| Literature DB >> 21582807 |
Feng Shi1, Dian-Xiang Zhou, Shu-Jiang Tu.
Abstract
In the mol-ecule of the title compound, C(27)H(21)ClN(2)O(4), the dihedral angle between theEntities:
Year: 2009 PMID: 21582807 PMCID: PMC2969224 DOI: 10.1107/S1600536809021084
Source DB: PubMed Journal: Acta Crystallogr Sect E Struct Rep Online ISSN: 1600-5368
| C27H21ClN2O4 | |
| Monoclinic, | Melting point = 508–509 K |
| Hall symbol: -P 2yn | Mo |
| Cell parameters from 1079 reflections | |
| θ = 2.4–19.9° | |
| µ = 0.21 mm−1 | |
| β = 100.232 (7)° | |
| Block, yellow | |
| 0.28 × 0.15 × 0.12 mm |
| Bruker SMART CCD area-detector diffractometer | 3913 independent reflections |
| Radiation source: fine-focus sealed tube | 1802 reflections with |
| graphite | |
| φ and ω scans | θmax = 25.0°, θmin = 2.0° |
| Absorption correction: multi-scan ( | |
| 11368 measured reflections |
| Refinement on | Primary atom site location: structure-invariant direct methods |
| Least-squares matrix: full | Secondary atom site location: difference Fourier map |
| Hydrogen site location: inferred from neighbouring sites | |
| H-atom parameters constrained | |
| 3913 reflections | (Δ/σ)max < 0.001 |
| 307 parameters | Δρmax = 0.25 e Å−3 |
| 0 restraints | Δρmin = −0.28 e Å−3 |
| 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 |
| Cl1 | 0.72987 (15) | 0.38409 (13) | 0.15930 (11) | 0.0740 (6) | |
| O1 | 0.5201 (3) | 1.0941 (3) | 0.2030 (2) | 0.0537 (10) | |
| O2 | 0.5296 (3) | 1.0511 (3) | 0.0810 (2) | 0.0620 (11) | |
| O3 | 0.0934 (3) | 0.7208 (3) | 0.0853 (2) | 0.0498 (10) | |
| O4 | 0.2460 (3) | 0.6755 (3) | 0.1814 (2) | 0.0502 (10) | |
| N1 | 0.3811 (4) | 0.8428 (4) | 0.2747 (3) | 0.0503 (12) | |
| H1 | 0.3691 | 0.7767 | 0.2525 | 0.060* | |
| N2 | 0.2308 (4) | 0.9098 (4) | −0.0373 (3) | 0.0517 (12) | |
| H2 | 0.3081 | 0.9226 | −0.0367 | 0.062* | |
| C1 | 0.5027 (5) | 1.0208 (4) | 0.1418 (4) | 0.0487 (14) | |
| C2 | 0.4502 (4) | 0.9143 (4) | 0.1609 (3) | 0.0385 (12) | |
| C3 | 0.4320 (4) | 0.9225 (4) | 0.2347 (3) | 0.0388 (12) | |
| C4 | 0.4770 (5) | 1.0372 (4) | 0.2651 (3) | 0.0458 (13) | |
| H4A | 0.4105 | 1.0809 | 0.2810 | 0.055* | |
| H4B | 0.5438 | 1.0287 | 0.3085 | 0.055* | |
| C5 | 0.2134 (4) | 0.7262 (4) | 0.1207 (3) | 0.0407 (13) | |
