[3R-(3β,4β,5β)]-3-(Acetyl­amino)-3,4-di­hydro-4-hydroxy-5-(hydroxy­methyl)­furan-2(5H)-one monohydrate

The title compound, C₇H₁₁NO₅·H₂O, a hydrated stereoisomer of the N-acetyl­ated lactone of polyoxamic acid, contains a lactone ring with an envelope conformation, all substituents being cis. Intermolecular hydrogen bonds involving all possible donors link the lactone mol­ecules into sheets, which are interlinked by the water mol­ecules to give a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 160 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.038
• wR factor = 0.082
• Data-to-parameter ratio = 9.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           28.36
         From the CIF: _reflns_number_total               1352
         TEST2: Reflns within _diffrn_reflns_theta_max
         Count of symmetry unique reflns         1425
         Completeness (_total/calc)             94.88%
          Alert C: < 95% complete

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           28.36
         From the CIF: _reflns_number_total               1352
         Count of symmetry unique reflns         1425
         Completeness (_total/calc)             94.88%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured         0
         Fraction of Friedel pairs measured     0.000
         Are heavy atom types Z>Si present           no
          Please check that the estimate of the number of Friedel pairs is
          correct. If it is not, please give the correct count in the
          _publ_section_exptl_refinement section of the submitted CIF.


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

S1. Comment

The title lactone, (I), was prepared as part of a project concerned with the synthesis of β-hydroxy-α-amino acids via (arylthio)nitrooxiranes (Jackson et al., 1995). Its crystal structure has been determined in order to confirm the relative stereochemistry of the substituents on the lactone ring, postulated as all-cis. The compound (Fig. 1) is a hydrated stereoisomer of the N-acetylated lactone of polyoxamic acid, the crystal structure of which has already been reported (Saskena et al., 1986).

A search of the Cambridge Structural Database (Allen, 2002) finds 30 crystallographically characterized γ-lactones with a nitrogen substituent on the C atom adjacent to the carbonyl group, two of which are closely related to (I). One of these is the isomeric N-acetylated lactone of polyoxamic acid mentioned above, and the other has an azido substituent instead of the acetylamino group (Baird et al., 1987). Both of these have a mixture of cis and trans substituents on the ring, with the nitrogen substituent trans to the hydroxymethyl group, and the hydroxy group cis to one of these and trans to the other.

The lactone ring in (I) has an envelope conformation, with atom C2 as the flap angle; C2 lies 0.558 (4) Å out of the mean plane of the other four atoms (r.m.s. deviation 0.021 Å), and this mean plane makes a dihedral angle of 35.0 (2)° with the plane formed by atoms C1, C2 and C3. The acetylamino and hydroxymethyl substituents are equatorial, which the hydroxy substituent on C2 is axial.

Details of the hydrogen bonds are given in Table 2. The N—H and both O—H groups serve as donors, together with both O—H groups of the water molecule, and the acceptors are the two carbonyl O atoms (O5 accepts two hydrogen bonds), the OH atom O4 and the water O atom. All hydrogen bonds are intermolecular. Four hydrogen bonds per lactone molecule (O2 and N1 as donors, and O3 and O5 as acceptors link these into sheets, as shown in Fig. 2. Interactions with the water molecules crosslink the sheets into the full three-dimensional network, as shown in Fig. 3.

S2. Experimental

The compound was prepared as described by Jackson et al. (1995), and was recrystallized from ethanol, which is presumably the source of the water of crystallization.

S3. Refinement

Carbon-bound H atoms were placed geometrically and refined with a riding model (including free rotation about C—C bonds), and with U_iso constrained to be 1.2 (1.5 for methyl groups) times U_eq of the carrier atom. H atoms bonded to N and O were located in a difference map and were refined freely with individual isotropic displacement parameters. In the absence of significant anomalous scattering effects, Friedel pairs were merged. The absolute configuration was assumed from the known configuration of the starting material, viz. 2,3-isopropylidene-L-threitol.

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: local programs; data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Figures

	Fig. 1. The structure of the asymmetric unit of (I), with atom labels and 50% probability ellipsoids for non-H atoms.
	Fig. 2. Sheets of lactone molecules formed by intermolecular hydrogen bonds, viewed along the c axis.
	Fig. 3. The crystal packing, viewed along the a axis, showing the linking of molecular sheets through hydrogen bonds with water molecules.

