(S)-5-Benzyl­imidazolidine-2,4-dione monohydrate

The crystal structure of the title compound, C₁₀H₁₀N₂O₂·H₂O, also known as L-5-benzylhydantoin monohydrate, is described in terms of two-dimensional supra­molecular arrays built up from infinite chains assembled via N-H...O and O-H...O hydrogen bonds among the organic mol­ecules and solvent water mol­ecules, with graph-set R³₃(10)C(5)C²₂(6). The hydrogen-bond network is reinforced by stacking of the layers through C-H...[pi] inter­actions.

S1. Comment

Imidazolidine-2,4-dione, or hydantoin, is a five-membered heterocycle ring containing a reactive cyclic urea nucleus. This heterocycle represents a significant molecular template in combinatorial chemistry libraries (Boeijen et al. 1998; Park et al., 2001), principally because of the four possible substitution points. Solid-phase syntheses including hydantoin as a starting building block have been reported recently (Ganesan, 2003; Vázquez et al., 2004; Alsina et al., 2005). Hydantoin derivatives have attracted great interest in drug innovation because of their wide range of therapeutic properties (Mutschler & Derendorf, 1995). In particular, the five-subtituted hydantoins have been found to be valuable precursors of a great variety of heterocyclic systems that are associated with a wide range of biological activities, including antiarrhythmic (Knabe et al., 1997), anticonvulsant (Singh et al., 2005) and antitumoral agents (Carmi et al., 2006). The best known hydantoin is 5,5-diphenylhydantoin, or phenytoin, which is the most widely use anti-epileptic drug since the experimental determination of its anticonvulsant properties (Putnam & Merrit, 1937). In addition, they are known for their uses as herbicides (Shiozaki, 2002) and fungicides (Marton et al., 1993). On the other hand, the biocatalytic conversion of 5-subtituted hydantoins and the related N-carbamoyl compounds to amino acids has recently received considerable attention for their potential applications in the industrial production of optically pure amino acids, through an enantioselective enzymatic reaction (Wilms et al., 2001; Chen et al., 2003; Burton & Dorrington, 2004).

Continuing with our studies on N-carbamoyl amino acids and hydantoin compounds (Seijas et al., 2006, 2007), in this work we report the crystal structure of the title compound (I), a new 5-subtituted hydantoin derivative.

The asymmetric unit of (I) consist of one (L)-5-benzyl hydantoin molecule and a crystallization water molecule. The dihedral angle between the hydantoin and benzene rings is 55.6 (3)°. The organic molecule adopts a gauche conformation (Fig. 1). The hydantoin ring is essentially planar, with maximum deviations of 0.024 (4) Å for C4 and -0.023 (4) Å for C5. The N1—C2—O2 bond angle [129.2 (3)°] is greater than the N3—C2—O2 angle [123.3 (3)°]. This difference is also observed in the hydantoin molecule (Yu et al., 2004) and 50 other hydantoin derivative compounds reported in the Cambridge Structural Database (Version 5.28; Allen, 2002) with both NH groups unsubstituted and sp³ hybridization at C5.

The structure of (I) is built up from the self-assembly of the hydantoin molecules with solvent water molecules via hydrogen-bonding interactions. The water molecule is involved as a donor and an acceptor of hydrogen bonds. Molecules of (I) form four conventional hydrogen bonds. The N3—H3···O1W(x + 1, y, z) and O1W—H1W···O4(x - 1, y - 1, z) form infinite chains, which run along the b axis. These chains may be described in graph-set notation as C²₂(6) (Bernstein et al., 1995) (Fig. 2). Adjacent chains are linked laterally by O1W—H2W···O2(x, y, z) and N1—H1···O4(x - 1, y - 1, z) [should this be the same as ii in table?] hydrogen bonds, to form infinite chains parallel to the a axis with graph set motifs C²₂(6) and C(5), respectively (Fig. 2). Together, these hydrogen-bond patterns produce a two-dimensional array parallel to the ab plane with graph set R³₃(10) and the formation of a 15 atom macrocycle (Fig. 2). This graph set is also observed in the hydantoin compounds ROKSOZ (Gauthier et al. 1997) and SINZEU (Galdecki & Karolak-Wojciechowska, 1986). Details of the hydrogen-bonding geometry are given in Table 2. Layers join pairwise by C—H···π interactions (Fig. 3). The C10/H10 group of the benzene ring is oriented towards the face of the aromatic ring of a neighboring molecule [C10—H10···Cg(x + 1, y - 1/2, 1 - z) = 3.13 (3) Å]; where Cg is the centroid of the C7–C12 ring. This interaction generates a herringbone-like array in the bc plane (Fig. 3).

