Mol­ecular aggregation in selected crystalline 1:1 complexes of hydro­phobic D- and L-amino acids. IV. The L-phenyl­alanine series

The amino acid L-phenyl­alanine has been cocrystallized with D-2-amino­butyric acid, C₉H₁₁NO₂·C₄H₉NO₂, D-norvaline, C₉H₁₁NO₂·C₅H₁₁NO₂, and D-methio­nine, C₉H₁₁NO₂·C₅H₁₁NO₂S, with linear side chains, as well as with D-leucine, C₉H₁₁NO₂·C₆H₁₃NO₂, D-isoleucine, C₉H₁₁NO₂·C₆H₁₃NO₂, and D-allo-isoleucine, C₉H₁₁NO₂·C₆H₁₃NO₂, with branched side chains. The structures of these 1:1 complexes fall into two classes based on the observed hydrogen-bonding pattern. From a comparison with other L:D complexes involving hydro­phobic amino acids and regular racemates, it is shown that the structure-directing properties of phenyl­alanine closely parallel those of valine and isoleucine but not those of leucine, which shares side-chain branching at C^[gamma] with phenyl­alanine and is normally considered to be the most closely related non-aromatic amino acid.

S1. Comment

In three papers, we have presented the structures of various complexes between hydrophobic L- and D-amino acids (Dalhus & Görbitz, 1999a,b,c). All of these crystals are divided into hydrophilic and hydrophobic layers, with the former incorporating the same hydrogen-bonding patterns as found in the crystal structures of regular amino acid racemates. The mixed L:D complexes are thus often referred to as pseudo-racemates, the difference from normal racemates being confined to the hydrophobic regions of the crystal structures. A closer look at the hydrophilic layers shows that they are generated from two distinct sheets, shown schematically in Fig. 1. Hydrogen bonding within a sheet engages two of the amino H atoms, while the third serves as a sheet connector. Only two types of sheets have been found for (pseudo)racemates. The first is called LD and incorporates a mixture of L- and D-enantiomers, while the second arrangement involves amino acids of one hand only and is called L1 when constructed from L-amino acids and D1 when constructed from D-amino acids (Fig. 2). The sheets give rise to two types of layers: LD–LD, characterized by the presence of (pseudo)glide planes, and L1–D1 in which adjacent sheets are related by (pseudo)inversion. Theoretical ab initio calculations have indicated that the LD–LD layer, occurring in what has been referred to as class I crystal structures, is inherently preferred over L1–D1 (class II) as far as the hydrogen-bonding energy is concerned (Dalhus & Görbitz, 2004; Görbitz et al., 2009). Steric conflict may nevertheless lead to L1–D1 structures, and Dalhus (2000) gave the following empirical rules for the effect of the side chain: (i) Complexes with two linear amino acids crystallize in class I. (ii) Complexes with two branched amino acids crystallize in class II. (iii) Complexes with one linear and one branched amino acid crystallize in both class I and class II; branching at Cβ(Ile/Val) gives class I structures, while branching at Cγ(Leu) gives class II structures.

Our previous investigations included Ala, 2-aminobutyric acid (Abu), norvaline (Nva), norleucine (Nle) and Met with linear side chains, as well as Val, Ile, allo-isoleucine (aIle) and Leu with branched side chains, but not Phe. The only known structure of a 1:1 amino acid complex with this aromatic amino acid is L-Phe:D-Val (Prasad & Vijayan, 1991), which, in accordance with the observations of Dalhus (2000), forms a class II structure. Apart from this, the structure-directing properties of Phe in such complexes are unknown. In the structures of various peptides Phe can often be replaced by Leu, both with branching at Cγ, without major structure modifications, while isostructural peptides with Phe substituted for Ile or Val are less common. We thus anticipated that amino acid complexes with Phe would mimic the equivalent complexes with Leu. In order to verify this hypothesis, attempts were made to crystallize L-Phe with the D-enantiomer of all other hydrophobic amino acids listed above (except D-Val, but including D-Phe). Three complexes, L-Phe:D-Ala, L-Phe:D-Nle and DL-Phe, failed to give diffraction quality crystals, meaning that the present investigation deals with L-Phe in complex with the three linear amino acids D-Abu, D-Nva and D-Met as well as the three branched amino acids D-Leu, D-Ile and D-aIle (see scheme).

The asymmetric units of complexes between L-Phe and D-amino acids with linear and branched side chains are shown in Figs. 3 and 4, respectively. All structures are well ordered, but extensive thermal vibrations for certain side chains are evident, causing a significant artificial shortening of some covalent bond lengths such as C6A—C7A = 1.318 (6) Å for L-Phe:D-Leu. Packing diagrams are shown in Figs. 5 and 6. The hydrogen bonds observed in the six structures (Tables 1–6) follow closely the observed patterns for other LD—LD (class I) and L1—D1 (class II) structures. There is always a `knots-in-holes' fit at the hydrophobic interface (Fig. 1), but this is much more pronounced for class I structures than for class II structures owing to the involvement of two different amino acids in the formation of each hydrogen-bonded sheet, as illustrated for L-Phe:D-Abu in Fig. 5 and L-Phe:D-Leu in Fig. 6.

Dalhus (2000) previously noted that complexes between aIle and other amino acids, if formed at all, invariably yielded crystals of poor quality, in marked contrast to the corresponding complexes with Ile and Leu. A comparison of the unit-cell dimensions of complexes with Nva, Nle and Met (Dalhus & Görbitz, 1999a,b,c; Dalhus, 2000) shows that incorporation of aIle leads to a 6–18 ų increase in the volumes of the asymmetric unit compared with Ile or Leu, clearly indicating a less efficient packing of the hydrophobic side chains. In the present study, aIle shows no such deviating crystallization habit, and the asymmetric unit volume of L-Phe:D-aIle (386.2 ų) is midway between the values of 384.8 ų for L-Phe:D-Ile and 391.0 ų for L-Phe:D-Leu. The 6.2 ų range is dwarfed by the 22.7 ų difference between L-Leu:D-Abu (310.5 ų) and DL-Val (287.8 ų for the LD pair; Flaig et al., 2002), the more compact hydrophobic layer for the latter being easily recognized in Fig. 6 (note that the total number of side-chain C atoms remains unchanged).

Class I structures usually distribute evenly between the monoclinic space groups C2 and P2₁, as exemplified in Fig. 5 by L-Ile:D-Nva (Dalhus & Görbitz, 1999a) and D-Nle:L-Met (Dalhus & Görbitz, 1999b), respectively. L-Phe:D-Met is isostructural to D-Nle:L-Met (disregarding the shifts in chirality) and about five other complexes. The orthorhombic P2₁2₁2₁ structures of L-Phe:D-Abu and L-Phe:D-Nva, on the other hand, have been preceded only by the structure of L-Val:D-Met (Dalhus & Görbitz, 1999c) (Fig. 5). For the pseudosymmetric class II complexes there is also an even distribution between two space groups, in this case P1 and P2₁. The monoclinic system has been chosen for L-Phe:D-Leu and L-Phe:D-aIle, and the triclinic for L-Phe:D-Ile, which is strikingly similar to the structure of D-Leu:L-Ile (Dalhus & Görbitz, 1999a) (Fig. 6). This example serves to illustrate that as long as the partner molecule has a branched side chain, Phe behaves similarly to Leu, or indeed similarly to any other amino acid with a branched side chain, in producing class II structures. Included in this group are also true racemates such as DL-Val (Fig. 6; Flaig et al., 2002). The difference between Leu and Phe becomes apparent when a comparison in made between L-Phe:D-Abu (Fig. 5) and L-Leu:D-Abu (Fig. 6). Even when paired with Abu, with a relatively small ethyl side chain, Leu is unable to form a class I complex, while Phe forms class I complexes with any amino acid with a linear side chain. The origin of this important difference between Leu and Phe can be derived from an analysis of amino acid side-chain rotamers (Table 7). The table shows that Met is the only amino acid to display any conformational variation within class I. In fact, it occurs with three different side-chain conformations for χ¹,χ²,χ³ (L enantiomer): gauche-,trans,trans, gauche-,trans,gauche+ and finally trans,trans,gauche-, which is also observed in the class II complex with Leu (Dalhus & Görbitz, 1999c). More important is that Table 7 reveals systematic conformational shifts upon change of class, which is evidently a requirement for proper stacking of side chains in the hydrophobic layers. It is then essential that Leu, as the only amino acid, is unable to undergo such a shift as it is restricted to the trans, gauche+/trans conformation for χ¹,χ^2,1/χ^2,2 (L enantiomer; Görbitz, 2006).

In summary, in complexes with other hydrophobic amino acids, L-Phe displays the same structure-directing properties as the Cβ-branched amino acids Val, Ile and aIle. This means that complexes with linear amino acids form class I (LD–LD) structures, while complexes with branched side chains from class II (L1–D1) structures. The ability of Phe to form the tightly packed LD sheets required for formation of an LD–LD class I layer stems from the availability of more than one possible conformation upon rotation around the Cα—Cβ bond. In contrast, Leu, which like Phe is branched at Cγ, has only a single viable side-chain conformation and is consequently limited to class II structures with L1–D1 hydrogen-bonded layers.

Related literature

For related literature, see: Dalhus (2000); Dalhus & Görbitz (1999a, 1999b, 1999c, 2004); Flaig et al. (2002); Görbitz (2006); Görbitz et al. (2009); Prasad & Vijayan (1991).

S2. Experimental

Aqueous solutions of the selected complexes were prepared by dissolving equimolar amounts (typically 1 mg of each) of the two selected amino acids in 90 µl of deionized water. The mixture was distributed into three 30 × 5 mm test tubes and sealed with Parafilm, in which a couple of small holes were then pricked with a needle. Usable crystals emerged for five complexes as acetonitrile diffused into the solutions at room temperature. For the sixth, L-Phe:D-Abu, additional crystallizations had to be carried out. These employed, rather than pure water as the solvent, a mixture of water (80 µl) and tetramethoxysilane (20 µl). After vigorous stirring for about 1 min, the mixture was left to polymerize into a gel (1 h). Equilibration against acetonitrile subsequently proceeded as above, producing in the gel larger crystals of good quality.

S3. Refinement

H atoms bonded to C atoms were positioned with idealized geometry and C—H distances fixed in the range 0.93–0.98 Å. Positional parameters were refined for H atoms bonded to N atoms, but with a mild SHELXTL restraint for the N—H distances, which accordingly varied between 0.88 (2) and 0.95 (3) Å. U_iso(H) values were 1.2U_eq of the carrier atom, or 1.5U_eq for amino and methyl groups. Friedel pairs were merged for all data sets except L-Phe:D-Met, for which the anomalous scattering effects of 1082 Friedel pairs were used to confirm the known absolute configurations of the complex components.

Computing details

For all compounds, data collection: APEX2 (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008a); program(s) used to refine structure: SHELXTL (Sheldrick, 2008a); molecular graphics: SHELXTL (Sheldrick, 2008a); software used to prepare material for publication: SHELXTL (Sheldrick, 2008a).

Figures

	Fig. 1. : Schematic illustration of the construction of the crystal structures of hydrophobic amino acids (as enantiomers, racemates or L:D complexes). The structures are divided into hydrophobic and hydrophilic layers; the latter is in turn composed of two hydrogen-bonded sheets. At the centre of the hydrophobic layer there is an interface between side chains emanating from adjacent hydrophilic layers.
	Fig. 2. : The two types of sheets observed for racemates and pseudo-racemates of hydrophobic amino acids. The D enantiomers in the LD sheet are coloured in a darker grey tone. For clarity, side chains have been replaced by a H atom.
	Fig. 3. : The molecular structure of L-Phe:D-Abu (top), L-Phe:D-Nva (middle) and L-Phe:D-Met (bottom). Displacement ellipsoids are shown at the 50% probability level and H atoms are shown as spheres of arbitrary size.
	Fig. 4. : The molecular structure of L-Phe:D-Leu (top), L-Phe:D-Ile (middle) and L-Phe:D-aIle (bottom). Displacement ellipsoids are shown at the 50% probability level and H atoms are shown as spheres of arbitrary size.
	Fig. 5. : The molecular packing and unit cell of L-Phe:D-Abu (space group P212121), L-Phe:D-Nva (P212121) and L-Phe:D-Met (P21), together with L-Val:D-Met (P212121; Dalhus & Görbitz, 1999c), L-Ile:D-Nva (C2; Dalhus & Görbitz, 1999a) and D-Nle:L-Met (P21; Dalhus & Görbitz, 1999b), with Cambridge Structural Database refcodes (Allen, 2002). A hydrophobic interface has been indicated for L-Phe:D-Abu; circles highlight different Met conformations. In the electronic version of the pape, colouring of side chains in Figs. 5 and 6 has been used to emphasize structural similarities and not the chirality of the amino acid.
	Fig. 6. : The molecular packing and unit cell of L-Phe:D-Leu (P21, with hydrophobic interface), L-Phe:D-Ile (P1) and L-Phe:D-aIle (P21), together with L-Leu:D-Abu (P21; Dalhus & Görbitz, 1999c), D-Leu:L-Ile (P1; Dalhus & Görbitz, 1999b) and DL-Val (P1; Flaig et al., 2002).

