(S)-Benzyl 3-phenyl­carbamoyl-1,2,3,4-tetra­hydro­isoquinoline-2-carboxyl­ate

Naicker, T.; Chelopo, M.; Govender, T.; Kruger, H.G.; Maguire, G.E.M.

doi:10.1107/S1600536812007969

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 68| Part 3| March 2012| Page o883

doi:10.1107/S1600536812007969

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(S)-Benzyl 3-phenylcarbamoyl-1,2,3,4-tetrahydroisoquinoline-2-carboxylate

Tricia Naicker,^a Madichaba Chelopo,^a Thavendran Govender,^a Hendrick G. Kruger ^b and Glenn E. M. Maguire ^b ^*

^aSchool of Pharmacy and Pharmacology, University of KwaZulu-Natal, Durban 4000, South Africa, and ^bSchool of Chemistry, University of KwaZulu-Natal, Durban 4000, South Africa
^*Correspondence e-mail: maguireg@ukzn.ac.za

(Received 13 February 2012; accepted 22 February 2012; online 29 February 2012)

There are two independent molecules in the asymmetric unit of the title compound, C₂₄H₂₂N₂O₃. The heterocyclic ring assumes a twisted boat conformation and N—H⋯O interactions help to construct the three-dimensional network within the crystal packing.

Related literature

For background literature, see: Sridharan et al. (2011 ). For related literature on the synthesis, see: Peters et al. (2010 ). For related crystal strucutures, see: Naicker et al. (2011a , 2011b ).

Experimental

Crystal data

C₂₄H₂₂N₂O₃
M_r = 386.44
Monoclinic, P 2₁
a = 13.0338 (5) Å
b = 10.8079 (2) Å
c = 14.0431 (5) Å
β = 92.031 (1)°
V = 1976.98 (11) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 173 K
0.34 × 0.34 × 0.23 mm

Data collection

Nonius KappaCCD diffractometer
9418 measured reflections
4958 independent reflections
4347 reflections with I > 2σ(I)
R_int = 0.014

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.095
S = 1.15
4958 reflections
532 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.54 e Å⁻³
Δρ_min = −0.57 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2A—H2A⋯O1Bⁱ	0.97 (1)	1.97 (1)	2.9213 (16)	167 (1)
N2B—H2B⋯O2Bⁱⁱ	0.97 (1)	1.92 (1)	2.8904 (16)	176 (1)
Symmetry codes: (i) $[-x+1, y-{\script{1\over 2}}, -z]$ ; (ii) $[-x+2, y-{\script{1\over 2}}, -z]$ .

Data collection: COLLECT (Nonius, 2000 ); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997 ); data reduction: DENZO–SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812007969/hg5180sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812007969/hg5180Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812007969/hg5180Isup3.cml

checkCIF report

Comment top

The tetrahydroisoquinoline (TIQ) molecule and its derivatives have been widely investigated for their biological and pharmaceutical properties (Sridharan et al. 2011). Our research currently focuses on the evaluation of novel TIQ compounds for their potential biological activity and as a source of chirality in the synthesis of novel asymmetric catalysts.

The title compound is a precursor in the synthesis of novel asymmetric catalysts and containing a tetrahydroisoquinoline framework (Peters et al. 2010).

The title structure was derived from commercially available S-phenyl glycine and formaldehyde. The absolute stereochemistry was confirmed to be S at the C9 position from proton NMR spectroscopy (Peters et al. 2010).

The structure has two molecules in the asymmetric unit (Fig. 1). The molecules display intermolecular hydrogen bonding via the amide and carbamate carbonyl group. (Table 1). This bonding arrangement creates chains which link the molecules together resulting in layers parallel to the 100 plane. (Fig. 2).

From the crystal structure it is evident that the N-containing six membered ring assumes a twisted boat conformation [(Q) = 0.6507 (15) Å, θ = 90.29 (13)°, ϕ = 237.65 (13)°] which is peculiar since this ring in similar TIQ deriviatives displays either a half chair or boat form (Naicker et al. 2011a and 2011b). The N-Cbz group is staggered to the ester group at the C9 position, the torsion angle is H1A—C1A—N1A—C17A -67.5 (2)°.

Related literature top

For background literature, see: Sridharan et al. (2011. For related literature on the synthesis, see: Peters et al. (2010). For related crystal strucutures, see: Naicker et al. (2011a, 2011b).

Experimental top

(S)-2-(Benzyloxycarbonyl)-1,2,3,4-tetrahydroisoquinoline-3- carboxylic acid (1.5 g, 4.8 mmol) was dissolved in DMF (15 ml) followed by addition of EDC.HCl (1.1 g, 5.8 mmol), HOBt (0.81 g, 5.3 mmol), a catalytic amount of DMAP and aniline (5.3 mmol). The reaction mixture was then stirred at room temperature until no more starting material could be detected by TLC analysis (approximately 1 h). The reaction mixture was poured into 30 volumes of chilled water; the mixture was then extracted twice with ethyl acetate. The extracts were combined, washed with 10% aqueous HCl to remove latent EDC urea, dried over anhydrous magnesium sulfate and then concentrated to dryness affording the crude product which was purified by column chromatography. (Hexane:EtOAc 60:40 R_f 1/2).

Melting point = 410–412 K

Recrystallization from ethyl acetate at room temperature afforded crystals suitable for X-ray analysis.

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 40% probability level. Hydrogen atoms have been omitted for clarity.
	Fig. 2. A partial projection of the title compound in the [100] plane.

