Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270103017499/sk1650sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103017499/sk1650Isup2.hkl |
CCDC reference: 224664
Pergolide mesylate (1.64 kg) was dissolved in a stainless steel drum in aqueous ethanol (22 l of ethanol, 4 l of water and 3.3 g of ascorbic acid) under nitrogen at 333 K. Crystals of pergolide mesylate form II (1.13 kg, 68.9%) were obtained upon cooling the solution to 295 K and these crystals were isolated by filtration and dried in air.
H atoms were placed in calculated positions and refined riding on their attached C atoms in distances of 1.0 Å. Atoms H511 and H521 were located in difference Fourier maps and refined fixed. The absolute configuration could not be determined reliably via anomalous dispersion and was choosen to be consistent with that of the natural product.
Data collection: COLLECT (Nonius, 1997); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Watkin et al., 2001); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: CRYSTALS.
C19H27N2S+·CH3O3S− | Dx = 1.343 Mg m−3 |
Mr = 410.60 | Melting point: not measured K |
Trigonal, P3221 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 32 2" | Cell parameters from 4009 reflections |
a = 8.8510 (2) Å | θ = 1.0–26.0° |
c = 44.8860 (8) Å | µ = 0.29 mm−1 |
V = 3045.27 (11) Å3 | T = 293 K |
Z = 6 | Block, white |
F(000) = 1320 | 0.35 × 0.26 × 0.23 mm |
Nonius KappaCCD diffractometer | Rint = 0.02 |
Graphite monochromator | θmax = 26.0°, θmin = 1.4° |
ϕ and ω scans | h = −10→10 |
7908 measured reflections | k = −8→8 |
2389 independent reflections | l = −55→55 |
1937 reflections with I > 1.96σ(I) |
Refinement on F | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.030 | H-atom parameters constrained |
wR(F2) = 0.034 | Prince modified Chebychev polynomial (Watkin, 1994); W = [weight][1-(δF/6σF)2]2, with 0.551, 0.377 and 0.369 |
S = 1.15 | (Δ/σ)max = 0.000375 |
1937 reflections | Δρmax = 0.22 e Å−3 |
244 parameters | Δρmin = −0.23 e Å−3 |
C19H27N2S+·CH3O3S− | Z = 6 |
Mr = 410.60 | Mo Kα radiation |
Trigonal, P3221 | µ = 0.29 mm−1 |
a = 8.8510 (2) Å | T = 293 K |
c = 44.8860 (8) Å | 0.35 × 0.26 × 0.23 mm |
V = 3045.27 (11) Å3 |
Nonius KappaCCD diffractometer | 1937 reflections with I > 1.96σ(I) |
7908 measured reflections | Rint = 0.02 |
2389 independent reflections |
R[F2 > 2σ(F2)] = 0.030 | 244 parameters |
wR(F2) = 0.034 | H-atom parameters constrained |
S = 1.15 | Δρmax = 0.22 e Å−3 |
1937 reflections | Δρmin = −0.23 e Å−3 |
