Crystal structure of L-tryptophan–fumaric acid–water (1/1/1)

In the title compound, C₁₁H₁₂N₂O₂·C₄H₄O₄·H₂O, the L-tryp­to­phan mol­ecule crystallized as a zwitterion, together with a neutral fumaric acid mol­ecule and a water solvent mol­ecule. In the crystal, the three components are linked by a series of N—H...O, O—H...O and C—H...O hydrogen bonds, forming slabs lying parallel to (001). The slabs are connected by O—H...O hydrogen bonds, involving inversion-related fumaric acid groups, leading to the formation of a three-dimensional structure.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.034
• wR factor = 0.084
• Data-to-parameter ratio = 13.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax < 18) ........       7.14 Note
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....        2.7 Note
PLAT480_ALERT_4_C Long H...A H-Bond Reported H3B    ..  O3      ..       2.66 Ang.
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          2 Report

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          3 Note
PLAT007_ALERT_5_G Number of Unrefined Donor-H Atoms ..............          2 Report
PLAT172_ALERT_4_G The CIF-Embedded .res File Contains DFIX Records          2 Report
PLAT791_ALERT_4_G The Model has Chirality at C2      (Chiral SPGR)          S Verify
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          4 Note
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Th(Min) ...          2 Report

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   6 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Natural aromatic amino acids, particularly tryptophan, have near UV absorption and emission properties which are utilized extensively in solution phase investigations of structure-function relationships (Demchenko, 1986). Fumaric acid is known to exist in two different polymorphic forms viz. cis and trans ( Reis & Schneider, 1928; Yardley, 1925; Bednowitz & Post, 1966).

In conjunction with our ongoing work on non-linear optical organic crystals among the 20 naturally occurring amino acids, we have directed our inter­est to tryptophan (Trp), one of the essential amino acids for humans. The non-linear optical properties of organic molecules and crystals have been reviewed by Zyss (Chemla & Zyss, 1987; Zyss & Ledoux, 1994; Zyss & Nicoud, 1996). For similar properties and most the common confirmations of L-tryptophan have been reported (Bye et al., 1973; Bakke & Mostad, 1980). Compared with other amino acids, there are less than 30 tryptophan structures listed in the Cambridge Structural Database (Groom & Allen, 2014), due to the difficulty of obtaining good optical quality crystals; as noted by (Hubschle et al., 2002) who studied the crystal structure of L-tryptophan formic acid solvate. We successfully obtained good quality hard golden-yellow single crystals of L-tryptophan fumaric acid monohydrate, and we report herein on its synthesis and crystal structure.

In the title compound, Fig. 1, L-tryptophan is zwitterionic, as are most amino acids in the solid state, and fumaric acid is neutral. The bond lengths and angles in L-trypophan and fumaric acid are similar to those reported previously (Gorbitz, 2006; Gorbitz et al., 2012; Goswami et al., 1999).

In the crystal, the three components are linked by a series of O—H···O, N—H···O and C—H···O hydrogen bonds forming slabs lying parallel to (001); Table 1 and Fig. 2. The slabs are connected by O—H···O hydrogen bonds, involving inversion related fumaric acid groups, leading to the formation of a three-dimensional structure; Table 1 and Fig. 3.

S2. Synthesis and crystallization

An aqueous solution of L-tryptophan and fumaric acid in a 1:1 stoichiometric ratio was stirred at room temperature for 6 h. The resulting yellow solution was filtered and kept in a Petri dish. Yellow prismatic-shaped hard crystals suitable for X-ray analysis were obtained over a period of 5 days.

S3. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The N-bound, acid and water H atoms were located in a difference Fourier map. The NH and NH₃ H atoms were freely refined. The water H atoms were refined with distance restraints: O—H = 0.86 (2) Å, H···H = 1.388 (20) Å with U_iso(H) = 1.5U_eq(O). The acid (OH) H atoms and the C-bound H atoms were included in calculated positions and treated as riding atoms: U_iso(H) = 1.5U_eq(O,C) for OH and methyl H atoms and 1.2U_eq(C) for other H atoms.

