organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoSTRUCTURAL
CHEMISTRY
ISSN: 2053-2296

Hydrogen-bonded chains in isostructural 5-meth­yl-2-(4-methyl­phen­yl)-7,8-di­hydro-6H-cyclo­penta­[g]­pyra­zolo­[1,5-a]pyrimidine, 2-(4-chloro­phen­yl)-5-meth­yl-7,8-di­hydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine and 2-(4-bromo­phen­yl)-5-meth­yl-7,8-di­hydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, and sheets of π-stacked hydrogen-bonded chains in 2-(4-meth­oxy­phen­yl)-5-meth­yl-7,8-di­hydro-6H-cyclo­penta­[g]­pyrazolo[1,5-a]pyrimidine

aGrupo de Investigación de Compuestos Heterocíclicos, Departamento de Química, Universidad de Valle, AA 25360 Cali, Colombia, bDepartamento de Química Inorgánica y Orgánica, Universidad de Jaén, 23071 Jaén, Spain, cDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland
*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 24 May 2005; accepted 25 May 2005; online 22 June 2005)

5-Meth­yl-2-(4-methyl­phen­yl)-7,8-dihydro-6H-cyclo­penta­[g]­pyra­zolo[1,5-a]pyrimidine, C17H17N3, 2-(4-chloro­phen­yl)-5-meth­yl-7,8-dihydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimi­dine, C16H14ClN3, and 2-(4-bromo­phen­yl)-5-meth­yl-7,8-di­hy­dro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, C16H14BrN3, are isostructural; in each compound, the mol­ecules are linked into chains by a single C—H⋯π(arene) hydrogen bond. Mol­ecules of 2-(4-methoxy­phen­yl)-5-meth­yl-7,8-di­hydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, C17H17N3O, are linked by a single C—H⋯N hydrogen bond into chains, which are themselves linked into sheets by a ππ stacking inter­action.

Comment

Pyrazolo[1,5-a]pyrimidines are purine analogues which have shown useful properties as antimetabolites, and which have been of pharmaceutical inter­est because of their antitrypanosomal activity (Novinson et al., 1976[Novinson, T., Bhooshan, B., Okabe, T., Revankar, G. R., Robins, R. K., Senga, K. & Wilson, H. R. (1976). J. Med. Chem. 19, 512-516.]) and their antischistosomal activity (Senga et al., 1981[Senga, K., Novinson, T., Wilson, H. R. & Robins, R. K. (1981). J. Med. Chem. 24, 610-613.]). These inter­esting biological properties have prompted the search for new and efficient procedures of wide generality for the synthesis of pyrazolo[1,5-a]pyrimidine derivatives (Al-Shiekh et al., 2004[Al-Shiekh, M., Salah El-Din, A. M., Hafez, E. & Elnagdi, M. H. (2004). J. Heterocycl. Chem. 41, 647-654.]; Makarov et al., 2005[Makarov, V., Riabova, O., Granik, V. G., Dahse, H.-M., Stelzner, A., Wutzler, P. & Schmidtke, M. (2005). Bioorg. Med. Chem. Lett. 15, 37-39.]). We report here the structures of four cyclo­penta­[g]pyrazolo[1,5-a]pyrimidines, namely 5-meth­yl-2-(4-methyl­phen­yl)-7,8-dihydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, (I)[link], 2-(4-chloro­phen­yl)-5-meth­yl-7,8-dihydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, (II)[link], 2-(4-bromo­phen­yl)-5-meth­yl-7,8-dihydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, (III)[link], and 2-(4-methoxy­phen­yl)-5-meth­yl-7,8-dihydro-6H-cyclo­penta­[g]pyrazolo[1,5-a]pyrimidine, (IV)[link], prepared by solvent-free cyclo­condensation reactions between 5-amino-1H-pyrazole derivatives and 2-acetyl­cyclo­penta­none, induced by microwave irradiation.

[Scheme 1]

Compounds (I)–(III)[link] form isomorphous crystals, and the compounds are isostructural. This fact is consistent with the similar steric requirements of meth­yl, chloro and bromo substituents, as reflected, for example, in the similar unit-cell dimensions of (I)–(III)[link].

The corresponding bond lengths within the heterobicyclic fragments in compounds (I)–(IV)[link] (Figs. 1[link]–4[link][link][link]) are very similar (Table 1[link]), but the patterns of these bond distances show some inter­esting properties. In each of (I)–(IV)[link], the N1—C2 bond, which is formally a double bond, is not significantly shorter than the C3A—N4 and C8A—N8B bonds, both of which are formally single bonds; at the same time, the cross-ring bonds C3A—N8B are by far the longest C—N bond in any mol­ecule. These observations, together with the clear bond fixation in the pyrimidine ring, suggest that the ten π electrons of the pyrazolopyrimidine units are not fully delocalized around the periphery, but instead adopt a more characteristic arrangement, reminiscent of that in naphthalene.

In all of these compounds, the five-membered carbocyclic ring has an envelope conformation, with the fold across the line C6⋯C8; the total puckering amplitude Q (Cremer & Pople, 1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]) is larger in (III)[link] [0.231 (4) Å] than in any of (I)[link] [0.111 (3) Å], (II)[link] [0.159 (3) Å] or (IV)[link] [0.095 (2) Å], but in each case the ring-puckering parameter φ2 [257.1 (14)° in (I)[link], 255.0 (10)° in (II)[link], 73.3 (8)° in (III)[link] and 73.6 (8)° in (IV)[link] for the atom sequence C5A—C6—C7—C8—C8A] is very close to the ideal value of 36n° (Evans & Boeyens, 1989[Evans, D. G. & Boeyens, J. C. A. (1989). Acta Cryst. B45, 581-590.]), with n = 7 in (I)[link] and (II)[link], and n = 2 in (III)[link] and (IV)[link]. The 4-substituted C21–C26 ar­yl ring is nearly coplanar with the heterobicyclic ring system in each of (I)–(IV)[link]; thus, the dihedral angles between the ar­yl ring and the mean plane of the pyrazolopyrimidine ring system are 12.0 (2)° in (I)[link], 14.5 (2)° in (II)[link], 14.2 (2)° in (III)[link] and 3.6 (2)° in (IV)[link]. In compound (IV)[link], meth­oxy atom C241 is nearly coplanar with the ar­yl ring and, consistent with this, the exocyclic C—C—O angles at atom C24 show the usual deviations from 120° (Table 1[link]).

Despite the strong similarities between compounds (I)–(IV)[link] in terms both of their overall constitutions and of their intra­molecular geometries and conformations, the pattern of supramolecular aggregation in compound (IV)[link] is very different from that in the isostructural trio (I)–(III)[link], both from the point of view of the direction-specific inter­actions present and in terms of their overall supramolecular structures.

In each of compounds (I)–(III)[link], the mol­ecules are linked into chains by a single C—H⋯π(arene) hydrogen bond (Table 2[link]); atom C6 in the mol­ecule at (x, y, z) acts as a donor, via atom H6A, to the pyrazole ring in the mol­ecule at (x, −1 + y, z), so generating by translation a chain running parallel to the [010] direction (Fig. 5[link]). It should be noted that C—H⋯N and, in (II)[link] and (III)[link], C—H⋯halogen hydrogen bonds, as well as aromatic ππ stacking inter­actions, are all absent from the structures of (I)–(III).

By contrast, in compound (IV)[link], the mol­ecules are linked into chains by a C—H⋯N hydrogen bond (Table 2[link]), and these chains are themselves linked into sheets by a ππ stacking inter­action. Ar­yl atom C22 in the mol­ecule at (x, y, z) acts as a hydrogen-bond donor to pyrimidine atom N4 in the mol­ecule at (1 − x, −[{1\over 2}] + y, [{1\over 2}]z), so forming a C(7) chain running parallel to the [010] direction and generated by the 21 screw axis along ([{1\over 2}], y, [{1\over 4}]) (Fig. 6[link]). The ππ stacking inter­action involves the fused heterocyclic rings of the mol­ecules at (x, y, z) and (1 − x, 2 − y, −z), where the inter­planar spacing is 3.504 (2) Å; the ring-centroid separation of the pyrazole and pyrimidine rings, respectively, is 3.577 (2) Å, corresponding to a ring-centroid offset of 0.719 (2) Å; the corresponding separation of the pyrimidine centroids is 3.799 (2) Å, with a centroid offset of 1.489 (2) Å. These two mol­ecules lie in the C(7) chains along ([{1\over 2}], y, [1\over4]) and ([{1\over 2}], y, −[1\over4]), respectively, and propagation by the space group of this stacking inter­action generates a sheet lying parallel to (100) (Fig. 7[link]).

It is striking that, although the substituents in the ar­yl rings, viz. 4-meth­yl in (I)[link], 4-chloro in (II)[link], 4-bromo in (III)[link] and 4-meth­oxy in (IV)[link], play no direct role whatever in the supramolecular aggregation, nonetheless the types of direction-specific inter­molecular inter­action apparent in the crystal structures of (I)–(III)[link] are entirely different from those apparent in the structure of (IV)[link]. The influence of these remote substituents on the supramolecular structures thus appears to be indirect and rather subtle, but real nonetheless; such subtle influences necessarily hinder the effective prediction of such structures.

