Buy article online - an online subscription or single-article purchase is required to access this article.
The title compound [systematic name: 9,10-dimethoxy-2,3-methylenedioxy-5,6-dihydrodibenzo[
a,
g]quinolizinium formate–succinic acid (1/1)], C
20H
18NO
4+·CHO
2−·C
4H
6O
4, contains centrosymmetric pairs of almost planar berberine cations, and hydrogen-bonded (C
4H
6O
4HCOO
−)
2 rings of succinic acid with formate anions, bonded by O—H
O hydrogen bonds with O
O distances of 2.4886 (15) and 2.5652 (16) Å. Pairs of cations and molecules of succinic acid are connected by non-conventional weak C—H
O hydrogen bonds, with C
O distances of 3.082 (2) and 3.178 (2) Å.
Supporting information
CCDC reference: 224667
The title compound was obtained by decomposition of 8-(imidazol-1-yl)-7,8-dihydroberberine and crystallization from undistilled tetrahydrofuran.
All H atoms were located in a difference electron-density map. H atoms in methyl, CH2 and O—H groups were fixed in their theoretical geometrical positions with Ueq driven by the corresponding C or O atoms. Other H atoms were refined freely.
Data collection: CrysAlis CCD (Oxford Diffraction, 2002); cell refinement: CrysAlis RED (Oxford Diffraction, 2002); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Johnson & Burnett, 1996); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1995).
9,10-dimethoxy-2,3-methylendioxy-5,6-dihydrodibenzo[a,g]quinolizinium formate-succinic acid (1/1)
top
Crystal data top
C20H18NO4+·CHO2−·C4H6O4 | Z = 2 |
Mr = 499.46 | F(000) = 524 |
Triclinic, P1 | Dx = 1.491 Mg m−3 |
Hall symbol: -P 1 | Melting point: 478(2) - decomposition K |
a = 7.9973 (8) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 12.4449 (9) Å | Cell parameters from 5207 reflections |
c = 12.6115 (12) Å | θ = 3.0–28.4° |
α = 63.753 (8)° | µ = 0.12 mm−1 |
β = 81.410 (8)° | T = 100 K |
γ = 84.866 (7)° | Prism, yellow |
V = 1112.74 (19) Å3 | 0.6 × 0.5 × 0.4 mm |
Data collection top
Kuma KM4 with CCD area-detector diffractometer | 3443 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.027 |
Enhance (Oxford Diffraction) monochromator | θmax = 25.0°, θmin = 3.1° |
Detector resolution: 16.3 pixels mm-1 | h = −8→9 |
rotation method, ω scans | k = −14→14 |
5978 measured reflections | l = −14→13 |
3802 independent reflections | |
Refinement top
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.034 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.115 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.075P)2 + 0.5P] where P = (Fo2 + 2Fc2)/3 |
3802 reflections | (Δ/σ)max < 0.001 |
355 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.34 e Å−3 |
Crystal data top
C20H18NO4+·CHO2−·C4H6O4 | γ = 84.866 (7)° |