(I) L-Phenylalanine–D-2-ammoniobutyrate (1/1)

Crystal data

C9H11NO2·C4H9NO2	F(000) = 576
Mr = 268.31	Dx = 1.316 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: p 2ac 2ab	Cell parameters from 3167 reflections
a = 4.7869 (7) Å	θ = 2.2–25.0°
b = 9.9558 (15) Å	µ = 0.10 mm^−1
c = 28.423 (4) Å	T = 296 K
V = 1354.6 (3) Å^3	Flat needle, colourless
Z = 4	0.80 × 0.12 × 0.04 mm

Data collection

Bruker APEXII CCD diffractometer	1443 independent reflections
Radiation source: fine-focus sealed tube	1284 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.037
Detector resolution: 8.3 pixels mm^-1	θmax = 25.0°, θmin = 2.2°
Sets of exposures each taken over 0.5° ω rotation scans	h = −5→5
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	k = −11→11
Tmin = 0.770, Tmax = 0.996	l = −33→33
10082 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0794P)^2 + 0.2457P] where P = (Fo^2 + 2Fc^2)/3
1443 reflections	(Δ/σ)max = 0.001
191 parameters	Δρmax = 0.24 e Å^−3
6 restraints	Δρmin = −0.18 e Å^−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.

Refinement. Data were collected by measuring four sets of exposures with the detector set at 2θ = 29°, crystal-to-detector distance 6.00 cm. Refinement of F² against ALL reflections.

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

	x	y	z	Uiso*/Ueq
O1A	0.0384 (4)	0.19658 (19)	0.03353 (6)	0.0342 (5)
O2A	0.3090 (5)	0.03509 (18)	0.06282 (8)	0.0401 (6)
N1A	0.4115 (5)	0.3904 (2)	0.05721 (8)	0.0285 (5)
H1A	0.540 (7)	0.452 (3)	0.0682 (11)	0.043*
H2A	0.233 (6)	0.430 (3)	0.0596 (12)	0.043*
H3A	0.442 (7)	0.368 (3)	0.0262 (8)	0.043*
C1A	0.4154 (6)	0.2600 (3)	0.08330 (9)	0.0253 (6)
H11A	0.6083	0.2280	0.0862	0.030*
C2A	0.2871 (7)	0.2747 (3)	0.13221 (9)	0.0349 (7)
H21A	0.0991	0.3095	0.1285	0.042*
H22A	0.2713	0.1858	0.1459	0.042*
C3A	0.4397 (7)	0.3634 (3)	0.16678 (9)	0.0329 (7)
C4A	0.3735 (8)	0.4988 (3)	0.17116 (12)	0.0467 (9)
H41A	0.2388	0.5367	0.1517	0.056*
C5A	0.5066 (11)	0.5772 (4)	0.20426 (12)	0.0601 (11)
H51A	0.4599	0.6675	0.2070	0.072*
C6A	0.7070 (10)	0.5239 (4)	0.23330 (13)	0.0623 (12)
H61A	0.7954	0.5777	0.2555	0.075*
C7A	0.7760 (9)	0.3906 (4)	0.22931 (12)	0.0568 (10)
H71A	0.9121	0.3536	0.2487	0.068*
C8A	0.6419 (8)	0.3117 (4)	0.19620 (10)	0.0439 (8)
H81A	0.6893	0.2213	0.1937	0.053*
C9A	0.2417 (6)	0.1562 (2)	0.05665 (9)	0.0253 (6)
O1B	1.1859 (5)	0.6907 (2)	0.04024 (7)	0.0371 (5)
O2B	0.9078 (5)	0.54024 (18)	0.07490 (8)	0.0403 (6)
N1B	0.8067 (6)	0.8884 (2)	0.05042 (9)	0.0301 (5)
H1B	0.671 (7)	0.952 (3)	0.0583 (11)	0.045*
H2B	0.796 (8)	0.859 (3)	0.0191 (8)	0.045*
H3B	0.978 (6)	0.930 (3)	0.0506 (12)	0.045*
C1B	0.7978 (6)	0.7720 (3)	0.08327 (9)	0.0285 (6)
H11B	0.6043	0.7412	0.0866	0.034*
C2B	0.9099 (7)	0.8129 (3)	0.13141 (9)	0.0362 (7)
H21B	1.1051	0.8373	0.1282	0.043*
H22B	0.8998	0.7360	0.1523	0.043*
C3B	0.7520 (9)	0.9307 (3)	0.15403 (11)	0.0536 (10)
H31B	0.8297	0.9492	0.1845	0.080*
H32B	0.5582	0.9077	0.1573	0.080*
H33B	0.7695	1.0089	0.1345	0.080*
C4B	0.9755 (6)	0.6582 (3)	0.06374 (9)	0.0275 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0319 (11)	0.0294 (10)	0.0412 (11)	0.0014 (9)	−0.0079 (9)	−0.0022 (9)
O2A	0.0329 (12)	0.0193 (10)	0.0681 (15)	0.0007 (9)	−0.0057 (12)	−0.0021 (9)
N1A	0.0306 (13)	0.0212 (12)	0.0337 (13)	−0.0047 (11)	0.0008 (12)	−0.0020 (10)
C1A	0.0219 (13)	0.0194 (12)	0.0346 (14)	0.0016 (11)	−0.0016 (12)	−0.0005 (10)
C2A	0.0375 (17)	0.0335 (15)	0.0338 (14)	−0.0065 (14)	0.0011 (13)	0.0002 (12)
C3A	0.0398 (17)	0.0333 (15)	0.0256 (13)	−0.0036 (15)	0.0047 (13)	−0.0022 (11)
C4A	0.058 (2)	0.0351 (17)	0.0465 (18)	0.0059 (18)	−0.0011 (17)	−0.0008 (14)
C5A	0.090 (3)	0.0378 (19)	0.053 (2)	−0.006 (2)	0.010 (2)	−0.0126 (16)
C6A	0.074 (3)	0.069 (3)	0.044 (2)	−0.024 (2)	0.000 (2)	−0.0215 (19)
C7A	0.054 (2)	0.072 (3)	0.0449 (19)	−0.003 (2)	−0.0095 (18)	−0.0059 (18)
C8A	0.052 (2)	0.0397 (17)	0.0401 (16)	0.0054 (18)	−0.0016 (15)	−0.0031 (14)
C9A	0.0226 (13)	0.0224 (14)	0.0310 (13)	−0.0009 (12)	0.0045 (12)	−0.0026 (11)
O1B	0.0325 (12)	0.0341 (11)	0.0445 (11)	0.0042 (10)	0.0053 (10)	−0.0047 (9)
O2B	0.0367 (12)	0.0182 (10)	0.0660 (14)	−0.0005 (9)	−0.0011 (11)	−0.0028 (9)
N1B	0.0306 (13)	0.0221 (12)	0.0377 (13)	0.0020 (11)	−0.0031 (12)	−0.0022 (10)
C1B	0.0258 (14)	0.0209 (13)	0.0387 (15)	−0.0006 (12)	0.0013 (13)	0.0000 (11)
C2B	0.0396 (17)	0.0310 (15)	0.0379 (15)	0.0060 (15)	−0.0029 (14)	−0.0033 (12)
C3B	0.069 (3)	0.047 (2)	0.0444 (18)	0.017 (2)	−0.0087 (19)	−0.0152 (16)
C4B	0.0237 (14)	0.0237 (14)	0.0350 (14)	−0.0007 (12)	−0.0055 (12)	−0.0045 (11)

Geometric parameters (Å, º)

O1A—C9A	1.241 (3)	C6A—H61A	0.9300
O2A—C9A	1.260 (3)	C7A—C8A	1.384 (5)
N1A—C1A	1.496 (3)	C7A—H71A	0.9300
N1A—H1A	0.92 (2)	C8A—H81A	0.9300
N1A—H2A	0.95 (3)	O1B—C4B	1.251 (4)
N1A—H3A	0.92 (2)	O2B—C4B	1.259 (3)
C1A—C2A	1.527 (4)	N1B—C1B	1.488 (3)
C1A—C9A	1.527 (4)	N1B—H1B	0.94 (2)
C1A—H11A	0.9800	N1B—H2B	0.94 (2)
C2A—C3A	1.510 (4)	N1B—H3B	0.92 (3)
C2A—H21A	0.9700	C1B—C4B	1.522 (4)
C2A—H22A	0.9700	C1B—C2B	1.525 (4)
C3A—C8A	1.379 (5)	C1B—H11B	0.9800
C3A—C4A	1.390 (4)	C2B—C3B	1.537 (4)
C4A—C5A	1.378 (5)	C2B—H21B	0.9700
C4A—H41A	0.9300	C2B—H22B	0.9700
C5A—C6A	1.372 (6)	C3B—H31B	0.9600
C5A—H51A	0.9300	C3B—H32B	0.9600
C6A—C7A	1.372 (6)	C3B—H33B	0.9600
C1A—N1A—H1A	113 (2)	C3A—C8A—C7A	121.7 (3)
C1A—N1A—H2A	110 (2)	C3A—C8A—H81A	119.2
H1A—N1A—H2A	108 (3)	C7A—C8A—H81A	119.2
C1A—N1A—H3A	105 (2)	O1A—C9A—O2A	125.8 (3)
H1A—N1A—H3A	112 (3)	O1A—C9A—C1A	118.0 (2)
H2A—N1A—H3A	108 (3)	O2A—C9A—C1A	116.0 (2)
N1A—C1A—C2A	111.3 (2)	C1B—N1B—H1B	111 (2)
N1A—C1A—C9A	109.6 (2)	C1B—N1B—H2B	110 (2)
C2A—C1A—C9A	107.3 (2)	H1B—N1B—H2B	114 (3)
N1A—C1A—H11A	109.6	C1B—N1B—H3B	112 (2)
C2A—C1A—H11A	109.6	H1B—N1B—H3B	108 (3)
C9A—C1A—H11A	109.6	H2B—N1B—H3B	101 (3)
C3A—C2A—C1A	117.0 (2)	N1B—C1B—C4B	109.5 (2)
C3A—C2A—H21A	108.0	N1B—C1B—C2B	110.2 (2)
C1A—C2A—H21A	108.0	C4B—C1B—C2B	109.2 (2)
C3A—C2A—H22A	108.0	N1B—C1B—H11B	109.3
C1A—C2A—H22A	108.0	C4B—C1B—H11B	109.3
H21A—C2A—H22A	107.3	C2B—C1B—H11B	109.3
C8A—C3A—C4A	117.9 (3)	C1B—C2B—C3B	114.0 (3)
C8A—C3A—C2A	121.0 (3)	C1B—C2B—H21B	108.8
C4A—C3A—C2A	121.0 (3)	C3B—C2B—H21B	108.8
C5A—C4A—C3A	120.3 (4)	C1B—C2B—H22B	108.8
C5A—C4A—H41A	119.9	C3B—C2B—H22B	108.8
C3A—C4A—H41A	119.9	H21B—C2B—H22B	107.7
C6A—C5A—C4A	121.0 (4)	C2B—C3B—H31B	109.5
C6A—C5A—H51A	119.5	C2B—C3B—H32B	109.5
C4A—C5A—H51A	119.5	H31B—C3B—H32B	109.5
C7A—C6A—C5A	119.5 (3)	C2B—C3B—H33B	109.5
C7A—C6A—H61A	120.2	H31B—C3B—H33B	109.5
C5A—C6A—H61A	120.2	H32B—C3B—H33B	109.5
C6A—C7A—C8A	119.6 (4)	O1B—C4B—O2B	125.7 (3)
C6A—C7A—H71A	120.2	O1B—C4B—C1B	116.9 (2)
C8A—C7A—H71A	120.2	O2B—C4B—C1B	117.3 (2)
N1A—C1A—C2A—C3A	−65.5 (3)	C6A—C7A—C8A—C3A	0.2 (6)
C9A—C1A—C2A—C3A	174.6 (2)	N1A—C1A—C9A—O1A	−31.2 (3)
C1A—C2A—C3A—C8A	−90.0 (3)	C2A—C1A—C9A—O1A	89.7 (3)
C1A—C2A—C3A—C4A	92.4 (4)	N1A—C1A—C9A—O2A	153.2 (2)
C8A—C3A—C4A—C5A	−0.4 (5)	C2A—C1A—C9A—O2A	−85.8 (3)
C2A—C3A—C4A—C5A	177.3 (3)	N1B—C1B—C2B—C3B	57.7 (3)
C3A—C4A—C5A—C6A	0.3 (6)	C4B—C1B—C2B—C3B	178.1 (3)
C4A—C5A—C6A—C7A	0.0 (6)	N1B—C1B—C4B—O1B	32.3 (3)
C5A—C6A—C7A—C8A	−0.3 (6)	C2B—C1B—C4B—O1B	−88.5 (3)
C4A—C3A—C8A—C7A	0.2 (5)	N1B—C1B—C4B—O2B	−151.8 (3)
C2A—C3A—C8A—C7A	−177.5 (3)	C2B—C1B—C4B—O2B	87.4 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O2B	0.92 (2)	1.98 (3)	2.850 (3)	157 (3)
N1A—H2A···O2B^i	0.95 (3)	1.95 (3)	2.879 (3)	167 (3)
N1A—H3A···O1A^ii	0.92 (2)	1.87 (2)	2.788 (3)	172 (3)
N1B—H1B···O2A^iii	0.94 (2)	1.92 (3)	2.817 (3)	159 (3)
N1B—H2B···O1B^iv	0.94 (2)	1.83 (2)	2.756 (3)	166 (3)
N1B—H3B···O2A^v	0.92 (3)	1.93 (3)	2.835 (3)	168 (3)

Symmetry codes: (i) x−1, y, z; (ii) x+1/2, −y+1/2, −z; (iii) x, y+1, z; (iv) x−1/2, −y+3/2, −z; (v) x+1, y+1, z.

