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In the stable polymorph of the title compound, C17H19NO3 [systematic name: (5α,6α)-7,8-didehydro-4,5-ep­oxy-17-methyl­morphinan-3,6-diol], the mol­ecular conformation is in agreement with the characteristics of previously reported morphine forms. The molecule displays the typical T-shape and its piperidine ring adopts a slightly distorted chair conformation. Inter­molecular O—H...O hydrogen bonds link the mol­ecules into helical chains parallel to the b axis. Intra­molecular O—H...O hydrogen bonds are also observed.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536812048945/im2413sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536812048945/im2413Isup2.hkl
Contains datablock I

CCDC reference: 920204

Key indicators

  • Single-crystal X-ray study
  • T = 173 K
  • Mean [sigma](C-C) = 0.009 Å
  • R factor = 0.068
  • wR factor = 0.141
  • Data-to-parameter ratio = 7.3

checkCIF/PLATON results

No syntax errors found



Alert level C PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) ..... 7.33 PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds ............... 0.0089 Ang PLAT906_ALERT_3_C Large K value in the Analysis of Variance ...... 2.886 PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L= 0.600 15
Alert level G PLAT005_ALERT_5_G No _iucr_refine_instructions_details in the CIF ? PLAT007_ALERT_5_G Note: Number of Unrefined D-H Atoms ............ 2 PLAT791_ALERT_4_G Note: The Model has Chirality at C5 (Verify) S PLAT791_ALERT_4_G Note: The Model has Chirality at C6 (Verify) R PLAT791_ALERT_4_G Note: The Model has Chirality at C9 (Verify) R PLAT791_ALERT_4_G Note: The Model has Chirality at C13 (Verify) S PLAT791_ALERT_4_G Note: The Model has Chirality at C14 (Verify) R PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L= 0.600 14
0 ALERT level A = Most likely a serious problem - resolve or explain 0 ALERT level B = A potentially serious problem, consider carefully 4 ALERT level C = Check. Ensure it is not caused by an omission or oversight 8 ALERT level G = General information/check it is not something unexpected 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 4 ALERT type 3 Indicator that the structure quality may be low 6 ALERT type 4 Improvement, methodology, query or suggestion 2 ALERT type 5 Informative message, check

Comment top

Morphine is the main alkaloid of opium, the dried latex of the opium poppy (Papaver somniferum). The Cambridge Structural Database (CSD; version 5.33 and updates; Allen, 2002) contains a number of free base and salt structures of morphine: a monohydrate (Bye, 1976), a hydrochloride trihydrate (Gylbert, 1973), a hydroiodide dihydrate (Mackay & Hodgkin, 1955), a complex with β-phenylhydracrylic acid (Lutz & Spek, 1998) and a bis(morphinium) dihydrogensulfate pentahydrate (Wongweichintana et al., 1984). A hydrochloride anhydrate structure was recently reported by us (Gelbrich et al., 2012). The title structure was previously solved from powder data by Guguta et al. (2008), however the corresponding atomic coordinates are not available from the CSD or from supplementary materials accompanying this report.

According to Kofler (1933), morphine can exist in two distinct polymorphic modifications, and the characteristics of the crystals investigated by us match Kofler's description of the stable form. Our thermomicroscopy experiments have shown that the investigated crystals melt under decomposition at 254 °C (the applied heating rate was 5 °C per minute). This behaviour is in agreement with reports given by Kofler (1933) and Kuhnert-Brandstätter et al. (1975).

The geometry of the molecular morphine scaffold (Figure 1) with its five rings agrees with the characteristics of the related salt and free base structures mentioned above. The title structure displays two sets of O—H···O bonds, one of which is intramolecular and the other is intermolecular (Table 1). Intermolecular hydrogen bonds link the morphine molecules into an infinite helical chain that propagates parallel to the b-axis (Figure 2).

The packing of the geometrically inflexible morphine moieties in the title structure was compared with corresponding packing arrangements present in the six morphine forms mentioned above (Bye, 1976; Gelbrich et al., 2012; Gylbert, 1973; Mackay & Hodgkin, 1955; Lutz & Spek, 1998; Wongweichintana et al., 1984), using the program XPac (Gelbrich & Hursthouse, 2005). These comparisons have shown that the packing mode of morphine molecules in the stable form is unique and has no supramolecular constructs in common with any of the other structures in this group.

