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In the title compound, potassium 2-butyl-4-chloro-1-{[2′-(5-tetrazolido)biphenyl-4-yl]methyl}-1H-imidazol-5-ylmethanol, K+·C22H22ClN6O−, the imidazole and tetrazole rings are at angles of 85.0 (2) and 51.8 (1)°, respectively, to the phenyl rings to which they are attached, while the dihedral angle between the latter two rings is 46.7 (1)°. The coordination sphere of the metal cation consists of six tetrazoyl N atoms, the methanol O atom and the π cloud of one of the phenyl rings. These interactions determine the formation of columns of molecular anions that lie parallel to the b axis, while hydrogen bonding contributes to intercolumnar cohesion. Far from the centre of the columns, the hydrocarbon chain is immersed in a hydrophobic environment.
Supporting information
CCDC reference: 192955
The title compound was obtained from Laboratorios Gador SA, Buenos Aires,
Argentina. Crystals of (I) suitable for X-ray diffraction were obtained on
slow evaporation of a water solution.
The positional parameters of the H atoms were constrained to have C—H
distances of 0.98 Å for primary, 0.99 Å for secondary and 0.95 Å for
aromatic H atoms, while O—H = 0.84 Å. The H atoms were treated as riding
and their isotropic displacement parameters were constrained to be 1.2 times
larger than those of their hosts (1.5 for methyl and OH groups). The atomic
displacement parameters of various atoms of the disordered part of losartan,
namely N51, C151, C161 and C171, were constrained using the EADP command in
SHELXL97 (Sheldrick, 1997).
Data collection: COLLECT (Nonius, 1997-2000); cell refinement: HKL SCALEPACK (Otwinowski & Minor, 1997); data reduction: HKL DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL/PC (Sheldrick, 1991); software used to prepare material for publication: PARST (Nardelli, 1995) and WinGX (Farrugia, 1999).
potassium
2-butyl-4-chloro-1-{[2'-(5-tetrazolido)biphenyl-4-yl]methyl}-1
H-imidazol- 5-ylmethanol
top
Crystal data top
K(C22H22ClN6O) | F(000) = 960 |
Mr = 461.01 | Dx = 1.381 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 15.5724 (3) Å | Cell parameters from 34378 reflections |
b = 7.4976 (2) Å | θ = 1.0–27.5° |
c = 24.2640 (5) Å | µ = 0.39 mm−1 |
β = 128.498 (1)° | T = 120 K |
V = 2217.16 (9) Å3 | Thin plate, colourless |
Z = 4 | 0.22 × 0.12 × 0.04 mm |
Data collection top
Nonius Kappa CCD area-detector diffractometer | 3184 reflections with I > 2σ(I) |
ϕ scans with κ at 0°, and ω scans | Rint = 0.026 |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | θmax = 25°, θmin = 2.9° |
Tmin = 0.920, Tmax = 0.985 | h = −18→18 |
7037 measured reflections | k = −8→8 |
3888 independent reflections | l = −28→28 |
Refinement top
Refinement on F2 | 0 restraints |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.043 | w = 1/[σ2(Fo2) + (0.0557P)2 + 1.228P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.116 | (Δ/σ)max = 0.001 |
S = 1.03 | Δρmax = 0.45 e Å−3 |
3888 reflections | Δρmin = −0.36 e Å−3 |
392 parameters | |
Crystal data top
K(C22H22ClN6O) | V = 2217.16 (9) Å3 |
Mr = 461.01 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 15.5724 (3) Å | µ = 0.39 mm−1 |
b = 7.4976 (2) Å | T = 120 K |
c = 24.2640 (5) Å | 0.22 × 0.12 × 0.04 mm |
β = 128.498 (1)° | |
Data collection top
Nonius Kappa CCD area-detector diffractometer | 3888 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | 3184 reflections with I > 2σ(I) |
Tmin = 0.920, Tmax = 0.985 | Rint = 0.026 |
7037 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.116 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.45 e Å−3 |
3888 reflections | Δρmin = −0.36 e Å−3 |
392 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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | Occ. (<1) |