(II) L-Phenylalanine–D-norvaline (1/1)

Crystal data

C9H11NO2·C5H11NO2	F(000) = 608
Mr = 282.34	Dx = 1.278 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 10916 reflections
a = 4.7624 (8) Å	θ = 2.2–25.0°
b = 9.9569 (17) Å	µ = 0.09 mm^−1
c = 30.935 (6) Å	T = 296 K
V = 1466.9 (5) Å^3	Flat needle, colourless
Z = 4	0.48 × 0.14 × 0.05 mm

Data collection

Bruker APEXII CCD diffractometer	1564 independent reflections
Radiation source: fine-focus sealed tube	1395 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.037
Detector resolution: 8.3 pixels mm^-1	θmax = 25.0°, θmin = 2.2°
Sets of exposures each taken over 0.5° ω rotation scans	h = −5→5
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	k = −11→11
Tmin = 0.862, Tmax = 0.995	l = −36→36
14224 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.093	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0318P)^2 + 0.7814P] where P = (Fo^2 + 2Fc^2)/3
1564 reflections	(Δ/σ)max < 0.001
200 parameters	Δρmax = 0.20 e Å^−3
6 restraints	Δρmin = −0.15 e Å^−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.

Refinement. Data were collected by measuring four sets of exposures with the detector set at 2θ = 29°, crystal-to-detector distance 6.00 cm. Refinement of F² against ALL reflections.

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

	x	y	z	Uiso*/Ueq
O1A	−0.0266 (4)	0.19410 (19)	0.03104 (6)	0.0361 (5)
O2A	0.2466 (5)	0.03710 (18)	0.05989 (7)	0.0422 (6)
N1A	0.3413 (6)	0.3907 (2)	0.05212 (8)	0.0297 (5)
H1A	0.481 (6)	0.446 (3)	0.0620 (10)	0.045*
H2A	0.374 (7)	0.367 (3)	0.0234 (7)	0.045*
H3A	0.177 (6)	0.435 (3)	0.0547 (10)	0.045*
C1A	0.3439 (6)	0.2630 (2)	0.07710 (8)	0.0277 (6)
H11A	0.5379	0.2322	0.0806	0.033*
C2A	0.2084 (7)	0.2805 (3)	0.12154 (8)	0.0389 (7)
H21A	0.0217	0.3171	0.1173	0.047*
H22A	0.1864	0.1922	0.1343	0.047*
C3A	0.3587 (7)	0.3680 (3)	0.15365 (8)	0.0362 (7)
C4A	0.2970 (9)	0.5025 (3)	0.15766 (10)	0.0534 (9)
H41A	0.1653	0.5412	0.1393	0.064*
C5A	0.4275 (11)	0.5808 (4)	0.18850 (12)	0.0695 (13)
H51A	0.3819	0.6713	0.1909	0.083*
C6A	0.6217 (11)	0.5265 (5)	0.21529 (12)	0.0741 (13)
H61A	0.7085	0.5793	0.2362	0.089*
C7A	0.6892 (11)	0.3940 (5)	0.21153 (12)	0.0801 (14)
H71A	0.8238	0.3566	0.2297	0.096*
C8A	0.5582 (9)	0.3157 (4)	0.18092 (11)	0.0589 (10)
H81A	0.6059	0.2254	0.1787	0.071*
C9A	0.1753 (6)	0.1564 (3)	0.05297 (8)	0.0273 (6)
O1B	1.1154 (4)	0.69071 (19)	0.03545 (6)	0.0368 (5)
O2B	0.8361 (5)	0.54126 (18)	0.06687 (7)	0.0408 (5)
N1B	0.7435 (6)	0.8904 (2)	0.04696 (8)	0.0302 (5)
H1B	0.613 (6)	0.954 (3)	0.0539 (10)	0.045*
H2B	0.917 (6)	0.928 (3)	0.0489 (10)	0.045*
H3B	0.719 (7)	0.858 (3)	0.0184 (8)	0.045*
C1B	0.7330 (6)	0.7718 (2)	0.07604 (8)	0.0288 (6)
H11B	0.5379	0.7423	0.0795	0.035*
C2B	0.8568 (7)	0.8073 (3)	0.12044 (8)	0.0367 (7)
H21B	0.8467	0.7281	0.1386	0.044*
H22B	1.0540	0.8286	0.1166	0.044*
C3B	0.7200 (9)	0.9225 (3)	0.14436 (9)	0.0498 (9)
H31B	0.5210	0.9045	0.1477	0.060*
H32B	0.7405	1.0044	0.1277	0.060*
C4B	0.8527 (11)	0.9412 (4)	0.18845 (10)	0.0644 (12)
H41B	0.7472	1.0063	0.2046	0.097*
H42B	1.0424	0.9721	0.1850	0.097*
H43B	0.8526	0.8572	0.2036	0.097*
C5B	0.9062 (6)	0.6585 (3)	0.05702 (8)	0.0269 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0328 (12)	0.0312 (11)	0.0442 (11)	−0.0006 (10)	−0.0099 (10)	−0.0034 (9)
O2A	0.0337 (12)	0.0227 (10)	0.0701 (14)	0.0012 (9)	−0.0045 (12)	−0.0033 (10)
N1A	0.0289 (13)	0.0251 (12)	0.0350 (13)	−0.0011 (11)	0.0018 (12)	−0.0032 (10)
C1A	0.0246 (14)	0.0232 (13)	0.0353 (14)	0.0021 (12)	−0.0015 (13)	−0.0012 (11)
C2A	0.0419 (19)	0.0379 (16)	0.0369 (15)	−0.0063 (16)	0.0028 (15)	0.0011 (13)
C3A	0.0391 (18)	0.0395 (16)	0.0299 (14)	−0.0018 (16)	0.0037 (14)	−0.0010 (12)
C4A	0.070 (3)	0.0435 (18)	0.0470 (18)	0.003 (2)	−0.007 (2)	−0.0039 (15)
C5A	0.096 (4)	0.053 (2)	0.060 (2)	−0.014 (3)	0.009 (3)	−0.0164 (19)
C6A	0.078 (3)	0.095 (3)	0.049 (2)	−0.030 (3)	0.000 (2)	−0.025 (2)
C7A	0.074 (3)	0.121 (4)	0.045 (2)	0.009 (3)	−0.023 (2)	−0.010 (2)
C8A	0.066 (3)	0.065 (2)	0.0457 (19)	0.017 (2)	−0.0104 (19)	−0.0037 (18)
C9A	0.0206 (14)	0.0276 (15)	0.0337 (14)	0.0008 (12)	0.0040 (13)	−0.0020 (11)
O1B	0.0332 (12)	0.0358 (11)	0.0413 (11)	0.0032 (10)	0.0065 (10)	−0.0043 (9)
O2B	0.0340 (12)	0.0215 (10)	0.0669 (14)	−0.0005 (9)	−0.0007 (11)	−0.0031 (9)
N1B	0.0290 (13)	0.0263 (13)	0.0353 (12)	0.0036 (11)	−0.0039 (12)	−0.0038 (10)
C1B	0.0240 (14)	0.0244 (13)	0.0379 (14)	−0.0001 (12)	0.0022 (13)	−0.0014 (11)
C2B	0.0385 (17)	0.0359 (15)	0.0357 (15)	0.0058 (16)	0.0015 (14)	0.0026 (13)
C3B	0.054 (2)	0.0521 (19)	0.0431 (17)	0.0094 (19)	−0.0017 (18)	−0.0112 (15)
C4B	0.086 (3)	0.065 (2)	0.0424 (18)	0.009 (3)	−0.006 (2)	−0.0136 (17)
C5B	0.0223 (15)	0.0278 (15)	0.0307 (14)	−0.0007 (12)	−0.0075 (13)	−0.0046 (11)

Geometric parameters (Å, º)

O1A—C9A	1.235 (3)	C7A—H71A	0.9300
O2A—C9A	1.254 (3)	C8A—H81A	0.9300
N1A—C1A	1.488 (3)	O1B—C5B	1.241 (3)
N1A—H1A	0.92 (2)	O2B—C5B	1.252 (3)
N1A—H2A	0.93 (2)	N1B—C1B	1.486 (3)
N1A—H3A	0.90 (2)	N1B—H1B	0.91 (2)
C1A—C9A	1.526 (4)	N1B—H2B	0.91 (2)
C1A—C2A	1.528 (4)	N1B—H3B	0.95 (2)
C1A—H11A	0.9800	C1B—C5B	1.516 (4)
C2A—C3A	1.503 (4)	C1B—C2B	1.536 (4)
C2A—H21A	0.9700	C1B—H11B	0.9800
C2A—H22A	0.9700	C2B—C3B	1.512 (4)
C3A—C8A	1.374 (5)	C2B—H21B	0.9700
C3A—C4A	1.376 (4)	C2B—H22B	0.9700
C4A—C5A	1.380 (5)	C3B—C4B	1.515 (4)
C4A—H41A	0.9300	C3B—H31B	0.9700
C5A—C6A	1.354 (6)	C3B—H32B	0.9700
C5A—H51A	0.9300	C4B—H41B	0.9600
C6A—C7A	1.362 (6)	C4B—H42B	0.9600
C6A—H61A	0.9300	C4B—H43B	0.9600
C7A—C8A	1.376 (5)
C1A—N1A—H1A	110 (2)	O1A—C9A—O2A	126.3 (3)
C1A—N1A—H2A	105.9 (18)	O1A—C9A—C1A	117.8 (2)
H1A—N1A—H2A	111 (3)	O2A—C9A—C1A	115.7 (2)
C1A—N1A—H3A	112 (2)	C1B—N1B—H1B	113 (2)
H1A—N1A—H3A	108 (3)	C1B—N1B—H2B	108 (2)
H2A—N1A—H3A	111 (3)	H1B—N1B—H2B	109 (3)
N1A—C1A—C9A	109.6 (2)	C1B—N1B—H3B	107.0 (17)
N1A—C1A—C2A	111.5 (2)	H1B—N1B—H3B	112 (3)
C9A—C1A—C2A	107.3 (2)	H2B—N1B—H3B	108 (3)
N1A—C1A—H11A	109.5	N1B—C1B—C5B	109.8 (2)
C9A—C1A—H11A	109.5	N1B—C1B—C2B	110.2 (2)
C2A—C1A—H11A	109.5	C5B—C1B—C2B	108.0 (2)
C3A—C2A—C1A	117.4 (3)	N1B—C1B—H11B	109.6
C3A—C2A—H21A	108.0	C5B—C1B—H11B	109.6
C1A—C2A—H21A	108.0	C2B—C1B—H11B	109.6
C3A—C2A—H22A	108.0	C3B—C2B—C1B	116.5 (3)
C1A—C2A—H22A	108.0	C3B—C2B—H21B	108.2
H21A—C2A—H22A	107.2	C1B—C2B—H21B	108.2
C8A—C3A—C4A	117.5 (3)	C3B—C2B—H22B	108.2
C8A—C3A—C2A	121.0 (3)	C1B—C2B—H22B	108.2
C4A—C3A—C2A	121.5 (3)	H21B—C2B—H22B	107.3
C3A—C4A—C5A	121.0 (4)	C2B—C3B—C4B	110.8 (3)
C3A—C4A—H41A	119.5	C2B—C3B—H31B	109.5
C5A—C4A—H41A	119.5	C4B—C3B—H31B	109.5
C6A—C5A—C4A	120.3 (4)	C2B—C3B—H32B	109.5
C6A—C5A—H51A	119.8	C4B—C3B—H32B	109.5
C4A—C5A—H51A	119.8	H31B—C3B—H32B	108.1
C5A—C6A—C7A	119.7 (4)	C3B—C4B—H41B	109.5
C5A—C6A—H61A	120.1	C3B—C4B—H42B	109.5
C7A—C6A—H61A	120.1	H41B—C4B—H42B	109.5
C6A—C7A—C8A	120.0 (4)	C3B—C4B—H43B	109.5
C6A—C7A—H71A	120.0	H41B—C4B—H43B	109.5
C8A—C7A—H71A	120.0	H42B—C4B—H43B	109.5
C3A—C8A—C7A	121.4 (4)	O1B—C5B—O2B	125.8 (3)
C3A—C8A—H81A	119.3	O1B—C5B—C1B	117.0 (2)
C7A—C8A—H81A	119.3	O2B—C5B—C1B	117.0 (3)
N1A—C1A—C2A—C3A	−67.5 (3)	N1A—C1A—C9A—O1A	−31.8 (3)
C9A—C1A—C2A—C3A	172.5 (2)	C2A—C1A—C9A—O1A	89.4 (3)
C1A—C2A—C3A—C8A	−88.5 (4)	N1A—C1A—C9A—O2A	152.8 (2)
C1A—C2A—C3A—C4A	93.2 (4)	C2A—C1A—C9A—O2A	−86.0 (3)
C8A—C3A—C4A—C5A	−1.2 (6)	N1B—C1B—C2B—C3B	57.9 (3)
C2A—C3A—C4A—C5A	177.2 (3)	C5B—C1B—C2B—C3B	177.8 (3)
C3A—C4A—C5A—C6A	0.6 (6)	C1B—C2B—C3B—C4B	176.9 (3)
C4A—C5A—C6A—C7A	0.4 (7)	N1B—C1B—C5B—O1B	32.0 (3)
C5A—C6A—C7A—C8A	−0.7 (7)	C2B—C1B—C5B—O1B	−88.1 (3)
C4A—C3A—C8A—C7A	0.9 (6)	N1B—C1B—C5B—O2B	−152.6 (2)
C2A—C3A—C8A—C7A	−177.5 (4)	C2B—C1B—C5B—O2B	87.2 (3)
C6A—C7A—C8A—C3A	0.0 (7)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O2B	0.92 (2)	1.95 (3)	2.830 (3)	162 (3)
N1A—H3A···O2B^i	0.90 (2)	1.97 (3)	2.871 (3)	173 (3)
N1A—H2A···O1A^ii	0.93 (2)	1.85 (2)	2.780 (3)	173 (3)
N1B—H1B···O2A^iii	0.91 (2)	1.94 (3)	2.809 (3)	159 (3)
N1B—H3B···O1B^iv	0.95 (2)	1.80 (2)	2.743 (3)	171 (3)
N1B—H2B···O2A^v	0.91 (2)	1.94 (3)	2.835 (3)	168 (3)