Related literature top

For related structures, see: Guguta et al. (2008); Gylbert (1973); Mackay & Hodgkin (1955); Bye (1976); Wongweichintana et al. (1984); Lutz & Spek (1998); Scheins et al. (2005); Gelbrich et al. (2012). For decriptions of morphine polymorphs, see: Kofler (1933); Kuhnert-Brandstätter et al. (1975). For a description of the Cambridge Structural Database, see: Allen (2002). For the program XPac, see: Gelbrich & Hursthouse (2005).

Experimental top

Morphine was obtained from Heilmittelwerke Wien, Austria. Very thin, plate-shaped crystals of the stable polymorph were yielded from a sublimation experiment carried out on a Kofler hot bench at approximately 150 °C, using two glass slides separated by a spacer ring of 1 cm height.

Refinement top

All H atoms were identified in a difference map. Methyl H atoms were idealized and included as rigid groups allowed to rotate but not tip (C—H = 0.98 Å) and H atoms bonded to oxygen atoms (O—H = 0.84 Å), tertiary CH (C—H = 0.99 Å), secondary CH2 (C—H = 0.99 Å) and aromatic carbon atoms (C—H = 0.95 Å) were positioned geometrically. The temperature parameters of the methyl H atoms were set to Uiso(H) = 1.5 Ueq(C) of the parent carbon atom, for all other H atoms they were set to Uiso(H) = 1.2 Ueq(C or O).

Structure description top

Morphine is the main alkaloid of opium, the dried latex of the opium poppy (Papaver somniferum). The Cambridge Structural Database (CSD; version 5.33 and updates; Allen, 2002) contains a number of free base and salt structures of morphine: a monohydrate (Bye, 1976), a hydrochloride trihydrate (Gylbert, 1973), a hydroiodide dihydrate (Mackay & Hodgkin, 1955), a complex with β-phenylhydracrylic acid (Lutz & Spek, 1998) and a bis(morphinium) dihydrogensulfate pentahydrate (Wongweichintana et al., 1984). A hydrochloride anhydrate structure was recently reported by us (Gelbrich et al., 2012). The title structure was previously solved from powder data by Guguta et al. (2008), however the corresponding atomic coordinates are not available from the CSD or from supplementary materials accompanying this report.

According to Kofler (1933), morphine can exist in two distinct polymorphic modifications, and the characteristics of the crystals investigated by us match Kofler's description of the stable form. Our thermomicroscopy experiments have shown that the investigated crystals melt under decomposition at 254 °C (the applied heating rate was 5 °C per minute). This behaviour is in agreement with reports given by Kofler (1933) and Kuhnert-Brandstätter et al. (1975).

The geometry of the molecular morphine scaffold (Figure 1) with its five rings agrees with the characteristics of the related salt and free base structures mentioned above. The title structure displays two sets of O—H···O bonds, one of which is intramolecular and the other is intermolecular (Table 1). Intermolecular hydrogen bonds link the morphine molecules into an infinite helical chain that propagates parallel to the b-axis (Figure 2).

The packing of the geometrically inflexible morphine moieties in the title structure was compared with corresponding packing arrangements present in the six morphine forms mentioned above (Bye, 1976; Gelbrich et al., 2012; Gylbert, 1973; Mackay & Hodgkin, 1955; Lutz & Spek, 1998; Wongweichintana et al., 1984), using the program XPac (Gelbrich & Hursthouse, 2005). These comparisons have shown that the packing mode of morphine molecules in the stable form is unique and has no supramolecular constructs in common with any of the other structures in this group.