Mr = 499.46 | V = 1112.74 (19) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.9973 (8) Å | Mo Kα radiation |
b = 12.4449 (9) Å | µ = 0.12 mm−1 |
c = 12.6115 (12) Å | T = 100 K |
α = 63.753 (8)° | 0.6 × 0.5 × 0.4 mm |
β = 81.410 (8)° | |
Data collection top
Kuma KM4 with CCD area-detector diffractometer | 3443 reflections with I > 2σ(I) |
5978 measured reflections | Rint = 0.027 |
3802 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.034 | 0 restraints |
wR(F2) = 0.115 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.28 e Å−3 |
3802 reflections | Δρmin = −0.34 e Å−3 |
355 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 | x | y | z | Uiso*/Ueq | |
O1 | 0.18951 (13) | 0.21279 (9) | −0.50582 (9) | 0.0175 (2) | |
O2 | 0.24748 (13) | 0.40990 (10) | −0.55428 (9) | 0.0189 (3) | |
O3 | −0.41402 (13) | −0.01022 (9) | 0.31041 (9) | 0.0166 (2) | |
O4 | −0.53375 (13) | −0.22912 (9) | 0.36453 (9) | 0.0173 (2) | |
O5 | 0.33656 (14) | −0.43595 (10) | −0.28123 (9) | 0.0199 (3) | |
H5 | 0.3869 | −0.4769 | −0.2214 | 0.030* | |
O6 | 0.32745 (14) | −0.29638 (10) | −0.21295 (10) | 0.0236 (3) | |
O7 | −0.07654 (15) | −0.13676 (10) | −0.19570 (10) | 0.0238 (3) | |
O8 | −0.08017 (14) | −0.30820 (10) | −0.21285 (10) | 0.0214 (3) | |
H8 | −0.1377 | −0.3310 | −0.1456 | 0.032* | |
O9 | −0.23840 (14) | −0.40122 (11) | −0.00933 (10) | 0.0262 (3) | |
O10 | −0.49024 (14) | −0.43117 (10) | 0.10049 (10) | 0.0219 (3) | |
C1 | 0.03082 (18) | 0.16941 (13) | −0.30765 (13) | 0.0143 (3) | |
C2 | 0.12019 (18) | 0.24121 (14) | −0.41355 (13) | 0.0144 (3) | |
C3 | 0.15317 (18) | 0.36009 (14) | −0.44406 (13) | 0.0152 (3) | |
C4 | 0.09293 (18) | 0.41347 (13) | −0.36999 (13) | 0.0158 (3) | |
C4a | −0.00292 (18) | 0.34328 (13) | −0.26135 (13) | 0.0143 (3) | |
C5 | −0.08275 (19) | 0.39723 (13) | −0.17891 (13) | 0.0171 (3) | |
H5A | −0.2001 | 0.4246 | −0.1958 | 0.020* | |
H5B | −0.0184 | 0.4678 | −0.1934 | 0.020* | |
C6 | −0.08438 (19) | 0.30612 (13) | −0.04948 (13) | 0.0163 (3) | |
H6A | 0.0330 | 0.2889 | −0.0291 | 0.020* | |
H6B | −0.1490 | 0.3400 | 0.0026 | 0.020* | |
N7 | −0.16287 (15) | 0.19200 (11) | −0.02755 (11) | 0.0127 (3) | |
C8 | −0.24933 (18) | 0.12948 (13) | 0.07928 (13) | 0.0135 (3) | |
C8a | −0.31304 (17) | 0.01648 (13) | 0.11031 (13) | 0.0129 (3) | |
C9 | −0.40015 (17) | −0.05271 (13) | 0.22521 (13) | 0.0133 (3) | |
C10 | −0.45689 (17) | −0.16509 (13) | 0.25152 (13) | 0.0139 (3) | |
C11 | −0.43073 (18) | −0.20956 (13) | 0.16379 (13) | 0.0154 (3) | |
C12 | −0.34670 (18) | −0.14344 (13) | 0.05248 (13) | 0.0149 (3) | |
C12a | −0.28509 (18) | −0.02976 (13) | 0.02333 (13) | 0.0134 (3) | |
C13 | −0.19578 (18) | 0.04069 (13) | −0.08833 (13) | 0.0136 (3) | |
C13a | −0.13174 (17) | 0.14971 (13) | −0.11479 (13) | 0.0129 (3) | |