| C6 | 0.2842 (4) | 0.7961 (4) | 0.0774 (3) | 0.0384 (12) | |
| C7 | 0.2060 (4) | 0.8381 (4) | 0.0164 (3) | 0.0414 (13) | |
| C8 | 0.0777 (4) | 0.7922 (5) | 0.0181 (3) | 0.0482 (14) | |
| H8A | 0.0203 | 0.8548 | 0.0217 | 0.058* | |
| H8B | 0.0473 | 0.7471 | −0.0273 | 0.058* | |
| C9 | 0.4220 (4) | 0.8188 (4) | 0.1024 (3) | 0.0403 (13) | |
| H9 | 0.4504 | 0.8481 | 0.0567 | 0.048* | |
| C10 | 0.4950 (4) | 0.7072 (4) | 0.1233 (3) | 0.0379 (12) | |
| C11 | 0.4592 (5) | 0.6052 (4) | 0.0851 (3) | 0.0508 (15) | |
| H11 | 0.3858 | 0.6039 | 0.0497 | 0.061* | |
| C12 | 0.5286 (5) | 0.5052 (5) | 0.0977 (3) | 0.0560 (15) | |
| H12 | 0.5015 | 0.4371 | 0.0723 | 0.067* | |
| C13 | 0.6382 (5) | 0.5084 (4) | 0.1484 (3) | 0.0474 (14) | |
| C14 | 0.6747 (5) | 0.6063 (5) | 0.1892 (3) | 0.0526 (15) | |
| H14 | 0.7467 | 0.6066 | 0.2258 | 0.063* | |
| C15 | 0.6030 (4) | 0.7050 (5) | 0.1754 (3) | 0.0469 (14) | |
| H15 | 0.6290 | 0.7720 | 0.2024 | 0.056* | |
| C16 | 0.3439 (5) | 0.8482 (4) | 0.3466 (3) | 0.0442 (13) | |
| C17 | 0.2643 (5) | 0.7626 (5) | 0.3627 (3) | 0.0541 (15) | |
| H17 | 0.2386 | 0.7049 | 0.3270 | 0.065* | |
| C18 | 0.2233 (6) | 0.7624 (5) | 0.4310 (4) | 0.0669 (18) | |
| H18 | 0.1689 | 0.7049 | 0.4408 | 0.080* | |
| C19 | 0.2606 (5) | 0.8448 (5) | 0.4849 (4) | 0.0625 (17) | |
| H19 | 0.2332 | 0.8430 | 0.5315 | 0.075* | |
| C20 | 0.3380 (5) | 0.9292 (5) | 0.4697 (3) | 0.0584 (16) | |
| H20 | 0.3625 | 0.9862 | 0.5060 | 0.070* | |
| C21 | 0.3816 (5) | 0.9328 (5) | 0.4016 (3) | 0.0526 (15) | |
| H21 | 0.4356 | 0.9911 | 0.3925 | 0.063* | |
| C22 | 0.1487 (5) | 0.9681 (5) | −0.0949 (3) | 0.0485 (14) | |
| C23 | 0.0411 (6) | 0.9218 (5) | −0.1334 (4) | 0.0694 (19) | |
| H23 | 0.0189 | 0.8469 | −0.1224 | 0.083* | |
| C24 | −0.0353 (6) | 0.9854 (6) | −0.1886 (4) | 0.0719 (19) | |
| H24 | −0.1087 | 0.9525 | −0.2137 | 0.086* | |
| C25 | −0.0056 (6) | 1.0951 (5) | −0.2070 (4) | 0.0646 (17) | |
| H25 | −0.0576 | 1.1376 | −0.2439 | 0.078* | |
| C26 | 0.1045 (6) | 1.1405 (5) | −0.1688 (4) | 0.0619 (17) | |
| H26 | 0.1276 | 1.2147 | −0.1806 | 0.074* | |
| C27 | 0.1799 (5) | 1.0788 (5) | −0.1142 (3) | 0.0543 (15) | |
| H27 | 0.2536 | 1.1116 | −0.0895 | 0.065* |
| Cl1 | 0.0781 (11) | 0.0616 (10) | 0.0802 (14) | 0.0182 (8) | 0.0080 (10) | 0.0048 (9) |