(S)-Benzyl 3-phenylcarbamoyl-1,2,3,4-tetrahydroisoquinoline-2-carboxylate top

Crystal data top

C₂₄H₂₂N₂O₃	F(000) = 816
M_r = 386.44	D_x = 1.298 Mg m⁻³
Monoclinic, P2₁	Melting point: 411 K
Hall symbol: P 2yb	Mo Kα radiation, λ = 0.71073 Å
a = 13.0338 (5) Å	Cell parameters from 9418 reflections
b = 10.8079 (2) Å	θ = 2.5–27.9°
c = 14.0431 (5) Å	µ = 0.09 mm⁻¹
β = 92.031 (1)°	T = 173 K
V = 1976.98 (11) Å³	Block, colourless
Z = 4	0.34 × 0.34 × 0.23 mm

Data collection top

Nonius KappaCCD diffractometer	4347 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.014
Graphite monochromator	θ_max = 27.9°, θ_min = 2.5°
1.2° ϕ scans and ω scans	h = −17→17
9418 measured reflections	k = −14→14
4958 independent reflections	l = −18→18

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)] = 0.039	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.095	w = 1/[σ²(F_o²) + (0.0622P)²] where P = (F_o² + 2F_c²)/3
S = 1.15	(Δ/σ)_max = 0.001
4958 reflections	Δρ_max = 0.54 e Å⁻³
532 parameters	Δρ_min = −0.57 e Å⁻³
3 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: 0.046 (3)

Crystal data top

C₂₄H₂₂N₂O₃	V = 1976.98 (11) Å³
M_r = 386.44	Z = 4
Monoclinic, P2₁	Mo Kα radiation
a = 13.0338 (5) Å	µ = 0.09 mm⁻¹
b = 10.8079 (2) Å	T = 173 K
c = 14.0431 (5) Å	0.34 × 0.34 × 0.23 mm
β = 92.031 (1)°