C13b | −0.03178 (17) | 0.22265 (13) | −0.22946 (13) | 0.0129 (3) | |
C14 | 0.29902 (19) | 0.31021 (14) | −0.58283 (13) | 0.0179 (3) | |
H14A | 0.2883 | 0.3329 | −0.6673 | 0.021* | |
H14B | 0.4184 | 0.2864 | −0.5695 | 0.021* | |
C15 | −0.5788 (2) | 0.03888 (16) | 0.33123 (15) | 0.0249 (4) | |
H15A | −0.6021 | 0.1110 | 0.2595 | 0.037* | |
H15B | −0.5819 | 0.0596 | 0.3980 | 0.037* | |
H15C | −0.6647 | −0.0206 | 0.3504 | 0.037* | |
C16 | −0.58618 (19) | −0.34835 (14) | 0.39500 (13) | 0.0179 (3) | |
H16A | −0.6791 | −0.3433 | 0.3502 | 0.027* | |
H16B | −0.6244 | −0.3889 | 0.4806 | 0.027* | |
H16C | −0.4906 | −0.3938 | 0.3749 | 0.027* | |
C17 | 0.29031 (18) | −0.33065 (13) | −0.28304 (13) | 0.0158 (3) | |
C18 | 0.19097 (19) | −0.25215 (14) | −0.38521 (13) | 0.0189 (3) | |
H18A | 0.1122 | −0.3023 | −0.3964 | 0.023* | |
H18B | 0.2701 | −0.2162 | −0.4594 | 0.023* | |
C19 | 0.09052 (19) | −0.15243 (14) | −0.36290 (13) | 0.0184 (3) | |
H19A | 0.1704 | −0.0979 | −0.3596 | 0.022* | |
H19B | 0.0253 | −0.1053 | −0.4306 | 0.022* | |
C20 | −0.03045 (18) | −0.19915 (13) | −0.24824 (13) | 0.0160 (3) | |
C21 | −0.3967 (2) | −0.39363 (14) | 0.00260 (14) | 0.0193 (3) | |
H1 | 0.016 (2) | 0.0846 (18) | −0.2852 (16) | 0.019 (4)* | |
H4 | 0.117 (2) | 0.4984 (18) | −0.3905 (16) | 0.021 (4)* | |
H8A | −0.258 (2) | 0.1652 (16) | 0.1321 (16) | 0.018 (4)* | |
H11 | −0.473 (2) | −0.2885 (17) | 0.1835 (15) | 0.017 (4)* | |
H12 | −0.330 (2) | −0.1755 (17) | −0.0033 (17) | 0.024 (5)* | |
H13 | −0.179 (2) | 0.0122 (17) | −0.1453 (17) | 0.024 (5)* | |
H21 | −0.446 (2) | −0.3555 (17) | −0.0681 (18) | 0.025 (5)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0190 (5) | 0.0195 (6) | 0.0142 (5) | −0.0040 (4) | 0.0029 (4) | −0.0084 (4) |
O2 | 0.0213 (6) | 0.0183 (6) | 0.0142 (5) | −0.0050 (4) | 0.0041 (4) | −0.0056 (4) |
O3 | 0.0182 (5) | 0.0192 (6) | 0.0152 (5) | −0.0002 (4) | −0.0018 (4) | −0.0102 (4) |
O4 | 0.0220 (6) | 0.0144 (5) | 0.0139 (5) | −0.0047 (4) | 0.0018 (4) | −0.0050 (4) |
O5 | 0.0256 (6) | 0.0169 (6) | 0.0183 (5) | 0.0002 (4) | −0.0030 (4) | −0.0087 (4) |
O6 | 0.0274 (6) | 0.0235 (6) | 0.0251 (6) | 0.0034 (5) | −0.0081 (5) | −0.0147 (5) |
O7 | 0.0290 (6) | 0.0206 (6) | 0.0250 (6) | 0.0037 (5) | −0.0016 (5) | −0.0141 (5) |
O8 | 0.0261 (6) | 0.0205 (6) | 0.0188 (6) | −0.0076 (4) | 0.0033 (5) | −0.0103 (5) |
O9 | 0.0222 (6) | 0.0329 (7) | 0.0210 (6) | −0.0084 (5) | −0.0010 (5) | −0.0085 (5) |
O10 | 0.0206 (6) | 0.0206 (6) | 0.0251 (6) | −0.0012 (4) | 0.0000 (5) | −0.0112 (5) |
C1 | 0.0136 (7) | 0.0137 (8) | 0.0152 (7) | −0.0004 (5) | −0.0028 (6) | −0.0055 (6) |
C2 | 0.0121 (7) | 0.0193 (8) | 0.0138 (7) | 0.0015 (5) | −0.0034 (6) | −0.0087 (6) |
C3 | 0.0125 (7) | 0.0179 (8) | 0.0126 (7) | −0.0009 (5) | −0.0029 (5) | −0.0037 (6) |