| O1 | 0.063 (2) | 0.047 (2) | 0.054 (3) | −0.0074 (18) | 0.020 (2) | −0.006 (2) |
| O2 | 0.068 (3) | 0.067 (3) | 0.057 (3) | −0.015 (2) | 0.027 (2) | 0.007 (2) |
| O3 | 0.039 (2) | 0.059 (2) | 0.049 (2) | −0.0080 (16) | 0.0042 (19) | 0.011 (2) |
| O4 | 0.055 (2) | 0.059 (2) | 0.037 (2) | −0.0088 (17) | 0.0071 (19) | 0.0074 (19) |
| N1 | 0.067 (3) | 0.047 (3) | 0.041 (3) | −0.008 (2) | 0.020 (3) | −0.007 (2) |
| N2 | 0.039 (2) | 0.063 (3) | 0.051 (3) | −0.001 (2) | 0.002 (2) | 0.018 (3) |
| C1 | 0.043 (3) | 0.047 (3) | 0.059 (4) | −0.001 (2) | 0.016 (3) | 0.001 (3) |
| C2 | 0.026 (2) | 0.056 (3) | 0.033 (3) | −0.002 (2) | 0.003 (2) | −0.003 (3) |
| C3 | 0.035 (3) | 0.041 (3) | 0.041 (3) | −0.001 (2) | 0.007 (3) | 0.001 (3) |
| C4 | 0.050 (3) | 0.052 (3) | 0.037 (3) | 0.000 (3) | 0.013 (3) | −0.002 (3) |
| C5 | 0.034 (3) | 0.048 (3) | 0.040 (3) | −0.004 (2) | 0.005 (3) | −0.004 (3) |
| C6 | 0.033 (2) | 0.046 (3) | 0.036 (3) | −0.003 (2) | 0.005 (2) | −0.003 (3) |
| C7 | 0.042 (3) | 0.045 (3) | 0.038 (3) | −0.004 (2) | 0.008 (3) | −0.002 (3) |
| C8 | 0.040 (3) | 0.058 (3) | 0.045 (4) | −0.006 (2) | 0.003 (3) | 0.007 (3) |
| C9 | 0.033 (3) | 0.051 (3) | 0.037 (3) | −0.007 (2) | 0.006 (2) | −0.001 (3) |
| C10 | 0.039 (3) | 0.045 (3) | 0.029 (3) | −0.002 (2) | 0.005 (2) | −0.007 (3) |
| C11 | 0.041 (3) | 0.065 (4) | 0.041 (4) | −0.004 (3) | −0.009 (3) | −0.010 (3) |
| C12 | 0.054 (3) | 0.058 (4) | 0.054 (4) | 0.001 (3) | 0.003 (3) | −0.011 (3) |
| C13 | 0.048 (3) | 0.045 (3) | 0.049 (4) | 0.002 (2) | 0.008 (3) | 0.000 (3) |
| C14 | 0.041 (3) | 0.069 (4) | 0.044 (4) | −0.002 (3) | −0.005 (3) | −0.001 (3) |
| C15 | 0.042 (3) | 0.051 (3) | 0.047 (4) | −0.004 (3) | 0.004 (3) | −0.009 (3) |
| C16 | 0.051 (3) | 0.050 (3) | 0.032 (3) | 0.005 (3) | 0.009 (3) | 0.003 (3) |
| C17 | 0.058 (3) | 0.064 (4) | 0.041 (4) | −0.015 (3) | 0.011 (3) | −0.004 (3) |
| C18 | 0.070 (4) | 0.077 (4) | 0.058 (5) | −0.013 (3) | 0.023 (4) | −0.002 (4) |
| C19 | 0.064 (4) | 0.083 (4) | 0.041 (4) | 0.005 (3) | 0.010 (3) | 0.008 (4) |
| C20 | 0.071 (4) | 0.064 (4) | 0.039 (4) | 0.007 (3) | 0.005 (3) | −0.004 (3) |
| C21 | 0.061 (4) | 0.056 (3) | 0.040 (4) | −0.009 (3) | 0.007 (3) | −0.005 (3) |
| C22 | 0.051 (3) | 0.054 (3) | 0.039 (3) | 0.001 (3) | 0.004 (3) | 0.005 (3) |