x | y | z | Uiso*/Ueq | ||
S1 | 0.0225 (1) | 0.2082 (1) | 0.287236 (17) | 0.0408 | |
S2 | 0.75195 (9) | 0.63950 (8) | 0.269633 (13) | 0.0265 | |
O1 | 0.8441 (3) | 0.7483 (3) | 0.24427 (4) | 0.0423 | |
O2 | 0.7400 (3) | 0.4696 (3) | 0.26815 (4) | 0.0406 | |
O3 | 0.5855 (3) | 0.6273 (3) | 0.27508 (4) | 0.0449 | |
N1 | 0.8724 (3) | 0.2581 (3) | 0.13712 (4) | 0.0315 | |
N2 | 0.4787 (3) | 0.1462 (3) | 0.25224 (4) | 0.0232 | |
C1 | 0.8867 (3) | 0.2171 (3) | 0.16622 (6) | 0.0295 | |
C2 | 0.7598 (3) | 0.2207 (3) | 0.18304 (5) | 0.0260 | |
C3 | 0.7082 (3) | 0.1864 (4) | 0.21541 (5) | 0.0259 | |
C4 | 0.5177 (3) | 0.1455 (3) | 0.21902 (5) | 0.0227 | |
C5 | 0.2942 (3) | 0.1055 (3) | 0.25720 (5) | 0.0270 | |
C6 | 0.2597 (3) | 0.2388 (3) | 0.24219 (5) | 0.0249 | |
C7 | 0.2921 (3) | 0.2389 (3) | 0.20885 (5) | 0.0274 | |
C8 | 0.4777 (3) | 0.2767 (3) | 0.20301 (5) | 0.0235 | |
C9 | 0.5242 (4) | 0.2896 (3) | 0.17023 (5) | 0.0269 | |
C10 | 0.4484 (4) | 0.3299 (3) | 0.14667 (5) | 0.0295 | |
C11 | 0.5184 (4) | 0.3524 (4) | 0.11764 (6) | 0.0326 | |
C12 | 0.6629 (4) | 0.3351 (3) | 0.11112 (6) | 0.0310 | |
C13 | 0.7362 (3) | 0.2894 (3) | 0.13471 (6) | 0.0289 | |
C14 | 0.6645 (3) | 0.2666 (3) | 0.16348 (5) | 0.0256 | |
C15 | 0.5150 (4) | 0.0259 (4) | 0.27087 (5) | 0.0280 | |
C16 | 0.5175 (5) | 0.0577 (4) | 0.30384 (6) | 0.0404 | |
C17 | 0.5497 (4) | −0.0671 (4) | 0.32167 (6) | 0.0362 | |
C18 | 0.0732 (3) | 0.1986 (4) | 0.24846 (6) | 0.0327 | |
C19 | 0.1359 (4) | 0.4391 (4) | 0.29398 (7) | 0.0440 | |
C30 | 0.8833 (4) | 0.7397 (4) | 0.30097 (6) | 0.0372 | |
H11 | 0.9762 | 0.1894 | 0.17389 | 0.0351* | |
H31 | 0.7871 | 0.2918 | 0.22747 | 0.0319* | |
H32 | 0.7182 | 0.0846 | 0.22249 | 0.0319* | |
H41 | 0.4427 | 0.0289 | 0.20956 | 0.0290* | |
H51 | 0.2734 | 0.1060 | 0.27909 | 0.0317* | |
H52 | 0.2126 | −0.0127 | 0.24887 | 0.0317* | |
H61 | 0.3404 | 0.3576 | 0.25041 | 0.0301* | |
H71 | 0.2750 | 0.3306 | 0.19901 | 0.0324* | |
H72 | 0.2075 | 0.1220 | 0.20039 | 0.0324* | |
H81 | 0.5540 | 0.3950 | 0.21178 | 0.0277* | |
H101 | 0.3442 | 0.3432 | 0.15030 | 0.0339* | |
H111 | 0.4617 | 0.3820 | 0.10113 | 0.0373* | |
H121 | 0.7121 | 0.3543 | 0.09051 | 0.0324* | |
H151 | 0.6313 | 0.0424 | 0.26498 | 0.0377* | |
H152 | 0.4223 | −0.0970 | 0.26662 | 0.0377* | |
H161 | 0.6114 | 0.1798 | 0.30824 | 0.0552* | |
H162 | 0.4019 | 0.0426 | 0.30981 | 0.0552* | |
H171 | 0.5499 | −0.0410 | 0.34335 | 0.0458* | |
H172 | 0.6656 | −0.0526 | 0.31603 | 0.0458* | |
H173 | 0.4561 | −0.1899 | 0.31760 | 0.0458* | |
