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The title compound, C20H21ClN2O5, has potential calcium modulatory properties. The 1,4-di­hydro­pyridine ring has the usual shallow boat conformation. The 2-chloro-5-nitro­phenyl ring is oriented such that the chloro substituent is in a synperiplanar orientation with respect to the 1,4-di­hydro­pyridine ring plane, while the nitro substituent sits over the 1,4-di­hydro­pyridine ring. The cyclo­hexenone ring has a conformation that is approximately half-way between that of an envelope and that of a half-chair. The mol­ecules are linked into chains by intermolecular N-H...O hydrogen bonds.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104019468/sk1759sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270104019468/sk1759Isup2.hkl
Contains datablock I

CCDC reference: 254921

Comment top

A wide group of chemical substances influences the flow of Ca2+ ions through the channels found in cell membranes. While some compounds, the calcium agonists, activate this flow, other compounds, the calcium antagonists, selectively inhibit the flow of Ca2+ ions through the Ca2+– conducting channels (Nayler,1988). 1,4-Dihydropyridine (1,4-DHP) derivatives have yielded many drugs that act as calcium-channel agonists. Nifedipine is the prototype of this group, and both it and its structural analogues are used as antianginal and antihypertensive drugs (Janis & Triggle, 1984). Many active derivatives have been synthesized by making various modifications to the nifedipine structure, which yield compounds with calcium agonist or antagonist properties (Rose, 1989, 1990). It is thought that the activity displayed by these compounds may be influenced by their stereochemistry (Langs & Triggle, 1985). Our interest is in the structure and calcium antagonistic behaviour of condensed derivatives of 1,4-DHP. The crystal structures of some of these derivatives have already been reported (Linden et al., 1998, 2002; Şimşek et al., 2000), and the title compound, (I), has been prepared as a further potentially active 1,4-DHP derivative. The structure of (I) was confirmed by IR, 1H NMR and 13C NMR. Details of the synthesis of this compound and its antagonistic activity will be published elsewhere. The determination of its three-dimensional conformation, presented here, is important in order to obtain further insight into the structure–activity relationships of these compounds.

The 1,4-DHP ring in the structure of (I) (see Fig. 1) has a shallow boat conformation, atoms N1 and C4 lying 0.115 (2) and 0.283 (2) Å, respectively, from the plane defined by atoms C2, C3, C4a and C8a. The shallowness of the boat is indicated by the puckering parameters (Cremer & Pople, 1975): Q = 0.2356 (15) Å, θ = 73.6 (4)° and ϕ2 = 180.2 (4)° for the atom sequence N1—C2—C3—C4—C4a—C8a. For an ideal boat, θ and ϕ2 are 90° and n × 60°, respectively. The conformations of 4-aryl-1,4-DHP rings have been discussed previously (Goldmann & Stoltefuss, 1991; Linden et al. 1998, 2002; Şimşek et al., 2000) and it is usual for the ring to have a shallow boat conformation, although considerable variation in the shallowness of the boat is evident. The deviation of atom C4 in (I) corresponds to the values of around 0.30 Å found most frequently for this atom in 1,4-DHP rings (Şimşek et al., 2000). The deviations shown by atom N1 are generally smaller and spread fairly evenly over the range 0.00–0.19 Å (Linden et al., 2000, 2002). The deviation shown by atom N1 in (I) falls right in the middle of this range. In contrast, the 1,4-DHP ring in N,N-diethyl- 2,6,6-trimethyl-4-(3-nitrophenyl)-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3- carboxamide was found to be completely planar (Linden et al., 2002).

Another measure of the planarity of 1,4-DHP rings is the sum of the magnitudes of the six intraring torsion angles, P, around the ring (Fossheim et al., 1988). For (I), P is 82 (1)°, which is close to the mean value of 77 (2)° found previously for reported 1,4-DHP rings (Linden et al., 2002), although the P values generally vary over a wide range from 4 to 130°. For nifedipine itself, P is 72° (Miyamae et al., 1986).