Symmetry codes: (i) x−1, y, z; (ii) x+1/2, −y+1/2, −z; (iii) x, y+1, z; (iv) x−1/2, −y+3/2, −z; (v) x+1, y+1, z.

(III) L-Phenylalanine–D-methionine (1/1)

Crystal data

C9H11NO2·C5H11NO2S	F(000) = 336
Mr = 314.40	Dx = 1.368 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 4140 reflections
a = 10.110 (2) Å	θ = 2.1–25.0°
b = 4.7064 (9) Å	µ = 0.23 mm^−1
c = 16.686 (3) Å	T = 296 K
β = 106.663 (2)°	Flat needle, colourless
V = 760.6 (3) Å^3	1.24 × 0.1 × 0.02 mm
Z = 2

Data collection

Bruker APEXII CCD diffractometer	2580 independent reflections
Radiation source: fine-focus sealed tube	2406 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
Detector resolution: 8.3 pixels mm^-1	θmax = 25.0°, θmin = 2.1°
Sets of exposures each taken over 0.5° ω rotation scans	h = −12→12
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	k = −5→5
Tmin = 0.800, Tmax = 0.995	l = −19→19
5312 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.037	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.099	w = 1/[σ^2(Fo^2) + (0.0482P)^2 + 0.0887P] where P = (Fo^2 + 2Fc^2)/3
S = 1.18	(Δ/σ)max < 0.001
2580 reflections	Δρmax = 0.24 e Å^−3
208 parameters	Δρmin = −0.22 e Å^−3
7 restraints	Absolute structure: Flack (1983), 1082 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.00 (10)

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.

Refinement. Data were collected by measuring three sets of exposures with the detector set at 2θ = 29°, crystal-to-detector distance 6.00 cm. Refinement of F² against ALL reflections.

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

	x	y	z	Uiso*/Ueq
O1A	1.02662 (17)	0.6111 (5)	0.94043 (11)	0.0328 (4)
O2A	1.15498 (18)	0.3254 (4)	0.88695 (13)	0.0372 (5)
N1A	0.8114 (2)	0.2392 (5)	0.90004 (14)	0.0259 (5)
H1A	0.744 (3)	0.100 (6)	0.8811 (17)	0.039*
H2A	0.772 (3)	0.416 (6)	0.8981 (18)	0.039*
H3A	0.858 (3)	0.204 (7)	0.9544 (14)	0.039*
C1A	0.9139 (2)	0.2362 (6)	0.85202 (15)	0.0243 (6)
H11A	0.9395	0.0394	0.8443	0.029*
C2A	0.8565 (3)	0.3771 (7)	0.76664 (16)	0.0335 (7)
H21A	0.8235	0.5649	0.7752	0.040*
H22A	0.9317	0.4016	0.7419	0.040*
C3A	0.7421 (3)	0.2220 (6)	0.70527 (16)	0.0294 (6)
C4A	0.6054 (3)	0.2728 (7)	0.69934 (18)	0.0383 (7)
H41A	0.5827	0.4032	0.7351	0.046*
C5A	0.5017 (3)	0.1316 (9)	0.64071 (19)	0.0461 (7)
H51A	0.4099	0.1693	0.6372	0.055*
C6A	0.5325 (3)	−0.0625 (7)	0.58788 (19)	0.0454 (8)
H61A	0.4621	−0.1572	0.5487	0.054*
C7A	0.6677 (4)	−0.1165 (7)	0.59309 (19)	0.0469 (8)
H71A	0.6895	−0.2485	0.5574	0.056*
C8A	0.7717 (3)	0.0247 (6)	0.65126 (18)	0.0390 (7)
H81A	0.8632	−0.0133	0.6542	0.047*
C9A	1.0433 (2)	0.4028 (6)	0.89916 (15)	0.0235 (6)
S1B	0.08623 (7)	0.6219 (2)	0.63320 (4)	0.0437 (2)
O1B	0.52388 (19)	0.4513 (4)	0.93063 (12)	0.0347 (5)
O2B	0.64088 (17)	0.7423 (4)	0.87050 (13)	0.0365 (5)
N1B	0.3166 (2)	0.8280 (5)	0.90972 (15)	0.0264 (5)
H1B	0.366 (3)	0.867 (7)	0.9627 (14)	0.040*
H2B	0.274 (3)	0.666 (6)	0.9100 (18)	0.040*
H3B	0.252 (3)	0.963 (6)	0.8966 (19)	0.040*
C1B	0.4016 (2)	0.8308 (6)	0.85007 (16)	0.0244 (6)
H11B	0.4241	1.0273	0.8396	0.029*
C2B	0.3229 (2)	0.6906 (6)	0.76771 (15)	0.0285 (6)
H21B	0.3794	0.7005	0.7296	0.034*
H22B	0.3101	0.4913	0.7783	0.034*
C3B	0.1827 (3)	0.8196 (7)	0.72479 (17)	0.0357 (7)
H31B	0.1958	1.0127	0.7082	0.043*
H32B	0.1290	0.8280	0.7645	0.043*
C4B	0.1662 (4)	0.7323 (12)	0.5567 (2)	0.0769 (13)
H41B	0.1226	0.6396	0.5045	0.115*
H42B	0.2623	0.6827	0.5746	0.115*
H43B	0.1570	0.9344	0.5494	0.115*
C5B	0.5345 (2)	0.6651 (6)	0.88800 (15)	0.0247 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0323 (9)	0.0284 (10)	0.0356 (10)	−0.0043 (9)	0.0065 (8)	−0.0093 (10)
O2A	0.0206 (9)	0.0328 (11)	0.0586 (13)	−0.0004 (8)	0.0124 (9)	−0.0036 (10)
N1A	0.0227 (11)	0.0249 (12)	0.0286 (12)	−0.0018 (10)	0.0049 (9)	0.0036 (11)
C1A	0.0224 (12)	0.0223 (13)	0.0283 (13)	−0.0003 (11)	0.0076 (10)	−0.0003 (12)
C2A	0.0341 (15)	0.0375 (18)	0.0285 (14)	−0.0065 (13)	0.0082 (12)	0.0024 (13)
C3A	0.0322 (14)	0.0313 (15)	0.0225 (13)	−0.0009 (12)	0.0047 (11)	0.0059 (12)
C4A	0.0356 (15)	0.0421 (18)	0.0350 (16)	0.0055 (14)	0.0066 (13)	−0.0051 (14)
C5A	0.0282 (14)	0.059 (2)	0.0451 (16)	−0.0018 (17)	0.0015 (12)	0.001 (2)
C6A	0.0464 (19)	0.047 (2)	0.0327 (16)	−0.0135 (16)	−0.0044 (14)	0.0005 (16)
C7A	0.064 (2)	0.0405 (19)	0.0343 (16)	0.0017 (16)	0.0115 (15)	−0.0094 (15)
C8A	0.0352 (15)	0.047 (2)	0.0326 (15)	0.0033 (14)	0.0070 (13)	−0.0019 (14)
C9A	0.0246 (13)	0.0192 (15)	0.0245 (13)	0.0001 (11)	0.0033 (11)	0.0063 (12)
S1B	0.0360 (4)	0.0576 (5)	0.0332 (4)	−0.0070 (4)	0.0032 (3)	−0.0072 (4)
O1B	0.0334 (10)	0.0318 (12)	0.0360 (11)	0.0047 (9)	0.0052 (9)	0.0064 (10)
O2B	0.0215 (9)	0.0330 (11)	0.0557 (13)	−0.0019 (8)	0.0123 (9)	−0.0010 (10)
N1B	0.0248 (12)	0.0248 (13)	0.0284 (12)	0.0007 (10)	0.0057 (10)	−0.0049 (11)
C1B	0.0252 (13)	0.0168 (13)	0.0318 (14)	0.0016 (11)	0.0093 (11)	0.0030 (12)
C2B	0.0288 (13)	0.0272 (18)	0.0278 (13)	0.0043 (11)	0.0054 (11)	0.0007 (12)
C3B	0.0302 (15)	0.0418 (18)	0.0310 (15)	0.0037 (13)	0.0022 (12)	−0.0097 (14)
C4B	0.066 (2)	0.125 (4)	0.0393 (19)	−0.019 (3)	0.0147 (17)	−0.001 (2)
C5B	0.0235 (12)	0.0217 (17)	0.0261 (13)	−0.0007 (12)	0.0025 (10)	−0.0045 (12)

Geometric parameters (Å, º)