Related literature

For literature on the UV spectroscopy of proteins, see: Demchenko (1986). For the different polymorphic forms of fumaric acid, see: Reis & Schneider (1928); Yardley (1925); Bednowitz & Post (1966). For the nonlinear optical properties of organic molecules, see: Chemla & Zyss (1987); Zyss & Ledoux (1994); Zyss & Nicoud (1996). For the common conformations of L-tryptophan, see: Bye et al. (1973); Bakke & Mostad (1980). The bond lengths and angles in L-trypophan, see for example: Gorbitz (2006); Gorbitz et al. (2012), and for fumaric acid, see: Goswami et al. (1999). For the crystal structure of L-tryptophan formic acid solvate, see: Hubschle et al. (2002). For details of the Cambridge Structural Database, see: Groom & Allen (2014).

Structure description

Natural aromatic amino acids, particularly tryptophan, have near UV absorption and emission properties which are utilized extensively in solution phase investigations of structure-function relationships (Demchenko, 1986). Fumaric acid is known to exist in two different polymorphic forms viz. cis and trans ( Reis & Schneider, 1928; Yardley, 1925; Bednowitz & Post, 1966).

In conjunction with our ongoing work on non-linear optical organic crystals among the 20 naturally occurring amino acids, we have directed our inter­est to tryptophan (Trp), one of the essential amino acids for humans. The non-linear optical properties of organic molecules and crystals have been reviewed by Zyss (Chemla & Zyss, 1987; Zyss & Ledoux, 1994; Zyss & Nicoud, 1996). For similar properties and most the common confirmations of L-tryptophan have been reported (Bye et al., 1973; Bakke & Mostad, 1980). Compared with other amino acids, there are less than 30 tryptophan structures listed in the Cambridge Structural Database (Groom & Allen, 2014), due to the difficulty of obtaining good optical quality crystals; as noted by (Hubschle et al., 2002) who studied the crystal structure of L-tryptophan formic acid solvate. We successfully obtained good quality hard golden-yellow single crystals of L-tryptophan fumaric acid monohydrate, and we report herein on its synthesis and crystal structure.

In the title compound, Fig. 1, L-tryptophan is zwitterionic, as are most amino acids in the solid state, and fumaric acid is neutral. The bond lengths and angles in L-trypophan and fumaric acid are similar to those reported previously (Gorbitz, 2006; Gorbitz et al., 2012; Goswami et al., 1999).

In the crystal, the three components are linked by a series of O—H···O, N—H···O and C—H···O hydrogen bonds forming slabs lying parallel to (001); Table 1 and Fig. 2. The slabs are connected by O—H···O hydrogen bonds, involving inversion related fumaric acid groups, leading to the formation of a three-dimensional structure; Table 1 and Fig. 3.

For literature on the UV spectroscopy of proteins, see: Demchenko (1986). For the different polymorphic forms of fumaric acid, see: Reis & Schneider (1928); Yardley (1925); Bednowitz & Post (1966). For the nonlinear optical properties of organic molecules, see: Chemla & Zyss (1987); Zyss & Ledoux (1994); Zyss & Nicoud (1996). For the common conformations of L-tryptophan, see: Bye et al. (1973); Bakke & Mostad (1980). The bond lengths and angles in L-trypophan, see for example: Gorbitz (2006); Gorbitz et al. (2012), and for fumaric acid, see: Goswami et al. (1999). For the crystal structure of L-tryptophan formic acid solvate, see: Hubschle et al. (2002). For details of the Cambridge Structural Database, see: Groom & Allen (2014).

Synthesis and crystallization

An aqueous solution of L-tryptophan and fumaric acid in a 1:1 stoichiometric ratio was stirred at room temperature for 6 h. The resulting yellow solution was filtered and kept in a Petri dish. Yellow prismatic-shaped hard crystals suitable for X-ray analysis were obtained over a period of 5 days.

Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 2. The N-bound, acid and water H atoms were located in a difference Fourier map. The NH and NH₃ H atoms were freely refined. The water H atoms were refined with distance restraints: O—H = 0.86 (2) Å, H···H = 1.388 (20) Å with U_iso(H) = 1.5U_eq(O). The acid (OH) H atoms and the C-bound H atoms were included in calculated positions and treated as riding atoms: U_iso(H) = 1.5U_eq(O,C) for OH and methyl H atoms and 1.2U_eq(C) for other H atoms.

Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 40% probability level.
	Fig. 2. The crystal packing of the title compound, viewed along the a axis. The hydrogen bonds are shown as dashed lines (see Table 1 for details).
	Fig. 3. The crystal packing of the title compound, viewed along the b axis. The hydrogen bonds are shown as dashed lines (see Table 1 for details).

L-Tryptophan–fumaric acid–water (1/1/1)

Crystal data

C11H12N2O2·C4H4O4·H2O	F(000) = 712
Mr = 338.31	Dx = 1.392 Mg m^−3
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
a = 11.3928 (8) Å	Cell parameters from 5033 reflections
b = 6.6476 (4) Å	θ = 2.8–27.9°
c = 21.4219 (13) Å	µ = 0.11 mm^−1
β = 95.801 (3)°	T = 296 K
V = 1614.07 (18) Å^3	Block, colourless
Z = 4	0.30 × 0.20 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	2731 reflections with I > 2σ(I)
Radiation source: Sealed X-ray tube	Rint = 0.025
ω and φ scan	θmax = 26.0°, θmin = 2.9°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −14→14
Tmin = 0.898, Tmax = 0.978	k = −8→8
10737 measured reflections	l = −26→26
3157 independent reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.034	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.084	w = 1/[σ^2(Fo^2) + (0.0458P)^2 + 0.2154P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
3157 reflections	Δρmax = 0.18 e Å^−3
242 parameters	Δρmin = −0.15 e Å^−3
4 restraints	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0069 (11)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1	0.75082 (19)	0.1813 (4)	0.77433 (10)	0.0380 (5)
H1	0.825 (3)	0.191 (5)	0.7735 (13)	0.047 (8)*
N2	0.5095 (2)	0.4264 (3)	0.91895 (10)	0.0276 (5)
H2A	0.472 (3)	0.534 (5)	0.9350 (15)	0.056 (10)*
H2B	0.563 (3)	0.476 (5)	0.8921 (14)	0.049 (8)*
H2C	0.554 (3)	0.365 (4)	0.9546 (15)	0.047 (9)*
O1	0.24153 (16)	0.1425 (3)	0.89730 (8)	0.0483 (5)
O2	0.35274 (17)	0.2275 (3)	0.98224 (8)	0.0485 (6)
O3	0.50562 (13)	0.6533 (3)	0.80307 (7)	0.0334 (4)
O4	0.69014 (13)	0.6700 (3)	0.77851 (7)	0.0381 (4)
H4O	0.7050	0.6615	0.8167	0.057*
O5	0.63962 (18)	0.6937 (5)	0.54724 (8)	0.0706 (7)
H5O	0.6080	0.6855	0.5112	0.106*
O6	0.45352 (18)	0.6884 (4)	0.57018 (8)	0.0595 (6)
O7	0.37013 (19)	0.7265 (3)	0.97085 (11)	0.0532 (6)
H7A	0.304 (2)	0.705 (5)	0.9880 (16)	0.080*
H7B	0.382 (3)	0.852 (4)	0.9713 (18)	0.080*
C1	0.3327 (2)	0.2159 (3)	0.92463 (10)	0.0263 (5)