The plane of the 2-chloro-5-nitrophenyl ring of (I) is almost parallel to the N1···C4 axis, with a N1···C4—C13—C18 torsion angle of 2.53 (15)°. This value is quite normal; the corresponding torsion angle in related structures is clustered around 0° and rarely exceeds ±30° (Linden et al., 2002). The chloro substituent lies above the C4—H bond in a synperiplanar orientation, while the nitro substituent sits over the 1,4-DHP ring. Examples of 2,5-disubstitution in the phenyl ring of 4-aryl-1,4-DHP compounds are rare, but the same 2-chloro-5-nitrophenyl ring appears in the analogous compound, dimethyl 4-(2-chloro-5-nitrophenyl)-1,4-dihydro-2,6- dimethyl-pyridine-3,5-dicarboxylate (Rovnyak et al., 1988). The orientation of the phenyl ring in this latter compound is the same as in (I). Such an orientation is preferred on steric grounds, since most substituents in the 2-position of the phenyl ring would not be allowed to sit directly over the 1,4-DHP ring. Thus it is not surprising that no crystal structures of 2,6-disubstituted phenyl rings in 4-aryl-1,4-DHP compounds have been reported.

Most of the bond lengths and angles in (I) have normal values. There are small angular distortions about atoms C2 and C10 (Table 1), which result from steric interactions between the methyl substituent at atoms C2 and O1O of the ester substituent at C3 [O10···C9 = 2.829 (2) Å]. The presence of π-electron conjugation keeps the ester group at atom C3 almost coplanar [C2C3—C10O10 = 9.0 (3)°] with the endocyclic double bond and prevents the ester group from rotating into a sterically more amenable orientation. These properties are consistent with those of the many other 2-methyl-3-carboxy-4-aryl-1,4-DHP compounds archived in the Cambridge Structural Database (Allen, 2002).

The oxocyclohexene ring in (I) has a conformation that is approximately half-way between that of a C7 envelope and that of a half-chair twisted around the C6—C7 axis?. This conformation is demonstrated by the puckering parameters [Q = 0.4641 (16) Å, θ = 53.8 (2)° and ϕ2 = 165.5 (2)° for the atom sequence C4a—C5—C6—C7—C8—C8a]. The ϕ2 value, in particular, lies almost exactly half-way between the nearest ideal values that would correspond to an envelope and to a half-chair conformation. Atoms C6 and C7 lie −0.176 (3) and 0.520 (3) Å, respectively, from the plane defined by atoms C4a, C5, C8 and C8a. The maximum deviation of these latter four atoms from their mean plane is 0.0134 (9) Å for both atom C4a and atom C8a. Atom C7 of the ring lies on the same side of the oxocyclohexene ring plane as the 2-chloro-5-nitrophenyl substituent of the adjacent 1,4-DHP ring. It has been found that atom C7 is always the out-of-plane atom in structures involving the 5-oxoquinoline or 1,8-dioxoacridine moiety and that the side of the oxocyclohexene ring to which C7 deviates is, in the majority but not all of these structures, the same as that in (I) (Linden et al., 2002).

An intermolecular hydrogen bond between the amine group and the carbonyl O atom of the oxocyclohexene ring of a neighbouring molecule (Table 2) links the molecules into extended chains that run parallel to the [010] direction and have a graph set motif of C(6) (Bernstein et al., 1995). The same C(6) motif has been observed in the crystal structures of several other 1,4-DHP compounds (Linden et al., 1998, 2002; Şimşek et al., 2000).

Experimental top

For the synthesis of the title compound, equimolar amounts of 2-chloro-5-nitrobenzaldehyde, 5,5-dimethyl-1,3-cyclohexanedione and methyl acetoacetate plus ammonia (1 ml) were refluxed in methanol for 4 h. The solution was then poured into water and the precipitate that formed was filtered, dried and recrystallized from ethanol (m.p. 513 K).

Refinement top

The position of the amine H atom was determined from a difference Fourier map and refined freely along with its isotropic displacement parameter. The methyl H atoms were constrained to an ideal geometry [C—H = 0.98 Å, with Uiso(H) = 1.5Ueq(C)] but were allowed to rotate freely about the C—C bonds. All remaining H atoms were placed in idealized positions (C—H = 0.95–1.00 Å) and constrained to ride on their parent atoms [Uiso(H) = 1.2Ueq(C)]. Three low-angle reflections were omitted from the final cycles of refinement because their observed intensities were much lower than the calculated values as a result of being partially obscured by the beam stop.