K | −0.03166 (4) | 0.25891 (6) | −0.07829 (2) | 0.03292 (15) | |
Cl1 | 0.54908 (11) | 0.3801 (2) | 0.33591 (6) | 0.0641 (4) | 0.7 |
O1 | 0.25211 (11) | 0.6667 (2) | 0.17577 (8) | 0.0381 (4) | |
H1 | 0.3035 | 0.7395 | 0.2015 | 0.057* | |
N1 | 0.01100 (15) | −0.3752 (2) | −0.08435 (10) | 0.0387 (4) | |
N2 | −0.04356 (15) | −0.3117 (3) | −0.06134 (10) | 0.0416 (5) | |
N3 | −0.07054 (15) | −0.1437 (3) | −0.08049 (10) | 0.0382 (4) | |
N4 | −0.03420 (15) | −0.0924 (2) | −0.11621 (10) | 0.0368 (4) | |
N5 | 0.3764 (4) | 0.4284 (8) | 0.13590 (18) | 0.0305 (10) | 0.7 |
N6 | 0.5496 (3) | 0.3650 (5) | 0.2261 (3) | 0.0321 (7) | 0.7 |
C1 | 0.01533 (17) | −0.2366 (3) | −0.11699 (10) | 0.0312 (5) | |
C2 | 0.07333 (17) | −0.2391 (3) | −0.14743 (11) | 0.0353 (5) | |
C3 | 0.04853 (19) | −0.3729 (3) | −0.19560 (11) | 0.0438 (6) | |
H3 | −0.0038 | −0.4619 | −0.2073 | 0.053* | |
C4 | 0.0990 (2) | −0.3776 (4) | −0.22638 (13) | 0.0552 (7) | |
H4 | 0.0816 | −0.4695 | −0.2588 | 0.066* | |
C5 | 0.1748 (2) | −0.2488 (4) | −0.20992 (13) | 0.0564 (8) | |
H5 | 0.2093 | −0.2514 | −0.2313 | 0.068* | |
C6 | 0.20077 (19) | −0.1150 (4) | −0.16209 (12) | 0.0463 (6) | |
H6 | 0.253 | −0.0267 | −0.1511 | 0.056* | |
C7 | 0.15146 (17) | −0.1079 (3) | −0.12983 (11) | 0.0358 (5) | |
C8 | 0.18323 (17) | 0.0372 (3) | −0.07845 (11) | 0.0348 (5) | |
C9 | 0.1899 (2) | 0.2127 (3) | −0.09409 (13) | 0.0463 (6) | |
H9 | 0.1721 | 0.2395 | −0.1384 | 0.056* | |
C10 | 0.2220 (2) | 0.3490 (3) | −0.04642 (14) | 0.0482 (6) | |
H10 | 0.2262 | 0.4676 | −0.0584 | 0.058* | |
C11 | 0.24775 (17) | 0.3144 (3) | 0.01826 (12) | 0.0398 (5) | |
C12 | 0.24028 (17) | 0.1400 (3) | 0.03451 (12) | 0.0363 (5) | |
H12 | 0.2564 | 0.1146 | 0.0784 | 0.044* | |
C13 | 0.20965 (16) | 0.0037 (3) | −0.01275 (11) | 0.0338 (5) | |
H13 | 0.2065 | −0.115 | −0.0004 | 0.041* | |
C14 | 0.28056 (19) | 0.4642 (3) | 0.06942 (13) | 0.0483 (6) | |
H14A | 0.2838 | 0.5798 | 0.051 | 0.058* | |
H14B | 0.2228 | 0.4735 | 0.0749 | 0.058* | |
C15 | 0.3845 (6) | 0.4350 (10) | 0.1961 (3) | 0.0312 (13) | 0.7 |
C16 | 0.2923 (10) | 0.4911 (17) | 0.1973 (7) | 0.0386 (14) | 0.7 |
H16A | 0.2296 | 0.4113 | 0.1642 | 0.046* | 0.7 |
H16B | 0.3153 | 0.4691 | 0.2451 | 0.046* | 0.7 |
C17 | 0.4891 (3) | 0.3947 (5) | 0.2486 (2) | 0.0334 (8) | 0.7 |
C18 | 0.4782 (4) | 0.3871 (7) | 0.1564 (3) | 0.0367 (11) | 0.7 |
C19 | 0.5163 (13) | 0.4055 (17) | 0.1121 (9) | 0.032 (3) | 0.35 |
H19A | 0.591 | 0.4569 | 0.1404 | 0.038* | 0.35 |
H19B | 0.4661 | 0.4865 | 0.072 | 0.038* | 0.35 |
C20 | 0.5143 (5) | 0.2207 (9) | 0.0842 (3) | 0.0332 (13) | 0.35 |
H20A | 0.4439 | 0.1607 | 0.0644 | 0.04* | 0.35 |
H20B | 0.5737 | 0.1478 | 0.1243 | 0.04* | 0.35 |
C21 | 0.5296 (6) | 0.2265 (9) | 0.0288 (3) | 0.0414 (15) | 0.35 |
H21A | 0.6017 | 0.2802 | 0.0489 | 0.05* | 0.35 |
H21B | 0.472 | 0.3024 | −0.0109 | 0.05* | 0.35 |
C22 | 0.5238 (7) | 0.0401 (11) | 0.0012 (5) | 0.050 (2) | 0.35 |
H22A | 0.5872 | −0.0299 | 0.0388 | 0.075* | 0.35 |
H22B | 0.5243 | 0.0489 | −0.0389 | 0.075* | 0.35 |
H22C | 0.4561 | −0.0184 | −0.0138 | 0.075* | 0.35 |
Cl2 | 0.52707 (18) | 0.3704 (3) | 0.35444 (11) | 0.0369 (5) | 0.3 |
N51 | 0.3803 (12) | 0.411 (2) | 0.1564 (7) | 0.0305 (10) | 0.3 |
N61 | 0.5437 (7) | 0.3255 (11) | 0.2513 (4) | 0.0321 (17) | 0.3 |
C151 | 0.3737 (17) | 0.432 (3) | 0.2095 (12) | 0.0312 (13) | 0.3 |
C161 | 0.280 (3) | 0.478 (5) | 0.2044 (17) | 0.0386 (14) | 0.3 |
H16C | 0.2173 | 0.3941 | 0.1768 | 0.046* | 0.3 |
H16D | 0.3019 | 0.4847 | 0.2524 | 0.046* | 0.3 |
C171 | 0.4801 (9) | 0.3760 (15) | 0.2696 (5) | 0.0334 (8) | 0.3 |
C181 | 0.4842 (10) | 0.3469 (13) | 0.1833 (7) | 0.027 (2) | 0.3 |
C191 | 0.5224 (8) | 0.3115 (16) | 0.1412 (6) | 0.033 (2) | 0.3 |
H19C | 0.4608 | 0.2611 | 0.095 | 0.04* | 0.3 |
