organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

3,4,5-Trimeth­­oxy-N-(2-meth­oxy­phen­yl)benzamide

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bDepartment Chemie, Fakultät für Naturwissenschaften, Universität Paderborn, Warburgerstrasse 100, D-33098 Paderborn, Germany
*Correspondence e-mail: aamersaeed@yahoo.com

(Received 13 July 2009; accepted 16 July 2009; online 22 July 2009)

In the title mol­ecule, C17H19NO5, the amide plane is oriented at an angle of 41.5 (3)° with respect to the 2-methoxy­benzene ring. The three meth­oxy groups lie almost in the plane of the aromatic rings to which they are attached [C—O—C—C torsion angles of of 0.7 (4), −13.4 (4) and 3.1 (4)°], whereas the meth­oxy group at the 4-position of the 3,4,5-trimethoxy­benzene ring is nearly perpendicularly oriented [C—O—C—C torsion angle of 103.9 (3)°]. In the crystal structure, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains along [001].

Related literature

The background of this work has been described in our earlier paper (Saeed et al. 2008[Saeed, A., Khera, R. A., Abbas, N., Simpson, J. & Stanley, R. G. (2008). Acta Cryst. E64, o1976.]). For a related structure, see: Parra et al. (2001[Parra, R. D., Zeng, H., Zhu, J., Zheng, C., Zeng, X. C. & Gong, B. (2001). Chem. Eur. J. 7, 4352-4357.]).

[Scheme 1]

Experimental

Crystal data
  • C17H19NO5

  • Mr = 317.33

  • Orthorhombic, P c a 21

  • a = 7.409 (2) Å

  • b = 22.522 (6) Å

  • c = 9.681 (3) Å

  • V = 1615.4 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 120 K

  • 0.50 × 0.44 × 0.20 mm

Data collection
  • Bruker SMART APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.953, Tmax = 0.981

  • 13253 measured reflections

  • 2050 independent reflections

  • 1902 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.126

  • S = 1.13

  • 2050 reflections

  • 216 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.895 (10) 2.182 (14) 3.066 (4) 169 (4)
Symmetry code: (i) [-x+{\script{1\over 2}}, y, z-{\script{1\over 2}}].

Data collection: SMART (Bruker, 2002[Bruker (2002). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The background of this work has been described in our earlier paper (Saeed et al. 2008).

The molecular structure of the title compound (Fig. 1) is similar to that of ICULOH (Parra et al., 2001), but with 3,4,5-methoxy substitution of the benzamide ring. Methoxy groups O2, O3 and O5 lie almost in plane of the corresponding aromatic rings with torsion angles C8–O2–C7–C6 of 0.7 (4)°, C15–O3–C11–C10 of -13.4 (4)° and C17–O5–C13–C14 of 3.1 (4)°, respectively, whereas the O4-group is nearly perpendicular oriented with C16–O4–C12–C13 of 103.9 (3)°. The two aromatic planes make a dihedral angle of 67.66 (9)° and the angle between the amide group and the 2-methoxy benzene ring is 41.5 (3)°. In the cystal structure, intermolecular N–H···O hydrogen bonds (Table 1) link the molecules into infinite chains along the [001] direction (Fig. 2).

Related literature top

The background of this work has been described in our earlier paper (Saeed et al. 2008). For a related structure, see: Parra et al. (2001).

Experimental top

3,4,5-Trimethoxybenzoyl chloride (1 mmol) in CHCl3 was treated with 2-methoxyaniline (3.5 mmol) under a nitrogen atmosphere at reflux conditions for 5 h. Upon cooling, the reaction mixture was diluted with CHCl3 and washed consecutively with 1 M aq HCl and saturated aq NaHCO3. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. Crystallization of the residue in methanol afforded the title compound (84%) as white needles: Anal. calc. for C17H19NO5: C 64.34, H 6.03, N 4.41%; found: C 64.31, H 6.09, N 4.34%