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2004).

Figures top
[Figure 1] Fig. 1. View of the molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are represented by circles of arbitrary size.
Methyl 4-(2-chloro-5-nitrophenyl)-2,7,7-trimethyl-5-oxo- 1,4,5,6,7,8-hexahydroquinoline-3-carboxylate top
Crystal data top
C20H21ClN2O5Dx = 1.426 Mg m3
Mr = 404.85Melting point: 513 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 33903 reflections
a = 14.8737 (2) Åθ = 2.0–30.0°
b = 14.3865 (2) ŵ = 0.24 mm1
c = 17.6287 (3) ÅT = 160 K
V = 3772.20 (10) Å3Prism, yellow
Z = 80.27 × 0.22 × 0.10 mm
F(000) = 1696
Data collection top
Nonius KappaCCD area-detector
diffractometer
5520 independent reflections
Radiation source: Nonius FR590 sealed tube generator4106 reflections with I > 2σ(I)
Horizontally mounted graphite crystal monochromatorRint = 0.069
Detector resolution: 9 pixels mm-1θmax = 30.0°, θmin = 2.3°
ϕ and ω scans with κ offsetsh = 2020
Absorption correction: multi-scan
(Blessing, 1995)
k = 2020
Tmin = 0.845, Tmax = 0.981l = 2424
68164 measured reflections
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)] = 0.047Hydrogen site location: geom & difmap
wR(F2) = 0.129H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0606P)2 + 1.849P]
where P = (Fo2 + 2Fc2)/3
5517 reflections(Δ/σ)max = 0.001
261 parametersΔρmax = 0.47 e Å3
0 restraintsΔρmin = 0.44 e Å3
Crystal data top
C20H21ClN2O5V = 3772.20 (10) Å3
Mr = 404.85Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 14.8737 (2) ŵ = 0.24 mm1
b = 14.3865 (2) ÅT = 160 K
c = 17.6287 (3) Å0.27 × 0.22 × 0.10 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
5520 independent reflections
Absorption correction: multi-scan
(Blessing, 1995)
4106 reflections with I > 2σ(I)
Tmin = 0.845, Tmax = 0.981Rint = 0.069
68164 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.129H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.47 e Å3
5517 reflectionsΔρmin = 0.44 e Å3
261 parameters
Special details top

Experimental. Solvent used: ? Cooling Device: Oxford Cryosystems Cryostream 700 Crystal mount: glued on a glass fibre Mosaicity (°.): 0.422 (1) Frames collected: 250 Seconds exposure per frame: 57 Degrees rotation per frame: 1.9 Crystal-Detector distance (mm): 30.0

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 3.1212 (0.0088) x − 3.4512 (0.0149) y + 16.7093 (0.0054) z = 7.1371 (0.0108)

* −0.0002 (0.0007) C2 * 0.0002 (0.0007) C3 * −0.0002 (0.0007) C4A * 0.0002 (0.0007) C8A 0.1153 (0.0022) N1 0.2834 (0.0023) C4

Rms deviation of fitted atoms = 0.0002

− 6.4120 (0.0104) x − 2.3924 (0.0089) y + 15.6340 (0.0064) z = 4.2156 (0.0113)

* −0.0067 (0.0010) C4A * 0.0521 (0.0011) C5 * −0.0480 (0.0008) C6 * 0.0450 (0.0008) C8 * −0.0424 (0.0010) C8A 0.6355 (0.0022) C7

Rms deviation of fitted atoms = 0.0422

− 5.6352 (0.0160) x − 2.6680 (0.0096) y + 15.9836 (0.0077) z = 4.9399 (0.0157)

* 0.0134 (0.0009) C4A * −0.0062 (0.0004) C5 * 0.0062 (0.0004) C8 * −0.0134 (0.0009) C8A −0.1759 (0.0029) C6 0.5203 (0.0029) C7