[Figure 1]
Figure 1
The mol­ecule of (I)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2]
Figure 2
The mol­ecule of (II)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3]
Figure 3
The mol­ecule of (III)[link], showing the atom-labelling scheme. For clarity, only the major orientation of the disordered CH2 group is shown. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 4]
Figure 4
The mol­ecule of (IV)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 5]
Figure 5
Part of the crystal structure of (I)[link], showing the formation via C—H⋯π(arene) hydrogen bonds (dashed lines) of a chain along [010]. For clarity, H atoms bonded to those C atoms that are not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions (x, −1 + y, z) and (x, 1 + y, z), respectively. The [010] chains in (II)[link] and (III)[link] are essentially identical to that in (I)[link].
[Figure 6]
Figure 6
Part of the crystal structure of (IV)[link], showing the formation via C—H⋯N hydrogen bonds (dashed lines) of a C(7) chain along [010]. For clarity, H atoms not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions (1 − x, −[{1\over 2}] + y, [{1\over 2}] − z) and (1 − x, [{1\over 2}] + y, [{1\over 2}] − z), respectively.
[Figure 7]
Figure 7
A stereoview of part of the crystal structure of compound (IV)[link], showing the formation of a (100) sheet of π-stacked [010] chains. For clarity, H atoms not involved in the motif shown have been omitted.

Experimental

Equimolar mixtures of the appropriate 5-amino-3-ar­yl-1H-pyrazole (2.6 mmol) [where ar­yl is 4-methyl­phen­yl for (I)[link], 4-chloro­phen­yl for (II)[link], 4-bromo­phen­yl for (III)[link] and 4-methoxy­phen­yl for (IV)] and 2-acetyl­cyclo­penta­none (2.6 mmol) were placed in open Pyrex glass vessels and irradiated in a domestic microwave oven for 1.5–2 min at 600 W. The product mixtures were extracted with ethanol and, after removal of the solvent, the resulting solids were recrystallized from dimethyl­formamide to give crystals of (I)–(IV)[link] suitable for single-crystal X-ray diffraction. For (I)[link], m.p. 512–513 K, yield 80%; MS (30 eV) m/z (%): 263 (100, M+), 248 (4). For (II)[link], m.p. 496–497 K, yield 83%; MS (30 eV) m/z (%): 285/283 (35/100, M+), 268 (3), 241 (2). For (III)[link], m.p. 496–497 K, yield 83%; MS (30 eV) m/z (%): 329/327 (97/100, M+), 312 (3). For (IV)[link], m.p. 497–498 K, yield 85%; MS (30 eV) m/z (%): 279 (100, M+), 264 (27), 236 (7).

Compound (I)[link]

Crystal data
  • C17H17N3

  • Mr = 263.34

  • Monoclinic, P 21 /c

  • a = 13.2882 (7) Å

  • b = 6.8383 (4) Å

  • c = 15.1947 (8) Å

  • β = 104.018 (3)°

  • V = 1339.60 (13) Å3

  • Z = 4

  • Dx = 1.306 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3076 reflections

  • θ = 3.2–27.5°

  • μ = 0.08 mm−1

  • T = 120 (2) K

  • Needle, colourless

  • 0.52 × 0.08 × 0.04 mm

Data collection
  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.955, Tmax = 0.997

  • 13947 measured reflections

  • 3076 independent reflections

  • 1640 reflections with I > 2σ(I)

  • Rint = 0.085

  • θmax = 27.5°

  • h = −17 → 16

  • k = −8 → 8

  • l = −19 → 19

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.175

  • S = 1.01

  • 3076 reflections

  • 183 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0891P)2 + 0.0582P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.35 e Å−3

  • Δρmin = −0.29 e Å−3

Compound (II)[link]

Crystal data
  • C16H14ClN3

  • Mr = 283.75

  • Monoclinic, P 21 /c

  • a = 13.6800 (11) Å

  • b = 6.6669 (6) Å

  • c = 15.2010 (16) Å

  • β = 106.980 (6)°

  • V = 1325.9 (2) Å3

  • Z = 4

  • Dx = 1.421 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3040 reflections

  • θ = 3.4–27.6°

  • μ = 0.28 mm−1

  • T = 120 (2) K

  • Plate, colourless

  • 0.34 × 0.18 × 0.03 mm

Data collection
  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.922, Tmax = 0.992

  • 14750 measured reflections

  • 3040 independent reflections

  • 2060 reflections with I > 2σ(I)

  • Rint = 0.072

  • θmax = 27.6°

  • h = −16 → 17

  • k = −8 → 8

  • l = −17 → 19

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.141

  • S = 1.03

  • 3040 reflections

  • 182 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0726P)2 + 0.3419P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.49 e Å−3

Compound (III)[link]

Crystal data
  • C16H14BrN3

  • Mr = 328.21

  • Monoclinic, P 21 /c

  • a = 13.5387 (6) Å

  • b = 6.8551 (2) Å

  • c = 15.2767 (7) Å

  • β = 105.708 (2)°

  • V = 1364.87 (10) Å3

  • Z = 4

  • Dx = 1.597 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3125 reflections

  • θ = 3.3–27.5°

  • μ = 3.00 mm−1

  • T = 120 (2) K

  • Plate, colourless

  • 0.66 × 0.20 × 0.02 mm

Data collection
  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.242, Tmax = 0.942

  • 18357 measured reflections

  • 3125 independent reflections

  • 2438 reflections with I > 2σ(I)

  • Rint = 0.069

  • θmax = 27.5°

  • h = −17 → 17

  • k = −8 → 8

  • l = −19 → 19

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.096

  • S = 1.05

  • 3125 reflections

  • 186 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0473P)2 + 0.618P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.68 e Å−3

Compound (IV)[link]

Crystal data
  • C17H17N3O

  • Mr = 279.34

  • Monoclinic, P 21 /c

  • a = 9.4691 (3) Å

  • b = 8.1711 (2) Å

  • c = 18.0278 (6) Å

  • β = 95.3430 (14)°

  • V = 1388.80 (7) Å3

  • Z = 4

  • Dx = 1.336 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3192 reflections

  • θ = 3.0–27.5°

  • μ = 0.09 mm−1

  • T = 120 (2) K

  • Block, colourless

  • 0.40 × 0.38 × 0.30 mm

Data collection
  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.956, Tmax = 0.975

  • 16180 measured reflections

  • 3192 independent reflections

  • 2520 reflections with I > 2σ(I)

  • Rint = 0.033

  • θmax = 27.5°

  • h = −12 → 12

  • k = −9 → 10

  • l = −18 → 23

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.126

  • S = 1.06

  • 3192 reflections

  • 193 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0744P)2 + 0.2357P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.25 e Å−3

  • Extinction correction: SHELXL97

  • Extinction coefficient: 0.028 (5)

Table 1
Selected geometric parameters (Å, °) for compounds (I)–(IV)

  (I) (II) (III) (IV)
N1—C2 1.348 (3) 1.349 (2) 1.351 (3) 1.3522 (16)
C2—C3 1.400 (3) 1.407 (3) 1.408 (4) 1.4047 (18)
C3—C3A 1.380 (3) 1.380 (3) 1.381 (4) 1.3858 (18)
C3A—N4 1.356 (3) 1.358 (3) 1.361 (3) 1.3622 (16)
N4—C5 1.333 (3) 1.328 (3) 1.335 (3) 1.3255 (17)
C5—C5A 1.418 (3) 1.419 (3) 1.417 (4) 1.4202 (18)
C5A—C8A 1.358 (3) 1.360 (3) 1.362 (4) 1.3614 (18)
C8A—N8B 1.354 (3) 1.345 (3) 1.353 (3) 1.3587 (16)
N8B—N1 1.357 (3) 1.355 (3) 1.355 (3) 1.3592 (14)
C3A—N8B 1.403 (3) 1.401 (3) 1.395 (3) 1.3928 (15)
C23—C24—O24       124.80 (12)
C25—C24—O24       115.26 (11)
C24—O24—C241       117.88 (10)
N1—C2—C21—C22 −168.1 (2) −166.2 (2) −166.4 (2) 176.30 (11)
C23—C24—O24—C241       3.40 (18)

Table 2
Hydrogen bonds and short intramolecular contacts (Å, °) for compounds (I)–(IV)

Cg is the centroid of the N1/C2/C3/C3A/N8B ring.

Compound D—H⋯A D—H H⋯A D⋯A D—H⋯A
(I) C6—H6ACgi 0.99 2.94 3.902 (3) 163
(II) C6—H6ACgi 0.99 2.87 3.820 (3) 160
(III) C6—H6ACgi 0.99 2.99 3.942 (3) 161
(IV) C22—H22⋯N4ii 0.95 2.54 3.436 (2) 156
Symmetry codes: (i) x, -1 + y, z; (ii) [1 - x, -{1\over2} + y, {1\over2} - z].