H19D | 0.5816 | 0.2211 | 0.1659 | 0.04* | 0.3 |
C201 | 0.5655 (9) | 0.4798 (16) | 0.1287 (6) | 0.039 (2) | 0.3 |
H20C | 0.5044 | 0.5651 | 0.099 | 0.047* | 0.3 |
H20D | 0.5941 | 0.4464 | 0.1034 | 0.047* | 0.3 |
C211 | 0.6589 (7) | 0.5713 (10) | 0.2002 (4) | 0.0437 (18) | 0.3 |
H21C | 0.6275 | 0.6265 | 0.2212 | 0.052* | 0.3 |
H21D | 0.7133 | 0.4808 | 0.2336 | 0.052* | 0.3 |
C221 | 0.7134 (8) | 0.7098 (13) | 0.1880 (5) | 0.056 (2) | 0.3 |
H22D | 0.7439 | 0.6547 | 0.1669 | 0.085* | 0.3 |
H22E | 0.7726 | 0.7651 | 0.233 | 0.085* | 0.3 |
H22F | 0.6597 | 0.8009 | 0.1561 | 0.085* | 0.3 |
C192 | 0.5000 (12) | 0.335 (2) | 0.1069 (10) | 0.038 (4) | 0.35 |
H19E | 0.4316 | 0.29 | 0.0624 | 0.046* | 0.35 |
H19F | 0.5558 | 0.2389 | 0.1278 | 0.046* | 0.35 |
C202 | 0.5419 (8) | 0.5052 (15) | 0.0913 (6) | 0.058 (3) | 0.35 |
H20E | 0.5929 | 0.5695 | 0.1365 | 0.07* | 0.35 |
H20F | 0.5843 | 0.4671 | 0.0755 | 0.07* | 0.35 |
C212 | 0.4563 (6) | 0.6285 (11) | 0.0401 (4) | 0.0519 (18) | 0.35 |
H21E | 0.4117 | 0.6641 | 0.0546 | 0.062* | 0.35 |
H21F | 0.4072 | 0.5672 | −0.0059 | 0.062* | 0.35 |
C222 | 0.5023 (8) | 0.7938 (12) | 0.0317 (5) | 0.066 (2) | 0.35 |
H22G | 0.5542 | 0.8515 | 0.0776 | 0.099* | 0.35 |
H22H | 0.4425 | 0.8766 | −0.0008 | 0.099* | 0.35 |
H22I | 0.5403 | 0.7606 | 0.0128 | 0.099* | 0.35 |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
K | 0.0327 (3) | 0.0268 (3) | 0.0327 (3) | 0.00300 (18) | 0.0171 (2) | 0.00025 (18) |
Cl1 | 0.0698 (8) | 0.0830 (9) | 0.0322 (6) | 0.0411 (6) | 0.0281 (5) | 0.0135 (5) |
O1 | 0.0268 (7) | 0.0344 (8) | 0.0419 (8) | 0.0012 (6) | 0.0158 (7) | −0.0019 (7) |
N1 | 0.0387 (10) | 0.0330 (10) | 0.0386 (10) | 0.0008 (8) | 0.0212 (9) | 0.0028 (8) |
N2 | 0.0403 (10) | 0.0428 (11) | 0.0372 (10) | −0.0040 (9) | 0.0219 (9) | 0.0034 (9) |
N3 | 0.0400 (10) | 0.0376 (11) | 0.0392 (10) | −0.0076 (8) | 0.0258 (9) | −0.0071 (8) |
N4 | 0.0421 (10) | 0.0306 (10) | 0.0436 (10) | 0.0018 (8) | 0.0296 (9) | 0.0003 (8) |
N5 | 0.0232 (10) | 0.0360 (16) | 0.025 (3) | 0.0025 (10) | 0.0115 (19) | −0.007 (2) |
N6 | 0.0243 (18) | 0.0334 (18) | 0.031 (2) | 0.0015 (14) | 0.0138 (18) | −0.0015 (15) |
C1 | 0.0328 (10) | 0.0277 (11) | 0.0251 (10) | 0.0038 (8) | 0.0140 (9) | 0.0006 (8) |
C2 | 0.0352 (11) | 0.0381 (12) | 0.0250 (10) | 0.0106 (9) | 0.0149 (9) | 0.0033 (9) |
C3 | 0.0400 (12) | 0.0479 (14) | 0.0318 (11) | 0.0063 (10) | 0.0165 (10) | −0.0059 (10) |
C4 | 0.0449 (14) | 0.079 (2) | 0.0341 (12) | 0.0046 (13) | 0.0211 (11) | −0.0203 (13) |
C5 | 0.0432 (14) | 0.091 (2) | 0.0350 (13) | 0.0018 (14) | 0.0244 (11) | −0.0138 (13) |
C6 | 0.0411 (12) | 0.0632 (16) | 0.0348 (12) | 0.0025 (12) | 0.0237 (11) | −0.0032 (11) |
C7 | 0.0353 (11) | 0.0394 (12) | 0.0275 (10) | 0.0105 (9) | 0.0170 (9) | 0.0041 (9) |
C8 | 0.0326 (11) | 0.0368 (12) | 0.0327 (11) | 0.0077 (9) | 0.0191 (9) | 0.0031 (9) |
C9 | 0.0593 (15) | 0.0397 (13) | 0.0395 (12) | 0.0126 (11) | 0.0306 (12) | 0.0100 (10) |
C10 | 0.0544 (15) | 0.0328 (13) | 0.0540 (15) | 0.0129 (11) | 0.0321 (13) | 0.0089 (11) |
C11 | 0.0322 (11) | 0.0389 (13) | 0.0457 (13) | 0.0074 (10) | 0.0228 (10) | −0.0042 (10) |
C12 | 0.0304 (11) | 0.0440 (13) | 0.0352 (11) | 0.0002 (9) | 0.0209 (9) | −0.0050 (10) |
C13 | 0.0307 (10) | 0.0359 (12) | 0.0335 (11) | 0.0034 (9) | 0.0193 (9) | 0.0017 (9) |
C14 | 0.0386 (12) | 0.0418 (14) | 0.0547 (15) | 0.0082 (11) | 0.0243 (12) | −0.0091 (11) |
C15 | 0.028 (2) | 0.0295 (13) | 0.038 (4) | 0.0018 (13) | 0.0210 (14) | −0.003 (2) |
C16 | 0.033 (3) | 0.038 (2) | 0.045 (3) | 0.002 (2) | 0.0249 (14) | 0.0108 (19) |
C17 | 0.0323 (15) | 0.0325 (17) | 0.028 (2) | 0.0045 (13) | 0.0151 (16) | −0.0009 (17) |
C18 | 0.029 (2) | 0.046 (3) | 0.031 (3) | 0.0073 (17) | 0.017 (2) | 0.0019 (19) |
