Di­phenyl­alanine in tetra­hydro­furan: a highly potent candidate for the development of novel nanomaterials

The peptide di-L-phenyl­alanine (FF) has emerged as a highly potent candidate for the development of novel nanomaterials. The unprotected peptide was dissolved in 1,1,1,3,3,3-hexa­fluoro­propan-2-ol (HFIP) mixed with tetra­hydro­furan (THF) and single crystals of the THF monosolvate, C₁₈H₂₀N₂O₃·C₄H₈O, were grown by slow evaporation in a `vial-in-closed-bottle' system. THF is a mol­ecule that can only act as a hydrogen-bond acceptor. Thus, the hydrogen-bond patterns observed in the crystal structures at 100 and 299 K are different compared to that of crystals grown from water and methanol [Mason et al. (2014). ACS Nano. 8, 1243–1253].

Computing details

For both structures, data collection: PROTEUM2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS86 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015). Molecular graphics: COOT (Emsley et al., 2010) and SwissPDBViewer (Guex & Peitsch, 1997) for temperature_100K; COOT (Emsley et al., 2010), SwissPDBViewer (Guex & Peitsch, 1997) for 299K. Software used to prepare material for publication: CHEMDRAW (Mills, 2006), ORTEPIII (Burnett & Johnson, (1996), ORTEP-3 (Farrugia, 2012) and POV-RAY (Persistence of Vision Pty, 2004) for temperature_100K; CHEMDRAW (Mills, 2006), ORTEP-III (Burnett & Johnson, (1996), ORTEP-3 (Farrugia, 2012), POVRAY (Persistence of Vision, 2004) for 299K.

2-(2-Azaniumyl-3-phenylpropanamido)-3-phenylpropanoate tetrahydrofuran monosolvate (temperature_100K)

Crystal data

C18H20N2O3·C4H8O	Dx = 1.279 Mg m^−3
Mr = 384.46	Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, P212121	Cell parameters from 19950 reflections
a = 5.0591 (3) Å	θ = 3.2–75.0°
b = 16.7533 (9) Å	µ = 0.71 mm^−1
c = 23.5587 (13) Å	T = 100 K
V = 1996.76 (19) Å^3	Needle, colourless
Z = 4	0.2 × 0.02 × 0.02 mm
F(000) = 824

Data collection

Bruker D8 Venture diffractometer	3882 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube IµS	Rint = 0.037
ω and φ scans	θmax = 75.0°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −6→5
Tmin = 0.867, Tmax = 1.0	k = −20→20
19950 measured reflections	l = −29→29
3983 independent reflections

Refinement

Refinement on F^2	Hydrogen site location: difference Fourier map
Least-squares matrix: full	All H-atom parameters refined
R[F^2 > 2σ(F^2)] = 0.040	w = 1/[σ^2(Fo^2) + (0.0811P)^2 + 0.8254P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.132	(Δ/σ)max < 0.001
S = 1.09	Δρmax = 0.33 e Å^−3
3983 reflections	Δρmin = −0.52 e Å^−3
365 parameters	Absolute structure: Flack x determined using 1558 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
0 restraints	Absolute structure parameter: 0.01 (7)

Special details

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.