For related structures, see: Guguta et al. (2008); Gylbert (1973); Mackay & Hodgkin (1955); Bye (1976); Wongweichintana et al. (1984); Lutz & Spek (1998); Scheins et al. (2005); Gelbrich et al. (2012). For decriptions of morphine polymorphs, see: Kofler (1933); Kuhnert-Brandstätter et al. (1975). For a description of the Cambridge Structural Database, see: Allen (2002). For the program XPac, see: Gelbrich & Hursthouse (2005).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2003); cell refinement: CrysAlis PRO (Oxford Diffraction, 2003); data reduction: CrysAlis PRO (Oxford Diffraction, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Bruker, 1998) and Mercury (Bruno et al., 2002); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Molcular structure of morphine with displacement ellipsoids are drawn at the 50% probability level and hydrogen atoms shown as spheres of arbitrary size.
[Figure 2] Fig. 2. Hydrogen bonded helical chain. Intramolecular and intermolecular O—H···O bonds are drawn as broken lines; H and O atoms involved in hydrogen bonding are drawn as balls [symmetry code: (i) -x, y + 1/2, -z + 3/2.].
(5α,6α)-7,8-Didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol top
Crystal data top
C17H19NO3F(000) = 608
Mr = 285.33Dx = 1.407 Mg m3
Orthorhombic, P212121Cu Kα radiation, λ = 1.54180 Å
Hall symbol: P 2ac 2abCell parameters from 1360 reflections
a = 7.6989 (10) Åθ = 3.2–68.2°
b = 12.737 (4) ŵ = 0.78 mm1
c = 13.740 (4) ÅT = 173 K
V = 1347.4 (6) Å3Plate, colourless
Z = 40.15 × 0.10 × 0.03 mm
Data collection top
Oxford Diffraction Xcalibur (Ruby, Gemini ultra)
diffractometer
1408 independent reflections
Radiation source: Enhance (Mo) X-ray Source977 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.118
Detector resolution: 10.3575 pixels mm-1θmax = 68.2°, θmin = 4.7°
ω scansh = 98
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2003)
k = 1415
Tmin = 0.624, Tmax = 1.000l = 1616
13009 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.068H-atom parameters constrained
wR(F2) = 0.141 w = 1/[σ2(Fo2) + (0.0112P)2 + 2.P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
1408 reflectionsΔρmax = 0.27 e Å3
192 parametersΔρmin = 0.26 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0043 (4)
Crystal data top
C17H19NO3V = 1347.4 (6) Å3
Mr = 285.33Z = 4
Orthorhombic, P212121Cu Kα radiation
a = 7.6989 (10) ŵ = 0.78 mm1
b = 12.737 (4) ÅT = 173 K
c = 13.740 (4) Å0.15 × 0.10 × 0.03 mm
Data collection top
Oxford Diffraction Xcalibur (Ruby, Gemini ultra)
diffractometer
1408 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2003)
977 reflections with I > 2σ(I)
Tmin = 0.624, Tmax = 1.000Rint = 0.118
13009 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0680 restraints
wR(F2) = 0.141H-atom parameters constrained
S = 1.01Δρmax = 0.27 e Å3
1408 reflectionsΔρmin = 0.26 e Å3
192 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.

The Flack x parameter (Flack, 1983) and the Hooft y parameter (Hooft et al., 2008) were both indeterminate due to a lack of significant resonant scattering. Accordingly, Friedel opposites were merged prior to the final refinement. [Flack, H. D. (1983). Acta Cryst. A39, 876–881; Hooft, R. W. W., Straver, L. H. & Spek, A. L. (2008). J. Appl. Cryst. 41, 96–103.]