| C23 | 0.065 (4) | 0.063 (4) | 0.068 (5) | −0.020 (3) | −0.020 (4) | 0.014 (4) |
| C24 | 0.060 (4) | 0.087 (5) | 0.061 (5) | −0.016 (3) | −0.013 (4) | 0.009 (4) |
| C25 | 0.060 (4) | 0.072 (4) | 0.058 (4) | 0.014 (3) | 0.002 (3) | 0.010 (4) |
| C26 | 0.070 (4) | 0.055 (4) | 0.061 (4) | 0.002 (3) | 0.012 (4) | 0.007 (3) |
| C27 | 0.051 (3) | 0.060 (4) | 0.051 (4) | 0.000 (3) | 0.004 (3) | −0.001 (3) |
| Cl1—C13 | 1.745 (5) | C11—H11 | 0.9300 |
| O1—C1 | 1.366 (6) | C12—C13 | 1.369 (7) |
| O1—C4 | 1.436 (6) | C12—H12 | 0.9300 |
| O2—C1 | 1.223 (6) | C13—C14 | 1.367 (7) |
| O3—C5 | 1.357 (6) | C14—C15 | 1.383 (7) |
| O3—C8 | 1.439 (6) | C14—H14 | 0.9300 |
| O4—C5 | 1.224 (6) | C15—H15 | 0.9300 |
| N1—C3 | 1.345 (6) | C16—C17 | 1.384 (7) |
| N1—C16 | 1.412 (6) | C16—C21 | 1.394 (7) |
| N1—H1 | 0.8600 | C17—C18 | 1.369 (8) |
| N2—C7 | 1.329 (6) | C17—H17 | 0.9300 |
| N2—C22 | 1.410 (6) | C18—C19 | 1.362 (8) |
| N2—H2 | 0.8600 | C18—H18 | 0.9300 |
| C1—C2 | 1.427 (7) | C19—C20 | 1.353 (8) |
| C2—C3 | 1.366 (7) | C19—H19 | 0.9300 |
| C2—C9 | 1.512 (7) | C20—C21 | 1.381 (8) |
| C3—C4 | 1.484 (7) | C20—H20 | 0.9300 |
| C4—H4A | 0.9700 | C21—H21 | 0.9300 |
| C4—H4B | 0.9700 | C22—C23 | 1.365 (7) |
| C5—C6 | 1.436 (7) | C22—C27 | 1.385 (7) |
| C6—C7 | 1.349 (7) | C23—C24 | 1.384 (8) |
| C6—C9 | 1.522 (6) | C23—H23 | 0.9300 |
| C7—C8 | 1.509 (6) | C24—C25 | 1.364 (8) |
| C8—H8A | 0.9700 | C24—H24 | 0.9300 |
| C8—H8B | 0.9700 | C25—C26 | 1.381 (8) |
| C9—C10 | 1.530 (6) | C25—H25 | 0.9300 |
| C9—H9 | 0.9800 | C26—C27 | 1.360 (8) |
| C10—C15 | 1.369 (7) | C26—H26 | 0.9300 |
| C10—C11 | 1.383 (6) | C27—H27 | 0.9300 |
| C11—C12 | 1.381 (7) | ||
| C1—O1—C4 | 108.2 (4) | C10—C11—H11 | 118.8 |
| C5—O3—C8 | 108.8 (4) | C13—C12—C11 | 118.6 (5) |
| C3—N1—C16 | 131.5 (5) | C13—C12—H12 | 120.7 |
| C3—N1—H1 | 114.2 | C11—C12—H12 | 120.7 |
| C16—N1—H1 | 114.2 | C14—C13—C12 | 120.9 (5) |
| C7—N2—C22 | 129.4 (4) | C14—C13—Cl1 | 121.0 (5) |
| C7—N2—H2 | 115.3 | C12—C13—Cl1 | 118.2 (4) |
| C22—N2—H2 | 115.3 | C13—C14—C15 | 119.0 (5) |
| O2—C1—O1 | 120.4 (5) | C13—C14—H14 | 120.5 |
| O2—C1—C2 | 129.0 (5) | C15—C14—H14 | 120.5 |
| O1—C1—C2 | 110.5 (5) | C10—C15—C14 | 122.2 (5) |
| C3—C2—C1 | 107.7 (5) | C10—C15—H15 | 118.9 |
| C3—C2—C9 | 131.7 (5) | C14—C15—H15 | 118.9 |