(I)

Crystal data

C7H11NO5·H2O	Dx = 1.437 Mg m^−3
Mr = 207.18	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 3459 reflections
a = 4.5292 (5) Å	θ = 1.9–28.2°
b = 9.7807 (10) Å	µ = 0.13 mm^−1
c = 21.622 (2) Å	T = 160 K
V = 957.83 (18) Å^3	Needle, colourless
Z = 4	0.30 × 0.08 × 0.04 mm
F(000) = 440

Data collection

Bruker SMART 1K CCD diffractometer	1101 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.047
Graphite monochromator	θmax = 28.4°, θmin = 1.9°
Detector resolution: 8.192 pixels mm^-1	h = −5→5
ω rotation with narrow frames scans	k = −9→12
5877 measured reflections	l = −26→27
1352 independent 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)] = 0.038	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.082	w = 1/[σ^2(Fo^2) + (0.0426P)^2 + 0.0129P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
1352 reflections	Δρmax = 0.25 e Å^−3
149 parameters	Δρmin = −0.19 e Å^−3
0 restraints	Extinction correction: SHELXTL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.016 (3)

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

	x	y	z	Uiso*/Ueq
O1	0.6310 (4)	0.53995 (15)	0.35100 (7)	0.0191 (4)
C1	0.4114 (5)	0.6463 (2)	0.36592 (10)	0.0170 (5)
H1A	0.2089	0.6057	0.3645	0.020*
C2	0.4439 (6)	0.7518 (2)	0.31384 (10)	0.0178 (5)
H2A	0.2564	0.8030	0.3061	0.021*
O2	0.6866 (4)	0.84040 (17)	0.32424 (8)	0.0229 (4)
H2	0.624 (7)	0.916 (3)	0.3363 (13)	0.039 (9)*
C3	0.5289 (5)	0.6597 (2)	0.25947 (10)	0.0159 (5)
H3	0.3465	0.6170	0.2420	0.019*
C4	0.7129 (5)	0.5501 (2)	0.29129 (11)	0.0170 (5)
O3	0.9063 (4)	0.48047 (16)	0.26967 (8)	0.0226 (4)
C5	0.4712 (6)	0.6994 (2)	0.42973 (11)	0.0226 (6)
H5A	0.6792	0.7300	0.4324	0.027*
H5B	0.3432	0.7795	0.4378	0.027*
O4	0.4180 (5)	0.5978 (2)	0.47545 (8)	0.0281 (4)
H4	0.581 (8)	0.555 (3)	0.4848 (15)	0.049 (10)*
N1	0.6873 (5)	0.7287 (2)	0.21064 (9)	0.0177 (4)
H1	0.797 (7)	0.798 (3)	0.2196 (13)	0.033 (8)*
C6	0.6841 (6)	0.6851 (2)	0.15181 (11)	0.0197 (5)
O5	0.5416 (4)	0.58314 (17)	0.13534 (7)	0.0257 (4)
C7	0.8578 (6)	0.7681 (3)	0.10595 (11)	0.0277 (6)
H7A	0.7231	0.8078	0.0753	0.042*
H7B	1.0011	0.7091	0.0850	0.042*
H7C	0.9624	0.8416	0.1276	0.042*
O6	0.9079 (5)	0.4663 (2)	0.50663 (9)	0.0282 (5)
H6A	1.059 (11)	0.503 (4)	0.4918 (18)	0.076 (14)*
H6B	0.934 (8)	0.454 (3)	0.5467 (16)	0.048 (10)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0218 (9)	0.0187 (8)	0.0168 (8)	0.0045 (7)	0.0028 (7)	0.0031 (7)
C1	0.0154 (11)	0.0184 (11)	0.0171 (11)	0.0020 (10)	0.0016 (10)	0.0004 (9)
C2	0.0190 (12)	0.0179 (11)	0.0164 (11)	0.0014 (10)	0.0029 (10)	0.0018 (9)
O2	0.0257 (9)	0.0161 (9)	0.0269 (9)	−0.0033 (8)	0.0068 (8)	−0.0044 (8)
C3	0.0148 (11)	0.0201 (11)	0.0129 (11)	−0.0012 (9)	−0.0003 (9)	0.0001 (9)
C4	0.0172 (11)	0.0143 (10)	0.0195 (12)	−0.0030 (10)	−0.0006 (10)	−0.0023 (9)
O3	0.0229 (9)	0.0206 (8)	0.0244 (9)	0.0032 (7)	0.0018 (8)	−0.0025 (7)
C5	0.0259 (14)	0.0240 (12)	0.0179 (12)	−0.0032 (11)	0.0025 (11)	−0.0014 (10)
O4	0.0255 (10)	0.0402 (11)	0.0187 (9)	0.0015 (9)	0.0044 (8)	0.0077 (8)
N1	0.0210 (11)	0.0161 (10)	0.0159 (10)	−0.0034 (9)	0.0008 (8)	0.0009 (8)
C6	0.0229 (12)	0.0183 (11)	0.0178 (12)	0.0029 (11)	0.0017 (11)	0.0007 (9)
O5	0.0354 (11)	0.0217 (8)	0.0199 (9)	−0.0103 (8)	−0.0005 (8)	−0.0012 (7)
C7	0.0395 (17)	0.0253 (13)	0.0184 (12)	−0.0087 (12)	0.0059 (12)	−0.0012 (11)
O6	0.0313 (11)	0.0317 (11)	0.0216 (10)	−0.0022 (9)	0.0005 (9)	0.0043 (8)