H181 | 0.0538 | 0.2850 | 0.23721 | 0.0386* | |
H182 | −0.0087 | 0.0784 | 0.24095 | 0.0386* | |
H191 | 0.1177 | 0.4618 | 0.31513 | 0.0551* | |
H192 | 0.2634 | 0.4879 | 0.29023 | 0.0551* | |
H193 | 0.0901 | 0.4962 | 0.28032 | 0.0551* | |
H301 | 0.8981 | 0.8586 | 0.30360 | 0.0429* | |
H302 | 0.8264 | 0.6678 | 0.31910 | 0.0429* | |
H303 | 1.0001 | 0.7500 | 0.29805 | 0.0429* | |
H511 | 0.9329 | 0.2593 | 0.12508 | 0.0500* | |
H521 | 0.5525 | 0.2564 | 0.25908 | 0.0500* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0362 (4) | 0.0416 (4) | 0.0490 (4) | 0.0227 (4) | 0.0182 (3) | 0.0163 (3) |
S2 | 0.0266 (3) | 0.0243 (3) | 0.0249 (3) | 0.0099 (3) | −0.0043 (3) | −0.0025 (2) |
O1 | 0.0394 (12) | 0.0453 (12) | 0.0314 (9) | 0.013 (1) | −0.0026 (8) | 0.0111 (9) |
O2 | 0.0453 (13) | 0.025 (1) | 0.0503 (12) | 0.017 (1) | −0.015 (1) | −0.0102 (9) |
O3 | 0.0348 (12) | 0.0583 (15) | 0.0446 (11) | 0.0256 (11) | −0.0040 (9) | −0.008 (1) |
N1 | 0.0317 (12) | 0.0298 (12) | 0.029 (1) | 0.012 (1) | 0.0081 (9) | 0.001 (1) |
N2 | 0.0235 (11) | 0.022 (1) | 0.0244 (9) | 0.0113 (9) | 0.0006 (8) | −0.0001 (8) |
C1 | 0.0280 (14) | 0.0279 (14) | 0.0321 (12) | 0.0137 (12) | 0.0012 (11) | −0.0003 (11) |
C2 | 0.0262 (13) | 0.0222 (13) | 0.0273 (12) | 0.0104 (11) | 0.000 (1) | −0.002 (1) |
C3 | 0.0257 (13) | 0.0285 (14) | 0.0265 (12) | 0.0158 (12) | −0.001 (1) | −0.001 (1) |
C4 | 0.0263 (13) | 0.0238 (12) | 0.020 (1) | 0.014 (1) | −0.0011 (9) | −0.0006 (9) |
C5 | 0.0236 (12) | 0.0246 (13) | 0.0315 (11) | 0.0111 (11) | 0.003 (1) | 0.003 (1) |
C6 | 0.0206 (12) | 0.0242 (13) | 0.0309 (12) | 0.012 (1) | 0.001 (1) | 0.0018 (11) |
C7 | 0.0263 (14) | 0.0229 (13) | 0.0318 (12) | 0.0115 (12) | −0.0021 (11) | −0.001 (1) |
C8 | 0.0283 (14) | 0.0180 (12) | 0.0243 (12) | 0.0118 (11) | −0.002 (1) | −0.0013 (9) |
C9 | 0.0310 (14) | 0.0184 (12) | 0.0279 (12) | 0.0098 (11) | 0.0003 (11) | −0.001 (1) |
C10 | 0.0311 (15) | 0.0225 (13) | 0.0311 (12) | 0.0105 (12) | −0.0041 (11) | 0.0021 (11) |
C11 | 0.0411 (17) | 0.0248 (14) | 0.0270 (13) | 0.0126 (13) | −0.0054 (12) | 0.001 (1) |
C12 | 0.0344 (15) | 0.0208 (13) | 0.0252 (12) | 0.0044 (12) | 0.0013 (11) | 0.001 (1) |
C13 | 0.0289 (13) | 0.0194 (13) | 0.0307 (13) | 0.0063 (12) | 0.001 (1) | −0.002 (1) |
C14 | 0.0264 (13) | 0.0188 (13) | 0.0261 (11) | 0.0073 (11) | −0.000 (1) | −0.001 (1) |
C15 | 0.0375 (15) | 0.0302 (15) | 0.0250 (12) | 0.0234 (13) | −0.0019 (11) | 0.002 (1) |
C16 | 0.062 (2) | 0.0477 (18) | 0.0262 (12) | 0.0384 (17) | 0.0047 (13) | 0.0046 (12) |
