supplementary materials


bx2427 scheme

Acta Cryst. (2012). E68, o3421-o3422    [ doi:10.1107/S1600536812047617 ]

(1R,3R,4R,6S)-4-(7-Methoxy-2-oxo-2H-chromen-6-yl)-1-methyl-3,6-dioxabicyclo[3.1.0]hexan-2-yl acetate

W. Phakhodee, S. Laphookhieo, T. J. Prior and A. Rujiwatra

Abstract top

In the title compound, C17H16O7, which was isolated from the leaves of Micromelum integerrimum, the furan ring adopts an envelope conformation with the O atom as the flap. An intramolecular C-H...O hydrogen bond occurs. The carbonyl O atom is disordered in a 0.57 (8):0.43 (8) ratio. In the crystal, molecules are linked by weak C-H...O hydrogen bonds into a C(10) chain along [010].

Comment top

Micromelum integerrimum is a shrub in the Rutacae family containing the coumarin molecule, micromilin, as the major chemical constituent (Cassady et al., 1979). Many coumarins including micromilin have been extracted from Rutacae plants, and for some their cytotoxicity has been investigated (Sripisut et al., 2012; He et al., 2001). In the attempt to investigate the chemical constitutents of the extract of Micromelum integerrimum leaves collected from Chiang Rai province in the Northern part of Thailand (March 2012), the colourless crystals of the title compound have been isolated and examined.

The absolute configurations of the four chiral centres in the molecule, (I) (C11, C12, C13, and C14) were assigned from a previous report (Das et al., 1984) as R, R, R and S, respectively. The benzene and dihydropyran ring system (C2–C10/O1) and also the carboxyl O2 and the methoxy O3 atoms are co-planar with the r.m.s. 0.004 (3) Å (Spek, 2009). A deviation of atoms O2 and O3 from the benzene and dihydropyran ring system are 0.028 (2) Å and 0.040 (2) Å, respectively. The five-membered furan ring (C11–C14/O11) shows envelope conformation with the puckering atom O11 of 0.075 (2) Å, and forms an angle of 66.11 (9)° to the twelve-membered benzene–dihydropyran due to free rotation about the C6—C11 bond. The puckering parameters Q and φ of the furan ring are 0.116 (2) Å and 176.4 (12)°, respectively (Cremer & Pople, 1975). The orientation of the oxiran ring (C12–C13/O12) attached to the furan can be defined by the dihedral angle being 79.5 (2)° with atom O12 of the oxirane ring located 1.250 (2) Å away from the furan plane. Regarding the acetate group, atom O19 shows minor positional disorder over two sites. The acetate O13 is arranged at 64.19 (15)° in reference to the furan plane, and the torsion angle measured on C14–O13–C17–C18 is 171.6 (2)°.In the crystal of (I), the molecules are linked by weak C—H···O hydrogen-bonding interactions into a chain along [010] with set-graph notation C(10), (Bernstein, et al., 1995)

Related literature top

Micromelum integerrimum is a shrub in the Rutacae family containing the coumarin molecule, micromelin, as the major chemical constituent (Cassady et al., 1979). Many coumarins including micromelin have been extracted from Rutacae plants, and for some their cytotoxicity has been investigated (Sripisut et al., 2012; He et al., 2001). For previous reports on the isolation of micromelin (micromelumin) from a Northern Queensland collection, an Assamese collection, and a Northeast Thailand collection, see: Lamberton et al. (1967); Das et al. (1984); Siridechakorn et al. (2012). For detailed H1 NMR spectroscopic data, see: Das et al. (1984); Siridechakorn et al. (2012). For a phytochemical investigation, see: Siridechakorn et al. (2012). For a closely related micromelin structure, C15H12O6, see: Fun et al. (2011). For hydrogen-bond motifs, see: Bernstein et al. (1995). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound was obtained from an acetone extract of Micromelum integerrimum leaves (0.55 kg), which are collected from Chiang Rai Province, Thailand. From seven fractions (A—G) yielded by column chromatography using hexanes-acetone, the title compound (295.9 mg) was isolated from fraction D by also column chromatography using 2% acetone-CH2Cl2. The crystals were then crystallized by slowly evaporation of the solvent.