C2	0.4263 (2)	0.2860 (3)	0.88365 (10)	0.0244 (5)
H2	0.3876	0.3556	0.8468	0.029*
C3	0.4928 (2)	0.1034 (4)	0.86179 (12)	0.0328 (6)
H3A	0.5345	0.0401	0.8983	0.039*
H3B	0.4354	0.0073	0.8432	0.039*
C4	0.5792 (2)	0.1458 (4)	0.81563 (11)	0.0302 (5)
C5	0.6979 (2)	0.1602 (4)	0.82805 (11)	0.0357 (6)
H5	0.7379	0.1562	0.8681	0.043*
C6	0.6657 (2)	0.1816 (4)	0.72436 (11)	0.0333 (6)
C7	0.6742 (2)	0.1930 (5)	0.66020 (12)	0.0445 (7)
H7	0.7471	0.2041	0.6445	0.053*
C8	0.5720 (3)	0.1874 (5)	0.62093 (12)	0.0508 (7)
H8	0.5756	0.1951	0.5778	0.061*
C9	0.4630 (2)	0.1705 (5)	0.64405 (13)	0.0507 (7)
H9	0.3951	0.1677	0.6160	0.061*
C10	0.4529 (2)	0.1579 (5)	0.70688 (11)	0.0417 (6)
H10	0.3792	0.1472	0.7216	0.050*
C11	0.5557 (2)	0.1615 (4)	0.74880 (11)	0.0312 (5)
C13	0.57628 (19)	0.6648 (4)	0.76415 (10)	0.0286 (5)
C14	0.5377 (2)	0.6733 (4)	0.69680 (10)	0.0365 (6)
H14	0.4570	0.6672	0.6848	0.044*
C15	0.6070 (2)	0.6888 (5)	0.65258 (11)	0.0418 (7)
H15	0.6880	0.6994	0.6632	0.050*
C16	0.5603 (2)	0.6899 (5)	0.58582 (11)	0.0447 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0245 (11)	0.0520 (14)	0.0381 (12)	0.0037 (12)	0.0067 (9)	−0.0028 (12)
N2	0.0274 (12)	0.0345 (12)	0.0219 (11)	−0.0020 (9)	0.0072 (9)	0.0000 (9)
O1	0.0374 (11)	0.0818 (15)	0.0254 (9)	−0.0268 (11)	0.0019 (7)	−0.0006 (10)
O2	0.0441 (11)	0.0834 (16)	0.0183 (9)	−0.0273 (11)	0.0045 (7)	−0.0019 (9)
O3	0.0300 (9)	0.0449 (10)	0.0260 (8)	−0.0024 (9)	0.0056 (7)	0.0031 (8)
O4	0.0278 (9)	0.0651 (11)	0.0216 (8)	−0.0034 (10)	0.0026 (6)	0.0003 (10)
O5	0.0548 (13)	0.133 (2)	0.0237 (9)	−0.0004 (17)	0.0058 (9)	−0.0012 (15)
O6	0.0464 (12)	0.1044 (17)	0.0265 (9)	0.0027 (13)	−0.0027 (8)	0.0012 (12)
O7	0.0511 (13)	0.0543 (13)	0.0578 (13)	0.0096 (11)	0.0227 (10)	0.0010 (11)
C1	0.0249 (12)	0.0323 (13)	0.0220 (11)	−0.0021 (10)	0.0034 (10)	−0.0003 (10)
C2	0.0250 (13)	0.0331 (12)	0.0149 (11)	0.0015 (10)	0.0011 (9)	0.0015 (9)
C3	0.0399 (15)	0.0318 (13)	0.0275 (13)	0.0034 (11)	0.0073 (12)	−0.0007 (10)
C4	0.0304 (12)	0.0315 (12)	0.0295 (12)	0.0041 (12)	0.0074 (9)	−0.0047 (11)
C5	0.0371 (14)	0.0387 (13)	0.0312 (13)	0.0068 (13)	0.0029 (10)	−0.0028 (12)
C6	0.0327 (13)	0.0365 (13)	0.0317 (12)	0.0040 (12)	0.0076 (10)	−0.0033 (12)
C7	0.0416 (15)	0.0558 (17)	0.0384 (14)	0.0055 (15)	0.0158 (12)	−0.0013 (14)
C8	0.0600 (19)	0.0640 (19)	0.0291 (13)	0.0095 (18)	0.0084 (13)	0.0003 (15)
C9	0.0446 (16)	0.0678 (19)	0.0374 (14)	0.0066 (17)	−0.0071 (12)	−0.0061 (16)
C10	0.0301 (13)	0.0578 (16)	0.0373 (14)	0.0054 (15)	0.0033 (11)	−0.0047 (15)
C11	0.0286 (12)	0.0331 (12)	0.0323 (12)	0.0049 (12)	0.0056 (9)	−0.0043 (12)
C13	0.0286 (12)	0.0313 (12)	0.0257 (11)	−0.0016 (12)	0.0024 (9)	0.0003 (11)
C14	0.0328 (13)	0.0500 (15)	0.0263 (12)	−0.0002 (14)	0.0002 (10)	−0.0013 (14)
C15	0.0339 (14)	0.0630 (18)	0.0278 (13)	0.0024 (15)	−0.0002 (11)	−0.0004 (14)
C16	0.0429 (16)	0.0637 (19)	0.0279 (13)	0.0031 (16)	0.0053 (11)	−0.0018 (15)