Data collection top

Nonius KappaCCD diffractometer	4347 reflections with I > 2σ(I)
9418 measured reflections	R_int = 0.014
4958 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	3 restraints
wR(F²) = 0.095	H atoms treated by a mixture of independent and constrained refinement
S = 1.15	Δρ_max = 0.54 e Å⁻³
4958 reflections	Δρ_min = −0.57 e Å⁻³
532 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
O1A	0.52998 (11)	0.38204 (15)	0.11077 (10)	0.0406 (4)
O2A	0.29082 (11)	0.58944 (14)	−0.03510 (10)	0.0403 (4)
O3A	0.27453 (11)	0.43269 (13)	0.07094 (10)	0.0361 (3)
N1A	0.38659 (12)	0.41285 (15)	−0.04295 (11)	0.0293 (3)
N2A	0.43006 (11)	0.22263 (14)	0.16104 (10)	0.0271 (3)
H2A	0.3726 (11)	0.1696 (17)	0.1431 (14)	0.036 (6)*
C1A	0.43931 (15)	0.45372 (19)	−0.12855 (14)	0.0327 (4)
H1A1	0.5124	0.4710	−0.1122	0.039*
H1A2	0.4073	0.5307	−0.1537	0.039*
C2A	0.43120 (14)	0.35392 (19)	−0.20221 (13)	0.0303 (4)
C3A	0.40204 (16)	0.3749 (2)	−0.29716 (14)	0.0376 (5)
H3A	0.3880	0.4566	−0.3189	0.045*
C4A	0.39357 (17)	0.2763 (2)	−0.35980 (15)	0.0419 (5)
H4A	0.3740	0.2907	−0.4247	0.050*
C5A	0.41327 (16)	0.1573 (2)	−0.32889 (14)	0.0386 (5)
H5A	0.4069	0.0901	−0.3723	0.046*
C6A	0.44253 (14)	0.1354 (2)	−0.23377 (13)	0.0320 (4)
H6A	0.4559	0.0535	−0.2122	0.038*
C7A	0.45189 (13)	0.23411 (19)	−0.17097 (12)	0.0283 (4)
C8A	0.48319 (14)	0.21942 (18)	−0.06702 (12)	0.0292 (4)
H8A1	0.5541	0.2504	−0.0562	0.035*
H8A2	0.4824	0.1306	−0.0499	0.035*
C9A	0.41022 (14)	0.29101 (18)	−0.00241 (12)	0.0265 (4)
H9A	0.3451	0.2431	0.0034	0.032*
C10A	0.46280 (14)	0.30510 (17)	0.09645 (12)	0.0275 (4)
C11A	0.46730 (14)	0.20560 (18)	0.25604 (12)	0.0285 (4)
C12A	0.55769 (15)	0.2588 (2)	0.29217 (14)	0.0376 (5)
H12A	0.5975	0.3108	0.2533	0.045*
C13A	0.58892 (17)	0.2347 (2)	0.38603 (15)	0.0444 (5)
H13A	0.6505	0.2713	0.4110	0.053*
C14A	0.53305 (17)	0.1593 (2)	0.44374 (14)	0.0431 (5)
H14A	0.5557	0.1437	0.5076	0.052*
C15A	0.44321 (17)	0.1067 (2)	0.40710 (14)	0.0418 (5)
H15A	0.4040	0.0541	0.4460	0.050*
C16A	0.41032 (15)	0.1303 (2)	0.31416 (13)	0.0351 (4)
H16A	0.3481	0.0945	0.2899	0.042*
C17A	0.31546 (14)	0.48742 (19)	−0.00535 (13)	0.0303 (4)
C18A	0.20156 (17)	0.5056 (2)	0.12288 (15)	0.0445 (5)
H18A	0.1320	0.4979	0.0928	0.053*
H18B	0.2215	0.5940	0.1227	0.053*
C19A	0.20244 (16)	0.4573 (2)	0.22276 (15)	0.0376 (5)
C20A	0.29385 (17)	0.4508 (2)	0.27638 (16)	0.0448 (5)
H20A	0.3562	0.4757	0.2490	0.054*
C21A	0.2948 (2)	0.4084 (3)	0.36910 (17)	0.0517 (6)
H21A	0.3577	0.4044	0.4052	0.062*
C22A	0.2051 (2)	0.3718 (3)	0.40947 (17)	0.0554 (6)
H22A	0.2060	0.3425	0.4733	0.066*
C23A	0.1148 (2)	0.3778 (3)	0.35762 (17)	0.0528 (6)
H23A	0.0528	0.3524	0.3854	0.063*
C24A	0.11304 (18)	0.4206 (2)	0.26446 (17)	0.0448 (5)
H24A	0.0497	0.4248	0.2290	0.054*
O1B	0.72563 (11)	0.54812 (14)	−0.09056 (10)	0.0384 (3)
O2B	0.96842 (10)	0.80430 (13)	0.02030 (9)	0.0331 (3)
O3B	0.97586 (10)	0.62280 (13)	−0.06036 (9)	0.0312 (3)
N1B	0.86643 (11)	0.64064 (15)	0.05632 (10)	0.0278 (3)
N2B	0.83736 (12)	0.38701 (15)	−0.10304 (11)	0.0280 (3)
H2B	0.9045 (7)	0.360 (2)	−0.0796 (14)	0.035 (6)*
C1B	0.82427 (14)	0.70473 (19)	0.13913 (12)	0.0292 (4)
H1B1	0.7513	0.7258	0.1253	0.035*