Related literature

For related literature, see: Allen (2002); Alsina et al. (2005); Bernstein et al. (1995); Boeijen et al. (1998); Burton & Dorrington (2004); Carmi et al. (2006); Chen et al. (2003); Galdecki & Karolak-Wojciechowska (1986); Ganesan (2003); Gauthier et al. (1997); Knabe et al. (1997); Marton et al. (1993); Mutschler & Derendorf (1995); Park et al. (2001); Putnam & Merrit (1937); Seijas et al. (2006, 2007); Shiozaki (2002); Singh et al. (2005); Vázquez et al. (2004); Wilms et al. (2001); Yu et al. (2004).

S2. Experimental

L-Phenylalanine (500 mg, 3.0 mmol) was dissolved in 20 ml of water and the solution was acidified with concentrated HCl (37% v/v) to pH 5.5. KOCN (1458 mg, 18.0 mmol) was then added to this solution. The mixture was warmed, with agitation, to 333 K over a period of 4 h. The resulting solution was cooled at room temperature and acidified with concentrated HCl (37% v/v) to pH 1, at which point a white solid precipitated. The solid was filtered off and washed with cool water (m.p. 467–469 K). Crystals of (I) suitable for X-ray diffraction analysis were obtained by slow evaporation of a 1:1 water–ethanol solution.

S3. Refinement

All H atoms attached to C atoms were positioned geometrically and assigned U_iso(H) values equal to 1.2 times U_eq(C). The H atoms of the water molecule were located in the final difference Fourier map and their U_iso(H) values were set to 1.5U_eq(O). The absolute structure was assigned from the known configuration of L-phenylalanine. Please check changes to text.

Computing details

Data collection: MSC/AFC Difractometer Control Software (Molecular Structure Corporation, 1993); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN (Molecular Structure Corporation, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: PLATON (Spek, 2003) and publCIF (Westrip, 2007).

Figures

	Fig. 1. Figure 1. A view of (I), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 20% probability level and H atoms are shown as spheres of arbitrary radii.
	Fig. 2. Figure 2. A partial packing view of (I). Hydrogen bonds are shown as green lines. H atoms not involved in hydrogen bonding have been omitted for clarity. [Symmetry codes: (i) x + 1, y, z; (ii) x - 1, y, z; (iii) x - 1, y - 1, z.]
	Fig. 3. Figure 3. A packing view of (I) in the bc plane, showing the herringbone-like array. [Symmetry code: (v) -x + 1, y - 1/2, -z + 1.]

(S)-5-Benzylimidazolidine-2,4-dione monohydrate

Crystal data

C10H10N2O2·H2O	F(000) = 220
Mr = 208.22	Dx = 1.244 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: P 2yb	Cell parameters from 25 reflections
a = 6.229 (2) Å	θ = 28.2–36.7°
b = 6.244 (3) Å	µ = 0.09 mm^−1
c = 14.475 (3) Å	T = 293 K
β = 99.05 (3)°	Laminar, colourless
V = 556.0 (3) Å^3	0.40 × 0.36 × 0.20 mm
Z = 2