Geometric parameters (Å, º)

O1—C1	1.475 (3)	C5—H5A	0.990
O1—C4	1.347 (3)	C5—H5B	0.990
C1—H1A	1.000	C5—O4	1.422 (3)
C1—C2	1.534 (3)	O4—H4	0.87 (4)
C1—C5	1.499 (3)	N1—H1	0.87 (3)
C2—H2A	1.000	N1—C6	1.341 (3)
C2—O2	1.418 (3)	C6—O5	1.240 (3)
C2—C3	1.530 (3)	C6—C7	1.504 (3)
O2—H2	0.83 (3)	C7—H7A	0.980
C3—H3	1.000	C7—H7B	0.980
C3—C4	1.523 (3)	C7—H7C	0.980
C3—N1	1.444 (3)	O6—H6A	0.84 (5)
C4—O3	1.204 (3)	O6—H6B	0.88 (3)
C1—O1—C4	110.09 (16)	C3—C4—O3	128.4 (2)
O1—C1—H1A	109.4	C1—C5—H5A	109.3
O1—C1—C2	104.42 (17)	C1—C5—H5B	109.3
O1—C1—C5	108.92 (19)	C1—C5—O4	111.52 (19)
H1A—C1—C2	109.4	H5A—C5—H5B	108.0
H1A—C1—C5	109.4	H5A—C5—O4	109.3
C2—C1—C5	115.15 (19)	H5B—C5—O4	109.3
C1—C2—H2A	112.3	C5—O4—H4	111 (2)
C1—C2—O2	111.66 (19)	C3—N1—H1	119.3 (19)
C1—C2—C3	101.10 (16)	C3—N1—C6	122.7 (2)
H2A—C2—O2	112.3	H1—N1—C6	118.0 (19)
H2A—C2—C3	112.3	N1—C6—O5	122.2 (2)
O2—C2—C3	106.65 (19)	N1—C6—C7	116.6 (2)
C2—O2—H2	109 (2)	O5—C6—C7	121.1 (2)
C2—C3—H3	109.2	C6—C7—H7A	109.5
C2—C3—C4	101.81 (17)	C6—C7—H7B	109.5
C2—C3—N1	114.35 (18)	C6—C7—H7C	109.5
H3—C3—C4	109.2	H7A—C7—H7B	109.5
H3—C3—N1	109.2	H7A—C7—H7C	109.5
C4—C3—N1	112.79 (19)	H7B—C7—H7C	109.5
O1—C4—C3	109.53 (18)	H6A—O6—H6B	109 (4)
O1—C4—O3	122.1 (2)
C4—O1—C1—C2	−18.0 (2)	C1—O1—C4—O3	174.4 (2)
C4—O1—C1—C5	−141.52 (19)	C2—C3—C4—O1	25.7 (2)
O1—C1—C2—O2	−80.5 (2)	C2—C3—C4—O3	−153.6 (2)
O1—C1—C2—C3	32.6 (2)	N1—C3—C4—O1	148.75 (19)
C5—C1—C2—O2	38.9 (3)	N1—C3—C4—O3	−30.6 (3)
C5—C1—C2—C3	152.0 (2)	O1—C1—C5—O4	−66.9 (3)
C1—C2—C3—C4	−34.4 (2)	C2—C1—C5—O4	176.3 (2)
C1—C2—C3—N1	−156.37 (19)	C2—C3—N1—C6	−154.2 (2)
O2—C2—C3—C4	82.4 (2)	C4—C3—N1—C6	90.1 (3)
O2—C2—C3—N1	−39.5 (2)	C3—N1—C6—O5	0.8 (4)
C1—O1—C4—C3	−5.0 (2)	C3—N1—C6—C7	179.5 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O5^i	0.83 (3)	1.90 (3)	2.733 (2)	176 (3)
O4—H4···O6	0.87 (4)	1.78 (4)	2.652 (3)	178 (3)
N1—H1···O3^ii	0.87 (3)	2.24 (3)	3.104 (3)	173 (3)
O6—H6A···O4^iii	0.84 (5)	1.90 (5)	2.729 (3)	168 (4)
O6—H6B···O5^iv	0.88 (3)	1.95 (3)	2.834 (3)	175 (3)

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