O1A—C9A	1.237 (3)	C7A—H71A	0.9300
O2A—C9A	1.257 (3)	C8A—H81A	0.9300
N1A—C1A	1.481 (3)	S1B—C4B	1.774 (4)
N1A—H1A	0.93 (2)	S1B—C3B	1.816 (3)
N1A—H2A	0.92 (2)	O1B—C5B	1.254 (3)
N1A—H3A	0.91 (2)	O2B—C5B	1.247 (3)
C1A—C2A	1.527 (4)	N1B—C1B	1.491 (3)
C1A—C9A	1.535 (4)	N1B—H1B	0.90 (2)
C1A—H11A	0.9800	N1B—H2B	0.88 (2)
C2A—C3A	1.497 (4)	N1B—H3B	0.89 (2)
C2A—H21A	0.9700	C1B—C5B	1.525 (3)
C2A—H22A	0.9700	C1B—C2B	1.526 (3)
C3A—C4A	1.378 (4)	C1B—H11B	0.9800
C3A—C8A	1.385 (4)	C2B—C3B	1.519 (4)
C4A—C5A	1.381 (4)	C2B—H21B	0.9700
C4A—H41A	0.9300	C2B—H22B	0.9700
C5A—C6A	1.366 (5)	C3B—H31B	0.9700
C5A—H51A	0.9300	C3B—H32B	0.9700
C6A—C7A	1.368 (5)	C4B—H41B	0.9600
C6A—H61A	0.9300	C4B—H42B	0.9600
C7A—C8A	1.380 (4)	C4B—H43B	0.9600
C1A—N1A—H1A	111.4 (18)	O1A—C9A—C1A	117.2 (2)
C1A—N1A—H2A	110.5 (19)	O2A—C9A—C1A	116.2 (2)
H1A—N1A—H2A	111 (3)	C4B—S1B—C3B	102.12 (17)
C1A—N1A—H3A	107.2 (17)	C1B—N1B—H1B	113.2 (18)
H1A—N1A—H3A	109 (3)	C1B—N1B—H2B	113 (2)
H2A—N1A—H3A	107 (3)	H1B—N1B—H2B	108 (3)
N1A—C1A—C2A	111.3 (2)	C1B—N1B—H3B	111 (2)
N1A—C1A—C9A	110.1 (2)	H1B—N1B—H3B	105 (3)
C2A—C1A—C9A	107.2 (2)	H2B—N1B—H3B	107 (3)
N1A—C1A—H11A	109.4	N1B—C1B—C5B	109.1 (2)
C2A—C1A—H11A	109.4	N1B—C1B—C2B	110.2 (2)
C9A—C1A—H11A	109.4	C5B—C1B—C2B	108.8 (2)
C3A—C2A—C1A	116.0 (2)	N1B—C1B—H11B	109.6
C3A—C2A—H21A	108.3	C5B—C1B—H11B	109.6
C1A—C2A—H21A	108.3	C2B—C1B—H11B	109.6
C3A—C2A—H22A	108.3	C3B—C2B—C1B	115.3 (2)
C1A—C2A—H22A	108.3	C3B—C2B—H21B	108.5
H21A—C2A—H22A	107.4	C1B—C2B—H21B	108.5
C4A—C3A—C8A	117.9 (3)	C3B—C2B—H22B	108.5
C4A—C3A—C2A	121.8 (3)	C1B—C2B—H22B	108.5
C8A—C3A—C2A	120.2 (3)	H21B—C2B—H22B	107.5
C3A—C4A—C5A	120.6 (3)	C2B—C3B—S1B	113.29 (19)
C3A—C4A—H41A	119.7	C2B—C3B—H31B	108.9
C5A—C4A—H41A	119.7	S1B—C3B—H31B	108.9
C6A—C5A—C4A	120.8 (3)	C2B—C3B—H32B	108.9
C6A—C5A—H51A	119.6	S1B—C3B—H32B	108.9
C4A—C5A—H51A	119.6	H31B—C3B—H32B	107.7
C5A—C6A—C7A	119.4 (3)	S1B—C4B—H41B	109.5
C5A—C6A—H61A	120.3	S1B—C4B—H42B	109.5
C7A—C6A—H61A	120.3	H41B—C4B—H42B	109.5
C6A—C7A—C8A	120.1 (3)	S1B—C4B—H43B	109.5
C6A—C7A—H71A	120.0	H41B—C4B—H43B	109.5
C8A—C7A—H71A	120.0	H42B—C4B—H43B	109.5
C7A—C8A—C3A	121.2 (3)	O2B—C5B—O1B	125.9 (2)
C7A—C8A—H81A	119.4	O2B—C5B—C1B	118.0 (2)
C3A—C8A—H81A	119.4	O1B—C5B—C1B	115.9 (2)
O1A—C9A—O2A	126.3 (2)
N1A—C1A—C2A—C3A	−68.4 (3)	N1A—C1A—C9A—O1A	−33.7 (3)
C9A—C1A—C2A—C3A	171.1 (2)	C2A—C1A—C9A—O1A	87.5 (3)
C1A—C2A—C3A—C4A	91.2 (3)	N1A—C1A—C9A—O2A	151.3 (2)
C1A—C2A—C3A—C8A	−90.0 (3)	C2A—C1A—C9A—O2A	−87.5 (3)
C8A—C3A—C4A—C5A	−0.5 (5)	N1B—C1B—C2B—C3B	56.5 (3)
C2A—C3A—C4A—C5A	178.4 (3)	C5B—C1B—C2B—C3B	176.1 (2)
C3A—C4A—C5A—C6A	0.5 (5)	C1B—C2B—C3B—S1B	−173.88 (19)
C4A—C5A—C6A—C7A	−0.2 (5)	C4B—S1B—C3B—C2B	−78.3 (3)
C5A—C6A—C7A—C8A	−0.1 (5)	N1B—C1B—C5B—O2B	−148.0 (2)
C6A—C7A—C8A—C3A	0.1 (5)	C2B—C1B—C5B—O2B	91.8 (3)
C4A—C3A—C8A—C7A	0.2 (4)	N1B—C1B—C5B—O1B	36.0 (3)
C2A—C3A—C8A—C7A	−178.7 (3)	C2B—C1B—C5B—O1B	−84.3 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O2B^i	0.93 (2)	1.96 (3)	2.863 (3)	162 (3)
N1A—H2A···O2B	0.92 (2)	2.00 (2)	2.887 (3)	163 (3)
N1A—H3A···O1A^ii	0.91 (2)	1.86 (2)	2.762 (3)	172 (3)
N1B—H1B···O1B^iii	0.90 (2)	1.85 (2)	2.752 (3)	176 (3)
N1B—H2B···O2A^iv	0.88 (2)	1.98 (2)	2.838 (3)	168 (3)
N1B—H3B···O2A^v	0.89 (2)	1.95 (2)	2.817 (3)	163 (3)

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

(IV) L-Phenylalanine–D-leucine (1/1)

Crystal data

C9H11NO2·C6H13NO2	F(000) = 320
Mr = 296.36	Dx = 1.259 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 2870 reflections
a = 5.1861 (5) Å	θ = 2.7–25.0°
b = 29.698 (3) Å	µ = 0.09 mm^−1
c = 5.4158 (5) Å	T = 296 K
β = 110.372 (1)°	Plate, colourless
V = 781.95 (13) Å^3	0.3 × 0.2 × 0.06 mm
Z = 2

Data collection

Bruker APEXII CCD diffractometer	1411 independent reflections
Radiation source: fine-focus sealed tube	1269 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
Detector resolution: 8.3 pixels mm^-1	θmax = 25.0°, θmin = 2.7°
Sets of exposures each taken over 0.5° ω rotation scans	h = −6→6
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	k = −35→35
Tmin = 0.909, Tmax = 0.995	l = −6→6
7778 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.089	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0438P)^2 + 0.1739P] where P = (Fo^2 + 2Fc^2)/3
1411 reflections	(Δ/σ)max < 0.001
208 parameters	Δρmax = 0.14 e Å^−3
12 restraints	Δρmin = −0.16 e Å^−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.

Refinement. Data were collected by measuring four sets of exposures with the detector set at 2θ = 29°, crystal-to-detector distance 6.00 cm. Refinement of F² against ALL reflections.

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

	x	y	z	Uiso*/Ueq
O1A	0.1937 (4)	0.65841 (9)	0.6354 (4)	0.0413 (7)
O2A	0.6475 (4)	0.65012 (8)	0.7847 (4)	0.0356 (5)
N1A	0.2052 (5)	0.67014 (10)	1.1385 (5)	0.0303 (6)
H1A	0.240 (7)	0.7000 (9)	1.111 (7)	0.045*
H2A	0.210 (7)	0.6659 (12)	1.307 (5)	0.045*
H3A	0.034 (5)	0.6623 (12)	1.038 (6)	0.045*
C1A	0.4093 (5)	0.63963 (10)	1.0854 (5)	0.0275 (6)
H11A	0.5913	0.6446	1.2189	0.033*
C2A	0.3164 (7)	0.59156 (11)	1.1079 (7)	0.0416 (8)
H21A	0.3074	0.5877	1.2825	0.050*
H22A	0.1314	0.5878	0.9823	0.050*
C3A	0.4919 (7)	0.55507 (11)	1.0625 (6)	0.0425 (8)
C4A	0.7301 (9)	0.54142 (17)	1.2477 (11)	0.0857 (16)
H41A	0.7924	0.5561	1.4096	0.103*
C5A	0.8839 (10)	0.50614 (19)	1.2023 (12)	0.107 (2)
H51A	1.0491	0.4982	1.3320	0.128*
C6A	0.7980 (10)	0.48372 (15)	0.9764 (10)	0.0826 (15)
H61A	0.8957	0.4590	0.9504	0.099*
C7A	0.5713 (14)	0.4972 (2)	0.7897 (12)	0.122 (2)
H71A	0.5134	0.4826	0.6274	0.147*
C8A	0.4192 (12)	0.53240 (18)	0.8317 (9)	0.1005 (19)
H81A	0.2601	0.5410	0.6958	0.121*
C9A	0.4199 (5)	0.65037 (10)	0.8121 (5)	0.0254 (6)
O1B	0.8063 (4)	0.74386 (8)	1.1112 (4)	0.0380 (6)
O2B	0.3534 (4)	0.75444 (7)	0.9634 (4)	0.0351 (5)
N1B	0.8026 (5)	0.73490 (10)	0.6116 (5)	0.0288 (6)
H1B	0.767 (7)	0.7060 (9)	0.641 (7)	0.043*
H2B	0.979 (5)	0.7419 (12)	0.712 (6)	0.043*
H3B	0.808 (7)	0.7377 (12)	0.441 (5)	0.043*
C1B	0.5946 (6)	0.76440 (10)	0.6625 (5)	0.0264 (6)
H11B	0.4140	0.7592	0.5273	0.032*
C2B	0.6793 (7)	0.81324 (11)	0.6502 (7)	0.0382 (8)
H21B	0.7254	0.8172	0.4926	0.046*
H22B	0.8447	0.8190	0.8004	0.046*
C3B	0.4638 (8)	0.84833 (12)	0.6484 (8)	0.0508 (9)
H31B	0.3792	0.8392	0.7765	0.061*
C4B	0.2403 (9)	0.85166 (17)	0.3812 (9)	0.0764 (13)
H41B	0.1094	0.8742	0.3861	0.115*
H42B	0.1493	0.8231	0.3356	0.115*
H43B	0.3202	0.8598	0.2519	0.115*
C5B	0.6026 (13)	0.89361 (16)	0.7332 (12)	0.0970 (18)
H51B	0.4668	0.9157	0.7310	0.145*
H52B	0.6938	0.9025	0.6142	0.145*
H53B	0.7351	0.8912	0.9082	0.145*
C6B	0.5822 (5)	0.75299 (9)	0.9353 (5)	0.0250 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0333 (13)	0.0715 (18)	0.0207 (11)	0.0090 (11)	0.0113 (9)	0.0068 (11)
O2A	0.0303 (11)	0.0483 (13)	0.0349 (11)	−0.0014 (10)	0.0198 (8)	0.0022 (10)
N1A	0.0336 (15)	0.0400 (15)	0.0189 (13)	0.0047 (12)	0.0112 (11)	0.0025 (11)
C1A	0.0251 (14)	0.0379 (16)	0.0210 (14)	0.0035 (12)	0.0099 (11)	0.0029 (12)
C2A	0.0513 (19)	0.0409 (19)	0.0432 (18)	0.0043 (15)	0.0297 (16)	0.0083 (15)
C3A	0.0499 (19)	0.0365 (17)	0.0487 (19)	0.0022 (14)	0.0268 (16)	0.0094 (16)
C4A	0.062 (3)	0.075 (3)	0.098 (4)	0.014 (2)	0.000 (2)	−0.033 (3)
C5A	0.065 (3)	0.086 (4)	0.139 (5)	0.034 (3)	−0.004 (3)	−0.023 (4)
C6A	0.090 (3)	0.050 (3)	0.123 (4)	0.013 (2)	0.057 (3)	−0.010 (3)
C7A	0.153 (6)	0.108 (5)	0.091 (4)	0.059 (4)	0.024 (4)	−0.032 (3)
C8A	0.122 (4)	0.103 (4)	0.064 (3)	0.060 (4)	0.015 (3)	−0.013 (3)
C9A	0.0295 (14)	0.0279 (14)	0.0222 (14)	−0.0008 (12)	0.0132 (11)	−0.0004 (12)
O1B	0.0335 (12)	0.0623 (17)	0.0215 (11)	0.0088 (11)	0.0137 (10)	0.0058 (10)
O2B	0.0292 (11)	0.0488 (13)	0.0323 (11)	−0.0022 (9)	0.0169 (9)	0.0010 (10)
N1B	0.0318 (15)	0.0390 (15)	0.0197 (13)	0.0043 (12)	0.0141 (12)	0.0031 (12)
C1B	0.0269 (14)	0.0334 (15)	0.0195 (14)	0.0013 (12)	0.0087 (11)	0.0025 (12)
C2B	0.0405 (17)	0.0400 (19)	0.0372 (17)	−0.0025 (13)	0.0174 (14)	0.0065 (14)
C3B	0.066 (2)	0.0402 (19)	0.055 (2)	0.0086 (18)	0.0311 (19)	0.0106 (17)
C4B	0.065 (3)	0.072 (3)	0.084 (3)	0.023 (2)	0.016 (2)	0.018 (2)
C5B	0.120 (4)	0.045 (2)	0.116 (4)	0.003 (3)	0.027 (4)	−0.006 (3)
C6B	0.0275 (14)	0.0265 (14)	0.0232 (14)	−0.0002 (11)	0.0118 (11)	−0.0022 (11)