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

	x	y	z	Uiso*/Ueq
N_1	0.7011 (5)	0.41181 (13)	0.25508 (10)	0.0247 (5)
H1_1	0.634 (9)	0.418 (2)	0.2181 (17)	0.037 (10)*
H2_1	0.554 (8)	0.4204 (19)	0.2785 (15)	0.028 (8)*
H3_1	0.802 (9)	0.456 (2)	0.2611 (17)	0.038 (10)*
CA_1	0.8469 (5)	0.33605 (16)	0.26229 (10)	0.0215 (5)
HA_1	1.003 (6)	0.3416 (16)	0.2395 (12)	0.014 (7)*
CB_1	0.9363 (6)	0.32392 (19)	0.32407 (11)	0.0264 (6)
HB1_1	1.031 (8)	0.369 (2)	0.3360 (15)	0.031 (9)*
HB2_1	1.036 (8)	0.281 (2)	0.3250 (14)	0.028 (8)*
CG_1	0.7140 (5)	0.31192 (16)	0.36657 (10)	0.0219 (5)
CD1_1	0.6224 (6)	0.37571 (17)	0.39916 (11)	0.0295 (6)
HD1_1	0.696 (8)	0.428 (2)	0.3942 (15)	0.032 (9)*
CD2_1	0.6024 (6)	0.23730 (16)	0.37516 (11)	0.0262 (6)
HD2_1	0.670 (7)	0.1918 (19)	0.3535 (14)	0.025 (8)*
CE1_1	0.4255 (7)	0.36407 (19)	0.43950 (12)	0.0348 (7)
HE1_1	0.354 (9)	0.410 (2)	0.4629 (17)	0.042 (11)*
CE2_1	0.4023 (7)	0.22617 (19)	0.41503 (12)	0.0334 (7)
HE2_1	0.335 (8)	0.176 (2)	0.4227 (14)	0.027 (8)*
CZ_1	0.3156 (6)	0.2894 (2)	0.44738 (12)	0.0342 (7)
HZ_1	0.178 (8)	0.2818 (19)	0.4762 (15)	0.025 (8)*
C_1	0.6746 (5)	0.26717 (14)	0.24147 (9)	0.0178 (5)
O_1	0.4328 (3)	0.27467 (10)	0.23738 (7)	0.0204 (4)
N_2	0.8062 (5)	0.20008 (13)	0.22992 (9)	0.0205 (4)
H1_2	0.976 (9)	0.198 (2)	0.2355 (15)	0.032 (9)*
CA_2	0.6691 (5)	0.12561 (15)	0.21594 (11)	0.0211 (5)
HA_2	0.521 (7)	0.1211 (18)	0.2428 (13)	0.020 (7)*
CB_2	0.5643 (5)	0.12544 (16)	0.15474 (11)	0.0232 (5)
HB1_2	0.426 (8)	0.172 (2)	0.1526 (15)	0.035 (9)*
HB2_2	0.464 (8)	0.077 (2)	0.1477 (14)	0.030 (9)*
CG_2	0.7777 (5)	0.13022 (15)	0.10992 (10)	0.0202 (5)
CD1_2	0.8903 (6)	0.06088 (16)	0.08756 (11)	0.0261 (6)
HD1_2	0.819 (7)	0.011 (2)	0.0981 (14)	0.025 (8)*
CD2_2	0.8706 (5)	0.20353 (16)	0.09002 (11)	0.0236 (6)
HD2_2	0.795 (8)	0.252 (2)	0.1040 (15)	0.030 (9)*
CE1_2	1.0834 (7)	0.06497 (17)	0.04618 (11)	0.0296 (6)
HE1_2	1.158 (8)	0.015 (2)	0.0326 (15)	0.033 (9)*
CE2_2	1.0649 (6)	0.20758 (16)	0.04853 (11)	0.0260 (6)
HE2_2	1.130 (8)	0.259 (2)	0.0346 (16)	0.036 (10)*
CZ_2	1.1738 (6)	0.13813 (18)	0.02669 (11)	0.0268 (6)
HZ_2	1.306 (9)	0.140 (2)	−0.0019 (15)	0.036 (9)*
C_2	0.8528 (6)	0.05438 (17)	0.22780 (13)	0.0303 (6)
O1_2	1.0761 (4)	0.06787 (15)	0.24732 (14)	0.0531 (8)
O2_2	0.7655 (5)	−0.01370 (13)	0.21644 (10)	0.0408 (6)
O1_3	0.5411 (5)	0.43110 (12)	0.14131 (8)	0.0319 (5)
C2_3	0.4997 (7)	0.51361 (19)	0.12622 (15)	0.0349 (7)
H21_3	0.602 (8)	0.530 (2)	0.0883 (15)	0.032 (9)*
H22_3	0.565 (8)	0.543 (2)	0.1581 (16)	0.033 (9)*
C3_3	0.2088 (8)	0.5202 (2)	0.11332 (18)	0.0453 (9)
H31_3	0.096 (11)	0.527 (3)	0.151 (2)	0.061 (13)*