Data collection

Rigaku AFC-7S diffractometer	Rint = 0.006
Radiation source: normal-focus sealed tube	θmax = 25.0°, θmin = 2.9°
Graphite monochromator	h = 0→7
ω–2θ scans	k = 0→7
1192 measured reflections	l = −17→17
1088 independent reflections	3 standard reflections every 150 reflections
976 reflections with I > 2σ(I)	intensity decay: none

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.141	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0901P)^2 + 0.1492P] where P = (Fo^2 + 2Fc^2)/3
1088 reflections	(Δ/σ)max = 0.003
138 parameters	Δρmax = 0.56 e Å^−3
1 restraint	Δρmin = −0.27 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. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq
N1	0.3885 (4)	1.1282 (5)	0.1167 (2)	0.0448 (8)
H1	0.2502	1.1467	0.1105	0.054*
C2	0.4809 (5)	0.9464 (6)	0.0966 (2)	0.0404 (8)
O2	0.3953 (4)	0.7774 (5)	0.06779 (19)	0.0538 (7)
N3	0.7053 (4)	0.9776 (5)	0.1134 (2)	0.0414 (7)
H3	0.7993	0.8802	0.1067	0.050*
C4	0.7559 (5)	1.1784 (6)	0.1412 (2)	0.0428 (8)
O4	0.9417 (4)	1.2550 (5)	0.15754 (19)	0.0559 (7)
C5	0.5459 (5)	1.2921 (6)	0.1501 (3)	0.0457 (8)
H5	0.5267	1.4162	0.1082	0.055*
C6	0.5379 (7)	1.3635 (7)	0.2513 (3)	0.0607 (10)
H6A	0.6487	1.4715	0.2691	0.073*
H6B	0.3977	1.4284	0.2542	0.073*
C7	0.5730 (7)	1.1823 (8)	0.3196 (3)	0.0606 (10)
C11	0.812 (1)	0.9725 (17)	0.4309 (4)	0.113 (2)
H11	0.9500	0.9474	0.4642	0.136*
C8	0.4061 (9)	1.0438 (10)	0.3314 (3)	0.0791 (15)
H8	0.2675	1.0678	0.2986	0.095*
C9	0.442 (1)	0.8701 (13)	0.3911 (4)	0.101 (2)
H9	0.3295	0.7760	0.3973	0.121*
C10	0.646 (2)	0.8380 (14)	0.4412 (4)	0.121 (3)
H10	0.6699	0.7234	0.4825	0.145*
C12	0.7775 (9)	1.1473 (13)	0.3708 (3)	0.0853 (16)
H12	0.8911	1.2404	0.3649	0.102*
O1W	−0.0237 (5)	0.6599 (6)	0.0681 (3)	0.0877 (12)
H1W	−0.0242	0.5249	0.1036	0.132*
H2W	0.1128	0.6900	0.0688	0.132*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0285 (12)	0.0458 (19)	0.0591 (16)	0.0041 (13)	0.0034 (11)	−0.0047 (14)
C2	0.0308 (15)	0.0403 (19)	0.0510 (18)	−0.0002 (15)	0.0089 (13)	0.0034 (14)
O2	0.0406 (12)	0.0442 (14)	0.0771 (17)	−0.0078 (12)	0.0106 (11)	−0.0098 (13)
N3	0.0274 (12)	0.0367 (15)	0.0610 (16)	0.0024 (12)	0.0094 (11)	0.0023 (13)
C4	0.0337 (15)	0.0431 (18)	0.0517 (17)	−0.0005 (15)	0.0071 (12)	0.0052 (16)
O4	0.0391 (12)	0.0527 (16)	0.0747 (16)	−0.0087 (13)	0.0047 (11)	−0.0008 (13)
C5	0.0402 (16)	0.0371 (17)	0.0596 (19)	0.0021 (16)	0.0074 (14)	0.0010 (16)
C6	0.059 (2)	0.053 (2)	0.071 (2)	0.0029 (19)	0.0121 (18)	−0.019 (2)
C7	0.066 (2)	0.068 (3)	0.0496 (18)	0.004 (2)	0.0139 (17)	−0.014 (2)
C11	0.124 (5)	0.144 (7)	0.069 (3)	0.033 (6)	0.013 (3)	0.024 (4)
C8	0.087 (3)	0.091 (4)	0.064 (3)	−0.001 (3)	0.029 (2)	−0.006 (3)
C9	0.133 (6)	0.099 (5)	0.080 (3)	−0.004 (4)	0.047 (4)	0.007 (4)
C10	0.189 (8)	0.106 (6)	0.075 (4)	0.025 (6)	0.045 (4)	0.029 (4)
C12	0.083 (3)	0.111 (5)	0.059 (2)	0.003 (4)	0.004 (2)	−0.003 (3)
O1W	0.0459 (15)	0.0506 (18)	0.172 (3)	0.0047 (15)	0.0342 (18)	0.009 (2)