Geometric parameters (Å, º)

O1A—C9A	1.252 (3)	C8A—H81A	0.9300
O2A—C9A	1.240 (3)	O1B—C6B	1.250 (3)
N1A—C1A	1.495 (4)	O2B—C6B	1.248 (3)
N1A—H1A	0.93 (3)	N1B—C1B	1.488 (4)
N1A—H2A	0.91 (2)	N1B—H1B	0.90 (3)
N1A—H3A	0.90 (2)	N1B—H2B	0.91 (2)
C1A—C2A	1.525 (4)	N1B—H3B	0.94 (2)
C1A—C9A	1.534 (3)	C1B—C2B	1.524 (4)
C1A—H11A	0.9800	C1B—C6B	1.539 (4)
C2A—C3A	1.490 (4)	C1B—H11B	0.9800
C2A—H21A	0.9700	C2B—C3B	1.526 (5)
C2A—H22A	0.9700	C2B—H21B	0.9700
C3A—C8A	1.353 (5)	C2B—H22B	0.9700
C3A—C4A	1.354 (5)	C3B—C4B	1.510 (6)
C4A—C5A	1.389 (6)	C3B—C5B	1.519 (6)
C4A—H41A	0.9300	C3B—H31B	0.9800
C5A—C6A	1.326 (6)	C4B—H41B	0.9600
C5A—H51A	0.9300	C4B—H42B	0.9600
C6A—C7A	1.318 (6)	C4B—H43B	0.9600
C6A—H61A	0.9300	C5B—H51B	0.9600
C7A—C8A	1.376 (6)	C5B—H52B	0.9600
C7A—H71A	0.9300	C5B—H53B	0.9600
C1A—N1A—H1A	111 (2)	C1B—N1B—H1B	109 (2)
C1A—N1A—H2A	110 (2)	C1B—N1B—H2B	113 (2)
H1A—N1A—H2A	111 (3)	H1B—N1B—H2B	110 (3)
C1A—N1A—H3A	110 (2)	C1B—N1B—H3B	114 (2)
H1A—N1A—H3A	111 (3)	H1B—N1B—H3B	110 (3)
H2A—N1A—H3A	104 (3)	H2B—N1B—H3B	102 (3)
N1A—C1A—C2A	106.7 (2)	N1B—C1B—C2B	108.3 (2)
N1A—C1A—C9A	109.0 (2)	N1B—C1B—C6B	108.9 (2)
C2A—C1A—C9A	113.0 (2)	C2B—C1B—C6B	111.1 (2)
N1A—C1A—H11A	109.4	N1B—C1B—H11B	109.5
C2A—C1A—H11A	109.4	C2B—C1B—H11B	109.5
C9A—C1A—H11A	109.4	C6B—C1B—H11B	109.5
C3A—C2A—C1A	116.1 (2)	C1B—C2B—C3B	115.4 (3)
C3A—C2A—H21A	108.3	C1B—C2B—H21B	108.4
C1A—C2A—H21A	108.3	C3B—C2B—H21B	108.4
C3A—C2A—H22A	108.3	C1B—C2B—H22B	108.4
C1A—C2A—H22A	108.3	C3B—C2B—H22B	108.4
H21A—C2A—H22A	107.4	H21B—C2B—H22B	107.5
C8A—C3A—C4A	115.1 (4)	C4B—C3B—C5B	110.9 (4)
C8A—C3A—C2A	121.7 (3)	C4B—C3B—C2B	111.5 (3)
C4A—C3A—C2A	123.2 (3)	C5B—C3B—C2B	109.5 (4)
C3A—C4A—C5A	121.8 (4)	C4B—C3B—H31B	108.3
C3A—C4A—H41A	119.1	C5B—C3B—H31B	108.3
C5A—C4A—H41A	119.1	C2B—C3B—H31B	108.3
C6A—C5A—C4A	120.8 (4)	C3B—C4B—H41B	109.5
C6A—C5A—H51A	119.6	C3B—C4B—H42B	109.5
C4A—C5A—H51A	119.6	H41B—C4B—H42B	109.5
C7A—C6A—C5A	118.6 (5)	C3B—C4B—H43B	109.5
C7A—C6A—H61A	120.7	H41B—C4B—H43B	109.5
C5A—C6A—H61A	120.7	H42B—C4B—H43B	109.5
C6A—C7A—C8A	120.9 (5)	C3B—C5B—H51B	109.5
C6A—C7A—H71A	119.6	C3B—C5B—H52B	109.5
C8A—C7A—H71A	119.6	H51B—C5B—H52B	109.5
C3A—C8A—C7A	122.7 (5)	C3B—C5B—H53B	109.5
C3A—C8A—H81A	118.7	H51B—C5B—H53B	109.5
C7A—C8A—H81A	118.7	H52B—C5B—H53B	109.5
O2A—C9A—O1A	126.0 (2)	O2B—C6B—O1B	125.9 (2)
O2A—C9A—C1A	118.0 (2)	O2B—C6B—C1B	118.0 (2)
O1A—C9A—C1A	116.0 (2)	O1B—C6B—C1B	116.2 (2)
N1A—C1A—C2A—C3A	−179.9 (3)	N1A—C1A—C9A—O2A	140.2 (3)
C9A—C1A—C2A—C3A	60.4 (3)	C2A—C1A—C9A—O2A	−101.4 (3)
C1A—C2A—C3A—C8A	−101.7 (5)	N1A—C1A—C9A—O1A	−40.2 (3)
C1A—C2A—C3A—C4A	79.8 (5)	C2A—C1A—C9A—O1A	78.2 (3)
C8A—C3A—C4A—C5A	−1.0 (8)	N1B—C1B—C2B—C3B	169.4 (3)
C2A—C3A—C4A—C5A	177.6 (5)	C6B—C1B—C2B—C3B	−71.1 (3)
C3A—C4A—C5A—C6A	−1.7 (10)	C1B—C2B—C3B—C4B	−76.9 (4)
C4A—C5A—C6A—C7A	3.8 (10)	C1B—C2B—C3B—C5B	159.9 (4)
C5A—C6A—C7A—C8A	−3.0 (11)	N1B—C1B—C6B—O2B	−143.5 (3)
C4A—C3A—C8A—C7A	1.8 (9)	C2B—C1B—C6B—O2B	97.3 (3)
C2A—C3A—C8A—C7A	−176.8 (6)	N1B—C1B—C6B—O1B	37.8 (3)
C6A—C7A—C8A—C3A	0.2 (11)	C2B—C1B—C6B—O1B	−81.4 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O2B	0.93 (3)	1.98 (3)	2.875 (4)	161 (3)
N1A—H2A···O1A^i	0.91 (2)	1.82 (3)	2.735 (3)	176 (3)
N1A—H3A···O2A^ii	0.90 (2)	2.03 (3)	2.921 (3)	174 (3)
N1B—H1B···O2A	0.90 (3)	2.02 (3)	2.896 (4)	163 (3)
N1B—H2B···O2B^iii	0.91 (2)	1.98 (3)	2.887 (3)	174 (3)
N1B—H3B···O1B^iv	0.94 (2)	1.79 (2)	2.729 (3)	178 (3)

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

(V) L-Phenylalanine–D-isoleucine (1/1)

Crystal data

C9H11NO2·C6H13NO2	Z = 1
Mr = 296.36	F(000) = 160
Triclinic, P1	Dx = 1.279 Mg m^−3
Hall symbol: P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.2317 (12) Å	Cell parameters from 3065 reflections
b = 5.4232 (12) Å	θ = 2.8–25.0°
c = 14.459 (3) Å	µ = 0.09 mm^−1
α = 85.936 (3)°	T = 296 K
β = 85.343 (3)°	Plate, colourless
γ = 70.424 (2)°	0.32 × 0.18 × 0.03 mm
V = 384.83 (15) Å^3

Data collection

Bruker APEXII CCD diffractometer	1359 independent reflections
Radiation source: fine-focus sealed tube	1054 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
Detector resolution: 8.3 pixels mm^-1	θmax = 25.0°, θmin = 2.8°
Sets of exposures each taken over 0.5° ω rotation scans	h = −6→6
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	k = −6→6
Tmin = 0.762, Tmax = 0.997	l = −17→17
2821 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.099	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0544P)^2 + 0.0052P] where P = (Fo^2 + 2Fc^2)/3
1359 reflections	(Δ/σ)max < 0.001
210 parameters	Δρmax = 0.17 e Å^−3
9 restraints	Δρmin = −0.16 e Å^−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.

Refinement. Data were collected by measuring three sets of exposures with the detector set at 2θ = 29°, crystal-to-detector distance 6.00 cm. Refinement of F² against ALL reflections.

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

	x	y	z	Uiso*/Ueq
O1A	0.5376 (5)	−0.0492 (5)	0.5393 (2)	0.0421 (9)
O2A	0.0926 (5)	0.0988 (6)	0.5197 (2)	0.0382 (8)
N1A	0.5316 (7)	0.4467 (7)	0.5611 (3)	0.0314 (9)
H1A	0.496 (9)	0.404 (9)	0.622 (2)	0.047*
H2A	0.529 (10)	0.615 (6)	0.552 (3)	0.047*
H3A	0.712 (6)	0.340 (8)	0.546 (3)	0.047*
C1A	0.3369 (9)	0.4021 (8)	0.5000 (3)	0.0323 (11)
H11A	0.1569	0.5330	0.5112	0.039*
C2A	0.4435 (9)	0.4386 (9)	0.4000 (3)	0.0431 (13)
H21A	0.4543	0.6140	0.3917	0.052*
H22A	0.6271	0.3165	0.3918	0.052*
C3A	0.2821 (9)	0.4015 (9)	0.3247 (3)	0.0449 (11)
C4A	0.0499 (11)	0.5901 (14)	0.2978 (4)	0.0789 (19)
H41A	−0.0151	0.7472	0.3279	0.095*
C5A	−0.0921 (13)	0.5497 (17)	0.2251 (5)	0.097 (2)
H51A	−0.2523	0.6782	0.2083	0.116*
C6A	0.0020 (14)	0.3276 (16)	0.1800 (4)	0.085 (2)
H61A	−0.0884	0.3055	0.1301	0.102*
C7A	0.225 (2)	0.1373 (17)	0.2061 (6)	0.121 (3)
H71A	0.2872	−0.0195	0.1758	0.146*
C8A	0.3632 (15)	0.1757 (13)	0.2794 (5)	0.101 (2)
H81A	0.5170	0.0410	0.2977	0.121*
C9A	0.3195 (8)	0.1261 (8)	0.5215 (3)	0.0277 (10)
O1B	−0.0869 (5)	0.3990 (5)	0.7093 (2)	0.0371 (8)
O2B	0.3513 (5)	0.2610 (6)	0.7389 (2)	0.0355 (8)
N1B	−0.1008 (7)	−0.0869 (7)	0.6984 (3)	0.0304 (9)
H1B	−0.075 (9)	−0.043 (9)	0.635 (2)	0.046*
H2B	−0.273 (6)	0.019 (8)	0.720 (3)	0.046*
H3B	−0.101 (10)	−0.256 (6)	0.706 (3)	0.046*
C1B	0.1225 (7)	−0.0544 (8)	0.7494 (3)	0.0255 (10)
H11B	0.2948	−0.1748	0.7239	0.031*
C2B	0.0936 (8)	−0.1298 (9)	0.8528 (3)	0.0338 (10)
H21B	0.0230	−0.2766	0.8575	0.041*
C3B	0.3671 (9)	−0.2258 (10)	0.8952 (3)	0.0501 (12)
H31B	0.4938	−0.3550	0.8556	0.060*
H32B	0.4343	−0.0796	0.8960	0.060*
C4B	0.3637 (13)	−0.3460 (13)	0.9926 (4)	0.084 (2)
H41B	0.5466	−0.4210	1.0116	0.127*
H42B	0.2817	−0.4803	0.9939	0.127*
H43B	0.2609	−0.2130	1.0343	0.127*
C5B	−0.1114 (9)	0.0922 (9)	0.9064 (3)	0.0453 (11)
H51B	−0.2767	0.1580	0.8746	0.068*
H52B	−0.0376	0.2307	0.9107	0.068*
H53B	−0.1488	0.0274	0.9678	0.068*
C6B	0.1290 (8)	0.2251 (9)	0.7304 (3)	0.0268 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0362 (18)	0.0201 (18)	0.072 (2)	−0.0120 (16)	−0.0090 (16)	0.0022 (16)
O2A	0.0310 (17)	0.0360 (18)	0.0525 (19)	−0.0183 (15)	0.0000 (14)	−0.0017 (15)
N1A	0.037 (2)	0.024 (2)	0.037 (2)	−0.0160 (19)	−0.0069 (17)	0.0036 (19)
C1A	0.032 (2)	0.029 (3)	0.041 (3)	−0.017 (2)	−0.008 (2)	0.002 (2)
C2A	0.053 (3)	0.047 (3)	0.039 (3)	−0.030 (2)	−0.010 (2)	0.008 (2)
C3A	0.055 (3)	0.051 (3)	0.036 (2)	−0.029 (2)	−0.004 (2)	0.006 (2)
C4A	0.061 (4)	0.095 (5)	0.065 (4)	0.001 (3)	−0.016 (3)	−0.024 (4)
C5A	0.065 (4)	0.142 (7)	0.068 (4)	−0.007 (4)	−0.030 (3)	−0.013 (4)
C6A	0.080 (4)	0.134 (7)	0.060 (4)	−0.056 (5)	−0.017 (3)	−0.007 (4)
C7A	0.156 (8)	0.104 (6)	0.110 (6)	−0.034 (6)	−0.063 (6)	−0.030 (5)
C8A	0.134 (6)	0.066 (4)	0.092 (5)	−0.005 (4)	−0.066 (5)	−0.015 (4)
C9A	0.031 (2)	0.021 (3)	0.032 (2)	−0.009 (2)	0.0037 (19)	−0.006 (2)
O1B	0.0338 (19)	0.0224 (18)	0.057 (2)	−0.0098 (16)	−0.0133 (15)	0.0021 (15)
O2B	0.0307 (17)	0.0350 (18)	0.0482 (18)	−0.0205 (15)	−0.0036 (13)	0.0002 (15)
N1B	0.032 (2)	0.022 (2)	0.041 (2)	−0.0128 (19)	−0.0084 (18)	−0.0009 (19)
C1B	0.021 (2)	0.022 (2)	0.033 (2)	−0.0058 (19)	−0.0039 (17)	−0.004 (2)
C2B	0.034 (2)	0.031 (2)	0.040 (3)	−0.0162 (19)	−0.0051 (19)	0.0036 (19)
C3B	0.050 (3)	0.051 (3)	0.047 (3)	−0.013 (2)	−0.013 (2)	0.006 (2)
C4B	0.089 (4)	0.091 (5)	0.049 (3)	0.002 (4)	−0.016 (3)	0.011 (3)
C5B	0.048 (3)	0.045 (3)	0.045 (3)	−0.017 (2)	0.001 (2)	−0.004 (2)
C6B	0.029 (2)	0.028 (3)	0.028 (2)	−0.016 (2)	0.0008 (19)	−0.004 (2)