Refinement top

All H atoms were clearly identified in difference syntheses, then refined at calculated positions riding on the carbon atoms (C–H = 0.95–0.99 Å) with isotropic displacement parameters Uiso(H) = 1.2U(Ceq) or 1.5U(–CH3). All CH3 hydrogen atoms were allowed to rotate but not to tip. H(N) was refined freely with a restained (DFIX) N–H distance. The title compound crystallizes in the non-centrosymmetric space group P ca21; however, in the absence of significant anomalous scattering effects, the Flack parameter is essentially meaningless. Accordingly, Friedel pairs were merged.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Crystal packing viewed along [100] with intermolecular hydrogen bonding pattern indicated as dashed lines. H-atoms not involved in hydrogen bonding are omitted.
3,4,5-Trimethoxy-N-(2-methoxyphenyl)benzamide top
Crystal data top
C17H19NO5F(000) = 672
Mr = 317.33Dx = 1.305 Mg m3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 887 reflections
a = 7.409 (2) Åθ = 2.9–27.6°
b = 22.522 (6) ŵ = 0.10 mm1
c = 9.681 (3) ÅT = 120 K
V = 1615.4 (7) Å3Prism, colourless
Z = 40.50 × 0.44 × 0.20 mm
Data collection top
Bruker SMART APEX
diffractometer
2050 independent reflections
Radiation source: sealed tube1902 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
ϕ and ω scansθmax = 27.9°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
h = 99
Tmin = 0.953, Tmax = 0.981k = 2925
13253 measured reflectionsl = 1212
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)] = 0.051Hydrogen site location: difference Fourier map
wR(F2) = 0.126H atoms treated by a mixture of independent and constrained refinement
S = 1.13 w = 1/[σ2(Fo2) + (0.0648P)2 + 0.6933P]
where P = (Fo2 + 2Fc2)/3
2050 reflections(Δ/σ)max < 0.001
216 parametersΔρmax = 0.37 e Å3
2 restraintsΔρmin = 0.20 e Å3
Crystal data top
C17H19NO5V = 1615.4 (7) Å3
Mr = 317.33Z = 4
Orthorhombic, Pca21Mo Kα radiation
a = 7.409 (2) ŵ = 0.10 mm1
b = 22.522 (6) ÅT = 120 K
c = 9.681 (3) Å0.50 × 0.44 × 0.20 mm
Data collection top
Bruker SMART APEX
diffractometer
2050 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
1902 reflections with I > 2σ(I)
Tmin = 0.953, Tmax = 0.981Rint = 0.047
13253 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0512 restraints
wR(F2) = 0.126H atoms treated by a mixture of independent and constrained refinement
S = 1.13Δρmax = 0.37 e Å3
2050 reflectionsΔρmin = 0.20 e Å3
216 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*/Ueq
O10.1314 (3)0.22502 (9)1.0268 (2)0.0232 (5)
O20.0063 (3)0.16331 (10)0.5858 (2)0.0246 (5)
O30.7319 (3)0.33720 (9)0.7087 (2)0.0258 (5)
O40.6652 (3)0.43489 (9)0.8620 (3)0.0246 (5)
O50.4036 (3)0.43643 (9)1.0503 (3)0.0263 (5)
N10.1909 (3)0.19743 (11)0.8055 (3)0.0199 (5)
H10.232 (7)0.2095 (18)0.723 (3)0.053 (13)*
C10.2067 (3)0.23480 (13)0.9166 (3)0.0186 (6)
C20.0968 (3)0.14253 (13)0.8110 (3)0.0189 (6)
C30.1076 (4)0.10537 (14)0.9251 (4)0.0242 (6)
H3A0.18040.11631.00180.029*
C40.0117 (4)0.05177 (14)0.9278 (4)0.0285 (7)
H4A0.01790.02681.00680.034*
C50.0923 (4)0.03511 (14)0.8150 (4)0.0294 (7)
H5A0.15750.00120.81690.035*
C60.1012 (4)0.07152 (14)0.6989 (4)0.0270 (7)
H6A0.17180.05980.62170.032*
C70.0069 (4)0.12518 (13)0.6956 (3)0.0211 (6)