| C1—C2—C9 | 120.6 (5) | C17—C16—C21 | 118.5 (5) |
| N1—C3—C2 | 127.3 (5) | C17—C16—N1 | 116.8 (5) |
| N1—C3—C4 | 124.2 (5) | C21—C16—N1 | 124.7 (5) |
| C2—C3—C4 | 108.4 (4) | C18—C17—C16 | 120.3 (6) |
| O1—C4—C3 | 105.2 (4) | C18—C17—H17 | 119.8 |
| O1—C4—H4A | 110.7 | C16—C17—H17 | 119.8 |
| C3—C4—H4A | 110.7 | C19—C18—C17 | 121.3 (6) |
| O1—C4—H4B | 110.7 | C19—C18—H18 | 119.4 |
| C3—C4—H4B | 110.7 | C17—C18—H18 | 119.4 |
| H4A—C4—H4B | 108.8 | C20—C19—C18 | 118.9 (6) |
| O4—C5—O3 | 119.6 (4) | C20—C19—H19 | 120.5 |
| O4—C5—C6 | 129.9 (5) | C18—C19—H19 | 120.5 |
| O3—C5—C6 | 110.4 (5) | C19—C20—C21 | 121.8 (6) |
| C7—C6—C5 | 107.9 (4) | C19—C20—H20 | 119.1 |
| C7—C6—C9 | 129.1 (5) | C21—C20—H20 | 119.1 |
| C5—C6—C9 | 123.0 (5) | C20—C21—C16 | 119.2 (5) |
| N2—C7—C6 | 128.4 (5) | C20—C21—H21 | 120.4 |
| N2—C7—C8 | 123.0 (5) | C16—C21—H21 | 120.4 |
| C6—C7—C8 | 108.6 (5) | C23—C22—C27 | 117.9 (5) |
| O3—C8—C7 | 104.2 (4) | C23—C22—N2 | 124.2 (5) |
| O3—C8—H8A | 110.9 | C27—C22—N2 | 118.0 (5) |
| C7—C8—H8A | 110.9 | C22—C23—C24 | 120.6 (6) |
| O3—C8—H8B | 110.9 | C22—C23—H23 | 119.7 |
| C7—C8—H8B | 110.9 | C24—C23—H23 | 119.7 |
| H8A—C8—H8B | 108.9 | C25—C24—C23 | 121.6 (6) |
| C2—C9—C6 | 113.4 (4) | C25—C24—H24 | 119.2 |
| C2—C9—C10 | 114.5 (4) | C23—C24—H24 | 119.2 |
| C6—C9—C10 | 112.1 (4) | C24—C25—C26 | 117.4 (6) |
| C2—C9—H9 | 105.2 | C24—C25—H25 | 121.3 |
| C6—C9—H9 | 105.2 | C26—C25—H25 | 121.3 |
| C10—C9—H9 | 105.2 | C27—C26—C25 | 121.3 (6) |
| C15—C10—C11 | 116.9 (5) | C27—C26—H26 | 119.3 |
| C15—C10—C9 | 122.2 (4) | C25—C26—H26 | 119.3 |
| C11—C10—C9 | 120.7 (4) | C26—C27—C22 | 121.1 (6) |
| C12—C11—C10 | 122.3 (5) | C26—C27—H27 | 119.4 |
| C12—C11—H11 | 118.8 | C22—C27—H27 | 119.4 |
| C4—O1—C1—O2 | 178.2 (5) | C7—C6—C9—C10 | −133.2 (5) |
| C4—O1—C1—C2 | −0.8 (5) | C5—C6—C9—C10 | 49.9 (6) |
| O2—C1—C2—C3 | −177.5 (5) | C2—C9—C10—C15 | −20.6 (7) |
| O1—C1—C2—C3 | 1.3 (6) | C6—C9—C10—C15 | −151.7 (5) |
| O2—C1—C2—C9 | 1.1 (8) | C2—C9—C10—C11 | 164.8 (4) |
| O1—C1—C2—C9 | 180.0 (4) | C6—C9—C10—C11 | 33.7 (7) |
| C16—N1—C3—C2 | −170.5 (5) | C15—C10—C11—C12 | −0.6 (8) |
| C16—N1—C3—C4 | 8.6 (8) | C9—C10—C11—C12 | 174.3 (5) |
| C1—C2—C3—N1 | 177.9 (5) | C10—C11—C12—C13 | −1.7 (8) |
| C9—C2—C3—N1 | −0.5 (9) | C11—C12—C13—C14 | 4.0 (8) |