C19 | 0.041 (7) | 0.025 (8) | 0.048 (7) | 0.007 (6) | 0.036 (7) | 0.012 (7) |
C20 | 0.038 (3) | 0.030 (4) | 0.033 (3) | 0.004 (3) | 0.023 (3) | 0.000 (3) |
C21 | 0.041 (3) | 0.053 (4) | 0.034 (3) | 0.006 (3) | 0.025 (3) | 0.008 (3) |
C22 | 0.060 (6) | 0.050 (6) | 0.046 (4) | 0.008 (4) | 0.036 (4) | −0.003 (4) |
Cl2 | 0.0420 (11) | 0.0328 (10) | 0.0241 (11) | 0.0032 (8) | 0.0148 (9) | −0.0029 (8) |
N51 | 0.0232 (10) | 0.0360 (16) | 0.025 (3) | 0.0025 (10) | 0.0115 (19) | −0.007 (2) |
N61 | 0.029 (4) | 0.031 (4) | 0.031 (5) | −0.003 (3) | 0.016 (4) | −0.006 (3) |
C151 | 0.028 (2) | 0.0295 (13) | 0.038 (4) | 0.0018 (13) | 0.0210 (14) | −0.003 (2) |
C161 | 0.033 (3) | 0.038 (2) | 0.045 (3) | 0.002 (2) | 0.0249 (14) | 0.0108 (19) |
C171 | 0.0323 (15) | 0.0325 (17) | 0.028 (2) | 0.0045 (13) | 0.0151 (16) | −0.0009 (17) |
C181 | 0.028 (5) | 0.024 (5) | 0.030 (7) | 0.006 (4) | 0.019 (6) | −0.004 (4) |
C191 | 0.024 (5) | 0.035 (6) | 0.037 (5) | 0.000 (4) | 0.017 (5) | −0.008 (5) |
C201 | 0.048 (6) | 0.033 (6) | 0.057 (7) | −0.003 (5) | 0.043 (6) | 0.002 (5) |
C211 | 0.054 (5) | 0.036 (4) | 0.057 (5) | 0.007 (4) | 0.042 (4) | 0.001 (4) |
C221 | 0.056 (5) | 0.060 (6) | 0.079 (6) | −0.008 (4) | 0.054 (5) | −0.018 (5) |
C192 | 0.022 (5) | 0.045 (10) | 0.041 (6) | 0.004 (6) | 0.016 (5) | 0.013 (10) |
C202 | 0.053 (5) | 0.080 (7) | 0.051 (5) | 0.007 (5) | 0.037 (5) | 0.014 (5) |
C212 | 0.049 (4) | 0.061 (5) | 0.048 (4) | −0.004 (4) | 0.031 (4) | −0.002 (4) |
C222 | 0.072 (6) | 0.061 (5) | 0.079 (6) | −0.003 (4) | 0.053 (5) | 0.007 (5) |
Geometric parameters (Å, º) top
K—O1i | 2.7535 (14) | C15—C16 | 1.513 (9) |
K—N4 | 2.7824 (18) | C16—H16A | 0.99 |
K—N2ii | 2.840 (2) | C16—H16B | 0.99 |
K—N1iii | 2.8479 (19) | C18—C192 | 1.49 (2) |
K—N3 | 3.0726 (19) | C18—C19 | 1.522 (15) |
K—N3ii | 3.2384 (19) | C19—C20 | 1.534 (14) |
K—N2iii | 3.265 (2) | C19—H19A | 0.99 |
K—C12 | 3.434 (2) | C19—H19B | 0.99 |
K—C11 | 3.450 (2) | C20—C21 | 1.506 (9) |
K—Ki | 4.8797 (9) | C20—H20A | 0.99 |
Cl1—C17 | 1.705 (4) | C20—H20B | 0.99 |
O1—C16 | 1.411 (13) | C21—C22 | 1.527 (11) |
O1—C161 | 1.52 (3) | C21—H21A | 0.99 |
O1—H1 | 0.84 | C21—H21B | 0.99 |
N1—C1 | 1.333 (3) | C22—H22A | 0.98 |
N1—N2 | 1.360 (3) | C22—H22B | 0.98 |
N2—N3 | 1.318 (3) | C22—H22C | 0.98 |
N3—N4 | 1.353 (2) | Cl2—C171 | 1.704 (9) |
N4—C1 | 1.335 (3) | N51—C151 | 1.363 (14) |
N5—C18 | 1.369 (7) | N51—C181 | 1.401 (18) |
N5—C14 | 1.380 (5) | N61—C181 | 1.305 (14) |
N5—C15 | 1.388 (5) | N61—C171 | 1.366 (11) |
N6—C18 | 1.335 (5) | C151—C161 | 1.43 (3) |
N6—C17 | 1.370 (5) | C151—C171 | 1.43 (2) |
C1—C2 | 1.481 (3) | C161—H16C | 0.99 |
C2—C3 | 1.400 (3) | C161—H16D | 0.99 |
C2—C7 | 1.408 (3) | C181—C191 | 1.492 (13) |
C3—C4 | 1.382 (3) | C191—C201 | 1.545 (15) |
C3—H3 | 0.95 | C191—H19C | 0.99 |
C4—C5 | 1.377 (4) | C191—H19D | 0.99 |
C4—H4 | 0.95 | C201—C211 | 1.566 (14) |
C5—C6 | 1.390 (4) | C201—H20C | 0.99 |
C5—H5 | 0.95 | C201—H20D | 0.99 |
C6—C7 | 1.398 (3) | C211—C221 | 1.483 (12) |
C6—H6 | 0.95 | C211—H21C | 0.99 |
C7—C8 | 1.488 (3) | C211—H21D | 0.99 |
C8—C9 | 1.391 (3) | C221—H22D | 0.98 |
C8—C13 | 1.399 (3) | C221—H22E | 0.98 |
C9—C10 | 1.383 (4) | C221—H22F | 0.98 |
C9—H9 | 0.95 | C192—C202 | 1.585 (17) |
C10—C11 | 1.381 (3) | C192—H19E | 0.99 |
C10—H10 | 0.95 | C192—H19F | 0.99 |
C11—C12 | 1.391 (3) | C202—C212 | 1.454 (12) |
C11—C14 | 1.508 (3) | C202—H20E | 0.99 |
C12—C13 | 1.381 (3) | C202—H20F | 0.99 |
C12—H12 | 0.95 | C212—C222 | 1.509 (11) |
C13—H13 | 0.95 | C212—H21E | 0.99 |
C14—N51 | 1.715 (13) | C212—H21F | 0.99 |
C14—H14A | 0.99 | C222—H22G | 0.98 |
C14—H14B | 0.99 | C222—H22H | 0.98 |
C15—C17 | 1.336 (8) | C222—H22I | 0.98 |
| | | |
O1i—K—N4 | 98.88 (5) | O1—C16—C15 | 117.3 (5) |
O1i—K—N2ii | 111.37 (5) | O1—C161—C151 | 104.3 (19) |
