0 (3)	C5B—C6B—H6B	119.9
N2—C11—C12	119.6 (3)	C6B—C7B—C8B	120.8 (3)
N1—C11—C12	115.4 (2)	C6B—C7B—H7B	119.6
N4—C12—N3	127.2 (3)	C8B—C7B—H7B	119.6
N4—C12—C11	115.9 (3)	C9B—C8B—C7B	121.5 (3)
N3—C12—C11	116.9 (3)	C9B—C8B—H8B	119.2
N3—C13—C14	123.5 (3)	C7B—C8B—H8B	119.2
N3—C13—H13	118.3	C8B—C9B—N2B	119.8 (3)
C14—C13—H13	118.3	C8B—C9B—C10B	119.7 (3)
C13—C14—C15	116.7 (3)	N2B—C9B—C10B	120.4 (3)
C13—C14—H14	121.6	C5B—C10B—C1B	117.9 (3)
C15—C14—H14	121.6	C5B—C10B—C9B	117.7 (3)
N4—C15—C14	122.3 (3)	C1B—C10B—C9B	124.4 (3)
N4—C15—H15	118.8

C11—N1—C1—C2	178.4 (3)	C1A—C2A—C3A—C4A	−1.9 (5)
C11—N1—C1—C10	−1.3 (4)	C2A—C3A—C4A—C5A	1.3 (5)
N1—C1—C2—C3	179.3 (3)	C3A—C4A—C5A—C6A	−177.9 (3)
C10—C1—C2—C3	−1.1 (4)	C3A—C4A—C5A—C10A	2.9 (5)
C1—C2—C3—C4	−0.4 (5)	C4A—C5A—C6A—C7A	−178.1 (3)
C2—C3—C4—C5	1.2 (5)	C10A—C5A—C6A—C7A	1.1 (5)
C3—C4—C5—C6	179.3 (3)	C5A—C6A—C7A—C8A	2.3 (5)
C3—C4—C5—C10	−0.4 (4)	C6A—C7A—C8A—C9A	−1.6 (5)
C4—C5—C6—C7	−179.5 (3)	C7A—C8A—C9A—N2A	178.4 (3)
C10—C5—C6—C7	0.3 (4)	C7A—C8A—C9A—C10A	−2.4 (4)
C5—C6—C7—C8	0.3 (5)	C6A—C5A—C10A—C1A	174.4 (3)
C6—C7—C8—C9	−0.7 (5)	C4A—C5A—C10A—C1A	−6.4 (4)
C7—C8—C9—N2	−179.5 (3)	C6A—C5A—C10A—C9A	−4.9 (4)
C7—C8—C9—C10	0.7 (4)	C4A—C5A—C10A—C9A	174.3 (3)
C11—N2—C9—C8	178.3 (3)	C2A—C1A—C10A—C5A	5.8 (4)
C11—N2—C9—C10	−1.9 (4)	N1A—C1A—C10A—C5A	−177.6 (3)
C2—C1—C10—C9	−178.7 (3)	C2A—C1A—C10A—C9A	−175.0 (3)
N1—C1—C10—C9	1.0 (4)	N1A—C1A—C10A—C9A	1.6 (4)
C2—C1—C10—C5	1.8 (4)	C8A—C9A—C10A—C5A	5.5 (4)
N1—C1—C10—C5	−178.5 (2)	N2A—C9A—C10A—C5A	−175.3 (3)
C8—C9—C10—C1	−179.6 (3)	C8A—C9A—C10A—C1A	−173.7 (3)
N2—C9—C10—C1	0.5 (4)	N2A—C9A—C10A—C1A	5.4 (4)
C8—C9—C10—C5	−0.1 (4)	N1B—C1B—C2B—C3B	−179.6 (3)
N2—C9—C10—C5	−180.0 (2)	C10B—C1B—C2B—C3B	−0.6 (5)
C4—C5—C10—C1	−1.1 (4)	C1B—C2B—C3B—C4B	−1.3 (6)
C6—C5—C10—C1	179.2 (3)	C2B—C3B—C4B—C5B	1.4 (5)
C4—C5—C10—C9	179.4 (3)	C3B—C4B—C5B—C6B	−178.4 (3)
C6—C5—C10—C9	−0.3 (4)	C3B—C4B—C5B—C10B	0.4 (5)
C9—N2—C11—N1	1.8 (4)	C10B—C5B—C6B—C7B	−1.9 (5)
C9—N2—C11—C12	−177.6 (2)	C4B—C5B—C6B—C7B	176.9 (3)
C1—N1—C11—N2	−0.2 (4)	C5B—C6B—C7B—C8B	3.5 (5)
C1—N1—C11—C12	179.2 (2)	C6B—C7B—C8B—C9B	−0.7 (5)
C15—N4—C12—N3	−0.3 (4)	C7B—C8B—C9B—N2B	178.2 (3)
C15—N4—C12—C11	−179.3 (2)	C7B—C8B—C9B—C10B	−3.6 (5)
C13—N3—C12—N4	0.4 (4)	C6B—C5B—C10B—C1B	176.6 (3)
C13—N3—C12—C11	179.4 (2)	C4B—C5B—C10B—C1B	−2.2 (4)
N2—C11—C12—N4	177.2 (2)	C6B—C5B—C10B—C9B	−2.3 (4)
N1—C11—C12—N4	−2.2 (3)	C4B—C5B—C10B—C9B	178.9 (3)
N2—C11—C12—N3	−1.9 (4)	C2B—C1B—C10B—C5B	2.3 (4)
N1—C11—C12—N3	178.7 (2)	N1B—C1B—C10B—C5B	−178.7 (3)
C12—N3—C13—C14	−0.5 (4)	C2B—C1B—C10B—C9B	−178.9 (3)
N3—C13—C14—C15	0.5 (5)	N1B—C1B—C10B—C9B	0.1 (5)
C12—N4—C15—C14	0.2 (4)	C8B—C9B—C10B—C5B	5.0 (4)
C13—C14—C15—N4	−0.3 (4)	N2B—C9B—C10B—C5B	−176.8 (3)
N1A—C1A—C2A—C3A	−178.4 (3)	C8B—C9B—C10B—C1B	−173.8 (3)
C10A—C1A—C2A—C3A	−1.8 (5)	N2B—C9B—C10B—C1B	4.4 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2Aⁱ	0.86 (3)	2.30 (3)	3.077 (4)	151 (2)
N1A—H1C···N2ⁱⁱ	0.87 (3)	2.42 (3)	3.153 (4)	142 (3)
N2A—H2C···N2	0.92 (3)	2.27 (3)	3.092 (4)	149 (3)
N2A—H2D···N1A	0.87 (3)	2.27 (3)	2.753 (5)	115 (2)
N1B—H1F···N2B	0.98 (4)	2.12 (3)	2.710 (5)	117 (2)