C17 | 0.0485 (18) | 0.0378 (16) | 0.0287 (12) | 0.0264 (14) | 0.0029 (12) | 0.0042 (12) |
C18 | 0.0245 (13) | 0.0308 (15) | 0.0437 (15) | 0.0145 (11) | 0.0030 (11) | 0.0037 (12) |
C19 | 0.0491 (19) | 0.0526 (19) | 0.0371 (14) | 0.0306 (16) | 0.0119 (14) | 0.0056 (13) |
C30 | 0.0406 (17) | 0.0352 (16) | 0.0305 (12) | 0.0151 (13) | −0.0099 (12) | −0.0086 (12) |
S1—C18 | 1.810 (3) | C7—H72 | 1.000 |
S1—C19 | 1.796 (3) | C8—C9 | 1.517 (3) |
S2—O1 | 1.450 (2) | C8—H81 | 1.000 |
S2—O2 | 1.455 (2) | C9—C10 | 1.391 (4) |
S2—O3 | 1.443 (2) | C9—C14 | 1.389 (4) |
S2—C30 | 1.757 (3) | C10—C11 | 1.413 (4) |
N1—C1 | 1.378 (3) | C10—H101 | 1.000 |
N1—C13 | 1.369 (4) | C11—C12 | 1.393 (4) |
N1—H511 | 0.757 | C11—H111 | 1.000 |
N2—C4 | 1.531 (3) | C12—C13 | 1.403 (4) |
N2—C5 | 1.502 (3) | C12—H121 | 1.000 |
N2—C15 | 1.510 (3) | C13—C14 | 1.408 (3) |
N2—H521 | 0.914 | C15—C16 | 1.505 (3) |
C1—C2 | 1.367 (4) | C15—H151 | 1.000 |
C1—H11 | 1.000 | C15—H152 | 1.000 |
C2—C3 | 1.508 (3) | C16—C17 | 1.502 (4) |
C2—C14 | 1.411 (3) | C16—H161 | 1.000 |
C3—C4 | 1.546 (3) | C16—H162 | 1.000 |
C3—H31 | 1.000 | C17—H171 | 1.000 |
C3—H32 | 1.000 | C17—H172 | 1.000 |
C4—C8 | 1.550 (3) | C17—H173 | 1.000 |
C4—H41 | 1.000 | C18—H181 | 1.000 |
C5—C6 | 1.517 (3) | C18—H182 | 1.000 |
C5—H51 | 1.000 | C19—H191 | 1.000 |
C5—H52 | 1.000 | C19—H192 | 1.000 |
C6—C7 | 1.524 (3) | C19—H193 | 1.000 |
C6—C18 | 1.531 (4) | C30—H301 | 1.000 |
C6—H61 | 1.000 | C30—H302 | 1.000 |
C7—C8 | 1.527 (4) | C30—H303 | 1.000 |
C7—H71 | 1.000 | ||
C18—S1—C19 | 101.80 (13) | C7—C8—H81 | 104.55 |
O1—S2—O2 | 112.12 (14) | C9—C8—H81 | 106.70 |
O1—S2—O3 | 113.36 (13) | C8—C9—C10 | 127.5 (2) |
O2—S2—O3 | 112.75 (14) | C8—C9—C14 | 115.4 (2) |
O1—S2—C30 | 106.42 (13) | C10—C9—C14 | 116.9 (2) |
O2—S2—C30 | 104.25 (14) | C9—C10—C11 | 120.2 (3) |
O3—S2—C30 | 107.17 (14) | C9—C10—H101 | 119.87 |
C1—N1—C13 | 109.5 (2) | C11—C10—H101 | 119.90 |
C1—N1—H511 | 121.50 | C10—C11—C12 | 122.7 (3) |
C13—N1—H511 | 128.95 | C10—C11—H111 | 118.60 |
C4—N2—C5 | 111.32 (18) | C12—C11—H111 | 118.74 |
C4—N2—C15 | 114.11 (18) | C11—C12—C13 | 117.1 (2) |
C5—N2—C15 | 109.74 (19) | C11—C12—H121 | 121.41 |
C4—N2—H521 | 106.84 | C13—C12—H121 | 121.49 |
C5—N2—H521 | 108.49 | N1—C13—C12 | 134.3 (2) |
C15—N2—H521 | 106.01 | N1—C13—C14 | 106.1 (2) |
N1—C1—C2 | 109.4 (2) | C12—C13—C14 | 119.6 (3) |
N1—C1—H11 | 125.41 | C2—C14—C9 | 127.9 (2) |
C2—C1—H11 | 125.16 | C2—C14—C13 | 108.7 (2) |
C1—C2—C3 | 134.2 (2) | C9—C14—C13 | 123.4 (2) |