C80.1114 (5)0.14694 (18)0.4675 (4)0.0382 (9)
H8A0.06810.10890.43120.057*
H8B0.09960.17760.39610.057*
H8C0.23850.14320.49420.057*
C90.3260 (4)0.28794 (12)0.8974 (3)0.0167 (5)
C100.4689 (4)0.28683 (13)0.8036 (3)0.0183 (5)
H10A0.48590.25320.74570.022*
C110.5872 (4)0.33511 (13)0.7945 (3)0.0181 (5)
C120.5583 (4)0.38548 (13)0.8771 (3)0.0204 (6)
C130.4143 (4)0.38603 (12)0.9724 (3)0.0194 (6)
C140.2986 (4)0.33723 (12)0.9835 (3)0.0190 (6)
H14A0.20260.33741.04860.023*
C150.7858 (5)0.28235 (14)0.6464 (4)0.0328 (8)
H15A0.79790.25180.71790.049*
H15B0.90190.28770.59950.049*
H15C0.69450.27000.57900.049*
C160.8392 (5)0.42964 (16)0.9272 (5)0.0367 (9)
H16A0.82340.42551.02730.055*
H16B0.91090.46520.90770.055*
H16C0.90180.39460.89110.055*
C170.2685 (5)0.43817 (14)1.1558 (4)0.0323 (7)
H17A0.14870.43521.11350.048*
H17B0.27790.47571.20670.048*
H17C0.28650.40491.21950.048*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0229 (10)0.0307 (11)0.0159 (10)0.0039 (8)0.0057 (9)0.0036 (9)
O20.0247 (11)0.0311 (11)0.0179 (10)0.0079 (9)0.0033 (8)0.0018 (9)
O30.0239 (10)0.0295 (10)0.0242 (12)0.0046 (9)0.0100 (10)0.0015 (9)
O40.0241 (10)0.0229 (11)0.0268 (11)0.0044 (8)0.0023 (9)0.0033 (9)
O50.0285 (11)0.0234 (10)0.0270 (13)0.0027 (8)0.0081 (10)0.0053 (9)
N10.0205 (11)0.0271 (12)0.0121 (11)0.0043 (9)0.0007 (10)0.0019 (10)
C10.0142 (12)0.0266 (14)0.0150 (13)0.0016 (10)0.0024 (10)0.0014 (11)
C20.0150 (12)0.0240 (14)0.0176 (14)0.0001 (10)0.0058 (11)0.0033 (12)
C30.0207 (14)0.0289 (15)0.0231 (16)0.0044 (11)0.0028 (12)0.0002 (12)
C40.0266 (15)0.0269 (15)0.0320 (18)0.0057 (12)0.0090 (14)0.0062 (14)
C50.0242 (14)0.0203 (14)0.044 (2)0.0035 (11)0.0069 (15)0.0030 (14)
C60.0223 (14)0.0281 (15)0.0307 (18)0.0025 (12)0.0014 (13)0.0079 (13)
C70.0180 (13)0.0242 (14)0.0211 (15)0.0006 (11)0.0042 (11)0.0033 (12)
C80.0381 (19)0.049 (2)0.0276 (18)0.0158 (16)0.0144 (16)0.0038 (17)
C90.0160 (12)0.0243 (13)0.0098 (12)0.0004 (10)0.0027 (10)0.0004 (10)
C100.0207 (12)0.0245 (13)0.0098 (12)0.0018 (10)0.0005 (11)0.0018 (11)
C110.0163 (11)0.0272 (14)0.0107 (13)0.0006 (10)0.0026 (10)0.0014 (11)
C120.0223 (13)0.0218 (14)0.0171 (14)0.0000 (11)0.0036 (11)0.0038 (11)
C130.0197 (13)0.0228 (14)0.0156 (14)0.0015 (10)0.0031 (11)0.0001 (12)
C140.0178 (12)0.0275 (14)0.0118 (12)0.0025 (10)0.0008 (11)0.0007 (11)
C150.0301 (17)0.0315 (15)0.0368 (19)0.0044 (12)0.0173 (16)0.0034 (16)
C160.0308 (17)0.0338 (19)0.045 (2)0.0093 (14)0.0069 (17)0.0000 (16)
C170.0352 (17)0.0316 (15)0.0300 (18)0.0030 (14)0.0107 (16)0.0127 (15)
Geometric parameters (Å, º) top
O1—C11.224 (4)C6—H6A0.9500
O2—C71.366 (4)C8—H8A0.9800
O2—C81.434 (4)C8—H8B0.9800
O3—C111.357 (3)C8—H8C0.9800
O3—C151.432 (4)C9—C101.395 (4)
O4—C121.374 (4)C9—C141.403 (4)
O4—C161.441 (4)C10—C111.400 (4)
O5—C131.365 (4)C10—H10A0.9500
O5—C171.431 (4)C11—C121.404 (4)
N1—C11.371 (4)C12—C131.410 (4)
N1—C21.420 (4)C13—C141.398 (4)
N1—H10.895 (10)C14—H14A0.9500
C1—C91.500 (4)C15—H15A0.9800
C2—C31.388 (4)C15—H15B0.9800
C2—C71.412 (4)C15—H15C0.9800
C3—C41.401 (5)C16—H16A0.9800
C3—H3A0.9500C16—H16B0.9800
C4—C51.389 (5)C16—H16C0.9800
C4—H4A0.9500C17—H17A0.9800
C5—C61.392 (5)C17—H17B0.9800
C5—H5A0.9500C17—H17C0.9800
C6—C71.396 (4)
C7—O2—C8117.3 (2)C10—C9—C1120.9 (2)