Geometric parameters (Å, º)

N1—C5	1.359 (3)	C3—H3A	0.9700
N1—C6	1.370 (3)	C3—H3B	0.9700
N1—H1	0.85 (3)	C4—C5	1.355 (3)
N2—C2	1.482 (3)	C4—C11	1.433 (3)
N2—H2A	0.92 (4)	C5—H5	0.9300
N2—H2B	0.94 (3)	C6—C7	1.390 (3)
N2—H2C	0.96 (3)	C6—C11	1.413 (3)
O1—C1	1.240 (3)	C7—C8	1.366 (4)
O2—C1	1.235 (3)	C7—H7	0.9300
O3—C13	1.219 (3)	C8—C9	1.387 (4)
O4—C13	1.303 (3)	C8—H8	0.9300
O4—H4O	0.8200	C9—C10	1.365 (4)
O5—C16	1.285 (3)	C9—H9	0.9300
O5—H5O	0.8200	C10—C11	1.401 (3)
O6—C16	1.229 (3)	C10—H10	0.9300
O7—H7A	0.88 (2)	C13—C14	1.466 (3)
O7—H7B	0.85 (2)	C14—C15	1.297 (3)
C1—C2	1.521 (3)	C14—H14	0.9300
C2—C3	1.529 (3)	C15—C16	1.475 (3)
C2—H2	0.9800	C15—H15	0.9300
C3—C4	1.491 (3)
C5—N1—C6	108.8 (2)	N1—C5—H5	124.4
C5—N1—H1	123.6 (19)	N1—C6—C7	131.2 (2)
C6—N1—H1	127.6 (19)	N1—C6—C11	107.1 (2)
C2—N2—H2A	113 (2)	C7—C6—C11	121.7 (2)
C2—N2—H2B	109.4 (19)	C8—C7—C6	117.9 (2)
H2A—N2—H2B	108 (3)	C8—C7—H7	121.1
C2—N2—H2C	113.4 (17)	C6—C7—H7	121.1
H2A—N2—H2C	105 (2)	C7—C8—C9	121.4 (2)
H2B—N2—H2C	108 (2)	C7—C8—H8	119.3
C13—O4—H4O	109.5	C9—C8—H8	119.3
C16—O5—H5O	109.5	C10—C9—C8	121.6 (3)
H7A—O7—H7B	107 (3)	C10—C9—H9	119.2
O2—C1—O1	123.9 (2)	C8—C9—H9	119.2
O2—C1—C2	119.2 (2)	C9—C10—C11	118.9 (2)
O1—C1—C2	116.79 (19)	C9—C10—H10	120.6
N2—C2—C1	110.35 (18)	C11—C10—H10	120.6
N2—C2—C3	110.2 (2)	C10—C11—C6	118.6 (2)
C1—C2—C3	109.37 (19)	C10—C11—C4	134.3 (2)
N2—C2—H2	109.0	C6—C11—C4	107.1 (2)
C1—C2—H2	109.0	O3—C13—O4	123.4 (2)
C3—C2—H2	109.0	O3—C13—C14	121.5 (2)
C4—C3—C2	115.7 (2)	O4—C13—C14	115.07 (19)
C4—C3—H3A	108.4	C15—C14—C13	125.3 (2)
C2—C3—H3A	108.4	C15—C14—H14	117.4
C4—C3—H3B	108.4	C13—C14—H14	117.4
C2—C3—H3B	108.4	C14—C15—C16	121.5 (2)
H3A—C3—H3B	107.4	C14—C15—H15	119.3