For each of (I)–(IV), the space group P21/c was uniquely assigned from the systematic absences. All H atoms were located from difference maps in fully ordered sites; they were then treated as riding atoms, with C—H distances of 0.95 (aromatic), 0.98 (meth­yl) or 0.99 Å (CH2), and with Uiso(H) values of 1.2Ueq(C), or 1.5Ueq(C) for the meth­yl groups. For compounds (I)[link] and (II)[link], although not for (IV)[link], the displacement parameters for atom C7 were somewhat higher than those of neighbouring C atoms, and were consistent with an enhanced vibrational amplitude approximately normal to the C6–C8 plane and tangential to the envelope fold. For compound (III)[link], it was necessary to model this atom and its associated H atoms over two sets of sites, with refined occupancies of 0.853 (17) and 0.147 (17). The crystals of compound (III)[link] are very fragile, and attempts to cut small fragments from larger crystals always resulted in shattering.

For all compounds, data collection: COLLECT (Hooft, 1999[Hooft, R. W. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]) for (I), (II) and (III), and OSCAIL (McArdle, 2003[McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland.]) and SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]) for (IV); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999[Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.]).

Supporting information


Comment top

Pyrazolo[1,5-a]pyrimidines are purine analogues which have shown useful properties as antimetabolites, and which have been of pharmaceutical interest because of their antitrypanosomal activity (Novinson et al., 1976) and their antischistosomal activity (Senga et al., 1981). These interesting biological properties have prompted the search for new and efficient procedures of wide generality for the synthesis of pyrazolo[1,5-a]pyrimidine derivatives (Al-Shiekh et al., 2004; Makarov et al., 2005). We report here the structures of four cyclopenta[e]pyrazolo[1,5-a]pyrimidines, namely 5-methyl-2-(4-methylphenyl)-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine, (I), 2-(4-chlorophenyl)-5-methyl-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine, (II), 2-(4-bromophenyl)-5-methyl-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine, (III), and 2-(4-methoxyphenyl)-5-methyl-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine, (IV), prepared by solvent-free cyclocondensation reactions between 5-amino-1H-pyrazole derivatives and 2-acetylcyclopentanone, induced by microwave irradiation.

Compounds (I)–(III) form isomorphous crystals, and the compounds are isostructural, consistent with the similar steric requirements of methyl, chloro and bromo substituents, as reflected for example in the similar unit-cell dimensions of (I)–(III).

The corresponding bond lengths within the heterobicyclic fragments in compounds (I)–(IV) (Figs. 1–4) are very similar (Table 1), but the patterns of these bond distances show some interesting properties. In each of (I)–(IV), the N1—C2 bond, which is formally a double bond, is not significantly shorter than the C3A—N4 and C8A—N8B bonds, both of which are formally single bonds; at the same time the cross-ring bonds C3A—N8B are by far the longest C—N bond in either molecule. These observations, together with the clear bond-fixation in the pyrimidine ring, suggest that the ten π electrons of the pyrazolopyrimidine units are not fully delocalized around the periphery, but instead adopt a more characteristic arrangement, reminiscent of that in naphthalene.

In all of these compounds, the five-membered carbocyclic ring has an envelope conformation, with the fold across the line C6···C8; the total puckering amplitude Q (Cremer & Pople, 1975) is rather larger in (III) [0.231 (4) Å] than in any of (I) [0.111 (3) Å], (II) [0.159 (3) Å] or (IV) [0.095 (2) Å], but in each case the ring-puckering parameter ϕ2 [257.1 (14)° in (I), 255.0 (10)° in (II), 73.3 (8)° in (III) and 73.6 (8)° in (IV) for the atom sequence C5A, C6, C7, C8, C8A] is very close to the ideal value of 36n° (Evans & Boeyens, 1989), with n = 7 in (I) and (II), and n = 2 in (III) and (IV). The 4-substituted C21–C26 aryl ring is nearly coplanar with the heterobicyclic ring in each of (I)–(IV); thus the dihedral angles between the aryl ring and the mean plane of the pyrazolopyrimidine ring are 12.0 (2)° in (I), 14.5 (2)° in (II), 14.2 (2)° in (III) and 3.6 (2)° in (III). In compound (IV) the methoxy atom C241 is nearly coplanar with the aryl ring and, consistent with this, the exocyclic C—C—O angles at C24 show the usual deviations from 120° (Table 1).

Despite the strong similarities between compounds (I)–(IV) in terms both of their overall constitutions and of their intramolecular geometries and conformations, the pattern of supramolecular aggregation in compound (IV) is very different from that in the isostructural trio (I)–(III), both from the point of view of the direction-specific interactions present and in terms of their overall supramolecular structures.

In each of compounds (I)–(III), the molecules are linked into chains by a single C—H···π(arene) hydrogen bond (Table 2): atom C6 in the molecule at (x, y, z) acts as a donor, via atom H6A, to the pyrazole ring in the molecule at (x, −1 + y, z), so generating by translation a chain running parallel to the [010] direction (Fig. 5). It should be noted that C—H···N and, in (II) and (III), C—H···halogen hydrogen bonds, and aromatic ππ stacking interactions, are all absent from the structures of (I)–(III).

By contrast, in compound (IV), the molecules are linked into chains by a C—H···N hydrogen bond (Table 2), and these chains are themselves linked into sheets by a ππ stacking interaction. Aryl atom C22 in the molecule at (x, y, z) acts as a hydrogen-bond donor to pyrimidine atom N4 in the molecule at (1 − x, −1/2 + y, 1/2 − z), so forming a C(7) chain running parallel to the [010] direction and generated by the 21 screw axis along (1/2, y, 1/4) (Fig. 6). The ππ stacking interaction involves the fused heterocyclic rings of the molecules at (x, y, z) and (1 − x, 2 − y, −z), where the interplanar spacing is 3.504 (2) Å; the ring-centroid separation of the pyrazole and pyrimidine rings, respectively, is 3.577 (2) Å, corresponding to a ring-centroid offset of 0.719 (2) Å; the corresponding separation of the pyrimidine centroids is 3.799 (2) Å, with a centroid offset of 1.489 (2) Å. These two molecules lie in the C(7) chains along (1/2, y,1/4) and (1/2, y, −0.25), respectively, and propagation by the space group of this stacking interaction generates a sheet lying parallel to (100) (Fig. 7).

It is striking to that, although the substituents in the aryl rings, viz. 4-methyl in (I), 4-chloro in (II), 4-bromo in (III) and 4-methoxy in (IV), play no direct role whatever in the supramolecular aggregation, nonetheless the types of direction-specific intermolecular interaction apparent in the crystal structures of (I)–(III) are entirely different from those apparent in the structure of (IV). The influence of these remote substituents on the supramolecular structures thus appears to be indirect and rather subtle, but real nonetheless; such subtle influences necessarily hinder the effective prediction of such structures.

Experimental top

Equimolar mixtures of the appropriate 5-amino-3-aryl-1H-pyrazole (2.6 mmol) [where aryl is 4-methylphenyl for (I), 4-chlorophenyl for (II), 4-bromophenyl for (III) and 4-methoxyphenyl for (IV)] and 2-acetylcyclopentanone (2.6 mmol) were placed in open Pyrex-glass vessels and irradiated in a domestic microwave oven for 1.5–2 min at 600 W. The product mixtures were extracted with ethanol, and after removal of the solvent the resulting solids were recrystallized from dimethylformamide to give crystals of (I)–(IV) suitable for single-crystal X-ray diffraction. For (I), m.p. 512–513 K, yield 80%; MS (30 eV) m/z (%): 263 (100, M+), 248 (4). For (II), m.p. 496–497 K, yield 83%; MS: (30 eV) m/z (%): 285/283 (35/100, M+), 268 (3), 241 (2). For (III), m.p. 496–497 K, yield 83%; MS: (30 eV) m/z (%): 329/327 (97/100, M+), 312 (3). For (IV), m.p. 497–498 K, yield 85%; MS: (30 eV) m/z (%): 279 (100, M+), 264 (27), 236 (7).

Refinement top

For each of (I)–(IV), the space group P21/c was uniquely assigned from the systematic absences. All H atoms were located from difference maps in fully ordered sites; they were then treated as riding atoms, with C—H distances of 0.95 Å (aromatic), 0.98 Å (methyl) or 0.99 Å (CH2), and with Uiso(H) values of 1.2Ueq(C), or 1.5Ueq(C) for the methyl groups. For compounds (I) and (II), although not for (IV), the displacement parameters for atom C7 were somewhat higher than those of neighbouring C atoms, and were consistent with an enhanced vibrational amplitude approximately normal to the C6–C8 plane and tangential to the envelope fold. For compound (III), it was necessary to model this atom and its associated H atoms over two sets of sites, with refined occupancies of 0.853 (17) and 0.147 (17), respectively. The crystals of compound (III) are very fragile, and attempts to cut small fragments from larger crystals always resulted in shattering.