C4 | 0.0158 (7) | 0.0129 (8) | 0.0172 (7) | −0.0017 (6) | −0.0028 (6) | −0.0048 (6) |
C4a | 0.0120 (7) | 0.0151 (7) | 0.0156 (7) | 0.0005 (5) | −0.0043 (6) | −0.0059 (6) |
C5 | 0.0191 (7) | 0.0130 (7) | 0.0183 (8) | −0.0029 (6) | 0.0008 (6) | −0.0065 (6) |
C6 | 0.0183 (7) | 0.0146 (7) | 0.0178 (7) | −0.0048 (6) | −0.0005 (6) | −0.0084 (6) |
N7 | 0.0126 (6) | 0.0123 (6) | 0.0135 (6) | −0.0005 (5) | −0.0020 (5) | −0.0057 (5) |
C8 | 0.0125 (7) | 0.0154 (7) | 0.0136 (7) | 0.0013 (5) | −0.0032 (5) | −0.0071 (6) |
C8a | 0.0105 (7) | 0.0136 (7) | 0.0147 (7) | 0.0016 (5) | −0.0036 (5) | −0.0059 (6) |
C9 | 0.0117 (7) | 0.0158 (7) | 0.0134 (7) | 0.0017 (5) | −0.0035 (5) | −0.0068 (6) |
C10 | 0.0115 (7) | 0.0152 (7) | 0.0128 (7) | 0.0004 (5) | −0.0018 (5) | −0.0040 (6) |
C11 | 0.0156 (7) | 0.0123 (7) | 0.0172 (7) | −0.0005 (6) | −0.0029 (6) | −0.0053 (6) |
C12 | 0.0153 (7) | 0.0154 (7) | 0.0163 (7) | 0.0015 (5) | −0.0032 (6) | −0.0091 (6) |
C12a | 0.0111 (6) | 0.0142 (7) | 0.0151 (7) | 0.0023 (5) | −0.0036 (6) | −0.0066 (6) |
C13 | 0.0129 (7) | 0.0147 (7) | 0.0142 (7) | 0.0018 (5) | −0.0020 (6) | −0.0075 (6) |
C13a | 0.0116 (7) | 0.0137 (7) | 0.0141 (7) | 0.0020 (5) | −0.0036 (6) | −0.0065 (6) |
C13b | 0.0109 (7) | 0.0141 (7) | 0.0137 (7) | 0.0004 (5) | −0.0033 (5) | −0.0055 (6) |
C14 | 0.0183 (7) | 0.0195 (8) | 0.0152 (7) | −0.0047 (6) | 0.0025 (6) | −0.0076 (6) |
C15 | 0.0231 (8) | 0.0268 (9) | 0.0286 (9) | 0.0014 (7) | 0.0021 (7) | −0.0174 (7) |
C16 | 0.0203 (8) | 0.0144 (7) | 0.0168 (7) | −0.0046 (6) | −0.0007 (6) | −0.0046 (6) |
C17 | 0.0135 (7) | 0.0182 (8) | 0.0161 (7) | −0.0039 (6) | 0.0040 (6) | −0.0090 (6) |
C18 | 0.0198 (8) | 0.0217 (8) | 0.0157 (7) | −0.0014 (6) | −0.0001 (6) | −0.0092 (6) |
C19 | 0.0207 (8) | 0.0166 (8) | 0.0174 (7) | −0.0012 (6) | −0.0044 (6) | −0.0062 (6) |
C20 | 0.0145 (7) | 0.0174 (8) | 0.0180 (7) | 0.0033 (6) | −0.0073 (6) | −0.0085 (6) |
C21 | 0.0244 (8) | 0.0144 (8) | 0.0207 (8) | −0.0026 (6) | −0.0050 (7) | −0.0082 (6) |
Geometric parameters (Å, º) top
O1—C2 | 1.3866 (17) | N7—C13a | 1.3987 (19) |
O1—C14 | 1.4404 (18) | C8—C8a | 1.404 (2) |
O2—C3 | 1.3761 (18) | C8—H8A | 0.943 (19) |
O2—C14 | 1.4484 (19) | C8a—C9 | 1.424 (2) |
O3—C9 | 1.3794 (17) | C8a—C12a | 1.430 (2) |
O3—C15 | 1.4402 (19) | C9—C10 | 1.389 (2) |
O4—C10 | 1.3659 (18) | C10—C11 | 1.423 (2) |
O4—C16 | 1.4437 (18) | C11—C12 | 1.377 (2) |
O5—C17 | 1.3206 (19) | C11—H11 | 0.979 (19) |
O5—H5 | 0.8400 | C12—C12a | 1.411 (2) |
O6—C17 | 1.2190 (19) | C12—H12 | 0.94 (2) |
O7—C20 | 1.2283 (19) | C12a—C13 | 1.408 (2) |
O8—C20 | 1.3065 (19) | C13—C13a | 1.374 (2) |
O8—H8 | 0.8400 | C13—H13 | 0.92 (2) |
O9—C21 | 1.252 (2) | C13a—C13b | 1.476 (2) |
O10—C21 | 1.2562 (19) | C14—H14A | 0.9900 |
C1—C2 | 1.366 (2) | C14—H14B | 0.9900 |