N4—K—N2ii | 115.91 (6) | O1—C16—H16A | 106.1 |
O1i—K—N1iii | 88.09 (5) | C15—C16—H16A | 106.5 |
N4—K—N1iii | 148.28 (5) | O1—C16—H16B | 110.1 |
N2ii—K—N1iii | 89.48 (6) | C15—C16—H16B | 108.6 |
O1i—K—N3 | 93.29 (5) | H16A—C16—H16B | 107.7 |
N4—K—N3 | 26.12 (5) | C15—C17—N6 | 113.0 (3) |
N2ii—K—N3 | 95.06 (5) | C15—C17—Cl1 | 126.8 (3) |
N1iii—K—N3 | 174.40 (5) | N6—C17—Cl1 | 120.2 (3) |
O1i—K—N3ii | 120.17 (5) | N6—C18—N5 | 110.6 (4) |
N4—K—N3ii | 92.08 (5) | N6—C18—C192 | 124.1 (7) |
N2ii—K—N3ii | 23.91 (5) | N5—C18—C192 | 124.0 (7) |
N1iii—K—N3ii | 111.14 (5) | N6—C18—C19 | 121.5 (7) |
N3—K—N3ii | 72.80 (5) | N5—C18—C19 | 126.5 (7) |
O1i—K—N2iii | 76.72 (5) | C18—C19—C20 | 108.6 (9) |
N4—K—N2iii | 169.99 (5) | C18—C19—H19A | 110.6 |
N2ii—K—N2iii | 74.09 (6) | C20—C19—H19A | 110.5 |
N1iii—K—N2iii | 24.52 (5) | C18—C19—H19B | 109.6 |
N3—K—N2iii | 160.86 (5) | C20—C19—H19B | 109.5 |
N3ii—K—N2iii | 97.91 (5) | H19A—C19—H19B | 108.1 |
O1i—K—C12 | 175.48 (5) | C21—C20—C19 | 113.4 (8) |
N4—K—C12 | 76.96 (5) | C21—C20—H20A | 108.9 |
N2ii—K—C12 | 72.37 (5) | C19—C20—H20A | 109.6 |
N1iii—K—C12 | 94.57 (5) | C21—C20—H20B | 108.8 |
N3—K—C12 | 83.73 (5) | C19—C20—H20B | 108.4 |
N3ii—K—C12 | 62.20 (5) | H20A—C20—H20B | 107.6 |
N2iii—K—C12 | 107.10 (5) | C20—C21—C22 | 111.4 (6) |
O1i—K—C11 | 158.41 (5) | C20—C21—H21A | 109.5 |
N4—K—C11 | 95.22 (5) | C22—C21—H21A | 109.1 |
N2ii—K—C11 | 76.34 (6) | C20—C21—H21B | 109.5 |
N1iii—K—C11 | 71.51 (5) | C22—C21—H21B | 109.2 |
N3—K—C11 | 106.37 (5) | H21A—C21—H21B | 108 |
N3ii—K—C11 | 75.30 (5) | C21—C22—H22A | 109.4 |
N2iii—K—C11 | 86.68 (5) | C21—C22—H22B | 109.8 |
C12—K—C11 | 23.31 (6) | H22A—C22—H22B | 109.5 |
C16—O1—Ki | 122.4 (5) | C21—C22—H22C | 109.2 |
C16—O1—H1 | 109.5 | H22A—C22—H22C | 109.5 |
C1—N1—N2 | 104.27 (18) | H22B—C22—H22C | 109.5 |
N3—N2—N1 | 109.46 (17) | C181—N61—C171 | 106.8 (8) |
N2—N3—N4 | 109.20 (17) | N51—C151—C161 | 128 (2) |
C1—N4—N3 | 104.76 (18) | N51—C151—C171 | 102.0 (14) |
C14—N5—C18 | 129.4 (3) | C161—C151—C171 | 129.2 (19) |
C14—N5—C15 | 123.1 (5) | C151—C161—H16C | 115.5 |
C15—N5—C18 | 107.5 (5) | C151—C161—H16D | 109 |
C18—N6—C17 | 104.3 (4) | H16C—C161—H16D | 107.6 |
C14—N51—C181 | 123.5 (11) | N61—C171—C151 | 111.5 (10) |
C14—N51—C151 | 126.4 (16) | N61—C171—Cl2 | 122.2 (8) |
C151—N51—C181 | 110.1 (14) | C151—C171—Cl2 | 126.3 (10) |
N1—C1—N4 | 112.31 (19) | N61—C181—N51 | 109.7 (9) |
N1—C1—C2 | 123.94 (18) | N61—C181—C191 | 124.9 (10) |
N4—C1—C2 | 123.68 (18) | N51—C181—C191 | 125.4 (12) |
C3—C2—C7 | 119.4 (2) | C181—C191—C201 | 113.3 (9) |
C3—C2—C1 | 119.3 (2) | C181—C191—H19C | 108.9 |
C7—C2—C1 | 121.32 (19) | C201—C191—H19C | 108.9 |
C4—C3—C2 | 121.0 (2) | C181—C191—H19D | 108.9 |
C4—C3—H3 | 119.5 | C201—C191—H19D | 108.9 |
C2—C3—H3 | 119.5 | H19C—C191—H19D | 107.7 |
C5—C4—C3 | 119.9 (2) | C191—C201—C211 | 111.0 (9) |
C5—C4—H4 | 120 | C191—C201—H20C | 109.4 |
C3—C4—H4 | 120 | C211—C201—H20C | 109.4 |
C4—C5—C6 | 120.0 (2) | C191—C201—H20D | 109.4 |
C4—C5—H5 | 120 | C211—C201—H20D | 109.4 |
C6—C5—H5 | 120 | H20C—C201—H20D | 108 |
C5—C6—C7 | 121.3 (2) | C221—C211—C201 | 109.7 (8) |
C5—C6—H6 | 119.4 | C221—C211—H21C | 109.7 |
C7—C6—H6 | 119.4 | C201—C211—H21C | 109.7 |
C6—C7—C2 | 118.4 (2) | C221—C211—H21D | 109.7 |
C6—C7—C8 | 119.0 (2) | C201—C211—H21D | 109.7 |
C2—C7—C8 | 122.59 (19) | H21C—C211—H21D | 108.2 |
C9—C8—C13 | 117.5 (2) | C211—C221—H22D | 109.5 |
C9—C8—C7 | 120.35 (19) | C211—C221—H22E | 109.5 |
C13—C8—C7 | 122.1 (2) | H22D—C221—H22E | 109.5 |
C10—C9—C8 | 121.3 (2) | C211—C221—H22F | 109.5 |
C10—C9—H9 | 119.3 | H22D—C221—H22F | 109.5 |
C8—C9—H9 | 119.3 | H22E—C221—H22F | 109.5 |
C11—C10—C9 | 120.6 (2) | C18—C192—C202 | 108.2 (12) |
C11—C10—H10 | 119.8 | C18—C192—H19E | 109.9 |