Refinement top

The carbonyl group O atom is disordered over two sets of sites in a 0.57 (8):0.43 (8) ratio.Friedel opposites were merged in the final cycles of refinement as there is no appreciable anomalous scattering at the wavelength used for data collection. H atoms were placed in geometrically idealized positions (C—H= 0.91-1.06 Å, C(methyl)—H=0.96Å and were constrained to ride on their parects atoms with Uiso(H)= 1.2Ueq(C) and 1.5Ueq(C) respectively , except H3, H4, H5, and H8, were refined freely, with isotropic displacement parameters.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2007); software used to prepare material for publication: publCIF (Westrip, 2010) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at 50% probability level.
[Figure 2] Fig. 2. A view of (I), showing the C(10) chains along [010] constructed via C—H···O hydrogen bonds. Hydrogen bonds are depicted as dashed lines [symmetry-code:(i) -x,1/2+y, 1-z]
(1R,3R,4R,6S)-4-(7-Methoxy-2-oxo-2H- chromen-6-yl)-1-methyl-3,6-dioxabicyclo[3.1.0]hexan-2-yl acetate top
Crystal data top
C17H16O7F(000) = 348
Mr = 332.31Dx = 1.388 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 3003 reflections
a = 10.4825 (16) Åθ = 1.9–28.3°
b = 6.9213 (9) ŵ = 0.11 mm1
c = 11.0212 (18) ÅT = 298 K
β = 95.970 (7)°Block, colourless
V = 795.3 (2) Å30.64 × 0.32 × 0.24 mm
Z = 2
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2123 independent reflections
Radiation source: fine-focus sealed tube1692 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ω scansθmax = 28.3°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Bruker, 1997)
h = 138
Tmin = 0.653, Tmax = 0.746k = 79
4381 measured reflectionsl = 1414
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.136H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0701P)2 + 0.1456P]
where P = (Fo2 + 2Fc2)/3
2123 reflections(Δ/σ)max < 0.001
223 parametersΔρmax = 0.47 e Å3
2 restraintsΔρmin = 0.24 e Å3
Crystal data top
C17H16O7V = 795.3 (2) Å3
Mr = 332.31Z = 2
Monoclinic, P21Mo Kα radiation
a = 10.4825 (16) ŵ = 0.11 mm1
b = 6.9213 (9) ÅT = 298 K
c = 11.0212 (18) Å0.64 × 0.32 × 0.24 mm
β = 95.970 (7)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2123 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1997)
1692 reflections with I > 2σ(I)
Tmin = 0.653, Tmax = 0.746Rint = 0.021
4381 measured reflectionsθmax = 28.3°
Refinement top
R[F2 > 2σ(F2)] = 0.0462 restraints
wR(F2) = 0.136H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.47 e Å3
2123 reflectionsΔρmin = 0.24 e Å3
223 parameters
Special details top