C1—C13b | 1.426 (2) | C15—H15A | 0.9800 |
C1—H1 | 0.98 (2) | C15—H15B | 0.9800 |
C2—C3 | 1.394 (2) | C15—H15C | 0.9800 |
C3—C4 | 1.380 (2) | C16—H16A | 0.9800 |
C4—C4a | 1.405 (2) | C16—H16B | 0.9800 |
C4—H4 | 1.000 (19) | C16—H16C | 0.9800 |
C4a—C13b | 1.403 (2) | C17—C18 | 1.516 (2) |
C4a—C5 | 1.511 (2) | C18—C19 | 1.526 (2) |
C5—C6 | 1.520 (2) | C18—H18A | 0.9900 |
C5—H5A | 0.9900 | C18—H18B | 0.9900 |
C5—H5B | 0.9900 | C19—C20 | 1.518 (2) |
C6—N7 | 1.4993 (18) | C19—H19A | 0.9900 |
C6—H6A | 0.9900 | C19—H19B | 0.9900 |
C6—H6B | 0.9900 | C21—H21 | 0.93 (2) |
N7—C8 | 1.3377 (19) | | |
| | | |
C2—O1—C14 | 104.93 (11) | C12a—C12—H12 | 120.5 (12) |
C3—O2—C14 | 105.10 (11) | C13—C12a—C12 | 122.69 (13) |
C9—O3—C15 | 114.34 (11) | C13—C12a—C8a | 118.14 (13) |
C10—O4—C16 | 117.29 (11) | C12—C12a—C8a | 119.17 (13) |
C17—O5—H5 | 109.5 | C13a—C13—C12a | 122.34 (14) |
C20—O8—H8 | 109.5 | C13a—C13—H13 | 119.0 (12) |
C2—C1—C13b | 116.75 (14) | C12a—C13—H13 | 118.7 (12) |
C2—C1—H1 | 121.2 (10) | C13—C13a—N7 | 117.67 (13) |
C13b—C1—H1 | 121.9 (10) | C13—C13a—C13b | 123.20 (13) |
C1—C2—O1 | 128.14 (14) | N7—C13a—C13b | 119.13 (13) |
C1—C2—C3 | 122.41 (13) | C4a—C13b—C1 | 120.98 (13) |
O1—C2—C3 | 109.44 (12) | C4a—C13b—C13a | 120.00 (13) |
O2—C3—C4 | 128.39 (14) | C1—C13b—C13a | 119.00 (13) |
O2—C3—C2 | 109.88 (13) | O1—C14—O2 | 107.09 (11) |
C4—C3—C2 | 121.72 (14) | O1—C14—H14A | 110.3 |
C3—C4—C4a | 117.56 (14) | O2—C14—H14A | 110.3 |
C3—C4—H4 | 122.5 (10) | O1—C14—H14B | 110.3 |
C4a—C4—H4 | 119.9 (10) | O2—C14—H14B | 110.3 |
C13b—C4a—C4 | 120.54 (13) | H14A—C14—H14B | 108.6 |
C13b—C4a—C5 | 118.63 (13) | O3—C15—H15A | 109.5 |
C4—C4a—C5 | 120.79 (13) | O3—C15—H15B | 109.5 |
C4a—C5—C6 | 110.77 (12) | H15A—C15—H15B | 109.5 |
C4a—C5—H5A | 109.5 | O3—C15—H15C | 109.5 |
C6—C5—H5A | 109.5 | H15A—C15—H15C | 109.5 |
C4a—C5—H5B | 109.5 | H15B—C15—H15C | 109.5 |
C6—C5—H5B | 109.5 | O4—C16—H16A | 109.5 |
H5A—C5—H5B | 108.1 | O4—C16—H16B | 109.5 |
N7—C6—C5 | 111.03 (12) | H16A—C16—H16B | 109.5 |
N7—C6—H6A | 109.4 | O4—C16—H16C | 109.5 |
C5—C6—H6A | 109.4 | H16A—C16—H16C | 109.5 |
N7—C6—H6B | 109.4 | H16B—C16—H16C | 109.5 |
C5—C6—H6B | 109.4 | O6—C17—O5 | 124.32 (14) |
H6A—C6—H6B | 108.0 | O6—C17—C18 | 122.24 (14) |
C8—N7—C13a | 122.35 (13) | O5—C17—C18 | 113.40 (12) |
C8—N7—C6 | 118.18 (12) | C17—C18—C19 | 111.96 (12) |
C13a—N7—C6 | 119.26 (12) | C17—C18—H18A | 109.2 |
N7—C8—C8a | 121.46 (13) | C19—C18—H18A | 109.2 |
N7—C8—H8A | 114.9 (11) | C17—C18—H18B | 109.2 |
C8a—C8—H8A | 123.6 (11) | C19—C18—H18B | 109.2 |
C8—C8a—C9 | 121.94 (13) | H18A—C18—H18B | 107.9 |
C8—C8a—C12a | 118.01 (13) | C20—C19—C18 | 112.97 (12) |
C9—C8a—C12a | 120.03 (13) | C20—C19—H19A | 109.0 |
O3—C9—C10 | 121.65 (13) | C18—C19—H19A | 109.0 |