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₀N₄·2C₁₀H₁₀N₂
M_r	562.67
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	17.083 (2), 12.139 (3), 13.597 (2)
β (°)	90.76 (1)
V (Å³)	2819.4 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.50 × 0.45 × 0.10

Data collection
Diffractometer	Bruker–Nonius KappaCCD
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.960, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	22722, 5184, 2799
R_int	0.080
(sin θ/λ)_max (Å⁻¹)	0.604

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.142, 1.06
No. of reflections	5184
No. of parameters	415
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.18

Computer programs: COLLECT (Nonius, 1999), DIRAX/LSQ (Duisenberg et al., 2000), EVALCCD (Duisenberg et al., 2003), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2Aⁱ	0.86 (3)	2.30 (3)	3.077 (4)	151 (2)
N1A—H1C···N2ⁱⁱ	0.87 (3)	2.42 (3)	3.153 (4)	142 (3)
N2A—H2C···N2	0.92 (3)	2.27 (3)	3.092 (4)	149 (3)
N2A—H2D···N1A	0.87 (3)	2.27 (3)	2.753 (5)	115 (2)
N1B—H1F···N2B	0.98 (4)	2.12 (3)	2.710 (5)	117 (2)

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

Acknowledgements

The authors thank the Centro Interdipartimentale di Metodologie Chimico–Fisiche, Università degli Studi di Napoli "Federico II" for the X-ray facilities.

References

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