Geometric parameters (Å, º)

O1A—C9A	1.248 (5)	C8A—H81A	0.9300
O2A—C9A	1.247 (5)	O1B—C6B	1.249 (5)
N1A—C1A	1.489 (6)	O2B—C6B	1.258 (5)
N1A—H1A	0.91 (3)	N1B—C1B	1.495 (5)
N1A—H2A	0.91 (3)	N1B—H1B	0.94 (3)
N1A—H3A	0.94 (3)	N1B—H2B	0.93 (3)
C1A—C2A	1.532 (6)	N1B—H3B	0.92 (3)
C1A—C9A	1.538 (6)	C1B—C2B	1.531 (6)
C1A—H11A	0.9800	C1B—C6B	1.533 (6)
C2A—C3A	1.494 (6)	C1B—H11B	0.9800
C2A—H21A	0.9700	C2B—C3B	1.514 (6)
C2A—H22A	0.9700	C2B—C5B	1.527 (6)
C3A—C8A	1.353 (8)	C2B—H21B	0.9800
C3A—C4A	1.364 (7)	C3B—C4B	1.511 (7)
C4A—C5A	1.405 (9)	C3B—H31B	0.9700
C4A—H41A	0.9300	C3B—H32B	0.9700
C5A—C6A	1.333 (10)	C4B—H41B	0.9600
C5A—H51A	0.9300	C4B—H42B	0.9600
C6A—C7A	1.332 (9)	C4B—H43B	0.9600
C6A—H61A	0.9300	C5B—H51B	0.9600
C7A—C8A	1.396 (9)	C5B—H52B	0.9600
C7A—H71A	0.9300	C5B—H53B	0.9600
C1A—N1A—H1A	111 (3)	C1B—N1B—H1B	109 (3)
C1A—N1A—H2A	109 (3)	C1B—N1B—H2B	113 (3)
H1A—N1A—H2A	112 (5)	H1B—N1B—H2B	108 (4)
C1A—N1A—H3A	112 (3)	C1B—N1B—H3B	110 (3)
H1A—N1A—H3A	106 (4)	H1B—N1B—H3B	110 (5)
H2A—N1A—H3A	107 (4)	H2B—N1B—H3B	106 (4)
N1A—C1A—C2A	106.3 (3)	N1B—C1B—C2B	110.8 (3)
N1A—C1A—C9A	109.6 (3)	N1B—C1B—C6B	109.2 (3)
C2A—C1A—C9A	112.5 (4)	C2B—C1B—C6B	113.6 (3)
N1A—C1A—H11A	109.5	N1B—C1B—H11B	107.7
C2A—C1A—H11A	109.5	C2B—C1B—H11B	107.7
C9A—C1A—H11A	109.5	C6B—C1B—H11B	107.7
C3A—C2A—C1A	116.6 (3)	C3B—C2B—C5B	111.9 (4)
C3A—C2A—H21A	108.1	C3B—C2B—C1B	111.1 (3)
C1A—C2A—H21A	108.1	C5B—C2B—C1B	112.1 (4)
C3A—C2A—H22A	108.1	C3B—C2B—H21B	107.1
C1A—C2A—H22A	108.1	C5B—C2B—H21B	107.1
H21A—C2A—H22A	107.3	C1B—C2B—H21B	107.1
C8A—C3A—C4A	116.7 (5)	C4B—C3B—C2B	114.5 (4)
C8A—C3A—C2A	120.7 (5)	C4B—C3B—H31B	108.6
C4A—C3A—C2A	122.6 (4)	C2B—C3B—H31B	108.6
C3A—C4A—C5A	120.7 (6)	C4B—C3B—H32B	108.6
C3A—C4A—H41A	119.6	C2B—C3B—H32B	108.6
C5A—C4A—H41A	119.6	H31B—C3B—H32B	107.6
C6A—C5A—C4A	120.2 (6)	C3B—C4B—H41B	109.5
C6A—C5A—H51A	119.9	C3B—C4B—H42B	109.5
C4A—C5A—H51A	119.9	H41B—C4B—H42B	109.5
C7A—C6A—C5A	120.4 (6)	C3B—C4B—H43B	109.5
C7A—C6A—H61A	119.8	H41B—C4B—H43B	109.5
C5A—C6A—H61A	119.8	H42B—C4B—H43B	109.5
C6A—C7A—C8A	119.3 (7)	C2B—C5B—H51B	109.5
C6A—C7A—H71A	120.4	C2B—C5B—H52B	109.5
C8A—C7A—H71A	120.4	H51B—C5B—H52B	109.5
C3A—C8A—C7A	122.5 (6)	C2B—C5B—H53B	109.5
C3A—C8A—H81A	118.8	H51B—C5B—H53B	109.5
C7A—C8A—H81A	118.8	H52B—C5B—H53B	109.5
O2A—C9A—O1A	126.5 (4)	O1B—C6B—O2B	125.4 (4)
O2A—C9A—C1A	117.7 (4)	O1B—C6B—C1B	117.5 (3)
O1A—C9A—C1A	115.8 (4)	O2B—C6B—C1B	117.1 (4)
N1A—C1A—C2A—C3A	179.5 (4)	C2A—C1A—C9A—O2A	−99.9 (5)
C9A—C1A—C2A—C3A	59.6 (5)	N1A—C1A—C9A—O1A	−37.8 (5)
C1A—C2A—C3A—C8A	−101.1 (6)	C2A—C1A—C9A—O1A	80.2 (4)
C1A—C2A—C3A—C4A	79.4 (6)	N1B—C1B—C2B—C3B	152.2 (4)
C8A—C3A—C4A—C5A	−1.2 (9)	C6B—C1B—C2B—C3B	−84.4 (4)
C2A—C3A—C4A—C5A	178.4 (6)	N1B—C1B—C2B—C5B	−81.7 (4)
C3A—C4A—C5A—C6A	−1.4 (11)	C6B—C1B—C2B—C5B	41.7 (4)
C4A—C5A—C6A—C7A	3.0 (11)	C5B—C2B—C3B—C4B	63.4 (6)
C5A—C6A—C7A—C8A	−1.9 (13)	C1B—C2B—C3B—C4B	−170.4 (5)
C4A—C3A—C8A—C7A	2.3 (10)	N1B—C1B—C6B—O1B	25.6 (5)
C2A—C3A—C8A—C7A	−177.2 (7)	C2B—C1B—C6B—O1B	−98.7 (4)
C6A—C7A—C8A—C3A	−0.9 (13)	N1B—C1B—C6B—O2B	−155.5 (4)
N1A—C1A—C9A—O2A	142.1 (4)	C2B—C1B—C6B—O2B	80.2 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O2B	0.91 (3)	2.01 (3)	2.896 (5)	163 (4)
N1A—H2A···O1A^i	0.91 (3)	1.83 (3)	2.740 (5)	177 (5)
N1A—H3A···O2A^ii	0.94 (3)	2.01 (3)	2.949 (5)	177 (4)
N1B—H1B···O2A	0.94 (3)	2.04 (3)	2.933 (5)	157 (4)
N1B—H2B···O2B^iii	0.93 (3)	1.98 (3)	2.895 (5)	169 (4)
N1B—H3B···O1B^iv	0.92 (3)	1.84 (3)	2.758 (5)	174 (5)

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

(VI) L-Phenylalanine–D-alloisoleucine (1/1)

Crystal data

C9H11NO2·C6H13NO2	F(000) = 320
Mr = 296.36	Dx = 1.274 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 5224 reflections
a = 5.2436 (5) Å	θ = 2.8–26.7°
b = 28.949 (3) Å	µ = 0.09 mm^−1
c = 5.4069 (5) Å	T = 296 K
β = 109.747 (1)°	Plate, colourless
V = 772.49 (13) Å^3	0.58 × 0.16 × 0.1 mm
Z = 2

Data collection

Bruker APEXII CCD diffractometer	1668 independent reflections
Radiation source: fine-focus sealed tube	1605 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.017
Detector resolution: 8.3 pixels mm^-1	θmax = 26.7°, θmin = 2.8°
Sets of exposures each taken over 0.5° ω rotation scans	h = −6→6
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	k = −36→36
Tmin = 0.903, Tmax = 0.991	l = −6→6
8740 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.088	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0479P)^2 + 0.1517P] where P = (Fo^2 + 2Fc^2)/3
1668 reflections	(Δ/σ)max < 0.001
210 parameters	Δρmax = 0.16 e Å^−3
7 restraints	Δρmin = −0.16 e Å^−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.

Refinement. Data were collected by measuring four sets of exposures with the detector set at 2θ = 29°, crystal-to-detector distance 6.00 cm. Refinement of F² against ALL reflections.