Rms deviation of fitted atoms = 0.0105

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
Cl0.86064 (3)0.45386 (3)0.73696 (2)0.03563 (12)
O10.76180 (11)0.10876 (10)0.96762 (8)0.0483 (4)
O20.79307 (12)0.03035 (9)0.86719 (8)0.0495 (4)
O50.69801 (8)0.37333 (7)0.62302 (7)0.0298 (3)
O101.08445 (8)0.18436 (10)0.63816 (8)0.0396 (3)
O111.01268 (8)0.31017 (9)0.68278 (7)0.0325 (3)
N10.81950 (9)0.07300 (9)0.60219 (8)0.0272 (3)
H10.8093 (13)0.0161 (15)0.5944 (12)0.037 (5)*
N170.78331 (10)0.10370 (10)0.90091 (8)0.0312 (3)
C20.90663 (10)0.10184 (11)0.61750 (9)0.0262 (3)
C30.92247 (10)0.19081 (11)0.63887 (8)0.0241 (3)
C40.84547 (9)0.25778 (10)0.65526 (8)0.0218 (3)
H40.86180.32030.63470.026*
C4a0.76084 (10)0.22472 (10)0.61565 (8)0.0213 (3)
C50.69048 (10)0.29238 (10)0.60091 (8)0.0233 (3)
C60.60964 (10)0.26052 (11)0.55648 (9)0.0264 (3)
H610.62280.26630.50160.032*
H620.55830.30190.56810.032*
C70.58250 (10)0.15992 (10)0.57367 (9)0.0246 (3)
C80.66485 (10)0.09724 (11)0.56008 (9)0.0251 (3)
H810.65250.03490.58140.030*
H820.67410.09000.50480.030*
C8a0.74962 (10)0.13467 (10)0.59499 (8)0.0226 (3)
C90.97600 (12)0.02700 (13)0.60833 (11)0.0368 (4)
H911.01320.04050.56380.055*
H920.94600.03310.60150.055*
H931.01400.02470.65370.055*
C101.01475 (10)0.22436 (12)0.65205 (9)0.0271 (3)
C121.09847 (12)0.35288 (15)0.69777 (12)0.0410 (4)
H1211.13370.31270.73140.062*
H1221.08910.41330.72220.062*
H1231.13090.36170.64990.062*
C130.83110 (9)0.26645 (10)0.74086 (8)0.0216 (3)
C140.83889 (10)0.34937 (11)0.78190 (9)0.0253 (3)
C150.82978 (11)0.35227 (11)0.86067 (9)0.0283 (3)
H150.83690.40950.88690.034*
C160.81042 (10)0.27194 (11)0.90042 (9)0.0275 (3)
H160.80350.27280.95400.033*
C170.80153 (10)0.19042 (11)0.85988 (9)0.0246 (3)
C180.81150 (10)0.18610 (10)0.78212 (8)0.0233 (3)
H180.80500.12830.75660.028*
C190.55020 (11)0.15250 (12)0.65593 (9)0.0307 (3)
H1910.60060.16490.69030.046*
H1920.52700.08980.66520.046*
H1930.50240.19810.66490.046*
C200.50592 (11)0.13148 (12)0.52036 (10)0.0328 (4)
H2010.45710.17700.52390.049*
H2020.48350.07000.53500.049*
H2030.52830.12930.46810.049*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl0.0516 (3)0.02194 (19)0.0333 (2)0.00842 (17)0.00422 (18)0.00209 (15)
O10.0717 (10)0.0394 (7)0.0339 (7)0.0100 (7)0.0198 (7)0.0106 (6)
O20.0853 (11)0.0250 (7)0.0383 (7)0.0054 (7)0.0074 (7)0.0023 (5)
O50.0363 (6)0.0193 (5)0.0339 (6)0.0010 (4)0.0037 (5)0.0022 (5)
O100.0251 (6)0.0465 (8)0.0471 (8)0.0001 (5)0.0030 (5)0.0035 (6)
O110.0254 (6)0.0351 (7)0.0370 (6)0.0065 (5)0.0005 (5)0.0029 (5)
N10.0270 (7)0.0181 (6)0.0366 (7)0.0005 (5)0.0009 (5)0.0009 (6)
N170.0358 (7)0.0276 (7)0.0301 (7)0.0017 (6)0.0039 (6)0.0057 (6)