C1—C2—C14 | 106.2 (2) | N2—C15—C16 | 113.7 (2) |
C3—C2—C14 | 119.6 (2) | N2—C15—H151 | 108.48 |
C2—C3—C4 | 109.5 (2) | C16—C15—H151 | 108.35 |
C2—C3—H31 | 109.47 | N2—C15—H152 | 108.26 |
C4—C3—H31 | 109.46 | C16—C15—H152 | 108.56 |
C2—C3—H32 | 109.48 | H151—C15—H152 | 109.466 |
C4—C3—H32 | 109.45 | C15—C16—C17 | 112.1 (2) |
H31—C3—H32 | 109.467 | C15—C16—H161 | 108.85 |
N2—C4—C3 | 108.83 (19) | C17—C16—H161 | 109.23 |
N2—C4—C8 | 108.18 (18) | C15—C16—H162 | 108.65 |
C3—C4—C8 | 114.0 (2) | C17—C16—H162 | 108.47 |
N2—C4—H41 | 112.52 | H161—C16—H162 | 109.467 |
C3—C4—H41 | 106.30 | C16—C17—H171 | 109.10 |
C8—C4—H41 | 107.08 | C16—C17—H172 | 109.27 |
N2—C5—C6 | 111.4 (2) | H171—C17—H172 | 109.476 |
N2—C5—H51 | 108.98 | C16—C17—H173 | 110.03 |
C6—C5—H51 | 108.90 | H171—C17—H173 | 109.476 |
N2—C5—H52 | 108.98 | H172—C17—H173 | 109.476 |
C6—C5—H52 | 109.05 | S1—C18—C6 | 115.43 (19) |
H51—C5—H52 | 109.467 | S1—C18—H181 | 107.97 |
C5—C6—C7 | 109.0 (2) | C6—C18—H181 | 107.88 |
C5—C6—C18 | 110.6 (2) | S1—C18—H182 | 108.0 |
C7—C6—C18 | 111.2 (2) | C6—C18—H182 | 108.02 |
C5—C6—H61 | 109.73 | H181—C18—H182 | 109.467 |
C7—C6—H61 | 109.05 | S1—C19—H191 | 109.51 |
C18—C6—H61 | 107.31 | S1—C19—H192 | 109.3 |
C6—C7—C8 | 110.5 (2) | H191—C19—H192 | 109.476 |
C6—C7—H71 | 109.22 | S1—C19—H193 | 109.54 |
C8—C7—H71 | 109.21 | H191—C19—H193 | 109.476 |
C6—C7—H72 | 109.24 | H192—C19—H193 | 109.476 |
C8—C7—H72 | 109.16 | S2—C30—H301 | 109.4 |
H71—C7—H72 | 109.467 | S2—C30—H302 | 109.5 |
C4—C8—C7 | 112.3 (2) | H301—C30—H302 | 109.476 |
C4—C8—C9 | 110.6 (2) | S2—C30—H303 | 109.5 |
C7—C8—C9 | 113.9 (2) | H301—C30—H303 | 109.476 |
C4—C8—H81 | 108.32 | H302—C30—H303 | 109.476 |
Experimental details
Crystal data | |
Chemical formula | C19H27N2S+·CH3O3S− |
Mr | 410.60 |
Crystal system, space group | Trigonal, P3221 |
Temperature (K) | 293 |
a, c (Å) | 8.8510 (2), 44.8860 (8) |
V (Å3) | 3045.27 (11) |
Z | 6 |
Radiation type | Mo Kα |
µ (mm−1) | 0.29 |
Crystal size (mm) | 0.35 × 0.26 × 0.23 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 1.96σ(I)] reflections | 7908, 2389, 1937 |
Rint | 0.02 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.030, 0.034, 1.15 |
No. of reflections | 1937 |
No. of parameters | 244 |
No. of restraints | ? |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.23 |
Computer programs: COLLECT (Nonius, 1997), DENZO/SCALEPACK (Otwinowski & Minor, 1997), DENZO/SCALEPACK, SIR92 (Altomare et al., 1994), CRYSTALS (Watkin et al., 2001), ORTEP-3 (Farrugia, 1997), CRYSTALS.