Computing details top

For all compounds, data collection: COLLECT (Hooft, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT. Program(s) used to solve structure: WinGX (Farrugia, 1999) and SIR92 (Altomare et al., 1993) for (I), (II), (III); OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997) for (IV). Program(s) used to refine structure: OSCAIL (McArdle, 2003) and SHELXL97 (Sheldrick, 1997) for (I), (II), (III); OSCAIL and SHELXL97 (Sheldrick, 1997) for (IV). For all compounds, molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

Figures top
[Figure 1] Fig. 1. The molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The molecule of (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3] Fig. 3. The molecule of (III), showing the atom-labelling scheme. For clarity, only the major orientation of the disordered CH2 group is shown. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 4] Fig. 4. The molecule of (IV), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 5] Fig. 5. Part of the crystal structure of (I), showing the formation by the C—H···π(arene) hydrogen bond of a chain along [010]. For clarity, H atoms bonded to those C atoms that are not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions (x, −1 + y, z) and (x, 1 + y, z), respectively. The [010] chains in (II) and (III) are essentially identical to that in (I).
[Figure 6] Fig. 6. Part of the crystal structure of (IV), showing the formation by the C—H···N hydrogen bond of a C(7) chain along [010]. For clarity, H atoms not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions (1 − x, −1/2 + y, 1/2 − z) and (1 − x, 1/2 + y, 1/2 − z), respectively.
[Figure 7] Fig. 7. A stereoview of part of the crystal structure of compound (IV), showing the formation of a (100) sheet of π-stacked [010] chains. For clarity, H atoms not involved in the motif shown have been omitted.
(I) 5-methyl-2-(4-methylphenyl)-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine top
Crystal data top
C17H17N3F(000) = 560
Mr = 263.34Dx = 1.306 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3076 reflections
a = 13.2882 (7) Åθ = 3.2–27.5°
b = 6.8383 (4) ŵ = 0.08 mm1
c = 15.1947 (8) ÅT = 120 K
β = 104.018 (3)°Needle, colourless
V = 1339.60 (13) Å30.52 × 0.08 × 0.04 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
3076 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode1640 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.085
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.2°
ϕ and ω scansh = 1716
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 88
Tmin = 0.955, Tmax = 0.997l = 1919
13947 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)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.175H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0891P)2 + 0.0582P]
where P = (Fo2 + 2Fc2)/3
3076 reflections(Δ/σ)max < 0.001
183 parametersΔρmax = 0.35 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C17H17N3V = 1339.60 (13) Å3
Mr = 263.34Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.2882 (7) ŵ = 0.08 mm1
b = 6.8383 (4) ÅT = 120 K
c = 15.1947 (8) Å0.52 × 0.08 × 0.04 mm
β = 104.018 (3)°
Data collection top
Nonius KappaCCD
diffractometer
3076 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
1640 reflections with I > 2σ(I)
Tmin = 0.955, Tmax = 0.997Rint = 0.085
13947 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0640 restraints
wR(F2) = 0.175H-atom parameters constrained
S = 1.01Δρmax = 0.35 e Å3
3076 reflectionsΔρmin = 0.29 e Å3
183 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.28324 (14)0.4477 (3)0.19324 (13)0.0258 (5)
N40.04482 (14)0.1982 (3)0.10167 (13)0.0279 (5)
N8B0.21206 (14)0.3036 (3)0.18910 (12)0.0240 (5)
C20.23925 (17)0.5664 (3)0.12375 (15)0.0238 (6)
C30.14141 (18)0.5009 (4)0.07606 (16)0.0265 (6)
C3A0.12370 (17)0.3295 (3)0.11783 (16)0.0258 (6)
C50.05294 (17)0.0436 (4)0.15636 (16)0.0270 (6)
C5A0.14031 (18)0.0171 (4)0.23026 (15)0.0255 (6)
C60.16504 (19)0.1433 (4)0.30027 (17)0.0329 (6)
C70.2658 (2)0.0766 (5)0.3649 (2)0.0763 (13)
C80.30840 (19)0.0996 (4)0.32186 (17)0.0333 (6)
C8A0.21968 (17)0.1475 (3)0.24522 (15)0.0249 (6)
C210.29531 (17)0.7434 (3)0.10803 (14)0.0233 (6)
C220.24563 (18)0.8880 (3)0.04843 (16)0.0265 (6)
C230.29724 (18)1.0569 (3)0.03507 (16)0.0284 (6)
C240.40046 (18)1.0871 (3)0.07952 (16)0.0265 (6)
C250.45066 (18)0.9414 (4)0.13829 (16)0.0285 (6)
C260.39874 (18)0.7730 (4)0.15188 (15)0.0277 (6)
C510.03292 (19)0.1036 (4)0.13818 (18)0.0364 (7)
C2410.4567 (2)1.2719 (4)0.06545 (17)0.0352 (7)
H30.09640.56190.02530.032*
H6A0.17460.27000.27180.040*
H6B0.10900.15710.33250.040*
H7A0.31700.18450.37540.092*
H7B0.25270.03850.42400.092*
H8A0.32570.21000.36500.040*
H8B0.37050.06340.30040.040*
H220.17530.87030.01650.032*
H230.26141.15420.00530.034*
H24A0.49951.31690.12380.053*
H24B0.40601.37330.03950.053*
H24C0.50111.24550.02390.053*
H250.52130.95800.16930.034*
H260.43460.67550.19200.033*
H51A0.09030.05580.16240.055*
H51B0.00730.22760.16760.055*
H51C0.05740.12400.07260.055*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0264 (11)0.0235 (11)0.0275 (11)0.0008 (9)0.0069 (9)0.0004 (9)
C20.0257 (13)0.0254 (13)0.0223 (12)0.0035 (11)0.0093 (11)0.0003 (11)
C210.0263 (13)0.0223 (13)0.0220 (12)0.0010 (10)0.0073 (10)0.0025 (10)
C260.0275 (14)0.0282 (14)0.0251 (13)0.0014 (11)0.0018 (11)0.0009 (11)
C250.0233 (13)0.0321 (15)0.0296 (13)0.0003 (11)0.0053 (11)0.0072 (12)
C240.0288 (14)0.0258 (13)0.0267 (13)0.0022 (11)0.0100 (11)0.0080 (11)
C2410.0365 (15)0.0335 (15)0.0366 (15)0.0075 (13)0.0110 (12)0.0068 (13)
C230.0305 (14)0.0264 (14)0.0283 (13)0.0005 (11)0.0073 (11)0.0012 (11)
C220.0235 (13)0.0270 (13)0.0292 (13)0.0014 (11)0.0066 (11)0.0023 (11)
C30.0251 (13)0.0272 (13)0.0254 (12)0.0011 (11)0.0024 (11)0.0029 (11)