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 (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.09274 (16)0.0334 (4)0.56547 (17)0.0485 (5)
C20.2211 (2)0.0363 (5)0.5224 (3)0.0509 (6)
O20.2958 (2)0.0392 (4)0.5982 (2)0.0701 (7)
C30.2509 (2)0.0355 (5)0.3921 (3)0.0542 (7)
H30.335 (3)0.0402 (6)0.3602 (13)0.065*
C40.1595 (2)0.0280 (5)0.3155 (3)0.0490 (6)
H40.1858 (8)0.0256 (5)0.219 (3)0.059*
C50.0765 (2)0.0093 (4)0.2907 (2)0.0434 (6)
H50.0579 (6)0.0024 (5)0.199 (3)0.052*
C60.2015 (2)0.0050 (4)0.3416 (2)0.0438 (6)
C70.2260 (2)0.0189 (4)0.4699 (2)0.0425 (5)
O30.35235 (16)0.0218 (4)0.51324 (18)0.0587 (6)
C160.3858 (3)0.0418 (6)0.6410 (3)0.0572 (7)
H16A0.34310.15260.67020.086*
H16B0.47690.05820.65720.086*
H16C0.36000.07190.68200.086*
C80.1272 (2)0.0280 (5)0.5436 (2)0.0423 (5)
H80.1452 (6)0.0344 (5)0.633 (3)0.051*
C90.0026 (2)0.0280 (4)0.4886 (2)0.0389 (5)
C100.0266 (2)0.0232 (4)0.3624 (2)0.0408 (5)
C110.3156 (3)0.0214 (5)0.2692 (3)0.0502 (7)
H110.37880.10420.31590.060*
O110.2824 (2)0.1069 (4)0.1510 (2)0.0606 (6)
C120.3783 (3)0.1663 (6)0.2434 (3)0.0563 (8)
H120.37740.27510.30030.068*
O120.48617 (19)0.1365 (5)0.1725 (2)0.0697 (7)
C130.3647 (3)0.1984 (6)0.1116 (3)0.0621 (8)
C140.2937 (3)0.0253 (6)0.0571 (3)0.0599 (8)
H140.33960.03230.00700.072*
O130.1675 (2)0.0904 (4)0.00763 (19)0.0656 (7)
C150.3633 (4)0.3895 (9)0.0470 (4)0.0931 (14)
H15A0.27620.42890.02480.140*
H15B0.40660.37730.02520.140*
H15C0.40620.48450.10000.140*
C170.1085 (3)0.0092 (6)0.0852 (3)0.0652 (9)
C180.0245 (4)0.0466 (8)0.1189 (4)0.0793 (11)
H18A0.05470.01120.19570.119*
H18B0.03010.18470.12580.119*
H18C0.07620.00310.05730.119*
O19A0.1483 (6)0.1679 (10)0.1149 (6)0.0843 (12)*0.567 (8)
O19B0.1763 (7)0.0896 (14)0.1535 (7)0.0843 (12)*0.433 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0370 (8)0.0543 (11)0.0556 (10)0.0019 (10)0.0112 (7)0.0022 (11)
C20.0374 (12)0.0414 (14)0.0750 (18)0.0000 (13)0.0113 (12)0.0053 (16)
O20.0463 (10)0.0742 (16)0.0943 (16)0.0031 (13)0.0283 (10)0.0057 (15)
C30.0318 (11)0.0494 (15)0.0794 (19)0.0042 (14)0.0037 (11)0.0071 (17)
C40.0404 (12)0.0459 (14)0.0585 (15)0.0051 (14)0.0054 (11)0.0033 (15)
C50.0440 (12)0.0436 (14)0.0424 (12)0.0009 (12)0.0030 (10)0.0011 (12)
C60.0382 (11)0.0446 (15)0.0489 (13)0.0013 (12)0.0067 (10)0.0025 (13)
C70.0328 (10)0.0427 (13)0.0513 (13)0.0040 (12)0.0007 (9)0.0008 (13)
O30.0323 (8)0.0833 (16)0.0599 (11)0.0021 (12)0.0015 (7)0.0034 (13)
C160.0388 (12)0.0655 (19)0.0640 (16)0.0071 (15)0.0103 (11)0.0031 (17)
C80.0380 (11)0.0451 (13)0.0433 (12)0.0010 (13)0.0016 (9)0.0007 (13)
C90.0344 (10)0.0341 (11)0.0486 (12)0.0009 (12)0.0059 (9)0.0029 (12)
C100.0354 (10)0.0373 (12)0.0491 (12)0.0022 (12)0.0006 (9)0.0003 (12)
C110.0416 (13)0.0589 (18)0.0509 (14)0.0051 (13)0.0080 (11)0.0103 (13)
O110.0620 (13)0.0600 (12)0.0615 (13)0.0007 (11)0.0147 (10)0.0160 (11)
C120.0384 (13)0.075 (2)0.0578 (16)0.0085 (15)0.0171 (12)0.0156 (16)
O120.0379 (10)0.110 (2)0.0636 (13)0.0054 (12)0.0170 (9)0.0161 (14)
C130.0450 (15)0.082 (2)0.0624 (18)0.0085 (17)0.0210 (13)0.0089 (18)
C140.0442 (13)0.083 (2)0.0541 (15)0.0060 (18)0.0143 (11)0.0172 (18)
O130.0501 (11)0.0877 (18)0.0588 (12)0.0055 (11)0.0046 (9)0.0196 (12)
C150.081 (3)0.104 (3)0.099 (3)0.023 (3)0.030 (2)0.021 (3)
C170.0663 (18)0.083 (3)0.0468 (14)0.0084 (18)0.0062 (13)0.0103 (16)
C180.071 (2)0.092 (3)0.072 (2)0.001 (2)0.0103 (17)0.006 (2)
Geometric parameters (Å, º) top
O1—C91.377 (3)C11—O111.441 (3)
O1—C21.380 (3)C11—C121.496 (5)
C2—O21.203 (3)C11—H110.9800
C2—C31.438 (4)O11—C141.396 (5)
C3—C41.343 (4)C12—O121.455 (3)
C3—H30.9168C12—C131.463 (4)
C4—C101.435 (3)C12—H120.9800
C4—H41.0676O12—C131.441 (4)
C5—C61.371 (3)C13—C151.501 (7)
C5—C101.406 (3)C13—C141.502 (5)
C5—H51.0053C14—O131.450 (4)
C6—C71.413 (4)C14—H140.9800
C6—C111.517 (3)O13—C171.332 (4)
C7—O31.361 (3)C15—H15A0.9600
C7—C81.383 (3)C15—H15B0.9600
O3—C161.422 (3)C15—H15C0.9600
C16—H16A0.9600C17—O19B1.222 (7)
C16—H16B0.9600C17—O19A1.231 (7)
C16—H16C0.9600C17—C181.456 (5)
C8—C91.382 (3)C18—H18A0.9600
C8—H80.9857C18—H18B0.9600
C9—C101.393 (4)C18—H18C0.9600
C9—O1—C2122.2 (2)C6—C11—H11108.7
O2—C2—O1116.3 (3)C14—O11—C11111.7 (3)
O2—C2—C3127.2 (3)O12—C12—C1359.20 (19)
O1—C2—C3116.5 (2)O12—C12—C11111.1 (3)
C4—C3—C2122.2 (2)C13—C12—C11108.8 (3)
C4—C3—H3118.9O12—C12—H12120.8
C2—C3—H3118.9C13—C12—H12120.8
C3—C4—C10120.3 (2)C11—C12—H12120.8
C3—C4—H4119.9C13—O12—C1260.65 (19)
C10—C4—H4119.9O12—C13—C1260.14 (19)
C6—C5—C10121.9 (2)O12—C13—C15116.6 (3)
C6—C5—H5119.0C12—C13—C15126.9 (4)
C10—C5—H5119.0O12—C13—C14109.0 (3)
C5—C6—C7118.4 (2)C12—C13—C14105.6 (3)
C5—C6—C11124.1 (2)C15—C13—C14122.2 (3)
C7—C6—C11117.6 (2)O11—C14—O13109.8 (2)
O3—C7—C8123.6 (2)O11—C14—C13107.6 (3)
O3—C7—C6115.0 (2)O13—C14—C13107.3 (3)
C8—C7—C6121.4 (2)O11—C14—H14110.7
C7—O3—C16118.7 (2)O13—C14—H14110.7
O3—C16—H16A109.5C13—C14—H14110.7
O3—C16—H16B109.5C17—O13—C14117.4 (3)
H16A—C16—H16B109.5C13—C15—H15A109.5
O3—C16—H16C109.5C13—C15—H15B109.5
H16A—C16—H16C109.5H15A—C15—H15B109.5
H16B—C16—H16C109.5C13—C15—H15C109.5
C9—C8—C7118.3 (2)H15A—C15—H15C109.5
C9—C8—H8120.9H15B—C15—H15C109.5
C7—C8—H8120.9O19B—C17—O13117.1 (4)
O1—C9—C8116.3 (2)O19A—C17—O13121.5 (4)
O1—C9—C10121.2 (2)O19B—C17—C18124.5 (4)
C8—C9—C10122.5 (2)O19A—C17—C18120.7 (4)
C9—C10—C5117.4 (2)O13—C17—C18114.4 (3)
C9—C10—C4117.6 (2)C17—C18—H18A109.5
C5—C10—C4125.0 (2)C17—C18—H18B109.5
O11—C11—C12104.7 (2)H18A—C18—H18B109.5
O11—C11—C6113.3 (2)C17—C18—H18C109.5
C12—C11—C6112.4 (2)H18A—C18—H18C109.5
O11—C11—H11108.7H18B—C18—H18C109.5
C12—C11—H11108.7
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O19Ai1.07 (3)2.46 (2)3.064 (8)114 (1)
C5—H5···O131.01 (3)2.58 (3)3.403 (3)139 (1)
C12—H12···O2ii0.982.353.282 (5)158
C16—H16B···O2iii0.962.543.419 (4)153
Symmetry codes: (i) x, y+1/2, z; (ii) x, y+1/2, z+1; (iii) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O19Ai1.07 (3)2.463 (17)3.064 (8)114.4 (7)
C5—H5···O131.01 (3)2.58 (3)3.403 (3)138.7 (6)
C12—H12···O2ii0.982.353.282 (5)158
C16—H16B···O2iii0.962.543.419 (4)153
Symmetry codes: (i) x, y+1/2, z; (ii) x, y+1/2, z+1; (iii) x+1, y, z.
Acknowledgements top