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.0998 (5)0.6564 (3)0.7856 (3)0.0520 (12)
H10.04310.71030.77050.062*
O20.3165 (5)0.4742 (3)0.7958 (3)0.0466 (11)
O30.1429 (6)0.2969 (3)0.7838 (3)0.0546 (12)
H30.10960.35870.79410.066*
N10.8422 (6)0.4378 (4)0.5555 (4)0.0492 (14)
C10.3549 (8)0.6662 (5)0.5563 (5)0.0458 (15)
H1A0.36110.70680.49840.055*
C20.2382 (8)0.6935 (5)0.6290 (5)0.0466 (16)
H20.16650.75340.61980.056*
C30.2223 (7)0.6362 (5)0.7147 (5)0.0429 (15)
C40.3281 (7)0.5499 (4)0.7238 (5)0.0408 (14)
C50.2959 (8)0.2985 (5)0.7233 (5)0.0494 (17)
H50.35540.22930.73200.059*
C60.4208 (7)0.3836 (5)0.7615 (5)0.0462 (16)
H60.49020.35480.81680.055*
C70.2554 (9)0.3091 (5)0.6180 (5)0.0499 (17)
H70.13980.29800.59610.060*
C80.3781 (9)0.3338 (5)0.5537 (5)0.0506 (17)
H80.35240.33400.48610.061*
C90.6652 (8)0.4267 (5)0.5160 (5)0.0450 (15)
H90.67480.38410.45510.054*
C100.5732 (8)0.5321 (5)0.4878 (5)0.0491 (17)
H10A0.66300.58380.46860.059*
H10B0.49840.51940.43040.059*
C110.4634 (7)0.5792 (5)0.5682 (4)0.0410 (14)
C120.4530 (7)0.5257 (5)0.6546 (4)0.0386 (14)
C130.5465 (8)0.4258 (5)0.6810 (4)0.0415 (15)
C140.5584 (8)0.3617 (5)0.5888 (5)0.0466 (16)
H140.62270.29530.60330.056*
C150.7290 (7)0.4477 (5)0.7212 (5)0.0443 (15)
H15A0.71990.49480.77830.053*
H15B0.78180.38090.74320.053*
C160.8453 (8)0.4978 (5)0.6457 (5)0.0521 (17)
H16A0.80560.57040.63290.062*
H16B0.96570.50120.67080.062*
C170.9652 (8)0.4788 (6)0.4841 (5)0.060 (2)
H17A0.93350.55100.46720.090*
H17B0.96210.43500.42540.090*
H17C1.08260.47780.51170.090*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.040 (2)0.053 (2)0.063 (3)0.012 (2)0.008 (2)0.002 (2)
O20.031 (2)0.048 (2)0.060 (3)0.0019 (19)0.004 (2)0.000 (2)
O30.040 (2)0.050 (2)0.074 (3)0.006 (2)0.014 (3)0.002 (2)
N10.026 (2)0.063 (3)0.059 (3)0.001 (3)0.005 (2)0.003 (3)
C10.040 (3)0.043 (3)0.055 (4)0.003 (3)0.002 (3)0.006 (3)
C20.035 (3)0.044 (3)0.061 (5)0.008 (3)0.004 (3)0.000 (3)
C30.027 (3)0.047 (3)0.055 (4)0.003 (3)0.003 (3)0.003 (3)
C40.025 (3)0.046 (3)0.051 (4)0.000 (3)0.001 (3)0.000 (3)
C50.034 (3)0.048 (4)0.066 (5)0.006 (3)0.009 (3)0.001 (3)
C60.030 (3)0.048 (4)0.061 (4)0.000 (3)0.001 (3)0.003 (3)
C70.039 (3)0.047 (4)0.064 (5)0.005 (3)0.006 (3)0.005 (3)
C80.044 (3)0.052 (4)0.056 (4)0.005 (3)0.003 (3)0.008 (3)
C90.037 (3)0.048 (4)0.050 (4)0.004 (3)0.003 (3)0.003 (3)
C100.040 (3)0.058 (4)0.050 (4)0.008 (3)0.007 (3)0.006 (3)
C110.030 (3)0.047 (3)0.045 (4)0.004 (3)0.003 (3)0.006 (3)
C120.024 (3)0.044 (3)0.048 (4)0.002 (3)0.003 (3)0.001 (3)
C130.030 (3)0.046 (3)0.048 (4)0.000 (3)0.002 (3)0.000 (3)
C140.038 (3)0.038 (3)0.065 (5)0.001 (3)0.001 (3)0.002 (3)
C150.032 (3)0.051 (4)0.050 (4)0.001 (3)0.005 (3)0.000 (3)
C160.028 (3)0.064 (4)0.064 (4)0.003 (3)0.000 (3)0.000 (4)
C170.033 (3)0.080 (5)0.066 (5)0.000 (4)0.008 (3)0.008 (4)
Geometric parameters (Å, º) top
O1—C31.380 (7)C7—H70.9500
O1—H10.8400C8—C141.512 (9)
O2—C41.385 (7)C8—H80.9500
O2—C61.483 (7)C9—C141.538 (9)
O3—C51.442 (8)C9—C101.566 (9)
O3—H30.8400C9—H91.0000
N1—C161.456 (8)C10—C111.516 (8)
N1—C171.460 (8)C10—H10A0.9900