H1B2	0.8624	0.7827	0.1511	0.035*
C2B	0.83260 (13)	0.6241 (2)	0.22607 (13)	0.0307 (4)
C3B	0.86246 (15)	0.6692 (2)	0.31573 (13)	0.0378 (5)
H3B	0.8809	0.7538	0.3235	0.045*
C4B	0.86516 (17)	0.5907 (3)	0.39320 (15)	0.0465 (6)
H4B	0.8843	0.6216	0.4546	0.056*
C5B	0.84012 (17)	0.4673 (3)	0.38180 (16)	0.0471 (6)
H5B	0.8427	0.4136	0.4354	0.057*
C6B	0.81103 (16)	0.4211 (2)	0.29225 (15)	0.0404 (5)
H6B	0.7948	0.3359	0.2845	0.048*
C7B	0.80592 (13)	0.5004 (2)	0.21426 (13)	0.0315 (4)
C8B	0.77060 (14)	0.46164 (19)	0.11544 (13)	0.0308 (4)
H8B1	0.7011	0.4953	0.1011	0.037*
H8B2	0.7664	0.3703	0.1123	0.037*
C9B	0.84478 (13)	0.50845 (17)	0.04082 (12)	0.0264 (4)
H9B	0.9105	0.4611	0.0476	0.032*
C10B	0.79667 (13)	0.48517 (18)	−0.05885 (13)	0.0268 (4)
C11B	0.80969 (14)	0.33996 (17)	−0.19506 (13)	0.0272 (4)
C12B	0.71076 (15)	0.3490 (2)	−0.23410 (15)	0.0362 (4)
H12B	0.6583	0.3880	−0.1997	0.043*
C13B	0.68944 (16)	0.3003 (2)	−0.32388 (16)	0.0437 (5)
H13B	0.6219	0.3073	−0.3511	0.052*
C14B	0.76409 (16)	0.2419 (2)	−0.37446 (14)	0.0387 (5)
H14B	0.7484	0.2095	−0.4362	0.046*
C15B	0.86218 (15)	0.2309 (2)	−0.33438 (14)	0.0374 (5)
H15B	0.9141	0.1899	−0.3682	0.045*
C16B	0.88465 (15)	0.27978 (19)	−0.24505 (14)	0.0332 (4)
H16B	0.9521	0.2720	−0.2177	0.040*
C17B	0.93931 (13)	0.69790 (18)	0.00696 (12)	0.0258 (4)
C18B	1.05654 (15)	0.6733 (2)	−0.11746 (13)	0.0341 (4)
H18C	1.1244	0.6583	−0.0856	0.041*
H18D	1.0472	0.7637	−0.1251	0.041*
C19B	1.05156 (15)	0.61123 (18)	−0.21351 (13)	0.0326 (4)
C20B	0.95807 (17)	0.5933 (2)	−0.26206 (14)	0.0387 (5)
H20B	0.8960	0.6143	−0.2325	0.046*
C21B	0.95489 (19)	0.5449 (2)	−0.35342 (15)	0.0463 (5)
H21B	0.8906	0.5319	−0.3859	0.056*
C22B	1.0445 (2)	0.5156 (3)	−0.39740 (16)	0.0524 (6)
H22B	1.0422	0.4838	−0.4605	0.063*
C23B	1.1380 (2)	0.5328 (3)	−0.34923 (18)	0.0543 (6)
H23B	1.1999	0.5130	−0.3794	0.065*
C24B	1.14128 (18)	0.5788 (2)	−0.25690 (16)	0.0442 (5)
H24B	1.2054	0.5881	−0.2234	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1A	0.0425 (8)	0.0410 (8)	0.0379 (8)	−0.0185 (7)	−0.0053 (6)	0.0001 (7)
O2A	0.0396 (8)	0.0343 (8)	0.0468 (8)	0.0089 (6)	0.0009 (6)	0.0023 (7)
O3A	0.0377 (8)	0.0349 (7)	0.0362 (7)	0.0066 (6)	0.0100 (6)	0.0001 (6)
N1A	0.0309 (8)	0.0277 (8)	0.0296 (8)	0.0016 (6)	0.0033 (6)	0.0015 (6)
N2A	0.0261 (7)	0.0283 (8)	0.0267 (7)	−0.0031 (6)	−0.0026 (6)	−0.0015 (6)
C1A	0.0318 (9)	0.0300 (10)	0.0369 (10)	−0.0014 (8)	0.0071 (8)	0.0061 (8)
C2A	0.0227 (9)	0.0369 (10)	0.0317 (9)	−0.0011 (8)	0.0053 (7)	0.0047 (8)
C3A	0.0330 (10)	0.0470 (12)	0.0330 (10)	0.0055 (9)	0.0055 (8)	0.0112 (9)
C4A	0.0368 (11)	0.0620 (15)	0.0269 (10)	0.0019 (10)	0.0009 (8)	0.0073 (9)
C5A	0.0359 (11)	0.0520 (13)	0.0281 (9)	−0.0042 (10)	0.0040 (8)	−0.0061 (9)
C6A	0.0292 (9)	0.0362 (10)	0.0310 (9)	−0.0017 (8)	0.0069 (7)	−0.0010 (8)
C7A	0.0219 (8)	0.0354 (10)	0.0278 (9)	0.0001 (8)	0.0050 (7)	0.0018 (8)
C8A	0.0290 (9)	0.0307 (10)	0.0276 (9)	0.0032 (8)	−0.0014 (7)	0.0005 (8)
C9A	0.0272 (9)	0.0263 (9)	0.0258 (8)	−0.0006 (7)	−0.0003 (7)	−0.0005 (7)
C10A	0.0276 (9)	0.0260 (9)	0.0290 (9)	−0.0007 (7)	0.0003 (7)	−0.0033 (7)
C11A	0.0297 (9)	0.0299 (9)	0.0259 (8)	0.0028 (8)	0.0007 (7)	−0.0029 (7)