H32_3	0.176 (12)	0.567 (3)	0.088 (2)	0.068 (15)*
C4_3	0.1529 (7)	0.4396 (2)	0.08492 (14)	0.0361 (7)
H41_3	0.199 (8)	0.441 (2)	0.0433 (16)	0.034 (9)*
H42_3	−0.036 (11)	0.422 (3)	0.0910 (18)	0.050 (12)*
C5_3	0.3320 (8)	0.3832 (2)	0.11731 (14)	0.0392 (7)
H51_3	0.238 (10)	0.360 (3)	0.147 (2)	0.057 (13)*
H52_3	0.432 (13)	0.340 (3)	0.088 (2)	0.079 (16)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N_1	0.0286 (12)	0.0240 (11)	0.0213 (10)	−0.0093 (9)	−0.0023 (10)	−0.0016 (8)
CA_1	0.0117 (11)	0.0348 (13)	0.0180 (11)	−0.0019 (10)	−0.0004 (9)	0.0005 (9)
CB_1	0.0150 (11)	0.0443 (16)	0.0199 (12)	−0.0024 (12)	−0.0036 (10)	−0.0005 (11)
CG_1	0.0188 (12)	0.0318 (13)	0.0152 (11)	0.0007 (10)	−0.0055 (9)	0.0015 (9)
CD1_1	0.0383 (17)	0.0285 (13)	0.0216 (12)	0.0024 (12)	−0.0015 (11)	−0.0004 (10)
CD2_1	0.0296 (15)	0.0266 (13)	0.0224 (12)	0.0035 (11)	−0.0032 (11)	0.0025 (10)
CE1_1	0.0419 (17)	0.0408 (16)	0.0217 (12)	0.0146 (15)	0.0039 (12)	0.0011 (11)
CE2_1	0.0385 (17)	0.0354 (15)	0.0264 (13)	−0.0099 (13)	−0.0015 (12)	0.0109 (11)
CZ_1	0.0230 (14)	0.0581 (19)	0.0214 (12)	0.0061 (14)	0.0034 (11)	0.0140 (13)
C_1	0.0141 (10)	0.0261 (11)	0.0131 (10)	0.0017 (9)	0.0012 (9)	0.0006 (8)
O_1	0.0115 (8)	0.0241 (8)	0.0254 (8)	0.0023 (7)	−0.0007 (7)	−0.0018 (7)
N_2	0.0135 (10)	0.0289 (11)	0.0192 (9)	0.0064 (8)	0.0019 (8)	0.0012 (8)
CA_2	0.0167 (11)	0.0242 (12)	0.0224 (11)	0.0052 (10)	0.0052 (10)	0.0025 (9)
CB_2	0.0188 (12)	0.0254 (12)	0.0253 (12)	0.0023 (11)	−0.0003 (10)	0.0005 (9)
CG_2	0.0182 (12)	0.0257 (12)	0.0166 (11)	0.0019 (10)	−0.0046 (9)	−0.0017 (9)
CD1_2	0.0329 (16)	0.0234 (12)	0.0218 (12)	0.0000 (11)	−0.0039 (11)	−0.0006 (9)
CD2_2	0.0231 (14)	0.0255 (12)	0.0223 (12)	0.0038 (10)	−0.0011 (10)	0.0010 (9)
CE1_2	0.0400 (17)	0.0272 (12)	0.0216 (12)	0.0090 (13)	−0.0010 (11)	−0.0040 (10)
CE2_2	0.0294 (14)	0.0269 (13)	0.0218 (12)	−0.0010 (12)	0.0003 (11)	0.0041 (10)
CZ_2	0.0269 (13)	0.0373 (14)	0.0161 (11)	0.0046 (12)	0.0010 (10)	0.0012 (10)
C_2	0.0247 (14)	0.0315 (14)	0.0347 (14)	0.0106 (11)	0.0142 (11)	0.0139 (11)
O1_2	0.0191 (10)	0.0442 (12)	0.096 (2)	0.0045 (9)	0.0019 (12)	0.0399 (14)
O2_2	0.0540 (15)	0.0259 (10)	0.0424 (12)	0.0108 (10)	0.0130 (11)	0.0048 (9)
O1_3	0.0323 (11)	0.0333 (10)	0.0302 (10)	−0.0043 (9)	−0.0078 (9)	0.0008 (8)
C2_3	0.0332 (17)	0.0303 (14)	0.0411 (16)	−0.0005 (12)	−0.0082 (13)	−0.0008 (13)
C3_3	0.0332 (18)	0.0443 (19)	0.058 (2)	0.0050 (15)	−0.0086 (17)	−0.0148 (16)
C4_3	0.0275 (15)	0.0455 (17)	0.0352 (16)	−0.0025 (13)	−0.0022 (13)	−0.0093 (13)
C5_3	0.0461 (19)	0.0385 (16)	0.0332 (15)	−0.0135 (15)	−0.0089 (15)	0.0000 (12)