C9—C10—H10 | 119.6 | C202—C192—H19E | 109.6 |
C10—C11—C12 | 118.8 (2) | C18—C192—H19F | 110.3 |
C10—C11—C14 | 120.3 (2) | C202—C192—H19F | 110.3 |
C12—C11—C14 | 120.8 (2) | H19E—C192—H19F | 108.6 |
C13—C12—C11 | 120.5 (2) | C212—C202—C192 | 115.0 (9) |
C13—C12—H12 | 119.8 | C212—C202—H20E | 108.3 |
C11—C12—H12 | 119.8 | C192—C202—H20E | 107.1 |
C12—C13—C8 | 121.2 (2) | C212—C202—H20F | 109.3 |
C12—C13—H13 | 119.4 | C192—C202—H20F | 109.4 |
C8—C13—H13 | 119.4 | H20E—C202—H20F | 107.5 |
N5—C14—C11 | 112.5 (3) | C202—C212—C222 | 112.2 (7) |
N51—C14—C11 | 115.1 (6) | C202—C212—H21E | 109.9 |
N5—C14—H14A | 112.1 | C222—C212—H21E | 108.9 |
C11—C14—H14A | 111.6 | C202—C212—H21F | 108.8 |
N51—C14—H14A | 119.7 | C222—C212—H21F | 109 |
N5—C14—H14B | 105.6 | H21E—C212—H21F | 107.8 |
C11—C14—H14B | 107 | C212—C222—H22G | 109.5 |
N51—C14—H14B | 93 | C212—C222—H22H | 109.6 |
H14A—C14—H14B | 107.7 | H22G—C222—H22H | 109.5 |
C17—C15—N5 | 104.6 (4) | C212—C222—H22I | 109.4 |
C17—C15—C16 | 130.8 (6) | H22G—C222—H22I | 109.5 |
N5—C15—C16 | 124.4 (7) | H22H—C222—H22I | 109.5 |
| | | |
C1—N1—N2—N3 | 0.5 (2) | N5—C15—C17—N6 | 0.9 (7) |
N1—N2—N3—N4 | −0.2 (2) | C16—C15—C17—N6 | −174.6 (8) |
N2—N3—N4—C1 | −0.2 (2) | N5—C15—C17—Cl1 | −179.6 (4) |
N2—N1—C1—N4 | −0.7 (2) | C16—C15—C17—Cl1 | 5.0 (11) |
N2—N1—C1—C2 | 176.33 (18) | C18—N6—C17—C15 | −0.4 (6) |
N3—N4—C1—N1 | 0.6 (2) | C18—N6—C17—Cl1 | −180.0 (3) |
N3—N4—C1—C2 | −176.46 (18) | C17—N6—C18—N5 | −0.3 (5) |
N1—C1—C2—C3 | 54.0 (3) | C17—N6—C18—C192 | −167.6 (8) |
N4—C1—C2—C3 | −129.3 (2) | C17—N6—C18—C19 | 166.7 (7) |
N1—C1—C2—C7 | −127.1 (2) | C14—N5—C18—N6 | 178.9 (5) |
N4—C1—C2—C7 | 49.6 (3) | C15—N5—C18—N6 | 0.8 (7) |
C7—C2—C3—C4 | −0.4 (3) | C14—N5—C18—C19 | 12.8 (11) |
C1—C2—C3—C4 | 178.5 (2) | C14—N5—C18—C192 | −13.7 (11) |
C2—C3—C4—C5 | −0.2 (4) | C15—N5—C18—C192 | 168.2 (9) |
C3—C4—C5—C6 | 0.4 (4) | C15—N5—C18—C19 | −165.3 (8) |
C4—C5—C6—C7 | 0.1 (4) | N6—C18—C19—C20 | 93.7 (11) |
C5—C6—C7—C2 | −0.7 (3) | N5—C18—C19—C20 | −101.6 (9) |
C5—C6—C7—C8 | 179.4 (2) | C18—C19—C20—C21 | 169.1 (7) |
C3—C2—C7—C6 | 0.8 (3) | C19—C20—C21—C22 | −178.4 (8) |
C1—C2—C7—C6 | −178.09 (19) | N5—C14—N51—C151 | 153 (5) |
C3—C2—C7—C8 | −179.23 (19) | C11—C14—N51—C151 | −125.6 (16) |
C1—C2—C7—C8 | 1.9 (3) | N5—C14—N51—C181 | −24 (3) |
C6—C7—C8—C9 | 46.2 (3) | C11—C14—N51—C181 | 57.5 (14) |
C2—C7—C8—C9 | −133.8 (2) | C181—N51—C151—C161 | −173 (2) |
C6—C7—C8—C13 | −132.4 (2) | C14—N51—C151—C161 | 9 (4) |
C2—C7—C8—C13 | 47.7 (3) | C181—N51—C151—C171 | 0.0 (19) |
C13—C8—C9—C10 | 0.3 (3) | C14—N51—C151—C171 | −177.2 (12) |
C7—C8—C9—C10 | −178.3 (2) | C181—N61—C171—C151 | 0.3 (14) |
C8—C9—C10—C11 | −0.4 (4) | C181—N61—C171—Cl2 | −179.5 (8) |
C9—C10—C11—C12 | −0.4 (4) | N51—C151—C171—N61 | −0.2 (18) |
C9—C10—C11—C14 | −178.8 (2) | C161—C151—C171—N61 | 173 (2) |
C10—C11—C12—C13 | 1.2 (3) | N51—C151—C171—Cl2 | 179.6 (11) |
C14—C11—C12—C13 | 179.67 (19) | C161—C151—C171—Cl2 | −7 (3) |
C11—C12—C13—C8 | −1.3 (3) | C171—N61—C181—N51 | −0.3 (12) |
C9—C8—C13—C12 | 0.6 (3) | C171—N61—C181—C191 | 178.5 (10) |
C7—C8—C13—C12 | 179.16 (19) | C151—N51—C181—N61 | 0.2 (18) |
C18—N5—C14—C11 | 56.9 (7) | C14—N51—C181—N61 | 177.5 (10) |
C15—N5—C14—C11 | −125.2 (6) | C151—N51—C181—C191 | −178.6 (14) |
C10—C11—C14—N5 | −129.7 (3) | C14—N51—C181—C191 | −1.3 (19) |
C12—C11—C14—N5 | 51.9 (3) | N61—C181—C191—C201 | −95.2 (12) |
C10—C11—C14—N51 | −143.4 (6) | N51—C181—C191—C201 | 83.4 (14) |
C12—C11—C14—N51 | 38.2 (6) | C181—C191—C201—C211 | 55.4 (12) |
C18—N5—C15—C17 | −1.0 (7) | C191—C201—C211—C221 | 168.9 (8) |
C14—N5—C15—C17 | −179.2 (5) | N6—C18—C192—C202 | −96.2 (10) |
C18—N5—C15—C16 | 174.8 (8) | N5—C18—C192—C202 | 98.1 (10) |
C14—N5—C15—C16 | −3.4 (11) | C19—C18—C192—C202 | −6 (2) |