C12A	0.0331 (10)	0.0456 (12)	0.0339 (10)	−0.0074 (9)	−0.0034 (8)	0.0026 (9)
C13A	0.0401 (11)	0.0568 (14)	0.0354 (11)	−0.0064 (11)	−0.0091 (9)	−0.0029 (10)
C14A	0.0485 (13)	0.0555 (14)	0.0251 (9)	0.0025 (11)	−0.0023 (8)	−0.0030 (9)
C15A	0.0470 (12)	0.0497 (13)	0.0292 (9)	−0.0031 (11)	0.0065 (8)	0.0003 (9)
C16A	0.0339 (10)	0.0395 (11)	0.0318 (9)	−0.0058 (9)	0.0005 (7)	−0.0024 (8)
C17A	0.0279 (9)	0.0301 (10)	0.0328 (9)	−0.0003 (8)	−0.0024 (7)	−0.0018 (8)
C18A	0.0420 (12)	0.0477 (13)	0.0445 (12)	0.0145 (10)	0.0128 (9)	−0.0019 (11)
C19A	0.0381 (11)	0.0344 (11)	0.0408 (11)	0.0050 (9)	0.0088 (8)	−0.0091 (9)
C20A	0.0340 (11)	0.0525 (14)	0.0483 (12)	0.0062 (10)	0.0069 (9)	−0.0081 (10)
C21A	0.0509 (14)	0.0598 (15)	0.0444 (12)	0.0135 (12)	0.0005 (10)	−0.0093 (12)
C22A	0.0738 (18)	0.0526 (15)	0.0406 (12)	0.0127 (13)	0.0136 (12)	−0.0051 (11)
C23A	0.0530 (14)	0.0539 (15)	0.0530 (14)	−0.0052 (12)	0.0228 (12)	−0.0081 (12)
C24A	0.0379 (11)	0.0492 (13)	0.0478 (12)	−0.0010 (10)	0.0071 (9)	−0.0114 (11)
O1B	0.0355 (8)	0.0372 (8)	0.0418 (8)	0.0137 (6)	−0.0108 (6)	−0.0076 (6)
O2B	0.0318 (7)	0.0322 (7)	0.0351 (7)	−0.0066 (6)	−0.0020 (5)	−0.0033 (6)
O3B	0.0314 (7)	0.0310 (7)	0.0315 (6)	−0.0041 (6)	0.0074 (5)	−0.0031 (6)
N1B	0.0278 (7)	0.0276 (8)	0.0278 (7)	−0.0016 (6)	0.0013 (6)	−0.0023 (6)
N2B	0.0245 (7)	0.0296 (8)	0.0298 (7)	0.0036 (6)	−0.0023 (6)	−0.0009 (7)
C1B	0.0251 (9)	0.0343 (10)	0.0282 (9)	0.0038 (8)	0.0002 (7)	−0.0041 (8)
C2B	0.0208 (8)	0.0412 (11)	0.0304 (9)	0.0020 (8)	0.0020 (7)	−0.0014 (8)
C3B	0.0292 (10)	0.0521 (13)	0.0319 (10)	−0.0004 (9)	−0.0005 (8)	−0.0035 (9)
C4B	0.0402 (12)	0.0689 (16)	0.0303 (10)	−0.0015 (11)	−0.0028 (9)	−0.0006 (11)
C5B	0.0406 (12)	0.0653 (16)	0.0355 (11)	0.0028 (11)	0.0018 (9)	0.0143 (11)
C6B	0.0341 (11)	0.0471 (13)	0.0405 (11)	0.0006 (10)	0.0076 (9)	0.0088 (10)
C7B	0.0207 (8)	0.0429 (11)	0.0312 (9)	0.0014 (8)	0.0036 (7)	0.0012 (8)
C8B	0.0259 (9)	0.0327 (10)	0.0340 (9)	−0.0033 (8)	0.0025 (7)	0.0003 (8)
C9B	0.0235 (8)	0.0255 (9)	0.0301 (9)	0.0010 (7)	0.0004 (7)	0.0002 (7)
C10B	0.0221 (8)	0.0275 (9)	0.0308 (9)	−0.0004 (7)	0.0003 (7)	0.0006 (7)
C11B	0.0273 (9)	0.0229 (8)	0.0311 (9)	−0.0004 (7)	−0.0010 (7)	0.0005 (7)
C12B	0.0268 (10)	0.0383 (11)	0.0433 (11)	0.0022 (8)	−0.0023 (8)	−0.0081 (9)
C13B	0.0324 (11)	0.0472 (13)	0.0504 (13)	0.0009 (10)	−0.0117 (9)	−0.0095 (11)
C14B	0.0428 (11)	0.0390 (11)	0.0338 (10)	−0.0017 (9)	−0.0062 (8)	−0.0077 (9)
C15B	0.0358 (10)	0.0391 (12)	0.0373 (10)	0.0026 (9)	0.0028 (8)	−0.0064 (9)
C16B	0.0271 (9)	0.0358 (11)	0.0364 (10)	0.0034 (8)	−0.0022 (8)	−0.0028 (8)
C17B	0.0216 (8)	0.0307 (9)	0.0248 (8)	−0.0003 (7)	−0.0043 (6)	−0.0002 (7)
C18B	0.0282 (9)	0.0408 (11)	0.0336 (9)	−0.0074 (8)	0.0069 (8)	−0.0003 (8)
C19B	0.0376 (10)	0.0288 (9)	0.0316 (9)	−0.0012 (8)	0.0038 (8)	0.0048 (8)
C20B	0.0391 (11)	0.0431 (12)	0.0342 (10)	−0.0024 (9)	0.0051 (8)	0.0045 (9)
C21B	0.0564 (14)	0.0485 (13)	0.0335 (11)	−0.0035 (11)	−0.0051 (10)	0.0023 (10)
C22B	0.0716 (16)	0.0538 (15)	0.0320 (11)	0.0096 (13)	0.0053 (11)	−0.0044 (10)
C23B	0.0538 (14)	0.0630 (16)	0.0468 (13)	0.0187 (13)	0.0120 (11)	−0.0046 (12)
C24B	0.0419 (12)	0.0506 (13)	0.0405 (11)	0.0070 (10)	0.0054 (9)	0.0003 (10)