C5—C4—C11	105.8 (2)	C16—C15—H15	119.3
C5—C4—C3	126.6 (2)	O6—C16—O5	124.5 (2)
C11—C4—C3	127.4 (2)	O6—C16—C15	121.0 (2)
C4—C5—N1	111.1 (2)	O5—C16—C15	114.6 (2)
C4—C5—H5	124.4
O2—C1—C2—N2	−21.1 (3)	C8—C9—C10—C11	−0.3 (5)
O1—C1—C2—N2	161.6 (2)	C9—C10—C11—C6	1.1 (4)
O2—C1—C2—C3	100.3 (3)	C9—C10—C11—C4	−177.8 (3)
O1—C1—C2—C3	−77.0 (3)	N1—C6—C11—C10	179.9 (3)
N2—C2—C3—C4	−64.7 (3)	C7—C6—C11—C10	−1.5 (4)
C1—C2—C3—C4	173.8 (2)	N1—C6—C11—C4	−0.9 (3)
C2—C3—C4—C5	101.2 (3)	C7—C6—C11—C4	177.6 (3)
C2—C3—C4—C11	−84.9 (3)	C5—C4—C11—C10	180.0 (3)
C11—C4—C5—N1	−0.7 (3)	C3—C4—C11—C10	5.1 (5)
C3—C4—C5—N1	174.2 (2)	C5—C4—C11—C6	1.0 (3)
C6—N1—C5—C4	0.1 (3)	C3—C4—C11—C6	−173.9 (2)
C5—N1—C6—C7	−177.9 (3)	O3—C13—C14—C15	178.9 (3)
C5—N1—C6—C11	0.5 (3)	O4—C13—C14—C15	−1.3 (4)
N1—C6—C7—C8	179.2 (3)	C13—C14—C15—C16	178.1 (3)
C11—C6—C7—C8	1.0 (4)	C14—C15—C16—O6	4.4 (5)
C6—C7—C8—C9	−0.1 (5)	C14—C15—C16—O5	−175.9 (3)
C7—C8—C9—C10	−0.3 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O3^i	0.85 (3)	2.11 (3)	2.912 (3)	158 (3)
N2—H2A···O7	0.92 (4)	1.94 (4)	2.845 (3)	170 (3)
N2—H2B···O1^ii	0.94 (3)	2.30 (3)	3.085 (3)	140 (2)
N2—H2B···O3	0.94 (3)	2.28 (3)	2.901 (3)	123 (2)
N2—H2C···O2^iii	0.96 (3)	1.87 (3)	2.832 (3)	174 (3)
O4—H4O···O1^ii	0.82	1.74	2.559 (2)	178
O5—H5O···O6^iv	0.82	1.81	2.630 (3)	174
O7—H7A···O1^v	0.88 (2)	2.60 (3)	3.261 (3)	133 (3)
O7—H7A···O2^v	0.88 (2)	1.97 (2)	2.824 (3)	165 (3)
O7—H7B···O2^vi	0.85 (2)	2.53 (3)	3.347 (3)	162 (3)
C3—H3B···O3^vii	0.97	2.66	3.255 (3)	120
C5—H5···O7^i	0.93	2.58	3.491 (3)	166

Symmetry codes: (i) x+1/2, y−1/2, z; (ii) x+1/2, y+1/2, z; (iii) −x+1, y, −z+2; (iv) −x+1, y, −z+1; (v) −x+1/2, y+1/2, −z+2; (vi) x, y+1, z; (vii) x, y−1, z.