Geometric parameters (Å, º)

N_1—CA_1	1.478 (3)	CB_2—HB1_2	1.05 (4)
N_1—H1_1	0.94 (4)	CB_2—HB2_2	0.98 (4)
N_1—H2_1	0.94 (4)	CG_2—CD2_2	1.396 (4)
N_1—H3_1	0.90 (4)	CG_2—CD1_2	1.397 (4)
CA_1—C_1	1.527 (3)	CD1_2—CE1_2	1.382 (4)
CA_1—CB_1	1.538 (3)	CD1_2—HD1_2	0.94 (3)
CA_1—HA_1	0.96 (3)	CD2_2—CE2_2	1.388 (4)
CB_1—CG_1	1.519 (4)	CD2_2—HD2_2	0.95 (4)
CB_1—HB1_1	0.94 (4)	CE1_2—CZ_2	1.387 (4)
CB_1—HB2_1	0.88 (4)	CE1_2—HE1_2	0.97 (4)
CG_1—CD2_1	1.387 (4)	CE2_2—CZ_2	1.386 (4)
CG_1—CD1_1	1.395 (4)	CE2_2—HE2_2	0.97 (4)
CD1_1—CE1_1	1.390 (4)	CZ_2—HZ_2	0.95 (4)
CD1_1—HD1_1	0.96 (4)	C_2—O1_2	1.240 (4)
CD2_1—CE2_1	1.393 (4)	C_2—O2_2	1.252 (4)
CD2_1—HD2_1	0.98 (3)	O1_3—C5_3	1.443 (4)
CE1_1—CZ_1	1.381 (5)	O1_3—C2_3	1.443 (4)
CE1_1—HE1_1	1.02 (4)	C2_3—C3_3	1.507 (5)
CE2_1—CZ_1	1.377 (5)	C2_3—H21_3	1.07 (4)
CE2_1—HE2_1	0.93 (4)	C2_3—H22_3	0.96 (4)
CZ_1—HZ_1	0.98 (4)	C3_3—C4_3	1.534 (5)
C_1—O_1	1.233 (3)	C3_3—H31_3	1.06 (5)
C_1—N_2	1.335 (3)	C3_3—H32_3	1.00 (5)
N_2—CA_2	1.465 (3)	C4_3—C5_3	1.515 (5)
N_2—H1_2	0.87 (4)	C4_3—H41_3	1.01 (4)
CA_2—CB_2	1.536 (3)	C4_3—H42_3	1.01 (5)
CA_2—C_2	1.538 (3)	C5_3—H51_3	0.93 (5)
CA_2—HA_2	0.99 (3)	C5_3—H52_3	1.12 (6)
CB_2—CG_2	1.512 (4)
CA_1—N_1—H1_1	113 (2)	CA_2—CB_2—HB1_2	106 (2)
CA_1—N_1—H2_1	117 (2)	CG_2—CB_2—HB2_2	107 (2)
H1_1—N_1—H2_1	104 (3)	CA_2—CB_2—HB2_2	110 (2)
CA_1—N_1—H3_1	114 (3)	HB1_2—CB_2—HB2_2	105 (3)
H1_1—N_1—H3_1	104 (3)	CD2_2—CG_2—CD1_2	117.9 (2)
H2_1—N_1—H3_1	103 (3)	CD2_2—CG_2—CB_2	121.4 (2)
N_1—CA_1—C_1	109.1 (2)	CD1_2—CG_2—CB_2	120.7 (2)
N_1—CA_1—CB_1	111.7 (2)	CE1_2—CD1_2—CG_2	120.9 (3)
C_1—CA_1—CB_1	111.9 (2)	CE1_2—CD1_2—HD1_2	120 (2)
N_1—CA_1—HA_1	105.2 (17)	CG_2—CD1_2—HD1_2	119 (2)
C_1—CA_1—HA_1	111.3 (17)	CE2_2—CD2_2—CG_2	121.2 (2)
CB_1—CA_1—HA_1	107.6 (17)	CE2_2—CD2_2—HD2_2	119 (2)
CG_1—CB_1—CA_1	115.1 (2)	CG_2—CD2_2—HD2_2	120 (2)
CG_1—CB_1—HB1_1	107 (2)	CD1_2—CE1_2—CZ_2	120.7 (3)
CA_1—CB_1—HB1_1	109 (2)	CD1_2—CE1_2—HE1_2	118 (2)
CG_1—CB_1—HB2_1	108 (2)	CZ_2—CE1_2—HE1_2	122 (2)