O3—C9—C8a | 118.87 (13) | C20—C19—H19B | 109.0 |
C10—C9—C8a | 119.28 (13) | C18—C19—H19B | 109.0 |
O4—C10—C9 | 116.61 (13) | H19A—C19—H19B | 107.8 |
O4—C10—C11 | 123.10 (13) | O7—C20—O8 | 124.23 (14) |
C9—C10—C11 | 120.27 (13) | O7—C20—C19 | 121.21 (14) |
C12—C11—C10 | 120.91 (14) | O8—C20—C19 | 114.56 (13) |
C12—C11—H11 | 119.9 (10) | O9—C21—O10 | 125.13 (15) |
C10—C11—H11 | 119.2 (10) | O9—C21—H21 | 115.6 (12) |
C11—C12—C12a | 120.32 (14) | O10—C21—H21 | 119.3 (12) |
C11—C12—H12 | 119.1 (12) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5···O10i | 0.84 | 1.73 | 2.5652 (16) | 176 |
O8—H8···O9 | 0.84 | 1.66 | 2.4886 (15) | 169 |
C13—H13···O7 | 0.92 (2) | 2.26 (2) | 3.0825 (18) | 147.9 (16) |
C8—H8A···O6ii | 0.943 (19) | 2.270 (19) | 3.1775 (19) | 161.3 (15) |
Symmetry codes: (i) −x, −y−1, −z; (ii) −x, −y, −z. |
Experimental details
Crystal data |
Chemical formula | C20H18NO4+·CHO2−·C4H6O4 |
Mr | 499.46 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 100 |
a, b, c (Å) | 7.9973 (8), 12.4449 (9), 12.6115 (12) |
α, β, γ (°) | 63.753 (8), 81.410 (8), 84.866 (7) |
V (Å3) | 1112.74 (19) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.12 |
Crystal size (mm) | 0.6 × 0.5 × 0.4 |
|
Data collection |
Diffractometer | Kuma KM4 with CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5978, 3802, 3443 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.595 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.034, 0.115, 1.03 |
No. of reflections | 3802 |
No. of parameters | 355 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.28, −0.34 |
Selected geometric parameters (Å, º) topO1—C2 | 1.3866 (17) | C4a—C5 | 1.511 (2) |
O1—C14 | 1.4404 (18) | C5—C6 | 1.520 (2) |
O2—C3 | 1.3761 (18) | C6—N7 | 1.4993 (18) |
O2—C14 | 1.4484 (19) | N7—C8 | 1.3377 (19) |
O3—C9 | 1.3794 (17) | N7—C13a | 1.3987 (19) |
O3—C15 | 1.4402 (19) | C8—C8a | 1.404 (2) |
O4—C10 | 1.3659 (18) | C8a—C12a | 1.430 (2) |
O4—C16 | 1.4437 (18) | C12a—C13 | 1.408 (2) |
C4a—C13b | 1.403 (2) | C13a—C13b | 1.476 (2) |
| | | |
C9—O3—C15 | 114.34 (11) | O3—C9—C10 | 121.65 (13) |
C10—O4—C16 | 117.29 (11) | O3—C9—C8a | 118.87 (13) |
C8—N7—C13a | 122.35 (13) | O4—C10—C9 | 116.61 (13) |
C8—N7—C6 | 118.18 (12) | O4—C10—C11 | 123.10 (13) |
C13a—N7—C6 | 119.26 (12) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5···O10i | 0.84 | 1.73 | 2.5652 (16) | 176 |
O8—H8···O9 | 0.84 | 1.66 | 2.4886 (15) | 169 |
C13—H13···O7 | 0.92 (2) | 2.26 (2) | 3.0825 (18) | 147.9 (16) |
C8—H8A···O6ii | 0.943 (19) | 2.270 (19) | 3.1775 (19) | 161.3 (15) |
Symmetry codes: (i) −x, −y−1, −z; (ii) −x, −y, −z. |
Subscribe to Acta Crystallographica Section C: Structural Chemistry
The full text of this article is available to subscribers to the journal.