C17—C15—C16—O1 | 112.8 (9) | C18—C192—C202—C212 | −79.4 (13) |
C171—C151—C161—O1 | 122.7 (19) | C192—C202—C212—C222 | 175.9 (11) |
N5—C15—C16—O1 | −61.9 (14) | | |
Symmetry codes: (i) −x, −y+1, −z; (ii) −x, −y, −z; (iii) x, y+1, z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N6iv | 0.84 | 2.05 | 2.874 (4) | 167 |
Symmetry code: (iv) −x+1, y+1/2, −z+1/2. |
Experimental details
Crystal data |
Chemical formula | K(C22H22ClN6O) |
Mr | 461.01 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 120 |
a, b, c (Å) | 15.5724 (3), 7.4976 (2), 24.2640 (5) |
β (°) | 128.498 (1) |
V (Å3) | 2217.16 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.39 |
Crystal size (mm) | 0.22 × 0.12 × 0.04 |
|
Data collection |
Diffractometer | Nonius Kappa CCD area-detector diffractometer |
Absorption correction | Multi-scan (SORTAV; Blessing, 1995) |
Tmin, Tmax | 0.920, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7037, 3888, 3184 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.595 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.116, 1.03 |
No. of reflections | 3888 |
No. of parameters | 392 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.45, −0.36 |
Selected geometric parameters (Å, º) topK—O1i | 2.7535 (14) | K—N3ii | 3.2384 (19) |
K—N4 | 2.7824 (18) | K—N2iii | 3.265 (2) |
K—N2ii | 2.840 (2) | K—C12 | 3.434 (2) |
K—N1iii | 2.8479 (19) | Cl1—C17 | 1.705 (4) |
K—N3 | 3.0726 (19) | Cl2—C171 | 1.704 (9) |
| | | |
C14—N5—C18 | 129.4 (3) | C151—N51—C181 | 110.1 (14) |
C14—N5—C15 | 123.1 (5) | N5—C14—C11 | 112.5 (3) |
C15—N5—C18 | 107.5 (5) | N51—C14—C11 | 115.1 (6) |
C14—N51—C181 | 123.5 (11) | O1—C16—C15 | 117.3 (5) |
C14—N51—C151 | 126.4 (16) | O1—C161—C151 | 104.3 (19) |
| | | |
N4—C1—C2—C7 | 49.6 (3) | C12—C11—C14—N51 | 38.2 (6) |
C2—C7—C8—C13 | 47.7 (3) | C17—C15—C16—O1 | 112.8 (9) |
C12—C11—C14—N5 | 51.9 (3) | C171—C151—C161—O1 | 122.7 (19) |
Symmetry codes: (i) −x, −y+1, −z; (ii) −x, −y, −z; (iii) x, y+1, z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N6iv | 0.84 | 2.05 | 2.874 (4) | 167 |
Symmetry code: (iv) −x+1, y+1/2, −z+1/2. |
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Losartan potassium, (I), is a potent and orally effective pharmaceutical product used for the treatment of arterial hypertension (Birkenhager & de Leeuw, 1999; Goa & Wagstaff, 1996; Gavras & Salerno, 1996). Designed as a peptidomimetic of the hormone angiotensin II, devoid of partial agonist activity and with a good oral bioavailability (Johnson et al., 1990), it acts by selectively binding to and blocking the angiotensin II type 1 receptor, thus interfering with the renin-angiotensin system, an important regulator of normal blood pressure (Wexler et al., 1995). \sch
Structurally, losartan is a biphenyltetrazole ring system attached to a substituted imidazole ring through a methylene spacer. Recently, a single-crystal X-ray determination of the structure of the free acid of losartan (ethanol solvate) was reported by Okazaki et al. (1998). However, in the final publication, the crystal structure is not actually described and only includes an ellipsoid plot. Also, only the unit-cell parameters of this structure are available from the Cambridge Structural Database (CSD; Allen et al., 1983) [CSD refcode PUSMIZ; Okazaki et al., 1998]. By spectroscopic (Raghavan et al., 1993) and thermal (Wu et al., 1993) powder diffraction studies, two polymorphic modifications of the drug have been identified. Unfortunately, we could obtain single crystals of only one of the two polymorphs. The structure of (I) has been investigated by our group as part of an ongoing study of biologically active pharmaceuticals (Vega et al., 2001), in this case, a specific ligand of the angiotensin II receptor.