| C1—C2—C3—C4 | −1.3 (5) | C11—C12—C13—Cl1 | −176.0 (4) |
| C9—C2—C3—C4 | −179.7 (5) | C12—C13—C14—C15 | −3.9 (8) |
| C1—O1—C4—C3 | 0.0 (5) | Cl1—C13—C14—C15 | 176.1 (4) |
| N1—C3—C4—O1 | −178.4 (4) | C11—C10—C15—C14 | 0.8 (8) |
| C2—C3—C4—O1 | 0.9 (5) | C9—C10—C15—C14 | −174.1 (5) |
| C8—O3—C5—O4 | 176.8 (5) | C13—C14—C15—C10 | 1.5 (8) |
| C8—O3—C5—C6 | −2.7 (5) | C3—N1—C16—C17 | 162.7 (5) |
| O4—C5—C6—C7 | −176.9 (5) | C3—N1—C16—C21 | −17.4 (9) |
| O3—C5—C6—C7 | 2.5 (6) | C21—C16—C17—C18 | 0.6 (8) |
| O4—C5—C6—C9 | 0.5 (8) | N1—C16—C17—C18 | −179.5 (5) |
| O3—C5—C6—C9 | 179.9 (4) | C16—C17—C18—C19 | −0.9 (9) |
| C22—N2—C7—C6 | −169.7 (5) | C17—C18—C19—C20 | 1.1 (9) |
| C22—N2—C7—C8 | 8.8 (9) | C18—C19—C20—C21 | −1.1 (9) |
| C5—C6—C7—N2 | 177.4 (5) | C19—C20—C21—C16 | 0.8 (9) |
| C9—C6—C7—N2 | 0.2 (9) | C17—C16—C21—C20 | −0.6 (8) |
| C5—C6—C7—C8 | −1.2 (6) | N1—C16—C21—C20 | 179.6 (5) |
| C9—C6—C7—C8 | −178.4 (5) | C7—N2—C22—C23 | −37.0 (9) |
| C5—O3—C8—C7 | 1.9 (5) | C7—N2—C22—C27 | 143.6 (6) |
| N2—C7—C8—O3 | −179.0 (5) | C27—C22—C23—C24 | −1.5 (9) |
| C6—C7—C8—O3 | −0.3 (6) | N2—C22—C23—C24 | 179.1 (6) |
| C3—C2—C9—C6 | 65.9 (7) | C22—C23—C24—C25 | 0.7 (10) |
| C1—C2—C9—C6 | −112.3 (5) | C23—C24—C25—C26 | 0.5 (10) |
| C3—C2—C9—C10 | −64.5 (7) | C24—C25—C26—C27 | −0.8 (9) |
| C1—C2—C9—C10 | 117.3 (5) | C25—C26—C27—C22 | −0.1 (9) |
| C7—C6—C9—C2 | 95.1 (7) | C23—C22—C27—C26 | 1.2 (9) |
| C5—C6—C9—C2 | −81.7 (6) | N2—C22—C27—C26 | −179.4 (5) |
| H··· | ||||
| N1—H1···O4 | 0.86 | 2.05 | 2.797 (3) | 145 |
| N2—H2···O2i | 0.86 | 2.09 | 2.907 (3) | 158 |
| C4—H4A···O4ii | 0.97 | 2.24 | 3.206 (3) | 178 |
| C8—H8A···Cg5iii | 0.97 | 2.98 | 3.721 (3) | 134 |
| C8—H8B···Cg4iv | 0.97 | 2.91 | 3.617 (3) | 131 |
| C19—H19···Cg3v | 0.93 | 2.90 | 3.766 (3) | 156 |
Hydrogen-bond geometry (Å, °)
| H⋯ | ||||
|---|---|---|---|---|
| N1—H1⋯O4 | 0.86 | 2.05 | 2.797 (3) | 145 |
| N2—H2⋯O2i | 0.86 | 2.09 | 2.907 (3) | 158 |
| C4—H4 | 0.97 | 2.24 | 3.206 (3) | 178 |
| C8—H8 | 0.97 | 2.98 | 3.721 (3) | 134 |
| C8—H8 | 0.97 | 2.91 | 3.617 (3) | 131 |
| C19—H19⋯ | 0.93 | 2.90 | 3.766 (3) | 156 |
Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) . Cg3, Cg4 and Cg5 are the centroids of the C10–C15, C16–C21 and C22–C27 rings, respectively.