Geometric parameters (Å, º) top

O1A—C10A	1.219 (2)	O1B—C10B	1.220 (2)
O2A—C17A	1.218 (2)	O2B—C17B	1.223 (2)
O3A—C17A	1.350 (2)	O3B—C17B	1.346 (2)
O3A—C18A	1.452 (2)	O3B—C18B	1.451 (2)
N1A—C17A	1.350 (2)	N1B—C17B	1.346 (2)
N1A—C9A	1.463 (2)	N1B—C9B	1.471 (2)
N1A—C1A	1.473 (2)	N1B—C1B	1.476 (2)
N2A—C10A	1.352 (2)	N2B—C10B	1.347 (2)
N2A—C11A	1.415 (2)	N2B—C11B	1.423 (2)
N2A—H2A	0.969 (2)	N2B—H2B	0.969 (2)
C1A—C2A	1.496 (3)	C1B—C2B	1.501 (3)
C1A—H1A1	0.9900	C1B—H1B1	0.9900
C1A—H1A2	0.9900	C1B—H1B2	0.9900
C2A—C7A	1.390 (3)	C2B—C7B	1.390 (3)
C2A—C3A	1.392 (3)	C2B—C3B	1.393 (3)
C3A—C4A	1.384 (3)	C3B—C4B	1.380 (3)
C3A—H3A	0.9500	C3B—H3B	0.9500
C4A—C5A	1.379 (4)	C4B—C5B	1.381 (4)
C4A—H4A	0.9500	C4B—H4B	0.9500
C5A—C6A	1.396 (3)	C5B—C6B	1.393 (3)
C5A—H5A	0.9500	C5B—H5B	0.9500
C6A—C7A	1.387 (3)	C6B—C7B	1.390 (3)
C6A—H6A	0.9500	C6B—H6B	0.9500
C7A—C8A	1.510 (2)	C7B—C8B	1.506 (3)
C8A—C9A	1.545 (2)	C8B—C9B	1.536 (2)
C8A—H8A1	0.9900	C8B—H8B1	0.9900
C8A—H8A2	0.9900	C8B—H8B2	0.9900
C9A—C10A	1.534 (2)	C9B—C10B	1.534 (2)
C9A—H9A	1.0000	C9B—H9B	1.0000
C11A—C16A	1.387 (3)	C11B—C16B	1.385 (3)
C11A—C12A	1.391 (3)	C11B—C12B	1.386 (3)
C12A—C13A	1.390 (3)	C12B—C13B	1.385 (3)
C12A—H12A	0.9500	C12B—H12B	0.9500
C13A—C14A	1.376 (3)	C13B—C14B	1.378 (3)
C13A—H13A	0.9500	C13B—H13B	0.9500
C14A—C15A	1.385 (3)	C14B—C15B	1.384 (3)
C14A—H14A	0.9500	C14B—H14B	0.9500
C15A—C16A	1.383 (3)	C15B—C16B	1.383 (3)
C15A—H15A	0.9500	C15B—H15B	0.9500
C16A—H16A	0.9500	C16B—H16B	0.9500
C18A—C19A	1.497 (3)	C18B—C19B	1.505 (3)
C18A—H18A	0.9900	C18B—H18C	0.9900
C18A—H18B	0.9900	C18B—H18D	0.9900
C19A—C24A	1.381 (3)	C19B—C24B	1.383 (3)
C19A—C20A	1.388 (3)	C19B—C20B	1.389 (3)
C20A—C21A	1.380 (3)	C20B—C21B	1.385 (3)
C20A—H20A	0.9500	C20B—H20B	0.9500
C21A—C22A	1.375 (4)	C21B—C22B	1.378 (4)
C21A—H21A	0.9500	C21B—H21B	0.9500
C22A—C23A	1.363 (4)	C22B—C23B	1.384 (4)
C22A—H22A	0.9500	C22B—H22B	0.9500
C23A—C24A	1.387 (3)	C23B—C24B	1.388 (3)
C23A—H23A	0.9500	C23B—H23B	0.9500
C24A—H24A	0.9500	C24B—H24B	0.9500