CA_1—CB_1—HB2_1	108 (2)	CZ_2—CE2_2—CD2_2	120.1 (2)
HB1_1—CB_1—HB2_1	111 (3)	CZ_2—CE2_2—HE2_2	119 (2)
CD2_1—CG_1—CD1_1	118.4 (3)	CD2_2—CE2_2—HE2_2	121 (2)
CD2_1—CG_1—CB_1	121.1 (2)	CE1_2—CZ_2—CE2_2	119.2 (3)
CD1_1—CG_1—CB_1	120.5 (3)	CE1_2—CZ_2—HZ_2	120 (2)
CE1_1—CD1_1—CG_1	120.4 (3)	CE2_2—CZ_2—HZ_2	121 (2)
CE1_1—CD1_1—HD1_1	119 (2)	O1_2—C_2—O2_2	124.5 (3)
CG_1—CD1_1—HD1_1	120 (2)	O1_2—C_2—CA_2	118.4 (3)
CG_1—CD2_1—CE2_1	121.0 (3)	O2_2—C_2—CA_2	117.0 (3)
CG_1—CD2_1—HD2_1	119 (2)	C5_3—O1_3—C2_3	109.2 (2)
CE2_1—CD2_1—HD2_1	120 (2)	O1_3—C2_3—C3_3	105.2 (3)
CZ_1—CE1_1—CD1_1	120.5 (3)	O1_3—C2_3—H21_3	112 (2)
CZ_1—CE1_1—HE1_1	118 (2)	C3_3—C2_3—H21_3	107 (2)
CD1_1—CE1_1—HE1_1	121 (2)	O1_3—C2_3—H22_3	105 (2)
CZ_1—CE2_1—CD2_1	120.1 (3)	C3_3—C2_3—H22_3	117 (2)
CZ_1—CE2_1—HE2_1	118 (2)	H21_3—C2_3—H22_3	111 (3)
CD2_1—CE2_1—HE2_1	121 (2)	C2_3—C3_3—C4_3	101.8 (3)
CE2_1—CZ_1—CE1_1	119.6 (3)	C2_3—C3_3—H31_3	111 (3)
CE2_1—CZ_1—HZ_1	120.6 (19)	C4_3—C3_3—H31_3	111 (3)
CE1_1—CZ_1—HZ_1	119.8 (19)	C2_3—C3_3—H32_3	110 (4)
O_1—C_1—N_2	124.4 (2)	C4_3—C3_3—H32_3	114 (3)
O_1—C_1—CA_1	120.9 (2)	H31_3—C3_3—H32_3	109 (4)
N_2—C_1—CA_1	114.6 (2)	C5_3—C4_3—C3_3	102.6 (3)
C_1—N_2—CA_2	121.8 (2)	C5_3—C4_3—H41_3	112 (2)
C_1—N_2—H1_2	119 (2)	C3_3—C4_3—H41_3	111 (2)
CA_2—N_2—H1_2	118 (2)	C5_3—C4_3—H42_3	108 (3)
N_2—CA_2—CB_2	112.1 (2)	C3_3—C4_3—H42_3	112 (2)
N_2—CA_2—C_2	109.5 (2)	H41_3—C4_3—H42_3	111 (4)
CB_2—CA_2—C_2	112.2 (2)	O1_3—C5_3—C4_3	106.8 (3)
N_2—CA_2—HA_2	106.4 (18)	O1_3—C5_3—H51_3	108 (3)
CB_2—CA_2—HA_2	109.9 (19)	C4_3—C5_3—H51_3	109 (3)
C_2—CA_2—HA_2	106.5 (18)	O1_3—C5_3—H52_3	106 (3)
CG_2—CB_2—CA_2	114.1 (2)	C4_3—C5_3—H52_3	111 (3)
CG_2—CB_2—HB1_2	114 (2)	H51_3—C5_3—H52_3	115 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N_1—H1_1···O1_3	0.94 (4)	1.88 (4)	2.819 (3)	173 (4)
N_2—H1_2···O_1^i	0.87 (4)	2.64 (4)	3.412 (3)	148 (3)
N_1—H2_1···O2_2^ii	0.94 (4)	1.96 (4)	2.753 (4)	141 (3)
N_1—H3_1···O1_2^iii	0.90 (4)	1.99 (4)	2.848 (3)	158 (4)
N_1—H3_1···O2_2^iii	0.90 (4)	2.31 (4)	3.047 (3)	139 (4)