C3A0.0241 (13)0.0272 (14)0.0264 (13)0.0026 (11)0.0065 (11)0.0005 (11)
N40.0242 (11)0.0271 (12)0.0312 (11)0.0019 (9)0.0046 (9)0.0030 (10)
C50.0248 (14)0.0273 (14)0.0304 (14)0.0026 (11)0.0097 (11)0.0002 (12)
C510.0356 (15)0.0325 (15)0.0410 (16)0.0017 (12)0.0089 (12)0.0063 (13)
C5A0.0263 (13)0.0261 (13)0.0268 (13)0.0068 (11)0.0114 (11)0.0026 (11)
C60.0375 (15)0.0294 (14)0.0355 (15)0.0033 (12)0.0159 (12)0.0057 (12)
C70.0433 (19)0.094 (3)0.079 (3)0.0200 (19)0.0105 (18)0.055 (2)
C80.0299 (14)0.0386 (16)0.0306 (14)0.0023 (12)0.0055 (11)0.0052 (12)
C8A0.0252 (13)0.0280 (13)0.0236 (12)0.0053 (11)0.0098 (10)0.0029 (11)
N8B0.0232 (11)0.0237 (11)0.0246 (10)0.0001 (9)0.0046 (9)0.0015 (9)
Geometric parameters (Å, º) top
N1—C21.348 (3)C3A—N41.356 (3)
N1—N8B1.357 (3)C3A—N8B1.403 (3)
C2—C31.400 (3)N4—C51.333 (3)
C2—C211.471 (3)C5—C5A1.418 (3)
C21—C261.389 (3)C5—C511.497 (3)
C21—C221.395 (3)C51—H51A0.98
C26—C251.383 (3)C51—H51B0.98
C26—H260.95C51—H51C0.98
C25—C241.395 (3)C5A—C8A1.358 (3)
C25—H250.95C5A—C61.508 (3)
C24—C231.390 (3)C6—C71.526 (4)
C24—C2411.509 (3)C6—H6A0.99
C241—H24A0.98C6—H6B0.99
C241—H24B0.98C7—C81.542 (4)
C241—H24C0.98C7—H7A0.99
C23—C221.383 (3)C7—H7B0.99
C23—H230.95C8—C8A1.479 (3)
C22—H220.95C8—H8A0.99
C3—C3A1.380 (3)C8—H8B0.99
C3—H30.95C8A—N8B1.354 (3)
C2—N1—N8B103.65 (18)N4—C5—C51118.4 (2)
N1—C2—C3112.6 (2)C5A—C5—C51120.1 (2)
N1—C2—C21118.8 (2)C5—C51—H51A109.5
C3—C2—C21128.5 (2)C5—C51—H51B109.5
C26—C21—C22117.8 (2)H51A—C51—H51B109.5
C26—C21—C2121.5 (2)C5—C51—H51C109.5
C22—C21—C2120.7 (2)H51A—C51—H51C109.5
C25—C26—C21121.4 (2)H51B—C51—H51C109.5
C25—C26—H26119.3C8A—C5A—C5120.2 (2)
C21—C26—H26119.3C8A—C5A—C6109.4 (2)
C26—C25—C24120.8 (2)C5—C5A—C6130.4 (2)
C26—C25—H25119.6C5A—C6—C7104.1 (2)
C24—C25—H25119.6C5A—C6—H6A110.9
C23—C24—C25117.9 (2)C7—C6—H6A110.9
C23—C24—C241121.3 (2)C5A—C6—H6B110.9
C25—C24—C241120.8 (2)C7—C6—H6B110.9
C24—C241—H24A109.5H6A—C6—H6B109.0
C24—C241—H24B109.5C6—C7—C8108.4 (2)
H24A—C241—H24B109.5C6—C7—H7A110.0
C24—C241—H24C109.5C8—C7—H7A110.0
H24A—C241—H24C109.5C6—C7—H7B110.0
H24B—C241—H24C109.5C8—C7—H7B110.0
C22—C23—C24121.3 (2)H7A—C7—H7B108.4
C22—C23—H23119.4C8A—C8—C7101.7 (2)
C24—C23—H23119.4C8A—C8—H8A111.4
C23—C22—C21120.9 (2)C7—C8—H8A111.4
C23—C22—H22119.5C8A—C8—H8B111.4
C21—C22—H22119.5C7—C8—H8B111.4
C3A—C3—C2105.9 (2)H8A—C8—H8B109.3
C3A—C3—H3127.0N8B—C8A—C5A118.4 (2)
C2—C3—H3127.0N8B—C8A—C8126.4 (2)
N4—C3A—C3133.6 (2)C5A—C8A—C8115.1 (2)
N4—C3A—N8B121.5 (2)C8A—N8B—N1126.75 (19)
C3—C3A—N8B105.0 (2)C8A—N8B—C3A120.4 (2)
C5—N4—C3A118.0 (2)N1—N8B—C3A112.81 (18)
N4—C5—C5A121.5 (2)
N8B—N1—C2—C30.4 (2)N4—C5—C5A—C8A1.9 (3)
N8B—N1—C2—C21179.27 (18)C51—C5—C5A—C8A178.0 (2)
N1—C2—C21—C2611.7 (3)N4—C5—C5A—C6179.4 (2)
C3—C2—C21—C26169.6 (2)C51—C5—C5A—C60.6 (4)
N1—C2—C21—C22168.1 (2)C8A—C5A—C6—C75.8 (3)
C3—C2—C21—C2210.6 (3)C5—C5A—C6—C7175.5 (3)
C22—C21—C26—C251.0 (3)C5A—C6—C7—C810.6 (3)
C2—C21—C26—C25178.7 (2)C6—C7—C8—C8A11.0 (3)
C21—C26—C25—C240.2 (3)C5—C5A—C8A—N8B1.2 (3)
C26—C25—C24—C230.3 (3)C6—C5A—C8A—N8B179.95 (19)
C26—C25—C24—C241179.3 (2)C5—C5A—C8A—C8177.4 (2)
C25—C24—C23—C220.0 (3)C6—C5A—C8A—C81.4 (3)
C241—C24—C23—C22179.6 (2)C7—C8—C8A—N8B173.7 (3)
C24—C23—C22—C210.8 (3)C7—C8—C8A—C5A7.9 (3)
C26—C21—C22—C231.3 (3)C5A—C8A—N8B—N1179.7 (2)
C2—C21—C22—C23178.4 (2)C8—C8A—N8B—N11.3 (4)
N1—C2—C3—C3A0.7 (3)C5A—C8A—N8B—C3A0.5 (3)
C21—C2—C3—C3A179.4 (2)C8—C8A—N8B—C3A178.9 (2)
C2—C3—C3A—N4178.3 (2)C2—N1—N8B—C8A179.7 (2)
C2—C3—C3A—N8B0.6 (2)C2—N1—N8B—C3A0.1 (2)
C3—C3A—N4—C5179.6 (2)N4—C3A—N8B—C8A1.5 (3)
N8B—C3A—N4—C50.8 (3)C3—C3A—N8B—C8A179.37 (19)
C3A—N4—C5—C5A0.9 (3)N4—C3A—N8B—N1178.68 (19)
C3A—N4—C5—C51179.0 (2)C3—C3A—N8B—N10.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···Cgi0.992.943.902 (3)163
Symmetry code: (i) x, y1, z.
(II) 2-(4-chlorophenyl)-5-methyl-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine top
Crystal data top
C16H14ClN3F(000) = 592
Mr = 283.75Dx = 1.421 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3040 reflections
a = 13.6800 (11) Åθ = 3.4–27.6°
b = 6.6669 (6) ŵ = 0.28 mm1
c = 15.2010 (16) ÅT = 120 K
β = 106.980 (6)°Plate, colourless
V = 1325.9 (2) Å30.34 × 0.18 × 0.03 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
3040 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2060 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.072
Detector resolution: 9.091 pixels mm-1θmax = 27.6°, θmin = 3.4°
ϕ & ω scansh = 1617
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 88
Tmin = 0.922, Tmax = 0.992l = 1719
14750 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)] = 0.056Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.141H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0726P)2 + 0.3419P]
where P = (Fo2 + 2Fc2)/3
3040 reflections(Δ/σ)max < 0.001
182 parametersΔρmax = 0.38 e Å3
0 restraintsΔρmin = 0.49 e Å3
Crystal data top
C16H14ClN3V = 1325.9 (2) Å3
Mr = 283.75Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.6800 (11) ŵ = 0.28 mm1
b = 6.6669 (6) ÅT = 120 K
c = 15.2010 (16) Å0.34 × 0.18 × 0.03 mm
β = 106.980 (6)°
Data collection top
Nonius KappaCCD
diffractometer
3040 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2060 reflections with I > 2σ(I)
Tmin = 0.922, Tmax = 0.992Rint = 0.072
14750 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0560 restraints
wR(F2) = 0.141H-atom parameters constrained
S = 1.03Δρmax = 0.38 e Å3
3040 reflectionsΔρmin = 0.49 e Å3
182 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl240.46187 (4)1.29423 (9)0.06360 (4)0.0324 (2)
N10.28435 (13)0.4384 (3)0.19754 (13)0.0230 (4)
N40.04453 (13)0.1925 (3)0.10474 (13)0.0253 (5)
N8B0.21315 (13)0.2947 (3)0.19358 (13)0.0213 (4)
C20.23879 (16)0.5622 (3)0.12731 (15)0.0218 (5)
C30.13983 (16)0.4982 (4)0.07837 (16)0.0252 (5)
C3A0.12360 (16)0.3240 (3)0.12111 (15)0.0226 (5)
C50.05428 (17)0.0352 (3)0.16026 (17)0.0256 (5)