If you have already registered and are using a computer listed in your registration details, please email
support@iucr.org for assistance.
Berberine, 9,10-dimethoxy-2,3-methylenedioxy-5,6-dihydrodibenzo[a,g]quinolizine, is an isoquinoline alkaloid of the protoberberine group which is commonly found in the Papaveraceae, Berberidaceae and other plant families (Bentley, 1998). Berberine is known as an antimicrobial agent and is used for the treatment of eye infections, gastrointestinal disorders and other diseases (Schmeller & Wink, 1998; Simeon et al., 1989). Recently, its interactions with nucleic acids and cells have been extensively investigated (Mazzini et al., 2003; Slaninová et al., 2001). The berberine skeleton is rather sensitive to nucleophilic attack, and 8-substituted-7,8-dihydroberberine derivatives, frequently claimed as genuine natural products, are easily formed (Marek et al., 2003). Here, we report the first crystal structure of a quaternary protoberberine alkaloid crystallizing with an organic (succinate? surely formate?) counteranion to give the title adduct, (I). These organic anions could play a significant role in plant tissues. \sch
The structure of the berberine cation in (I) is similar to that in other berberine ions reported in the literature (Abadi et al., 1984; Kariuki & Jones, 1995; Man et al., 2001). The interplanar angles between aromatic rings A/C, A/D and C/D are 13.36 (5), 13.21 (5) and 1.71 (4)°, respectively. The methoxy group at C9 lies almost in the plane of ring D [the deviations of atoms O3 and C16 from this plane are 0.0576 (11) and 0.134 (2) Å], whereas the methoxy group at C9 is almost perpendicular to the same plane [the C15—O3—C9—C10 torsion angle is −80.8 (2)° and the deviation of atom C15 from the plane of ring D is 1.147 (2) Å].
The berberine units are arranged in the centrosymmetric pairs with face-to-face geometry (Marek et al., 2002), forming columns parallel to the crystallographic a axis. The packing slip is probably formed in order to optimize σ–π and π–π stacking interactions (Hunter & Sanders, 1990). The formate anions and flexible succinic acid molecules fill up the space between these columns. Pairs of cations ?anions? and molecules, as (C4H6O4···HCOO−)2 hydrogen-bonded rings, are held together by several C—H···O contacts. The C—H···O interatomic distances for atoms H8 and H13 are rather short [H···O 2.27 (2) and 2.26 (2) Å, respectively] and should thus be classified as non-conventional weak hydrogen bonds rather than van der Waals contacts (Steiner & Desiraju, 1998; Desiraju & Steiner, 1999), supported by their bond directionalities [161.3(1.5)° and 148 (2)°, respectively] and assumed binding energies (Cannizzaro & Houk, 2002). We attribute these rather short C8—H···O and C13—H···O hydrogen bonds found in the crystal of (I) to the felicitous confluence of the pronounced electron-acceptor properties of the cationic berberine and the electron-donor properties of the anionic hydrogen-bonded (C4H6O4···HCOO−)2 macrocycle (Fig. 2 and Table 2).