Losartan potassium, (I), crystallizes in space group P21/c with one molecular anion and one K+ cation in the asymmetric unit (Fig. 1). In the molecular anion, the C1—N1—N2—N3—N4 tetrazole ring is affected by electron delocalization of the single negative charge among its atoms, and the bond lengths range from 1.318 (3) Å for N2—N3 to 1.360 (3) Å for N1—N2. The ring is planar, with a mean deviation from the plane of 0.0023 Å. The phenyl rings of the biphenyltetrazole, C2—C7 and C8—C13, sustain a mutual dihedral angle of 46.7 (1)°, while the dihedral angle between the tetrazole ring and the former is 51.8 (1)°. Such an arrangement is observed in nearly all structures of the biphenyltetrazole class of drugs, with the dihedral angle between the planes of the phenyl rings in the range 41.7–51.3°, and the phenyl and tetrazole rings sustaining a dihedral angle in the range 52.4–58.8° (data from 13 structures deposited within the CSD; version?). The C8—C13 phenyl ring is nearly perpendicular with respect to the plane of the N5—C15—N6—C17—C18 imidazole ring [dihedral angle 85.0 (2)°], while the hydroxymethyl group is oriented in the opposite direction in relation to the former [C17—C15—C16—O1 112.8 (9)° and C15—N5—C14—C11 - 125.2 (6)°].
On inspecting Fig. 1, it seems that the methylene spacer atom (C14) functions like a `hinge' connecting the least perturbed part of the structure, the biphenyltetrazole, with the most agitated part, the imidazole. Thermal motion appears to be conspicuous for the members and substituents of this ring, and it runs approximately in the direction of the largest atomic displacement parameter of atom Cl1.
The final structure was modelled with a major component (N5/N6/Cl1/C15—C18) accounting for 70% of the occupancy, and a minor component (30%) consisting of the imidazole ring (N51/N61/Cl2/C151—C181) and the C191—C221 butyl chain. In the major component, the butyl chain attached to C18 was further split over two positions of equal occupancy (35%), C19—C22 and C192—C222. Neither imidazole ring deviates significantly from planarity and they are separated by less than 7°. The three disordered chains have extended conformations, as indicated by the torsion angles C19—C20—C21—C22 [-178.4 (8)°], C191—C201—C211—C221 [168.9 (8)°] and C192—C202—C212—C222 [175.9 (11)°]. The first chain is oriented below the plane of the imidazole ring, and in the opposite direction with respect to the others, as indicated by the torsion angles N5—C18—C19—C20 [-101.6 (9)°], N5—C18—C192—C202 [98.1 (10)°] and N51—C181—C191—C201 [83.4 (14)°].
This behaviour may be explained by considering the way in which the packing of the crystal is achieved. From Fig. 2, it is clear that the K+ cation is `nested' within the biphenyltetrazole, where it is coordinated by several of its atoms. In contrast, the imidazole only coordinates to the K+ cation through atom O1. Thus, the members and substituents of the imidazole ring, excepting atom O1, have a less interconnected environment, so that they pivot without difficulty around atom C14 by bending the C16 bond angle (Table 2). In addition, the more hydrophobic atoms are stretched far away from the metal centre, thus creating an apolar environment, within which the butyl chain is able to rotate freely around the Cimidazole—Cbutyl bond. As a possible consequence of this motion, the atoms of the chain and those of the ring are highly agitated and disordered.
The coordination sphere of the K+ cation consists of the π cloud of the C8—C13 ring, the methanolic O atom and three pairs of tetrazoyl N atoms from three symmetry-related molecular anions (Fig. 2). The K···C(π) contact distances are within a narrow range, from K···C12 3.434 (2) Å to K···C8 3.739 (2) Å, while atom N4 forms the shortest one of the six K···N contacts. Of the remaining N atoms participating in the coordination sphere of the K+ cation, only N1 acts, like N4, as a monodentate ligand; in contrast, atoms N2 and N3, located in the outermost edge of the tetrazole ring, function as bridging ligands and enable a K···Ki contact distance of 4.88 Å between metal centres [symmetry code: (i) -x, 1 - y, -z]. To complete the coordination sphere, a fourth molecular anion donates the O1i monodentate ligand, so that the metal cation is surrounded by an eightfold polyhedron, in which the contact distances are K···N (average) 3.00 Å, K···O 2.75 Å and K···Cg 3.31 Å (Cg is the centroid of the C8—C13 ring).
These interactions contribute greatly to the packing of the crystal, which consists of chains of molecular anions formed by [010]-translated losartan molecules coordinated to the metal cation by atoms N3 and N4, the π cloud of the C8—C13 phenyl ring and atoms N1 and N2ii [symmetry code:(ii) x, 1 + y, z]. Meanwhile, the K+ cation is coordinated by centrosymmetrically related molecular anions via atoms N2, N3iii and O1i [symmetry code: (iii) -x, -y, -z], and hence a pair of parallel chains pack into a column. Inside this column, the polar parts of the losartan molecule are oriented toward the metal cation, while the hydrophobic parts project outside as far as possible. Parallel columns are hydrogen bonded through the O1—H1···N6 interaction (Table 2). In this way, they interdigitate, by juxtaposition at the imidazole of screw-related chains, and the offset between a pair of interdigitated chains is equal to 0.5 × d010.