C20.0259 (7)0.0263 (7)0.0264 (7)0.0026 (6)0.0031 (6)0.0033 (6)
C30.0239 (7)0.0258 (7)0.0227 (7)0.0001 (6)0.0019 (5)0.0031 (6)
C40.0235 (7)0.0202 (7)0.0218 (7)0.0028 (5)0.0006 (5)0.0020 (5)
C4a0.0239 (7)0.0197 (7)0.0202 (6)0.0004 (5)0.0006 (5)0.0013 (5)
C50.0281 (7)0.0198 (7)0.0219 (7)0.0002 (5)0.0008 (6)0.0014 (5)
C60.0282 (7)0.0219 (7)0.0291 (8)0.0009 (6)0.0043 (6)0.0000 (6)
C70.0250 (7)0.0215 (7)0.0273 (7)0.0002 (5)0.0001 (6)0.0032 (6)
C80.0279 (7)0.0208 (7)0.0266 (7)0.0018 (6)0.0005 (6)0.0038 (6)
C8a0.0256 (7)0.0201 (7)0.0221 (7)0.0004 (5)0.0018 (6)0.0018 (5)
C90.0321 (9)0.0311 (9)0.0470 (10)0.0072 (7)0.0018 (7)0.0025 (8)
C100.0259 (7)0.0333 (8)0.0219 (7)0.0025 (6)0.0015 (6)0.0050 (6)
C120.0299 (9)0.0466 (11)0.0465 (11)0.0128 (8)0.0033 (8)0.0041 (9)
C130.0207 (6)0.0209 (7)0.0233 (7)0.0002 (5)0.0006 (5)0.0015 (6)
C140.0271 (7)0.0210 (7)0.0278 (7)0.0013 (6)0.0025 (6)0.0015 (6)
C150.0324 (8)0.0242 (7)0.0282 (8)0.0024 (6)0.0033 (6)0.0034 (6)
C160.0283 (8)0.0299 (8)0.0244 (7)0.0052 (6)0.0013 (6)0.0001 (6)
C170.0232 (7)0.0242 (7)0.0265 (7)0.0028 (5)0.0031 (6)0.0060 (6)
C180.0235 (7)0.0208 (7)0.0257 (7)0.0008 (5)0.0017 (5)0.0008 (6)
C190.0295 (8)0.0309 (8)0.0318 (8)0.0003 (6)0.0038 (6)0.0002 (7)
C200.0307 (8)0.0319 (9)0.0359 (9)0.0018 (7)0.0051 (7)0.0047 (7)
Geometric parameters (Å, º) top
Cl—C141.7298 (16)C7—C81.540 (2)
O1—N171.2208 (18)C8—C8a1.503 (2)
O2—N171.2199 (19)C8—H810.9900
O5—C51.2331 (18)C8—H820.9900
O10—C101.211 (2)C9—H910.9800
O11—C101.349 (2)C9—H920.9800
O11—C121.441 (2)C9—H930.9800
N1—C8a1.372 (2)C12—H1210.9800
N1—C21.387 (2)C12—H1220.9800
N1—H10.84 (2)C12—H1230.9800
N17—C171.467 (2)C13—C181.397 (2)
C2—C31.355 (2)C13—C141.400 (2)
C2—C91.500 (2)C14—C151.396 (2)
C3—C101.473 (2)C15—C161.382 (2)
C3—C41.524 (2)C15—H150.9500
C4—C4a1.516 (2)C16—C171.380 (2)
C4—C131.529 (2)C16—H160.9500
C4—H41.0000C17—C181.380 (2)
C4a—C8a1.356 (2)C18—H180.9500
C4a—C51.453 (2)C19—H1910.9800
C5—C61.506 (2)C19—H1920.9800
C6—C71.533 (2)C19—H1930.9800
C6—H610.9900C20—H2010.9800
C6—H620.9900C20—H2020.9800
C7—C191.531 (2)C20—H2030.9800
C7—C201.532 (2)
C10—O11—C12116.36 (14)C2—C9—H91109.5
C2—N1—C8a122.15 (14)C2—C9—H92109.5
C8a—N1—H1118.4 (14)H91—C9—H92109.5
C2—N1—H1119.4 (14)C2—C9—H93109.5
O2—N17—O1123.52 (14)H91—C9—H93109.5
O2—N17—C17118.25 (13)H92—C9—H93109.5
O1—N17—C17118.20 (14)O10—C10—O11122.40 (15)
N1—C2—C3119.94 (14)O10—C10—C3127.60 (16)
C3—C2—C9126.05 (15)O11—C10—C3110.00 (13)
N1—C2—C9114.01 (14)O11—C12—H121109.5
C2—C3—C10121.02 (14)O11—C12—H122109.5
C2—C3—C4121.28 (13)H121—C12—H122109.5
C10—C3—C4117.58 (13)O11—C12—H123109.5
C4a—C4—C3109.77 (12)H121—C12—H123109.5
C4a—C4—C13111.35 (12)H122—C12—H123109.5
C3—C4—C13110.10 (12)C18—C13—C14116.97 (13)