The Thailand Research Fund is acknowledged for a research grant.

references
References top

Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.

Brandenburg, K. (2007). DIAMOND. Crystal Impact GbR, Bonn, Germany.

Bruker (1997). SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.

Bruker (2008). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.

Cassady, J. M., Ojima, N., Chang, C. J. & McLaughlin, J. L. (1979). J. Nat. Prod. 42, 274–278.

Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358.

Das, S., Baruah, R. H., Sharma, R. P., Barua, J. N., Kulanthaivel, P. & Herz, W. (1984). Phytochemistry, 23, 2317–2321.

Fun, H.-K., Siridechakorn, I., Laphookhieo, S. & Chantrapromma, S. (2011). Acta Cryst. E67, o1706–o1707.

He, H. P., Zou, Y., Shen, Y. M., Hao, X. Y., Zuo, G. Y. & Hao, X. J. (2001). Chin. Chem. Lett. 12, 603–606.

Lamberton, J. A., Price, J. R. & Redcliffe, A. H. (1967). Aust. J. Chem. 20, 973–979.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Siridechakorn, I., Ritthiwigrom, T. & Laphookhieo, S. (2012). Biochem. Syst. Ecol. 40, 69–70.

Spek, A. L. (2009). Acta Cryst. D65, 148–155.

Sripisut, T., Cheenpracha, S., Ritthiwigrom, T., Prawat, U. & Laphookhieo, S. (2012). Rec. Nat. Prod. 6, 386–389.

Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.