C17A—O3A—C18A	116.42 (16)	C17B—O3B—C18B	116.29 (15)
C17A—N1A—C9A	121.54 (15)	C17B—N1B—C9B	120.36 (15)
C17A—N1A—C1A	119.13 (16)	C17B—N1B—C1B	118.62 (15)
C9A—N1A—C1A	119.31 (15)	C9B—N1B—C1B	119.83 (15)
C10A—N2A—C11A	127.77 (15)	C10B—N2B—C11B	127.47 (16)
C10A—N2A—H2A	118.3 (13)	C10B—N2B—H2B	116.6 (13)
C11A—N2A—H2A	113.9 (13)	C11B—N2B—H2B	113.4 (13)
N1A—C1A—C2A	108.94 (15)	N1B—C1B—C2B	110.49 (16)
N1A—C1A—H1A1	109.9	N1B—C1B—H1B1	109.6
C2A—C1A—H1A1	109.9	C2B—C1B—H1B1	109.6
N1A—C1A—H1A2	109.9	N1B—C1B—H1B2	109.6
C2A—C1A—H1A2	109.9	C2B—C1B—H1B2	109.6
H1A1—C1A—H1A2	108.3	H1B1—C1B—H1B2	108.1
C7A—C2A—C3A	119.81 (19)	C7B—C2B—C3B	120.36 (19)
C7A—C2A—C1A	116.44 (16)	C7B—C2B—C1B	116.80 (17)
C3A—C2A—C1A	123.73 (19)	C3B—C2B—C1B	122.81 (19)
C4A—C3A—C2A	119.8 (2)	C4B—C3B—C2B	119.7 (2)
C4A—C3A—H3A	120.1	C4B—C3B—H3B	120.1
C2A—C3A—H3A	120.1	C2B—C3B—H3B	120.1
C5A—C4A—C3A	120.58 (18)	C3B—C4B—C5B	120.2 (2)
C5A—C4A—H4A	119.7	C3B—C4B—H4B	119.9
C3A—C4A—H4A	119.7	C5B—C4B—H4B	119.9
C4A—C5A—C6A	120.0 (2)	C4B—C5B—C6B	120.4 (2)
C4A—C5A—H5A	120.0	C4B—C5B—H5B	119.8
C6A—C5A—H5A	120.0	C6B—C5B—H5B	119.8
C7A—C6A—C5A	119.5 (2)	C7B—C6B—C5B	119.6 (2)
C7A—C6A—H6A	120.2	C7B—C6B—H6B	120.2
C5A—C6A—H6A	120.2	C5B—C6B—H6B	120.2
C6A—C7A—C2A	120.27 (17)	C2B—C7B—C6B	119.61 (19)
C6A—C7A—C8A	123.26 (18)	C2B—C7B—C8B	116.40 (17)
C2A—C7A—C8A	116.46 (17)	C6B—C7B—C8B	124.0 (2)
C7A—C8A—C9A	111.36 (14)	C7B—C8B—C9B	110.96 (15)
C7A—C8A—H8A1	109.4	C7B—C8B—H8B1	109.4
C9A—C8A—H8A1	109.4	C9B—C8B—H8B1	109.4
C7A—C8A—H8A2	109.4	C7B—C8B—H8B2	109.4
C9A—C8A—H8A2	109.4	C9B—C8B—H8B2	109.4
H8A1—C8A—H8A2	108.0	H8B1—C8B—H8B2	108.0
N1A—C9A—C10A	110.12 (15)	N1B—C9B—C10B	111.37 (15)
N1A—C9A—C8A	110.34 (14)	N1B—C9B—C8B	109.93 (15)
C10A—C9A—C8A	108.46 (14)	C10B—C9B—C8B	108.76 (14)
N1A—C9A—H9A	109.3	N1B—C9B—H9B	108.9
C10A—C9A—H9A	109.3	C10B—C9B—H9B	108.9
C8A—C9A—H9A	109.3	C8B—C9B—H9B	108.9
O1A—C10A—N2A	125.53 (16)	O1B—C10B—N2B	125.23 (17)
O1A—C10A—C9A	120.82 (17)	O1B—C10B—C9B	121.45 (17)
N2A—C10A—C9A	113.60 (15)	N2B—C10B—C9B	113.24 (15)
C16A—C11A—C12A	119.50 (17)	C16B—C11B—C12B	119.69 (17)
C16A—C11A—N2A	117.26 (16)	C16B—C11B—N2B	117.85 (16)
C12A—C11A—N2A	123.23 (17)	C12B—C11B—N2B	122.43 (17)
C13A—C12A—C11A	118.97 (19)	C13B—C12B—C11B	119.14 (19)
C13A—C12A—H12A	120.5	C13B—C12B—H12B	120.4
C11A—C12A—H12A	120.5	C11B—C12B—H12B	120.4
C14A—C13A—C12A	121.7 (2)	C14B—C13B—C12B	121.37 (19)
C14A—C13A—H13A	119.1	C14B—C13B—H13B	119.3
C12A—C13A—H13A	119.1	C12B—C13B—H13B	119.3
C13A—C14A—C15A	118.88 (19)	C13B—C14B—C15B	119.25 (19)
C13A—C14A—H14A	120.6	C13B—C14B—H14B	120.4
C15A—C14A—H14A	120.6	C15B—C14B—H14B	120.4
C16A—C15A—C14A	120.3 (2)	C16B—C15B—C14B	119.96 (19)
C16A—C15A—H15A	119.8	C16B—C15B—H15B	120.0
C14A—C15A—H15A	119.8	C14B—C15B—H15B	120.0
C15A—C16A—C11A	120.60 (18)	C15B—C16B—C11B	120.56 (18)
C15A—C16A—H16A	119.7	C15B—C16B—H16B	119.7
C11A—C16A—H16A	119.7	C11B—C16B—H16B	119.7
O2A—C17A—N1A	125.63 (18)	O2B—C17B—O3B	123.98 (17)
O2A—C17A—O3A	124.19 (18)	O2B—C17B—N1B	125.03 (17)
N1A—C17A—O3A	110.18 (16)	O3B—C17B—N1B	110.99 (15)
O3A—C18A—C19A	107.33 (17)	O3B—C18B—C19B	108.59 (15)
O3A—C18A—H18A	110.2	O3B—C18B—H18C	110.0
C19A—C18A—H18A	110.2	C19B—C18B—H18C	110.0
O3A—C18A—H18B	110.2	O3B—C18B—H18D	110.0
C19A—C18A—H18B	110.2	C19B—C18B—H18D	110.0
H18A—C18A—H18B	108.5	H18C—C18B—H18D	108.4
C24A—C19A—C20A	118.5 (2)	C24B—C19B—C20B	119.29 (19)
C24A—C19A—C18A	121.3 (2)	C24B—C19B—C18B	119.83 (18)
C20A—C19A—C18A	120.2 (2)	C20B—C19B—C18B	120.75 (18)
C21A—C20A—C19A	120.5 (2)	C21B—C20B—C19B	120.3 (2)
C21A—C20A—H20A	119.8	C21B—C20B—H20B	119.8
C19A—C20A—H20A	119.8	C19B—C20B—H20B	119.8
C22A—C21A—C20A	120.4 (2)	C22B—C21B—C20B	120.3 (2)
C22A—C21A—H21A	119.8	C22B—C21B—H21B	119.9
C20A—C21A—H21A	119.8	C20B—C21B—H21B	119.9
C23A—C22A—C21A	119.8 (2)	C21B—C22B—C23B	119.7 (2)
C23A—C22A—H22A	120.1	C21B—C22B—H22B	120.2
C21A—C22A—H22A	120.1	C23B—C22B—H22B	120.2
C22A—C23A—C24A	120.3 (2)	C22B—C23B—C24B	120.1 (2)
C22A—C23A—H23A	119.9	C22B—C23B—H23B	119.9
C24A—C23A—H23A	119.9	C24B—C23B—H23B	119.9
C19A—C24A—C23A	120.7 (2)	C19B—C24B—C23B	120.2 (2)
C19A—C24A—H24A	119.7	C19B—C24B—H24B	119.9
C23A—C24A—H24A	119.7	C23B—C24B—H24B	119.9