C4a—C4—H4108.5C18—C13—C4118.40 (13)
C3—C4—H4108.5C14—C13—C4124.60 (13)
C13—C4—H4108.5C15—C14—C13122.11 (14)
C8a—C4a—C5120.23 (13)C15—C14—Cl116.60 (12)
C4—C4a—C8a121.71 (13)C13—C14—Cl121.29 (12)
C5—C4a—C4118.05 (12)C16—C15—C14119.98 (15)
O5—C5—C4a120.72 (14)C16—C15—H15120.0
O5—C5—C6121.61 (13)C14—C15—H15120.0
C4a—C5—C6117.65 (13)C17—C16—C15117.92 (14)
C5—C6—C7113.25 (13)C17—C16—H16121.0
C5—C6—H61108.9C15—C16—H16121.0
C7—C6—H61108.9C16—C17—C18122.85 (14)
C5—C6—H62108.9C16—C17—N17119.02 (14)
C7—C6—H62108.9C18—C17—N17118.11 (14)
H61—C6—H62107.7C17—C18—C13120.16 (14)
C19—C7—C20109.21 (13)C17—C18—H18119.9
C19—C7—C6109.61 (13)C13—C18—H18119.9
C20—C7—C6109.06 (13)C7—C19—H191109.5
C19—C7—C8110.86 (13)C7—C19—H192109.5
C20—C7—C8109.85 (13)H191—C19—H192109.5
C6—C7—C8108.23 (12)C7—C19—H193109.5
C8a—C8—C7113.19 (12)H191—C19—H193109.5
C8a—C8—H81108.9H192—C19—H193109.5
C7—C8—H81108.9C7—C20—H201109.5
C8a—C8—H82108.9C7—C20—H202109.5
C7—C8—H82108.9H201—C20—H202109.5
H81—C8—H82107.8C7—C20—H203109.5
N1—C8a—C4a119.97 (14)H201—C20—H203109.5
C4a—C8a—C8123.75 (13)H202—C20—H203109.5
N1—C8a—C8116.21 (13)
C8a—N1—C2—C311.5 (2)C2—N1—C8a—C8165.57 (14)
C8a—N1—C2—C9168.72 (15)C7—C8—C8a—C4a19.1 (2)
N1—C2—C3—C10177.16 (14)C7—C8—C8a—N1163.99 (13)
C9—C2—C3—C103.1 (2)C12—O11—C10—O100.6 (2)
N1—C2—C3—C47.0 (2)C12—O11—C10—C3179.00 (14)
C9—C2—C3—C4172.72 (15)C2—C3—C10—O109.0 (3)
C2—C3—C4—C4a22.25 (19)C4—C3—C10—O10175.03 (16)
C10—C3—C4—C4a161.78 (13)C2—C3—C10—O11171.43 (14)
C2—C3—C4—C13100.67 (16)C4—C3—C10—O114.55 (18)
C10—C3—C4—C1375.29 (16)C4a—C4—C13—C1863.44 (17)
C3—C4—C4a—C8a22.41 (19)C3—C4—C13—C1858.55 (17)
C13—C4—C4a—C8a99.77 (16)C4a—C4—C13—C14118.63 (15)
C3—C4—C4a—C5158.34 (13)C3—C4—C13—C14119.38 (15)
C13—C4—C4a—C579.48 (16)C18—C13—C14—C151.5 (2)
C8a—C4a—C5—O5176.16 (14)C4—C13—C14—C15176.46 (14)
C4—C4a—C5—O53.1 (2)C18—C13—C14—Cl178.62 (11)
C8a—C4a—C5—C65.1 (2)C4—C13—C14—Cl3.4 (2)
C4—C4a—C5—C6175.60 (13)C13—C14—C15—C161.5 (2)
O5—C5—C6—C7145.68 (14)Cl—C14—C15—C16178.60 (12)
C4a—C5—C6—C735.62 (19)C14—C15—C16—C170.6 (2)
C5—C6—C7—C1965.91 (17)C15—C16—C17—C180.3 (2)
C5—C6—C7—C20174.58 (13)C15—C16—C17—N17178.42 (14)
C5—C6—C7—C855.11 (17)O2—N17—C17—C16165.79 (16)
C19—C7—C8—C8a73.79 (16)O1—N17—C17—C1612.1 (2)
C20—C7—C8—C8a165.43 (13)O2—N17—C17—C1812.4 (2)
C6—C7—C8—C8a46.45 (17)O1—N17—C17—C18169.70 (15)
C5—C4a—C8a—N1173.59 (13)C16—C17—C18—C130.3 (2)
C4—C4a—C8a—N17.2 (2)N17—C17—C18—C13178.42 (13)
C5—C4a—C8a—C83.2 (2)C14—C13—C18—C170.6 (2)
C4—C4a—C8a—C8176.02 (13)C4—C13—C18—C17177.47 (13)
C2—N1—C8a—C4a11.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O5i0.84 (2)2.12 (2)2.9076 (18)156 (2)
Symmetry code: (i) x+3/2, y1/2, z.