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

2-(2-Azaniumyl-3-phenylpropanamido)-3-phenylpropanoate tetrahydrofuran monosolvate (299K)

Crystal data

C18H20N2O3·C4H8O	Dx = 1.244 Mg m^−3
Mr = 384.46	Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, P212121	Cell parameters from 10537 reflections
a = 5.0827 (3) Å	θ = 3.2–60.4°
b = 16.7903 (9) Å	µ = 0.69 mm^−1
c = 24.0532 (12) Å	T = 299 K
V = 2052.70 (19) Å^3	Needle, colorless
Z = 4	0.2 × 0.02 × 0.02 mm
F(000) = 824

Data collection

Bruker AXS D8 Venture diffractometer	2526 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube IµS	Rint = 0.064
ω– and φ–scans	θmax = 60.4°, θmin = 3.2°
Absorption correction: multi-scan SADABS (Bruker, 2008)	h = −5→5
Tmin = 0.770, Tmax = 1.0	k = −18→15
10537 measured reflections	l = −23→26
2770 independent reflections

Refinement

Refinement on F^2	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.067	w = 1/[σ^2(Fo^2) + (0.0971P)^2 + 1.4119P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.189	(Δ/σ)max = 0.010
S = 1.05	Δρmax = 0.25 e Å^−3
2770 reflections	Δρmin = −0.18 e Å^−3
287 parameters	Absolute structure: Flack x determined using 966 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
0 restraints	Absolute structure parameter: 0.3 (3)

Special details

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.