N1—C91.474 (8)C10—H10B0.9900
C1—C21.387 (9)C11—C121.371 (8)
C1—C111.397 (8)C12—C131.507 (8)
C1—H1A0.9500C13—C141.511 (9)
C2—C31.390 (9)C13—C151.535 (8)
C2—H20.9500C14—H141.0000
C3—C41.374 (8)C15—C161.512 (8)
C4—C121.387 (8)C15—H15A0.9900
C5—C71.486 (9)C15—H15B0.9900
C5—C61.542 (8)C16—H16A0.9900
C5—H51.0000C16—H16B0.9900
C6—C131.563 (9)C17—H17A0.9800
C6—H61.0000C17—H17B0.9800
C7—C81.331 (9)C17—H17C0.9800
C3—O1—H1109.5C11—C10—C9114.3 (5)
C4—O2—C6106.2 (4)C11—C10—H10A108.7
C5—O3—H3109.5C9—C10—H10A108.7
C16—N1—C17112.0 (5)C11—C10—H10B108.7
C16—N1—C9112.2 (5)C9—C10—H10B108.7
C17—N1—C9112.7 (5)H10A—C10—H10B107.6
C2—C1—C11120.1 (6)C12—C11—C1117.4 (6)
C2—C1—H1A119.9C12—C11—C10117.9 (5)
C11—C1—H1A119.9C1—C11—C10124.2 (6)
C1—C2—C3122.3 (6)C11—C12—C4121.6 (5)
C1—C2—H2118.8C11—C12—C13126.9 (5)
C3—C2—H2118.8C4—C12—C13110.7 (5)
C4—C3—O1119.3 (6)C12—C13—C14106.5 (5)
C4—C3—C2116.4 (6)C12—C13—C15111.7 (5)
O1—C3—C2124.1 (5)C14—C13—C15110.1 (5)
C3—C4—O2125.7 (5)C12—C13—C699.5 (5)
C3—C4—C12121.7 (6)C14—C13—C6116.4 (5)
O2—C4—C12112.4 (5)C15—C13—C6112.0 (5)
O3—C5—C7113.0 (5)C13—C14—C8109.8 (5)
O3—C5—C6108.9 (5)C13—C14—C9106.7 (5)
C7—C5—C6113.5 (5)C8—C14—C9114.2 (6)
O3—C5—H5107.0C13—C14—H14108.7
C7—C5—H5107.0C8—C14—H14108.7
C6—C5—H5107.0C9—C14—H14108.7
O2—C6—C5108.5 (5)C16—C15—C13111.9 (5)
O2—C6—C13107.1 (5)C16—C15—H15A109.2
C5—C6—C13112.8 (5)C13—C15—H15A109.2
O2—C6—H6109.5C16—C15—H15B109.2
C5—C6—H6109.5C13—C15—H15B109.2
C13—C6—H6109.5H15A—C15—H15B107.9
C8—C7—C5121.3 (6)N1—C16—C15110.7 (5)
C8—C7—H7119.4N1—C16—H16A109.5
C5—C7—H7119.4C15—C16—H16A109.5
C7—C8—C14119.7 (6)N1—C16—H16B109.5
C7—C8—H8120.1C15—C16—H16B109.5
C14—C8—H8120.1H16A—C16—H16B108.1
N1—C9—C14107.8 (5)N1—C17—H17A109.5
N1—C9—C10115.3 (5)N1—C17—H17B109.5
C14—C9—C10112.4 (5)H17A—C17—H17B109.5
N1—C9—H9107.0N1—C17—H17C109.5
C14—C9—H9107.0H17A—C17—H17C109.5
C10—C9—H9107.0H17B—C17—H17C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O3i0.841.962.757 (6)159
O3—H3···O20.842.172.629 (6)114
Symmetry code: (i) x, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC17H19NO3
Mr285.33
Crystal system, space groupOrthorhombic, P212121
Temperature (K)173
a, b, c (Å)7.6989 (10), 12.737 (4), 13.740 (4)
V3)1347.4 (6)
Z4
Radiation typeCu Kα
µ (mm1)0.78
Crystal size (mm)0.15 × 0.10 × 0.03
Data collection
DiffractometerOxford Diffraction Xcalibur (Ruby, Gemini ultra)
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2003)
Tmin, Tmax0.624, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
13009, 1408, 977
Rint0.118
(sin θ/λ)max1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.068, 0.141, 1.01
No. of reflections1408
No. of parameters192
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.27, 0.26

Computer programs: CrysAlis PRO (Oxford Diffraction, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Bruker, 1998) and Mercury (Bruno et al., 2002), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O3i0.841.962.757 (6)159.4
O3—H3···O20.842.172.629 (6)114.4
Symmetry code: (i) x, y+1/2, z+3/2.
 

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