Experimental details

Crystal data
Chemical formulaC20H21ClN2O5
Mr404.85
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)160
a, b, c (Å)14.8737 (2), 14.3865 (2), 17.6287 (3)
V3)3772.20 (10)
Z8
Radiation typeMo Kα
µ (mm1)0.24
Crystal size (mm)0.27 × 0.22 × 0.10
Data collection
DiffractometerNonius KappaCCD area-detector
diffractometer
Absorption correctionMulti-scan
(Blessing, 1995)
Tmin, Tmax0.845, 0.981
No. of measured, independent and
observed [I > 2σ(I)] reflections
68164, 5520, 4106
Rint0.069
(sin θ/λ)max1)0.704
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.129, 1.03
No. of reflections5517
No. of parameters261
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.47, 0.44

Computer programs: COLLECT (Nonius, 2000), DENZO-SMN (Otwinowski & Minor, 1997), DENZO-SMN and SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 1997), ORTEPII (Johnson, 1976), SHELXL97 and PLATON (Spek, 2004).

Selected geometric parameters (Å, º) top
O10—C101.211 (2)C3—C101.473 (2)
O11—C101.349 (2)C3—C41.524 (2)
N1—C8a1.372 (2)C4—C4a1.516 (2)
N1—C21.387 (2)C4a—C8a1.356 (2)
C2—C31.355 (2)
C2—N1—C8a122.15 (14)C4—C4a—C8a121.71 (13)
N1—C2—C3119.94 (14)N1—C8a—C4a119.97 (14)
C3—C2—C9126.05 (15)O10—C10—O11122.40 (15)
N1—C2—C9114.01 (14)O10—C10—C3127.60 (16)
C2—C3—C4121.28 (13)O11—C10—C3110.00 (13)
C4a—C4—C3109.77 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O5i0.84 (2)2.12 (2)2.9076 (18)156 (2)
Symmetry code: (i) x+3/2, y1/2, z.
 

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