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

	x	y	z	Uiso*/Ueq
N_1	0.2946 (9)	0.5927 (3)	0.2567 (2)	0.0563 (12)
H3_1	0.181 (13)	0.536 (4)	0.266 (3)	0.082 (18)*
H2_1	0.478 (14)	0.583 (3)	0.275 (3)	0.072 (17)*
H1_1	0.359 (12)	0.591 (3)	0.226 (3)	0.050 (17)*
CA_1	0.1499 (9)	0.6689 (3)	0.2636 (2)	0.0515 (13)
HA_1	−0.0072	0.6666	0.2400	0.049 (13)*
CB_1	0.0599 (11)	0.6806 (4)	0.3231 (2)	0.0601 (14)
HB2_1	−0.0523	0.7273	0.3245	0.060 (16)*
HB1_1	−0.0467	0.6352	0.3337	0.075 (18)*
CG_1	0.2725 (11)	0.6905 (3)	0.3656 (2)	0.0579 (14)
CD1_1	0.3594 (16)	0.6268 (4)	0.3973 (3)	0.082 (2)
HD1_1	0.2873	0.5765	0.3916	0.08 (2)*
CD2_1	0.3893 (14)	0.7632 (4)	0.3755 (3)	0.0747 (18)
HD2_1	0.3379	0.8074	0.3549	0.09 (2)*
CE1_1	0.5522 (18)	0.6370 (6)	0.4374 (3)	0.101 (3)
HE1_1	0.6075	0.5938	0.4586	0.13 (3)*
CE2_1	0.5814 (17)	0.7715 (6)	0.4157 (3)	0.097 (2)
HE2_1	0.6567	0.8212	0.4217	0.11 (3)*
CZ_1	0.6606 (17)	0.7099 (7)	0.4458 (3)	0.099 (3)
HZ_1	0.7903	0.7166	0.4727	0.10 (2)*
C_1	0.3211 (9)	0.7368 (3)	0.2428 (2)	0.0434 (11)
O_1	0.5602 (6)	0.7299 (2)	0.23854 (16)	0.0564 (10)
N_2	0.1939 (9)	0.8039 (3)	0.22991 (19)	0.0515 (11)
H1_2	0.045 (12)	0.807 (3)	0.234 (2)	0.050 (16)*
CA_2	0.3284 (10)	0.8774 (3)	0.2151 (2)	0.0501 (12)
HA_2	0.4814	0.8823	0.2396	0.067 (16)*
CB_2	0.4310 (11)	0.8754 (4)	0.1553 (2)	0.0591 (14)
HB2_2	0.5347	0.9230	0.1488	0.067 (17)*
HB1_2	0.5473	0.8300	0.1513	0.069 (17)*
CG_2	0.2215 (11)	0.8704 (3)	0.1114 (2)	0.0537 (13)
CD1_2	0.1119 (14)	0.9374 (4)	0.0884 (3)	0.0715 (17)
HD1_2	0.1683	0.9870	0.1007	0.040 (12)*
CD2_2	0.1287 (12)	0.7983 (4)	0.0913 (2)	0.0671 (16)
HD2_2	0.1997	0.7513	0.1052	0.09 (2)*
CE1_2	−0.0777 (17)	0.9339 (5)	0.0480 (3)	0.090 (2)
HE1_2	−0.1456	0.9807	0.0330	0.11 (3)*
CE2_2	−0.0636 (15)	0.7938 (5)	0.0517 (3)	0.0810 (19)
HE2_2	−0.1243	0.7445	0.0398	0.11 (3)*
CZ_2	−0.1665 (16)	0.8621 (5)	0.0296 (3)	0.086 (2)
HZ_2	−0.2960	0.8594	0.0024	0.11 (3)*
C_2	0.1521 (11)	0.9496 (4)	0.2257 (3)	0.0609 (14)
O1_2	−0.0707 (8)	0.9384 (3)	0.2439 (2)	0.0898 (15)
O2_2	0.2435 (10)	1.0170 (3)	0.2143 (2)	0.0885 (15)
O1_3	0.4738 (14)	0.5690 (3)	0.1451 (2)	0.1086 (19)
C2_3	0.525 (3)	0.4887 (5)	0.1322 (4)	0.130 (4)
H22_3	0.5333	0.4574	0.1660	0.156*
H21_3	0.3854	0.4676	0.1090	0.156*
C3_3	0.763 (3)	0.4844 (7)	0.1043 (8)	0.197 (8)
H32_3	0.7454	0.4504	0.0719	0.236*
H31_3	0.8963	0.4618	0.1284	0.236*
C4_3	0.840 (2)	0.5646 (6)	0.0872 (6)	0.139 (4)
H41_3	0.8104	0.5724	0.0477	0.39 (15)*
H42_3	1.0242	0.5743	0.0953	0.465*
C5_3	0.672 (2)	0.6167 (6)	0.1200 (4)	0.122 (3)
H51_3	0.7742	0.6437	0.1483	0.36 (13)*
H52_3	0.5916	0.6567	0.0962	0.433*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N_1	0.050 (3)	0.055 (3)	0.064 (3)	−0.005 (2)	0.003 (3)	0.005 (2)
CA_1	0.030 (2)	0.066 (3)	0.059 (3)	−0.001 (2)	−0.005 (2)	0.003 (2)
CB_1	0.040 (3)	0.072 (4)	0.067 (3)	0.000 (3)	0.007 (3)	0.005 (3)
CG_1	0.051 (3)	0.066 (4)	0.057 (3)	0.000 (3)	0.011 (3)	−0.004 (3)
CD1_1	0.097 (5)	0.074 (5)	0.074 (4)	0.004 (4)	−0.008 (4)	0.006 (4)
CD2_1	0.082 (5)	0.068 (4)	0.074 (4)	0.001 (4)	0.002 (4)	−0.009 (3)
CE1_1	0.108 (6)	0.127 (7)	0.069 (4)	0.046 (6)	−0.019 (5)	0.002 (5)
CE2_1	0.096 (5)	0.104 (6)	0.090 (5)	−0.021 (5)	0.000 (5)	−0.038 (5)
CZ_1	0.076 (5)	0.145 (8)	0.075 (5)	0.013 (6)	−0.016 (4)	−0.040 (5)
C_1	0.033 (2)	0.048 (3)	0.049 (3)	0.005 (2)	−0.004 (2)	0.003 (2)
O_1	0.0317 (16)	0.052 (2)	0.085 (3)	0.0049 (15)	−0.0010 (18)	0.0098 (18)
N_2	0.030 (2)	0.058 (3)	0.067 (3)	0.005 (2)	0.001 (2)	0.004 (2)
CA_2	0.037 (2)	0.048 (3)	0.065 (3)	0.005 (2)	−0.006 (2)	−0.002 (2)
CB_2	0.043 (3)	0.057 (3)	0.078 (3)	0.001 (3)	0.004 (3)	0.007 (3)
CG_2	0.052 (3)	0.054 (3)	0.055 (3)	0.003 (3)	0.016 (2)	0.003 (3)
CD1_2	0.091 (5)	0.055 (4)	0.068 (4)	−0.008 (3)	−0.001 (4)	−0.004 (3)
CD2_2	0.070 (4)	0.058 (4)	0.074 (4)	0.008 (3)	0.005 (3)	−0.005 (3)
CE1_2	0.114 (6)	0.092 (5)	0.066 (4)	0.032 (5)	−0.016 (4)	0.005 (4)
CE2_2	0.084 (4)	0.084 (5)	0.075 (4)	−0.008 (4)	−0.003 (4)	−0.015 (4)
CZ_2	0.086 (5)	0.115 (6)	0.057 (4)	0.014 (5)	−0.005 (4)	−0.015 (4)
C_2	0.050 (3)	0.057 (4)	0.075 (4)	0.002 (3)	−0.017 (3)	−0.011 (3)
O1_2	0.048 (2)	0.075 (3)	0.147 (4)	0.007 (2)	0.009 (3)	−0.028 (3)
O2_2	0.081 (3)	0.057 (3)	0.127 (4)	0.002 (2)	−0.020 (3)	−0.003 (2)
O1_3	0.133 (5)	0.093 (4)	0.100 (4)	−0.007 (4)	0.033 (4)	−0.001 (3)
C2_3	0.173 (10)	0.080 (6)	0.138 (7)	−0.004 (6)	0.057 (8)	−0.011 (5)
C3_3	0.170 (12)	0.114 (9)	0.31 (2)	0.011 (9)	0.120 (14)	0.001 (10)
C4_3	0.109 (7)	0.121 (8)	0.188 (11)	−0.008 (6)	0.050 (8)	0.017 (7)
C5_3	0.130 (8)	0.119 (7)	0.118 (6)	−0.026 (7)	0.050 (7)	−0.013 (6)