Pergolide form Ia | |||
N1—H···O2 | x, y − 1, z + 1 | 2.853 | |
N2—H521···O2 | x + 1, y, z | 2.723 | |
Pergolide form IIb | Symmetry code | D ··· A | D—H···A |
N1—H511···O1 | x-y + 1, −y + 1, −z + 1/3 | 2.946 (3) | 176 |
N2—H521···O2 | 2.726 (2) | 166 |
Notes: (a) Ma et al. (1987); (b) this work. |
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Pergolide mesylate, (I), is a semisynthetic ergot derivative used as an important drug mainly in the treatment of Parkinson's disease (Wachtel, 1991). The crystal structure of pergolide mesylate [triclinic P1; a = 6.841 (2), b = 9.314 (2), c = 9.678 (2) Å, α = 64.42 (2), β = 69.67 (2), γ =76.74 (2)°] and the pergolide base have been described previously by Ma et al. (1987). The former structure refers to form I as described by Sprankle & Jensen (1992). Pergolide mesylate form II was described only in a mixture with form I based on only one new diffraction line that appeared in the powder diffraction data and by some differences in the fingerprint region of the IR spectrum (775, 607 and 544 cm−1). However, no more evidence of form II was ever reported. As well as the structures of pergolide and pergolide mesylate, the structure of pergolide sulfoxide, a pergolide metabolite exhibiting roughly equal pharmacological activity as pergolide, has been reported (Čejka et al., 1998).
Pergolide mesylate form II crystallizes in the trigonal space group P3221. Conformational analysis has shown that there are only subtle differences between the independent molecules in individual structures. The ergoline skeleton is virtually identical in all pergolide derivatives. Only one of the two independent molecules of pergolide sulfoxide differs in the orientation of the sulfoxy group (see Fig. 1). Although there are a number of coincidences of diffraction lines in powder diffractograms, pergolide mesylate forms I and II can be easily distinguished by the presence of the sole diffraction lines (014) 6.329 Å and (003) 14.96 Å in form II, and (001) 8.372 Å in form I, which can potentially serve also for the quantitative analysis of the mixtures.
The DTA thermogram for pergolide mesylate form II shows a sharp endotherm at 534.5 K (decomposition), which is identical, within experimental error, to pergolide mesylate form I. In addition to a number of subtle changes in the fingerprint region of the IR spectrum in the range 450–800 cm−1, there are also noticeable changes in the range 1400–1500 cm−1 (aliphatic C—H deformation), which can serve to discriminate between the two forms. More interestingly, changes in N—H deformation (~780 cm−1 for indole N—H), N+—H stretch (2556 cm−1 in form I and ~2600–2700 cm−1 in form II), and N—H stretch (3180 cm−1 in form I and 3200 cm−1 in form II for indole N—H) bands indicate the substantially different hydrogen-bond network in the individual forms. Although the same atoms and similar hydrogen bonds are utilized in the hydrogen-bond networks (see Table 2), the final arrangement is very different. In form I, the molecules form bridges to each other through the mesylate anions, forming simple narrow chains. In contrast, pergolide molecules and mesylate anions create zigzag screwed chains in several directions in form II. It should be noted that the orientations of the mesylate methyl groups are also different in both structures.