Geometric parameters (Å, º)

N1—C2	1.325 (5)	C7—C8	1.383 (7)
N1—C5	1.447 (5)	C7—C12	1.386 (7)
N1—H1	0.8600	C11—C10	1.361 (12)
C2—O2	1.226 (5)	C11—C12	1.391 (11)
C2—N3	1.394 (4)	C11—H11	0.9300
N3—C4	1.339 (5)	C8—C9	1.383 (9)
N3—H3	0.8600	C8—H8	0.9300
C4—O4	1.240 (4)	C9—C10	1.372 (10)
C4—C5	1.512 (5)	C9—H9	0.9300
C5—C6	1.539 (5)	C10—H10	0.9300
C5—H5	0.9800	C12—H12	0.9300
C6—C7	1.496 (7)	O1W—H1W	0.99
C6—H6A	0.9700	O1W—H2W	0.87
C6—H6B	0.9700
C2—N1—C5	112.6 (3)	C5—C6—H6B	109.0
C2—N1—H1	123.7	H6A—C6—H6B	107.8
C5—N1—H1	123.7	C8—C7—C12	118.7 (5)
O2—C2—N1	129.2 (3)	C8—C7—C6	121.3 (4)
O2—C2—N3	123.3 (3)	C12—C7—C6	119.9 (5)
N1—C2—N3	107.5 (3)	C10—C11—C12	120.4 (6)
C4—N3—C2	111.4 (3)	C10—C11—H11	119.8
C4—N3—H3	124.3	C12—C11—H11	119.8
C2—N3—H3	124.3	C9—C8—C7	121.1 (6)
O4—C4—N3	125.9 (3)	C9—C8—H8	119.5
O4—C4—C5	126.6 (4)	C7—C8—H8	119.5
N3—C4—C5	107.4 (3)	C10—C9—C8	119.3 (7)
N1—C5—C4	100.9 (3)	C10—C9—H9	120.3
N1—C5—C6	113.7 (3)	C8—C9—H9	120.3
C4—C5—C6	112.0 (3)	C11—C10—C9	120.6 (7)
N1—C5—H5	110.0	C11—C10—H10	119.7
C4—C5—H5	110.0	C9—C10—H10	119.7
C6—C5—H5	110.0	C7—C12—C11	119.8 (7)
C7—C6—C5	112.7 (3)	C7—C12—H12	120.1
C7—C6—H6A	109.0	C11—C12—H12	120.1
C5—C6—H6A	109.0	H1W—O1W—H2W	105
C7—C6—H6B	109.0

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···O1W^i	0.86	1.90	2.750 (4)	169
O1W—H2W···O2	0.87	1.85	2.712 (4)	175
N1—H1···O4^ii	0.86	2.24	3.040 (4)	154
O1W—H1W···O4^iii	0.99	1.88	2.864 (5)	172
C5—H5···O2^iv	0.98	2.44	3.336 (5)	152

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