C5A0.14297 (16)0.0047 (3)0.23560 (16)0.0236 (5)
C60.16917 (17)0.1605 (4)0.30626 (17)0.0278 (6)
C70.2702 (2)0.0880 (5)0.3741 (2)0.0533 (9)
C80.31289 (17)0.0810 (4)0.32808 (17)0.0284 (6)
C8A0.22232 (16)0.1356 (4)0.24982 (16)0.0236 (5)
C210.29402 (16)0.7402 (3)0.11099 (15)0.0222 (5)
C220.24311 (16)0.8927 (3)0.05310 (16)0.0237 (5)
C230.29389 (16)1.0622 (4)0.03824 (16)0.0258 (5)
C240.39768 (17)1.0795 (3)0.08118 (16)0.0244 (5)
C250.45133 (17)0.9302 (4)0.13841 (16)0.0267 (5)
C260.39875 (17)0.7617 (4)0.15286 (16)0.0255 (5)
C510.03146 (18)0.1142 (4)0.14149 (18)0.0320 (6)
H30.09380.56160.02670.030*
H220.17200.87980.02320.028*
H230.25801.16580.00100.031*
H250.52270.94280.16720.032*
H260.43480.65850.19220.031*
H6A0.17860.29000.27790.033*
H6B0.11530.17600.33730.033*
H7A0.25780.03850.43140.064*
H7B0.31970.20010.39020.064*
H8A0.33620.19570.37040.034*
H8B0.37020.03350.30610.034*
H51A0.08150.07170.17260.048*
H51B0.00420.24620.16460.048*
H51C0.06470.12220.07510.048*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl240.0293 (3)0.0289 (4)0.0364 (4)0.0089 (3)0.0054 (3)0.0011 (3)
N10.0214 (9)0.0211 (10)0.0248 (10)0.0003 (8)0.0040 (8)0.0008 (8)
N40.0190 (9)0.0258 (11)0.0295 (11)0.0006 (8)0.0046 (8)0.0033 (9)
N8B0.0190 (9)0.0224 (10)0.0213 (10)0.0008 (8)0.0040 (7)0.0002 (8)
C20.0219 (11)0.0220 (12)0.0205 (12)0.0020 (9)0.0049 (9)0.0019 (10)
C30.0215 (12)0.0268 (13)0.0253 (13)0.0020 (10)0.0037 (9)0.0033 (11)
C3A0.0184 (11)0.0230 (13)0.0249 (12)0.0017 (9)0.0040 (9)0.0010 (10)
C50.0233 (12)0.0247 (13)0.0293 (13)0.0031 (10)0.0085 (10)0.0003 (11)
C5A0.0240 (12)0.0216 (12)0.0266 (13)0.0025 (10)0.0095 (10)0.0016 (10)
C60.0273 (12)0.0268 (13)0.0310 (14)0.0031 (10)0.0114 (10)0.0065 (11)
C70.0346 (15)0.060 (2)0.055 (2)0.0107 (14)0.0031 (13)0.0317 (17)
C80.0226 (11)0.0326 (14)0.0272 (13)0.0009 (10)0.0029 (9)0.0073 (11)
C8A0.0219 (11)0.0250 (12)0.0242 (13)0.0042 (9)0.0074 (9)0.0007 (10)
C210.0217 (11)0.0237 (12)0.0206 (12)0.0003 (9)0.0053 (9)0.0018 (9)
C220.0191 (11)0.0264 (13)0.0243 (12)0.0007 (9)0.0044 (9)0.0016 (10)
C230.0259 (12)0.0226 (13)0.0275 (13)0.0030 (10)0.0057 (10)0.0016 (10)
C240.0250 (12)0.0222 (12)0.0271 (13)0.0048 (10)0.0095 (10)0.0046 (10)
C250.0229 (12)0.0281 (13)0.0254 (13)0.0014 (10)0.0013 (9)0.0037 (10)
C260.0231 (12)0.0261 (13)0.0251 (13)0.0027 (9)0.0033 (9)0.0000 (10)
C510.0250 (12)0.0286 (14)0.0389 (15)0.0041 (10)0.0038 (10)0.0057 (12)
Geometric parameters (Å, º) top
N1—C21.349 (3)N4—C51.328 (3)
N1—N8B1.355 (3)C5—C5A1.419 (3)
C2—C31.407 (3)C5—C511.501 (3)
C2—C211.466 (3)C51—H51A0.98
C21—C221.391 (3)C51—H51B0.98
C21—C261.395 (3)C51—H51C0.98
C26—C251.385 (3)C5A—C8A1.360 (3)
C26—H260.95C5A—C61.507 (3)
C25—C241.384 (3)C6—C71.541 (4)
C25—H250.95C6—H6A0.99
C24—C231.383 (3)C6—H6B0.99
C24—Cl241.740 (2)C7—C81.530 (4)
C23—C221.379 (3)C7—H7A0.99
C23—H230.95C7—H7B0.99
C22—H220.95C8—C8A1.491 (3)
C3—C3A1.380 (3)C8—H8A0.99
C3—H30.95C8—H8B0.99
C3A—N41.358 (3)C8A—N8B1.345 (3)
C3A—N8B1.401 (3)
C2—N1—N8B103.73 (17)C5—C51—H51B109.5
N1—C2—C3112.5 (2)H51A—C51—H51B109.5
N1—C2—C21119.15 (18)C5—C51—H51C109.5
C3—C2—C21128.3 (2)H51A—C51—H51C109.5
C22—C21—C26118.1 (2)H51B—C51—H51C109.5
C22—C21—C2120.72 (19)C8A—C5A—C5119.4 (2)
C26—C21—C2121.2 (2)C8A—C5A—C6110.07 (19)
C25—C26—C21121.5 (2)C5—C5A—C6130.5 (2)
C25—C26—H26119.2C5A—C6—C7103.2 (2)
C21—C26—H26119.2C5A—C6—H6A111.1
C24—C25—C26118.6 (2)C7—C6—H6A111.1
C24—C25—H25120.7C5A—C6—H6B111.1
C26—C25—H25120.7C7—C6—H6B111.1
C23—C24—C25121.3 (2)H6A—C6—H6B109.1
C23—C24—Cl24119.37 (18)C8—C7—C6108.2 (2)
C25—C24—Cl24119.33 (17)C8—C7—H7A110.1
C22—C23—C24119.2 (2)C6—C7—H7A110.1
C22—C23—H23120.4C8—C7—H7B110.1
C24—C23—H23120.4C6—C7—H7B110.1
C23—C22—C21121.3 (2)H7A—C7—H7B108.4
C23—C22—H22119.4C8A—C8—C7101.85 (19)
C21—C22—H22119.4C8A—C8—H8A111.4
C3A—C3—C2105.58 (19)C7—C8—H8A111.4
C3A—C3—H3127.2C8A—C8—H8B111.4
C2—C3—H3127.2C7—C8—H8B111.4
N4—C3A—C3133.3 (2)H8A—C8—H8B109.3
N4—C3A—N8B121.4 (2)N8B—C8A—C5A118.9 (2)
C3—C3A—N8B105.28 (19)N8B—C8A—C8127.0 (2)
C5—N4—C3A117.82 (19)C5A—C8A—C8114.1 (2)
N4—C5—C5A122.0 (2)C8A—N8B—N1126.65 (18)
N4—C5—C51118.4 (2)C8A—N8B—C3A120.49 (19)
C5A—C5—C51119.7 (2)N1—N8B—C3A112.85 (18)
C5—C51—H51A109.5
N8B—N1—C2—C30.4 (2)N4—C5—C5A—C8A2.6 (4)
N8B—N1—C2—C21179.24 (19)C51—C5—C5A—C8A177.0 (2)
N1—C2—C21—C22166.2 (2)N4—C5—C5A—C6179.7 (2)
C3—C2—C21—C2213.5 (4)C51—C5—C5A—C60.7 (4)
N1—C2—C21—C2613.8 (3)C8A—C5A—C6—C78.7 (3)
C3—C2—C21—C26166.5 (2)C5—C5A—C6—C7173.4 (3)
C22—C21—C26—C250.5 (4)C5A—C6—C7—C815.2 (3)
C2—C21—C26—C25179.5 (2)C6—C7—C8—C8A15.6 (3)
C21—C26—C25—C240.2 (4)C5—C5A—C8A—N8B2.2 (3)
C26—C25—C24—C230.6 (4)C6—C5A—C8A—N8B179.7 (2)
C26—C25—C24—Cl24178.95 (18)C5—C5A—C8A—C8176.9 (2)
C25—C24—C23—C220.1 (4)C6—C5A—C8A—C81.2 (3)
Cl24—C24—C23—C22179.35 (18)C7—C8—C8A—N8B170.4 (3)
C24—C23—C22—C210.6 (4)C7—C8—C8A—C5A10.6 (3)
C26—C21—C22—C231.0 (4)C5A—C8A—N8B—N1179.6 (2)
C2—C21—C22—C23179.0 (2)C8—C8A—N8B—N10.7 (4)
N1—C2—C3—C3A0.1 (3)C5A—C8A—N8B—C3A0.5 (3)
C21—C2—C3—C3A179.7 (2)C8—C8A—N8B—C3A178.4 (2)
C2—C3—C3A—N4178.6 (2)C2—N1—N8B—C8A180.0 (2)
C2—C3—C3A—N8B0.5 (2)C2—N1—N8B—C3A0.8 (2)
C3—C3A—N4—C5179.5 (3)N4—C3A—N8B—C8A0.9 (3)
N8B—C3A—N4—C50.5 (3)C3—C3A—N8B—C8A179.9 (2)
C3A—N4—C5—C5A1.2 (3)N4—C3A—N8B—N1178.3 (2)
C3A—N4—C5—C51178.5 (2)C3—C3A—N8B—N10.9 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···Cgi0.992.873.820 (3)160
Symmetry code: (i) x, y1, z.
(III) 2-(4-bromophenyl)-5-methyl-7,8-dihydro-6H- cyclopenta[g]pyrazolo[1,5-a]pyrimidine top
Crystal data top
C16H14BrN3F(000) = 664
Mr = 328.21Dx = 1.597 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3125 reflections
a = 13.5387 (6) Åθ = 3.3–27.5°
b = 6.8551 (2) ŵ = 3.00 mm1
c = 15.2767 (7) ÅT = 120 K
β = 105.708 (2)°Plate, colourless
V = 1364.87 (10) Å30.66 × 0.20 × 0.02 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