C11—O3—C15116.7 (2)C14—C9—C1118.2 (2)
C12—O4—C16113.8 (3)C9—C10—C11120.1 (3)
C13—O5—C17117.3 (2)C9—C10—H10A119.9
C1—N1—C2123.1 (2)C11—C10—H10A119.9
C1—N1—H1119 (3)O3—C11—C10124.1 (3)
C2—N1—H1118 (3)O3—C11—C12116.2 (2)
O1—C1—N1122.3 (3)C10—C11—C12119.8 (3)
O1—C1—C9121.4 (3)O4—C12—C11120.4 (3)
N1—C1—C9116.3 (2)O4—C12—C13119.9 (3)
C3—C2—C7119.7 (3)C11—C12—C13119.7 (3)
C3—C2—N1121.8 (3)O5—C13—C14125.1 (3)
C7—C2—N1118.6 (3)O5—C13—C12114.4 (2)
C2—C3—C4120.3 (3)C14—C13—C12120.5 (3)
C2—C3—H3A119.8C13—C14—C9119.1 (3)
C4—C3—H3A119.8C13—C14—H14A120.4
C5—C4—C3120.0 (3)C9—C14—H14A120.4
C5—C4—H4A120.0O3—C15—H15A109.5
C3—C4—H4A120.0O3—C15—H15B109.5
C4—C5—C6120.1 (3)H15A—C15—H15B109.5
C4—C5—H5A119.9O3—C15—H15C109.5
C6—C5—H5A119.9H15A—C15—H15C109.5
C5—C6—C7120.3 (3)H15B—C15—H15C109.5
C5—C6—H6A119.8O4—C16—H16A109.5
C7—C6—H6A119.8O4—C16—H16B109.5
O2—C7—C6124.3 (3)H16A—C16—H16B109.5
O2—C7—C2116.1 (2)O4—C16—H16C109.5
C6—C7—C2119.6 (3)H16A—C16—H16C109.5
O2—C8—H8A109.5H16B—C16—H16C109.5
O2—C8—H8B109.5O5—C17—H17A109.5
H8A—C8—H8B109.5O5—C17—H17B109.5
O2—C8—H8C109.5H17A—C17—H17B109.5
H8A—C8—H8C109.5O5—C17—H17C109.5
H8B—C8—H8C109.5H17A—C17—H17C109.5
C10—C9—C14120.7 (3)H17B—C17—H17C109.5
C2—N1—C1—O14.4 (4)C1—C9—C10—C11175.1 (3)
C2—N1—C1—C9174.0 (2)C15—O3—C11—C1013.4 (4)
C1—N1—C2—C339.8 (4)C15—O3—C11—C12167.1 (3)
C1—N1—C2—C7141.6 (3)C9—C10—C11—O3178.4 (3)
C7—C2—C3—C42.0 (4)C9—C10—C11—C122.0 (4)
N1—C2—C3—C4179.4 (3)C16—O4—C12—C1178.5 (4)
C2—C3—C4—C51.1 (5)C16—O4—C12—C13103.9 (3)
C3—C4—C5—C60.1 (5)O3—C11—C12—O44.5 (4)
C4—C5—C6—C70.5 (5)C10—C11—C12—O4175.1 (3)
C8—O2—C7—C60.7 (4)O3—C11—C12—C13177.9 (3)
C8—O2—C7—C2179.6 (3)C10—C11—C12—C132.5 (4)
C5—C6—C7—O2179.2 (3)C17—O5—C13—C143.1 (4)
C5—C6—C7—C20.4 (4)C17—O5—C13—C12175.6 (3)
C3—C2—C7—O2178.0 (2)O4—C12—C13—O54.6 (4)
N1—C2—C7—O20.6 (4)C11—C12—C13—O5177.7 (3)
C3—C2—C7—C61.7 (4)O4—C12—C13—C14176.6 (3)
N1—C2—C7—C6179.7 (3)C11—C12—C13—C141.1 (4)
O1—C1—C9—C10151.4 (3)O5—C13—C14—C9179.5 (3)
N1—C1—C9—C1027.1 (4)C12—C13—C14—C90.8 (4)
O1—C1—C9—C1424.0 (4)C10—C9—C14—C131.3 (4)
N1—C1—C9—C14157.6 (2)C1—C9—C14—C13176.7 (2)
C14—C9—C10—C110.1 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.90 (1)2.18 (1)3.066 (4)169 (4)
Symmetry code: (i) x+1/2, y, z1/2.

Experimental details

Crystal data
Chemical formulaC17H19NO5
Mr317.33
Crystal system, space groupOrthorhombic, Pca21
Temperature (K)120
a, b, c (Å)7.409 (2), 22.522 (6), 9.681 (3)
V3)1615.4 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.50 × 0.44 × 0.20
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.953, 0.981
No. of measured, independent and
observed [I > 2σ(I)] reflections
13253, 2050, 1902
Rint0.047
(sin θ/λ)max1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.126, 1.13
No. of reflections2050
No. of parameters216
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.37, 0.20

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.895 (10)2.182 (14)3.066 (4)169 (4)
Symmetry code: (i) x+1/2, y, z1/2.
 

Acknowledgements

AS gratefully acknowledges a reasearch grant from Quaid-i-Azam University, Islamabad, under the URF project.

References

First citationBruker (2002). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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