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

	x	y	z	Uiso*/Ueq
O1A	0.9385 (3)	0.65069 (7)	0.8930 (3)	0.0390 (4)
O2A	0.4907 (3)	0.64146 (6)	0.7469 (3)	0.0346 (4)
N1A	0.9341 (4)	0.66153 (7)	0.3916 (3)	0.0279 (4)
H1A	0.905 (6)	0.6919 (9)	0.421 (5)	0.042*
H2A	0.934 (6)	0.6593 (11)	0.225 (5)	0.042*
H3A	1.107 (5)	0.6560 (11)	0.496 (5)	0.042*
C1A	0.7295 (4)	0.63103 (7)	0.4456 (4)	0.0271 (4)
H11A	0.5513	0.6364	0.3125	0.033*
C2A	0.8191 (5)	0.58148 (8)	0.4237 (5)	0.0405 (6)
H21A	0.8277	0.5771	0.2489	0.049*
H22A	1.0011	0.5775	0.5477	0.049*
C3A	0.6425 (6)	0.54422 (8)	0.4730 (5)	0.0412 (6)
C4A	0.4052 (8)	0.53073 (14)	0.2926 (9)	0.0765 (11)
H41A	0.3421	0.5455	0.1304	0.092*
C5A	0.2547 (8)	0.49501 (16)	0.3472 (11)	0.0918 (14)
H51A	0.0895	0.4870	0.2224	0.110*
C6A	0.3409 (9)	0.47226 (13)	0.5724 (10)	0.0787 (12)
H61A	0.2446	0.4471	0.6017	0.094*
C7A	0.5692 (12)	0.48621 (18)	0.7568 (10)	0.1055 (18)
H71A	0.6269	0.4718	0.9201	0.127*
C8A	0.7201 (11)	0.52176 (16)	0.7079 (8)	0.0890 (14)
H81A	0.8793	0.5306	0.8388	0.107*
C9A	0.7166 (4)	0.64203 (7)	0.7192 (4)	0.0259 (4)
O1B	0.3408 (3)	0.73557 (6)	0.4192 (3)	0.0342 (4)
O2B	0.7839 (3)	0.74939 (6)	0.5546 (3)	0.0334 (4)
N1B	0.3259 (4)	0.73038 (7)	0.9067 (3)	0.0269 (4)
H1B	0.328 (6)	0.7331 (11)	1.075 (5)	0.040*
H2B	0.342 (6)	0.7006 (8)	0.879 (6)	0.040*
H3B	0.170 (5)	0.7409 (10)	0.798 (5)	0.040*
C1B	0.5597 (4)	0.75489 (7)	0.8694 (4)	0.0251 (4)
H11B	0.7262	0.7418	0.9936	0.030*
C2B	0.5533 (5)	0.80673 (8)	0.9319 (4)	0.0344 (5)
H21B	0.4817	0.8096	1.0768	0.041*
C3B	0.3685 (7)	0.83414 (9)	0.7024 (6)	0.0505 (7)
H31B	0.1936	0.8189	0.6378	0.061*
H32B	0.4442	0.8340	0.5617	0.061*
C4B	0.3273 (10)	0.88379 (12)	0.7704 (11)	0.0881 (13)
H41B	0.1837	0.8974	0.6284	0.132*
H42B	0.4915	0.9009	0.7983	0.132*
H43B	0.2807	0.8845	0.9274	0.132*
C5B	0.8413 (7)	0.82552 (13)	1.0286 (8)	0.0667 (9)
H51B	0.9535	0.8060	1.1661	0.100*
H52B	0.8411	0.8563	1.0949	0.100*
H53B	0.9110	0.8261	0.8857	0.100*
C6B	0.5614 (4)	0.74567 (7)	0.5903 (4)	0.0242 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0334 (8)	0.0643 (12)	0.0210 (7)	−0.0068 (8)	0.0113 (6)	−0.0047 (7)
O2A	0.0312 (7)	0.0442 (9)	0.0348 (8)	0.0015 (7)	0.0193 (7)	−0.0005 (7)
N1A	0.0301 (9)	0.0371 (10)	0.0185 (8)	−0.0041 (8)	0.0107 (7)	−0.0032 (7)
C1A	0.0257 (9)	0.0344 (10)	0.0229 (9)	−0.0025 (8)	0.0104 (8)	−0.0026 (8)
C2A	0.0512 (14)	0.0360 (12)	0.0450 (13)	−0.0035 (11)	0.0303 (11)	−0.0083 (11)
C3A	0.0505 (14)	0.0308 (11)	0.0517 (15)	−0.0017 (10)	0.0296 (12)	−0.0082 (10)
C4A	0.063 (2)	0.063 (2)	0.089 (3)	−0.0087 (17)	0.0055 (19)	0.0200 (19)
C5A	0.053 (2)	0.075 (3)	0.130 (4)	−0.0192 (19)	0.009 (2)	0.011 (3)
C6A	0.081 (3)	0.0498 (18)	0.121 (4)	−0.0141 (18)	0.055 (3)	0.007 (2)
C7A	0.135 (4)	0.090 (3)	0.088 (3)	−0.047 (3)	0.033 (3)	0.022 (3)
C8A	0.114 (3)	0.084 (3)	0.058 (2)	−0.047 (3)	0.015 (2)	0.0106 (19)
C9A	0.0312 (10)	0.0273 (10)	0.0228 (10)	0.0010 (8)	0.0139 (8)	0.0012 (8)
O1B	0.0330 (8)	0.0512 (10)	0.0200 (7)	−0.0069 (7)	0.0113 (6)	−0.0050 (7)
O2B	0.0292 (7)	0.0462 (9)	0.0295 (7)	0.0022 (7)	0.0159 (6)	−0.0004 (7)
N1B	0.0304 (9)	0.0336 (9)	0.0191 (8)	−0.0025 (8)	0.0115 (7)	−0.0013 (7)
C1B	0.0222 (9)	0.0346 (10)	0.0191 (8)	0.0004 (8)	0.0078 (7)	−0.0009 (8)
C2B	0.0392 (12)	0.0376 (12)	0.0309 (11)	−0.0080 (10)	0.0178 (9)	−0.0108 (9)
C3B	0.0592 (17)	0.0371 (13)	0.0561 (16)	0.0057 (12)	0.0206 (13)	0.0029 (12)
C4B	0.104 (3)	0.0377 (17)	0.135 (4)	0.0096 (18)	0.057 (3)	0.002 (2)
C5B	0.0501 (16)	0.0620 (19)	0.083 (2)	−0.0231 (14)	0.0165 (16)	−0.0276 (17)
C6B	0.0273 (9)	0.0271 (10)	0.0203 (9)	0.0034 (8)	0.0108 (7)	0.0019 (7)

Geometric parameters (Å, º)

O1A—C9A	1.249 (3)	C8A—H81A	0.9300
O2A—C9A	1.243 (2)	O1B—C6B	1.248 (2)
N1A—C1A	1.493 (3)	O2B—C6B	1.250 (2)
N1A—H1A	0.91 (2)	N1B—C1B	1.488 (3)
N1A—H2A	0.90 (2)	N1B—H1B	0.91 (2)
N1A—H3A	0.90 (2)	N1B—H2B	0.88 (2)
C1A—C2A	1.526 (3)	N1B—H3B	0.88 (2)
C1A—C9A	1.537 (3)	C1B—C6B	1.536 (3)
C1A—H11A	0.9800	C1B—C2B	1.541 (3)
C2A—C3A	1.503 (3)	C1B—H11B	0.9800
C2A—H21A	0.9700	C2B—C3B	1.515 (4)
C2A—H22A	0.9700	C2B—C5B	1.522 (4)
C3A—C4A	1.353 (5)	C2B—H21B	0.9800
C3A—C8A	1.361 (5)	C3B—C4B	1.517 (5)
C4A—C5A	1.392 (6)	C3B—H31B	0.9700
C4A—H41A	0.9300	C3B—H32B	0.9700
C5A—C6A	1.322 (7)	C4B—H41B	0.9600
C5A—H51A	0.9300	C4B—H42B	0.9600
C6A—C7A	1.336 (7)	C4B—H43B	0.9600
C6A—H61A	0.9300	C5B—H51B	0.9600
C7A—C8A	1.377 (6)	C5B—H52B	0.9600
C7A—H71A	0.9300	C5B—H53B	0.9600
C1A—N1A—H1A	111.3 (19)	C1B—N1B—H1B	111.3 (18)
C1A—N1A—H2A	113.2 (19)	C1B—N1B—H2B	108 (2)
H1A—N1A—H2A	107 (3)	H1B—N1B—H2B	107 (3)
C1A—N1A—H3A	113.9 (19)	C1B—N1B—H3B	111.5 (19)
H1A—N1A—H3A	105 (3)	H1B—N1B—H3B	109 (3)
H2A—N1A—H3A	106 (3)	H2B—N1B—H3B	110 (3)
N1A—C1A—C2A	106.29 (18)	N1B—C1B—C6B	109.21 (16)
N1A—C1A—C9A	109.50 (17)	N1B—C1B—C2B	110.78 (17)
C2A—C1A—C9A	112.59 (18)	C6B—C1B—C2B	113.10 (17)
N1A—C1A—H11A	109.5	N1B—C1B—H11B	107.9
C2A—C1A—H11A	109.5	C6B—C1B—H11B	107.9
C9A—C1A—H11A	109.5	C2B—C1B—H11B	107.9
C3A—C2A—C1A	115.90 (19)	C3B—C2B—C5B	112.3 (3)
C3A—C2A—H21A	108.3	C3B—C2B—C1B	112.68 (19)
C1A—C2A—H21A	108.3	C5B—C2B—C1B	109.3 (2)
C3A—C2A—H22A	108.3	C3B—C2B—H21B	107.4
C1A—C2A—H22A	108.3	C5B—C2B—H21B	107.4
H21A—C2A—H22A	107.4	C1B—C2B—H21B	107.4
C4A—C3A—C8A	116.5 (3)	C2B—C3B—C4B	113.7 (3)
C4A—C3A—C2A	123.4 (3)	C2B—C3B—H31B	108.8
C8A—C3A—C2A	120.0 (3)	C4B—C3B—H31B	108.8
C3A—C4A—C5A	120.7 (4)	C2B—C3B—H32B	108.8
C3A—C4A—H41A	119.6	C4B—C3B—H32B	108.8
C5A—C4A—H41A	119.6	H31B—C3B—H32B	107.7
C6A—C5A—C4A	121.6 (4)	C3B—C4B—H41B	109.5
C6A—C5A—H51A	119.2	C3B—C4B—H42B	109.5
C4A—C5A—H51A	119.2	H41B—C4B—H42B	109.5
C5A—C6A—C7A	118.6 (4)	C3B—C4B—H43B	109.5
C5A—C6A—H61A	120.7	H41B—C4B—H43B	109.5
C7A—C6A—H61A	120.7	H42B—C4B—H43B	109.5
C6A—C7A—C8A	120.7 (4)	C2B—C5B—H51B	109.5
C6A—C7A—H71A	119.6	C2B—C5B—H52B	109.5
C8A—C7A—H71A	119.6	H51B—C5B—H52B	109.5
C3A—C8A—C7A	121.8 (4)	C2B—C5B—H53B	109.5
C3A—C8A—H81A	119.1	H51B—C5B—H53B	109.5
C7A—C8A—H81A	119.1	H52B—C5B—H53B	109.5
O2A—C9A—O1A	126.50 (19)	O1B—C6B—O2B	125.84 (17)
O2A—C9A—C1A	117.82 (18)	O1B—C6B—C1B	117.25 (17)
O1A—C9A—C1A	115.67 (17)	O2B—C6B—C1B	116.91 (17)
N1A—C1A—C2A—C3A	179.6 (2)	C2A—C1A—C9A—O2A	−100.4 (2)
C9A—C1A—C2A—C3A	59.7 (3)	N1A—C1A—C9A—O1A	−38.6 (3)
C1A—C2A—C3A—C4A	78.8 (4)	C2A—C1A—C9A—O1A	79.4 (2)
C1A—C2A—C3A—C8A	−101.9 (4)	N1B—C1B—C2B—C3B	−83.0 (2)
C8A—C3A—C4A—C5A	−1.2 (6)	C6B—C1B—C2B—C3B	39.9 (3)
C2A—C3A—C4A—C5A	178.0 (4)	N1B—C1B—C2B—C5B	151.3 (2)
C3A—C4A—C5A—C6A	−2.0 (8)	C6B—C1B—C2B—C5B	−85.7 (3)
C4A—C5A—C6A—C7A	4.5 (8)	C5B—C2B—C3B—C4B	−64.2 (4)
C5A—C6A—C7A—C8A	−3.8 (9)	C1B—C2B—C3B—C4B	171.8 (3)
C4A—C3A—C8A—C7A	1.9 (7)	N1B—C1B—C6B—O1B	24.8 (3)
C2A—C3A—C8A—C7A	−177.4 (5)	C2B—C1B—C6B—O1B	−99.0 (2)
C6A—C7A—C8A—C3A	0.6 (9)	N1B—C1B—C6B—O2B	−155.76 (18)
N1A—C1A—C9A—O2A	141.5 (2)	C2B—C1B—C6B—O2B	80.4 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O2B	0.91 (2)	2.00 (2)	2.887 (3)	162 (3)
N1A—H2A···O1A^i	0.90 (2)	1.82 (2)	2.722 (2)	176 (3)
N1A—H3A···O2A^ii	0.90 (2)	2.06 (2)	2.959 (3)	177 (3)
N1B—H1B···O1B^iii	0.91 (2)	1.84 (2)	2.750 (2)	177 (3)
N1B—H2B···O2A	0.88 (2)	2.10 (2)	2.937 (3)	157 (3)
N1B—H3B···O2B^iv	0.88 (2)	2.02 (2)	2.890 (2)	166 (3)

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