C17A—N1A—C1A—C2A	−128.16 (18)	C17B—N1B—C1B—C2B	−126.23 (17)
C9A—N1A—C1A—C2A	50.0 (2)	C9B—N1B—C1B—C2B	41.4 (2)
N1A—C1A—C2A—C7A	−45.8 (2)	N1B—C1B—C2B—C7B	−43.7 (2)
N1A—C1A—C2A—C3A	132.42 (19)	N1B—C1B—C2B—C3B	138.19 (18)
C7A—C2A—C3A—C4A	0.2 (3)	C7B—C2B—C3B—C4B	−0.2 (3)
C1A—C2A—C3A—C4A	−178.02 (19)	C1B—C2B—C3B—C4B	177.83 (18)
C2A—C3A—C4A—C5A	0.3 (3)	C2B—C3B—C4B—C5B	1.1 (3)
C3A—C4A—C5A—C6A	−0.3 (3)	C3B—C4B—C5B—C6B	−0.6 (4)
C4A—C5A—C6A—C7A	−0.2 (3)	C4B—C5B—C6B—C7B	−0.9 (3)
C5A—C6A—C7A—C2A	0.7 (3)	C3B—C2B—C7B—C6B	−1.2 (3)
C5A—C6A—C7A—C8A	−179.92 (17)	C1B—C2B—C7B—C6B	−179.39 (17)
C3A—C2A—C7A—C6A	−0.7 (3)	C3B—C2B—C7B—C8B	177.60 (17)
C1A—C2A—C7A—C6A	177.64 (16)	C1B—C2B—C7B—C8B	−0.6 (2)
C3A—C2A—C7A—C8A	179.90 (16)	C5B—C6B—C7B—C2B	1.8 (3)
C1A—C2A—C7A—C8A	−1.8 (2)	C5B—C6B—C7B—C8B	−176.95 (18)
C6A—C7A—C8A—C9A	−131.58 (18)	C2B—C7B—C8B—C9B	48.4 (2)
C2A—C7A—C8A—C9A	47.8 (2)	C6B—C7B—C8B—C9B	−132.84 (19)
C17A—N1A—C9A—C10A	−67.8 (2)	C17B—N1B—C9B—C10B	−67.7 (2)
C1A—N1A—C9A—C10A	114.07 (17)	C1B—N1B—C9B—C10B	124.96 (16)
C17A—N1A—C9A—C8A	172.49 (16)	C17B—N1B—C9B—C8B	171.73 (15)
C1A—N1A—C9A—C8A	−5.6 (2)	C1B—N1B—C9B—C8B	4.3 (2)
C7A—C8A—C9A—N1A	−42.5 (2)	C7B—C8B—C9B—N1B	−48.7 (2)
C7A—C8A—C9A—C10A	−163.24 (15)	C7B—C8B—C9B—C10B	−170.89 (16)
C11A—N2A—C10A—O1A	−1.8 (3)	C11B—N2B—C10B—O1B	2.6 (3)
C11A—N2A—C10A—C9A	175.61 (16)	C11B—N2B—C10B—C9B	179.40 (16)
N1A—C9A—C10A—O1A	−43.4 (2)	N1B—C9B—C10B—O1B	−47.3 (2)
C8A—C9A—C10A—O1A	77.4 (2)	C8B—C9B—C10B—O1B	74.0 (2)
N1A—C9A—C10A—N2A	139.05 (16)	N1B—C9B—C10B—N2B	135.71 (16)
C8A—C9A—C10A—N2A	−100.12 (18)	C8B—C9B—C10B—N2B	−102.99 (18)
C10A—N2A—C11A—C16A	169.06 (18)	C10B—N2B—C11B—C16B	151.23 (19)
C10A—N2A—C11A—C12A	−12.0 (3)	C10B—N2B—C11B—C12B	−30.9 (3)
C16A—C11A—C12A—C13A	0.1 (3)	C16B—C11B—C12B—C13B	−1.7 (3)
N2A—C11A—C12A—C13A	−178.81 (19)	N2B—C11B—C12B—C13B	−179.6 (2)
C11A—C12A—C13A—C14A	0.3 (4)	C11B—C12B—C13B—C14B	0.8 (4)
C12A—C13A—C14A—C15A	−0.3 (4)	C12B—C13B—C14B—C15B	0.5 (4)
C13A—C14A—C15A—C16A	−0.3 (4)	C13B—C14B—C15B—C16B	−0.9 (3)
C14A—C15A—C16A—C11A	0.8 (3)	C14B—C15B—C16B—C11B	−0.1 (3)
C12A—C11A—C16A—C15A	−0.7 (3)	C12B—C11B—C16B—C15B	1.4 (3)
N2A—C11A—C16A—C15A	178.33 (19)	N2B—C11B—C16B—C15B	179.33 (19)
C9A—N1A—C17A—O2A	−179.46 (17)	C18B—O3B—C17B—O2B	1.7 (2)
C1A—N1A—C17A—O2A	−1.3 (3)	C18B—O3B—C17B—N1B	−178.90 (14)
C9A—N1A—C17A—O3A	0.5 (2)	C9B—N1B—C17B—O2B	−173.78 (17)
C1A—N1A—C17A—O3A	178.60 (15)	C1B—N1B—C17B—O2B	−6.2 (3)
C18A—O3A—C17A—O2A	−4.1 (3)	C9B—N1B—C17B—O3B	6.8 (2)
C18A—O3A—C17A—N1A	175.97 (16)	C1B—N1B—C17B—O3B	174.36 (14)
C17A—O3A—C18A—C19A	−154.89 (17)	C17B—O3B—C18B—C19B	−152.18 (16)
O3A—C18A—C19A—C24A	−126.1 (2)	O3B—C18B—C19B—C24B	−140.1 (2)
O3A—C18A—C19A—C20A	55.3 (3)	O3B—C18B—C19B—C20B	44.1 (3)
C24A—C19A—C20A—C21A	0.1 (4)	C24B—C19B—C20B—C21B	−0.8 (3)
C18A—C19A—C20A—C21A	178.8 (2)	C18B—C19B—C20B—C21B	175.0 (2)
C19A—C20A—C21A—C22A	0.1 (4)	C19B—C20B—C21B—C22B	−0.8 (4)
C20A—C21A—C22A—C23A	−0.1 (4)	C20B—C21B—C22B—C23B	1.1 (4)
C21A—C22A—C23A—C24A	−0.1 (4)	C21B—C22B—C23B—C24B	0.3 (4)
C20A—C19A—C24A—C23A	−0.3 (3)	C20B—C19B—C24B—C23B	2.2 (4)
C18A—C19A—C24A—C23A	−179.0 (2)	C18B—C19B—C24B—C23B	−173.7 (2)
C22A—C23A—C24A—C19A	0.3 (4)	C22B—C23B—C24B—C19B	−1.9 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2A—H2A···O1Bⁱ	0.97 (1)	1.97 (1)	2.9213 (16)	167 (1)
N2B—H2B···O2Bⁱⁱ	0.97 (1)	1.92 (1)	2.8904 (16)	176 (1)

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

Experimental details

Crystal data
Chemical formula	C₂₄H₂₂N₂O₃
M_r	386.44
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	173
a, b, c (Å)	13.0338 (5), 10.8079 (2), 14.0431 (5)
β (°)	92.031 (1)
V (Å³)	1976.98 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.34 × 0.34 × 0.23

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9418, 4958, 4347
R_int	0.014

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.095, 1.15
No. of reflections	4958
No. of parameters	532
No. of restraints	3
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.54, −0.57

Computer programs: COLLECT (Nonius, 2000), DENZO-SMN (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2A—H2A···O1Bⁱ	0.968 (12)	1.971 (13)	2.9213 (16)	166.6 (12)
N2B—H2B···O2Bⁱⁱ	0.969 (12)	1.923 (12)	2.8904 (16)	176.1 (13)

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

Acknowledgements

The authors wish to thank Dr Hong Su of the Chemistry Department of the University of Cape Town for her assistance with the crystallographic data collection.

References

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