3125 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2438 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.069
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.3°
ϕ and ω scansh = 1717
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 88
Tmin = 0.242, Tmax = 0.942l = 1919
18357 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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0473P)2 + 0.618P]
where P = (Fo2 + 2Fc2)/3
3125 reflections(Δ/σ)max = 0.001
186 parametersΔρmax = 0.41 e Å3
2 restraintsΔρmin = 0.68 e Å3
Crystal data top
C16H14BrN3V = 1364.87 (10) Å3
Mr = 328.21Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.5387 (6) ŵ = 3.00 mm1
b = 6.8551 (2) ÅT = 120 K
c = 15.2767 (7) Å0.66 × 0.20 × 0.02 mm
β = 105.708 (2)°
Data collection top
Nonius KappaCCD
diffractometer
3125 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2438 reflections with I > 2σ(I)
Tmin = 0.242, Tmax = 0.942Rint = 0.069
18357 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0372 restraints
wR(F2) = 0.096H-atom parameters constrained
S = 1.05Δρmax = 0.41 e Å3
3125 reflectionsΔρmin = 0.68 e Å3
186 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Br240.46697 (2)1.29662 (4)0.06561 (2)0.02998 (12)
N10.28031 (16)0.4414 (3)0.19783 (15)0.0206 (5)
N40.04328 (17)0.1944 (3)0.10205 (16)0.0242 (5)
N8B0.20942 (16)0.2989 (3)0.19183 (15)0.0199 (5)
C20.23623 (19)0.5604 (4)0.12763 (18)0.0210 (6)
C30.13854 (19)0.4957 (4)0.07760 (18)0.0219 (6)
C3A0.12190 (19)0.3252 (4)0.11961 (18)0.0206 (6)
C50.0517 (2)0.0409 (4)0.15732 (19)0.0234 (6)
C5A0.13850 (19)0.0146 (4)0.23266 (18)0.0213 (6)
C60.1635 (2)0.1454 (4)0.3035 (2)0.0280 (6)
C70.2581 (3)0.0600 (9)0.3765 (4)0.0328 (14)0.853 (17)
C7A0.2785 (9)0.114 (2)0.351 (2)0.030*0.147 (17)
C80.3055 (2)0.0958 (4)0.32725 (19)0.0276 (6)
C8A0.2175 (2)0.1445 (4)0.24852 (18)0.0210 (5)
C210.2917 (2)0.7362 (4)0.11228 (19)0.0206 (5)
C220.2412 (2)0.8831 (4)0.05358 (18)0.0220 (6)
C230.2926 (2)1.0497 (4)0.03934 (19)0.0237 (6)
C240.3960 (2)1.0683 (4)0.08394 (18)0.0213 (6)
C250.4487 (2)0.9254 (4)0.14247 (19)0.0233 (6)
C260.3959 (2)0.7598 (4)0.15640 (19)0.0234 (6)
C510.0339 (2)0.1050 (4)0.1373 (2)0.0315 (7)
H30.09370.55640.02600.026*
H6A0.18140.26840.27750.034*
H6B0.10530.16950.32970.034*
H7A0.23610.00060.42720.039*0.853 (17)
H7B0.30860.16420.40130.039*0.853 (17)
H7C0.32070.21130.32960.036*0.147 (17)
H7D0.29150.12890.41800.036*0.147 (17)
H8A0.32890.21110.36640.033*
H8B0.36380.04230.30730.033*
H220.17050.86850.02300.026*
H230.25771.14950.00030.028*
H250.51950.94050.17240.028*
H260.43100.66100.19650.028*
H51A0.06290.11570.07140.047*
H51B0.08730.06230.16530.047*
H51C0.00730.23220.16210.047*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br240.02841 (17)0.02698 (18)0.03312 (19)0.00983 (12)0.00588 (13)0.00026 (12)
N10.0178 (11)0.0214 (11)0.0224 (12)0.0014 (9)0.0052 (9)0.0008 (9)
N40.0172 (11)0.0244 (12)0.0295 (13)0.0022 (9)0.0039 (10)0.0016 (10)
N8B0.0171 (10)0.0209 (11)0.0209 (12)0.0012 (9)0.0040 (9)0.0015 (9)
C20.0181 (13)0.0233 (13)0.0221 (14)0.0022 (10)0.0061 (11)0.0019 (11)
C30.0178 (13)0.0236 (13)0.0223 (14)0.0012 (11)0.0020 (11)0.0039 (11)
C3A0.0158 (12)0.0223 (13)0.0231 (14)0.0027 (10)0.0041 (11)0.0006 (10)
C50.0206 (13)0.0207 (13)0.0307 (16)0.0015 (11)0.0097 (12)0.0009 (11)
C5A0.0205 (13)0.0214 (13)0.0244 (14)0.0037 (11)0.0106 (11)0.0001 (11)
C60.0308 (15)0.0256 (14)0.0319 (17)0.0028 (12)0.0157 (13)0.0068 (12)
C70.0281 (19)0.039 (2)0.032 (2)0.0042 (18)0.0098 (17)0.0157 (18)
C80.0233 (14)0.0323 (15)0.0255 (15)0.0034 (12)0.0036 (12)0.0073 (12)
C8A0.0197 (13)0.0212 (12)0.0232 (15)0.0041 (11)0.0078 (11)0.0027 (11)
C210.0190 (13)0.0204 (12)0.0227 (14)0.0003 (10)0.0064 (11)0.0021 (10)
C220.0156 (12)0.0256 (13)0.0233 (15)0.0032 (11)0.0029 (11)0.0003 (11)
C230.0224 (14)0.0209 (13)0.0269 (15)0.0024 (11)0.0050 (12)0.0016 (11)
C240.0221 (13)0.0195 (12)0.0237 (15)0.0037 (10)0.0084 (11)0.0029 (10)
C250.0185 (13)0.0252 (14)0.0234 (15)0.0014 (11)0.0010 (11)0.0047 (11)
C260.0220 (13)0.0228 (13)0.0226 (14)0.0029 (11)0.0012 (11)0.0011 (11)
C510.0246 (14)0.0266 (15)0.0407 (18)0.0034 (12)0.0043 (13)0.0052 (13)
Geometric parameters (Å, º) top
N1—C21.351 (3)C5—C511.498 (4)
N1—N8B1.355 (3)C51—H51A0.98
C2—C31.408 (4)C51—H51B0.98
C2—C211.472 (4)C51—H51C0.98
C21—C261.398 (4)C5A—C8A1.362 (4)
C21—C221.398 (4)C5A—C61.513 (4)
C22—C231.385 (4)C6—C7A1.545 (5)
C22—H220.95C6—C71.566 (5)
C23—C241.386 (4)C6—H6A0.99
C23—H230.95C6—H6B0.99
C24—C251.387 (4)C7—C81.543 (4)
C24—Br241.897 (3)C7—H7A0.99
C25—C261.389 (4)C7—H7B0.99
C25—H250.95C7A—C81.555 (5)
C26—H260.95C7A—H7C0.99
C3—C3A1.381 (4)C7A—H7D0.99
C3—H30.95C8—C8A1.484 (4)
C3A—N41.361 (3)C8—H8A0.99
C3A—N8B1.395 (3)C8—H8B0.99
N4—C51.335 (3)C8A—N8B1.353 (3)
C5—C5A1.417 (4)
C2—N1—N8B103.2 (2)C8A—C5A—C6109.5 (2)
N1—C2—C3112.9 (2)C5—C5A—C6130.5 (2)
N1—C2—C21119.1 (2)C5A—C6—C7A103.9 (5)
C3—C2—C21128.0 (2)C5A—C6—C7102.7 (2)
C26—C21—C22118.7 (2)C5A—C6—H6A111.2
C26—C21—C2120.6 (2)C7A—C6—H6A89.0
C22—C21—C2120.6 (2)C7—C6—H6A111.2
C23—C22—C21121.0 (2)C5A—C6—H6B111.2
C23—C22—H22119.5C7A—C6—H6B130.0
C21—C22—H22119.5C7—C6—H6B111.2
C22—C23—C24118.8 (2)H6A—C6—H6B109.1
C22—C23—H23120.6C8—C7—C6106.2 (3)
C24—C23—H23120.6C8—C7—H7A110.5
C23—C24—C25121.8 (2)C6—C7—H7A110.5
C23—C24—Br24119.2 (2)C8—C7—H7B110.5
C25—C24—Br24119.02 (19)C6—C7—H7B110.5
C24—C25—C26118.7 (2)H7A—C7—H7B108.7
C24—C25—H25120.7C6—C7A—C8106.6 (4)
C26—C25—H25120.7C6—C7A—H7C110.4
C25—C26—C21121.0 (3)C8—C7A—H7C110.4
C25—C26—H26119.5C6—C7A—H7D110.4
C21—C26—H26119.5C8—C7A—H7D110.4
C3A—C3—C2105.2 (2)H7C—C7A—H7D108.6
C3A—C3—H3127.4C8A—C8—C7101.7 (2)
C2—C3—H3127.4C8A—C8—C7A102.2 (5)
N4—C3A—C3133.1 (3)C8A—C8—H8A111.4
N4—C3A—N8B121.5 (2)C7—C8—H8A111.4
C3—C3A—N8B105.4 (2)C7A—C8—H8A130.8
C5—N4—C3A117.8 (2)C8A—C8—H8B111.4
N4—C5—C5A121.6 (2)C7—C8—H8B111.4
N4—C5—C51117.9 (2)C7A—C8—H8B89.3
C5A—C5—C51120.4 (2)H8A—C8—H8B109.3