Geometric parameters (Å, º)

N_1—CA_1	1.485 (7)	CB_2—HB2_2	0.9700
N_1—H3_1	1.14 (7)	CB_2—HB1_2	0.9700
N_1—H2_1	1.04 (7)	CG_2—CD1_2	1.370 (8)
N_1—H1_1	0.80 (6)	CG_2—CD2_2	1.387 (8)
CA_1—CB_1	1.516 (8)	CD1_2—CE1_2	1.371 (10)
CA_1—C_1	1.519 (7)	CD1_2—HD1_2	0.9300
CA_1—HA_1	0.9800	CD2_2—CE2_2	1.367 (9)
CB_1—CG_1	1.495 (8)	CD2_2—HD2_2	0.9300
CB_1—HB2_1	0.9700	CE1_2—CZ_2	1.361 (10)
CB_1—HB1_1	0.9700	CE1_2—HE1_2	0.9300
CG_1—CD2_1	1.378 (8)	CE2_2—CZ_2	1.365 (10)
CG_1—CD1_1	1.388 (9)	CE2_2—HE2_2	0.9300
CD1_1—CE1_1	1.386 (11)	CZ_2—HZ_2	0.9300
CD1_1—HD1_1	0.9300	C_2—O1_2	1.228 (7)
CD2_1—CE2_1	1.378 (11)	C_2—O2_2	1.254 (7)
CD2_1—HD2_1	0.9300	O1_3—C2_3	1.407 (10)
CE1_1—CZ_1	1.358 (12)	O1_3—C5_3	1.422 (11)
CE1_1—HE1_1	0.9300	C2_3—C3_3	1.384 (16)
CE2_1—CZ_1	1.324 (12)	C2_3—H22_3	0.9700
CE2_1—HE2_1	0.9300	C2_3—H21_3	0.9700
CZ_1—HZ_1	0.9300	C3_3—C4_3	1.460 (15)
C_1—O_1	1.224 (6)	C3_3—H32_3	0.9700
C_1—N_2	1.335 (6)	C3_3—H31_3	0.9700
N_2—CA_2	1.455 (7)	C4_3—C5_3	1.459 (13)
N_2—H1_2	0.77 (6)	C4_3—H41_3	0.9700
CA_2—C_2	1.529 (8)	C4_3—H42_3	0.9700
CA_2—CB_2	1.532 (7)	C5_3—H51_3	0.9700
CA_2—HA_2	0.9800	C5_3—H52_3	0.9700
CB_2—CG_2	1.501 (8)
CA_1—N_1—H3_1	117 (3)	CA_2—CB_2—HB2_2	108.5
CA_1—N_1—H2_1	122 (3)	CG_2—CB_2—HB1_2	108.6
H3_1—N_1—H2_1	103 (4)	CA_2—CB_2—HB1_2	108.6
CA_1—N_1—H1_1	110 (4)	HB2_2—CB_2—HB1_2	107.5
H3_1—N_1—H1_1	110 (5)	CD1_2—CG_2—CD2_2	116.0 (5)
H2_1—N_1—H1_1	91 (5)	CD1_2—CG_2—CB_2	121.7 (5)
N_1—CA_1—CB_1	111.5 (5)	CD2_2—CG_2—CB_2	122.3 (5)
N_1—CA_1—C_1	109.0 (4)	CE1_2—CD1_2—CG_2	122.5 (6)
CB_1—CA_1—C_1	112.7 (4)	CE1_2—CD1_2—HD1_2	118.8
N_1—CA_1—HA_1	107.8	CG_2—CD1_2—HD1_2	118.8
CB_1—CA_1—HA_1	107.8	CE2_2—CD2_2—CG_2	122.2 (6)
C_1—CA_1—HA_1	107.8	CE2_2—CD2_2—HD2_2	118.9
CG_1—CB_1—CA_1	116.2 (4)	CG_2—CD2_2—HD2_2	118.9
CG_1—CB_1—HB2_1	108.2	CZ_2—CE1_2—CD1_2	120.0 (7)
CA_1—CB_1—HB2_1	108.2	CZ_2—CE1_2—HE1_2	120.0
CG_1—CB_1—HB1_1	108.2	CD1_2—CE1_2—HE1_2	120.0
CA_1—CB_1—HB1_1	108.2	CZ_2—CE2_2—CD2_2	119.9 (7)
HB2_1—CB_1—HB1_1	107.4	CZ_2—CE2_2—HE2_2	120.1
CD2_1—CG_1—CD1_1	116.7 (6)	CD2_2—CE2_2—HE2_2	120.0
CD2_1—CG_1—CB_1	122.0 (6)	CE1_2—CZ_2—CE2_2	119.4 (7)
CD1_1—CG_1—CB_1	121.3 (6)	CE1_2—CZ_2—HZ_2	120.3
CE1_1—CD1_1—CG_1	120.8 (7)	CE2_2—CZ_2—HZ_2	120.3
CE1_1—CD1_1—HD1_1	119.6	O1_2—C_2—O2_2	123.9 (6)
CG_1—CD1_1—HD1_1	119.6	O1_2—C_2—CA_2	118.6 (6)
CG_1—CD2_1—CE2_1	121.1 (7)	O2_2—C_2—CA_2	117.5 (5)
CG_1—CD2_1—HD2_1	119.4	C2_3—O1_3—C5_3	108.5 (8)
CE2_1—CD2_1—HD2_1	119.4	C3_3—C2_3—O1_3	108.7 (10)
CZ_1—CE1_1—CD1_1	120.2 (8)	C3_3—C2_3—H22_3	109.8
CZ_1—CE1_1—HE1_1	120.0	O1_3—C2_3—H22_3	109.9
CD1_1—CE1_1—HE1_1	119.9	C3_3—C2_3—H21_3	110.1
CZ_1—CE2_1—CD2_1	121.3 (8)	O1_3—C2_3—H21_3	110.0
CZ_1—CE2_1—HE2_1	119.3	H22_3—C2_3—H21_3	108.3
CD2_1—CE2_1—HE2_1	119.4	C2_3—C3_3—C4_3	108.6 (10)
CE2_1—CZ_1—CE1_1	119.9 (7)	C2_3—C3_3—H32_3	109.8
CE2_1—CZ_1—HZ_1	120.1	C4_3—C3_3—H32_3	109.5
CE1_1—CZ_1—HZ_1	120.0	C2_3—C3_3—H31_3	110.1
O_1—C_1—N_2	122.7 (5)	C4_3—C3_3—H31_3	110.5
O_1—C_1—CA_1	121.7 (4)	H32_3—C3_3—H31_3	108.3
N_2—C_1—CA_1	115.6 (4)	C5_3—C4_3—C3_3	104.3 (9)
C_1—N_2—CA_2	123.0 (4)	C5_3—C4_3—H41_3	110.4
C_1—N_2—H1_2	120 (4)	C3_3—C4_3—H41_3	110.4
CA_2—N_2—H1_2	116 (4)	C5_3—C4_3—H42_3	111.3
N_2—CA_2—C_2	110.9 (4)	C3_3—C4_3—H42_3	111.5
N_2—CA_2—CB_2	111.8 (4)	H41_3—C4_3—H42_3	109.0
C_2—CA_2—CB_2	112.0 (4)	O1_3—C5_3—C4_3	107.5 (8)
N_2—CA_2—HA_2	107.3	O1_3—C5_3—H51_3	110.2
C_2—CA_2—HA_2	107.3	C4_3—C5_3—H51_3	110.7
CB_2—CA_2—HA_2	107.3	O1_3—C5_3—H52_3	110.2
CG_2—CB_2—CA_2	114.8 (4)	C4_3—C5_3—H52_3	109.8
CG_2—CB_2—HB2_2	108.6	H51_3—C5_3—H52_3	108.4