C5—C51—H51A109.5N8B—C8A—C5A118.3 (2)
C5—C51—H51B109.5N8B—C8A—C8127.1 (2)
H51A—C51—H51B109.5C5A—C8A—C8114.6 (2)
C5—C51—H51C109.5C8A—N8B—N1126.0 (2)
H51A—C51—H51C109.5C8A—N8B—C3A120.8 (2)
H51B—C51—H51C109.5N1—N8B—C3A113.3 (2)
C8A—C5A—C5120.0 (2)
N8B—N1—C2—C30.2 (3)C5—C5A—C6—C7A166.9 (15)
N8B—N1—C2—C21179.7 (2)C8A—C5A—C6—C713.1 (4)
N1—C2—C21—C2613.4 (4)C5—C5A—C6—C7168.4 (4)
C3—C2—C21—C26167.2 (3)C5A—C6—C7—C821.8 (5)
N1—C2—C21—C22166.4 (2)C7A—C6—C7—C874.0 (10)
C3—C2—C21—C2213.1 (4)C5A—C6—C7A—C817 (2)
C26—C21—C22—C230.3 (4)C7—C6—C7A—C872.8 (11)
C2—C21—C22—C23179.5 (2)C6—C7—C8—C8A22.0 (5)
C21—C22—C23—C240.5 (4)C6—C7—C8—C7A71.9 (9)
C22—C23—C24—C250.3 (4)C6—C7A—C8—C8A16 (2)
C22—C23—C24—Br24179.6 (2)C6—C7A—C8—C774.9 (13)
C23—C24—C25—C260.0 (4)C5—C5A—C8A—N8B1.3 (4)
Br24—C24—C25—C26179.2 (2)C6—C5A—C8A—N8B179.9 (2)
C24—C25—C26—C210.2 (4)C5—C5A—C8A—C8177.6 (2)
C22—C21—C26—C250.1 (4)C6—C5A—C8A—C81.0 (3)
C2—C21—C26—C25179.8 (3)C7—C8—C8A—N8B166.4 (4)
N1—C2—C3—C3A0.4 (3)C7A—C8—C8A—N8B168.9 (15)
C21—C2—C3—C3A179.9 (3)C7—C8—C8A—C5A14.8 (4)
C2—C3—C3A—N4178.6 (3)C7A—C8—C8A—C5A9.9 (15)
C2—C3—C3A—N8B0.4 (3)C5A—C8A—N8B—N1179.8 (2)
C3—C3A—N4—C5179.9 (3)C8—C8A—N8B—N11.4 (4)
N8B—C3A—N4—C51.1 (4)C5A—C8A—N8B—C3A0.6 (4)
C3A—N4—C5—C5A0.8 (4)C8—C8A—N8B—C3A179.3 (3)
C3A—N4—C5—C51179.0 (2)C2—N1—N8B—C8A179.2 (2)
N4—C5—C5A—C8A2.0 (4)C2—N1—N8B—C3A0.1 (3)
C51—C5—C5A—C8A177.7 (3)N4—C3A—N8B—C8A1.9 (4)
N4—C5—C5A—C6179.6 (3)C3—C3A—N8B—C8A179.0 (2)
C51—C5—C5A—C60.6 (4)N4—C3A—N8B—N1178.8 (2)
C8A—C5A—C6—C7A11.6 (15)C3—C3A—N8B—N10.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···Cgi0.992.993.942 (3)161
Symmetry code: (i) x, y1, z.
(IV) (4-methoxyphenyl)-5-methyl- 7,8-dihydro-6H-cyclopenta[g]pyrazolo[1,5-a]pyrimidine top
Crystal data top
C17H17N3OF(000) = 592
Mr = 279.34Dx = 1.336 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3192 reflections
a = 9.4691 (3) Åθ = 3.0–27.5°
b = 8.1711 (2) ŵ = 0.09 mm1
c = 18.0278 (6) ÅT = 120 K
β = 95.3430 (14)°Block, colourless
V = 1388.80 (7) Å30.40 × 0.38 × 0.30 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
3192 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2520 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.0°
ϕ and ω scansh = 1212
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 910
Tmin = 0.956, Tmax = 0.975l = 1823
16180 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.042H-atom parameters constrained
wR(F2) = 0.126 w = 1/[σ2(Fo2) + (0.0744P)2 + 0.2357P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
3192 reflectionsΔρmax = 0.28 e Å3
193 parametersΔρmin = 0.25 e Å3
0 restraintsExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.028 (5)
Crystal data top
C17H17N3OV = 1388.80 (7) Å3
Mr = 279.34Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.4691 (3) ŵ = 0.09 mm1
b = 8.1711 (2) ÅT = 120 K
c = 18.0278 (6) Å0.40 × 0.38 × 0.30 mm
β = 95.3430 (14)°
Data collection top
Nonius KappaCCD
diffractometer
3192 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2520 reflections with I > 2σ(I)
Tmin = 0.956, Tmax = 0.975Rint = 0.033
16180 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.126H-atom parameters constrained
S = 1.06Δρmax = 0.28 e Å3
3192 reflectionsΔρmin = 0.25 e Å3
193 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O240.02704 (11)0.07954 (12)0.15877 (5)0.0299 (3)
N10.23322 (11)0.78754 (13)0.06768 (6)0.0204 (3)
N40.51632 (11)1.03723 (14)0.14924 (6)0.0216 (3)
N8B0.31726 (11)0.92262 (13)0.07384 (6)0.0189 (3)
C20.28422 (13)0.69345 (15)0.12582 (7)0.0190 (3)
C30.39961 (13)0.76585 (16)0.16825 (7)0.0202 (3)
C3A0.42028 (13)0.91482 (16)0.13414 (7)0.0194 (3)
C50.51003 (13)1.16535 (16)0.10395 (7)0.0205 (3)
C5A0.40583 (13)1.17745 (15)0.04224 (7)0.0198 (3)
C60.37829 (14)1.31336 (16)0.01357 (7)0.0231 (3)
C70.25751 (14)1.24589 (17)0.06941 (7)0.0256 (3)
C80.20303 (14)1.08492 (16)0.03653 (7)0.0235 (3)
C8A0.30944 (13)1.05514 (16)0.02812 (7)0.0191 (3)
C210.21810 (13)0.53367 (16)0.13736 (6)0.0185 (3)
C220.27118 (13)0.42800 (16)0.19362 (7)0.0215 (3)
C230.21110 (13)0.27504 (16)0.20273 (7)0.0215 (3)
C240.09482 (13)0.22649 (16)0.15516 (7)0.0209 (3)
C250.03881 (14)0.33155 (16)0.09878 (7)0.0233 (3)
C260.09968 (13)0.48305 (16)0.09039 (7)0.0214 (3)
C510.61754 (15)1.29849 (17)0.11988 (8)0.0277 (3)
C2410.07396 (16)0.02903 (17)0.21789 (8)0.0296 (3)
H30.45220.72210.21120.024*
H6A0.46421.33740.03900.028*
H6B0.34801.41430.01080.028*
H7A0.17951.32660.07670.031*
H7B0.29371.22440.11830.031*
H8A0.10671.09890.02030.028*
H8B0.20190.99430.07310.028*
H220.35020.46110.22650.026*
H230.24930.20410.24120.026*
H24A0.17510.05240.21610.044*
H24B0.02000.13130.21250.044*
H24C0.05910.02190.26570.044*
H250.04100.29880.06630.028*
H260.06070.55430.05220.026*
H51A0.56951.39910.13320.041*
H51B0.66751.31820.07550.041*
H51C0.68591.26530.16130.041*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O240.0327 (6)0.0260 (6)0.0297 (5)0.0103 (4)0.0039 (4)0.0064 (4)
N10.0200 (5)0.0212 (6)0.0196 (6)0.0038 (4)0.0004 (4)0.0001 (4)
N40.0192 (6)0.0250 (6)0.0203 (6)0.0035 (4)0.0002 (4)0.0012 (4)
N8B0.0174 (5)0.0217 (6)0.0173 (5)0.0027 (4)0.0000 (4)0.0007 (4)
C20.0182 (6)0.0225 (7)0.0163 (6)0.0001 (5)0.0025 (5)0.0012 (5)
C30.0190 (6)0.0240 (7)0.0172 (6)0.0006 (5)0.0003 (5)0.0002 (5)
C3A0.0170 (6)0.0253 (7)0.0156 (6)0.0011 (5)0.0000 (5)0.0020 (5)
C50.0186 (6)0.0240 (7)0.0192 (6)0.0010 (5)0.0028 (5)0.0021 (5)
C5A0.0192 (6)0.0223 (7)0.0186 (6)0.0003 (5)0.0047 (5)0.0015 (5)
C60.0245 (7)0.0229 (7)0.0223 (7)0.0001 (5)0.0041 (5)0.0009 (5)
C70.0247 (7)0.0274 (7)0.0241 (7)0.0016 (6)0.0008 (5)0.0046 (5)
C80.0236 (7)0.0262 (7)0.0200 (6)0.0012 (5)0.0019 (5)0.0012 (5)
C8A0.0192 (6)0.0217 (7)0.0167 (6)0.0005 (5)0.0031 (5)0.0009 (5)
C210.0172 (6)0.0221 (7)0.0165 (6)0.0004 (5)0.0025 (5)0.0018 (5)
C220.0186 (6)0.0264 (7)0.0190 (6)0.0011 (5)0.0013 (5)0.0019 (5)
C230.0219 (6)0.0246 (7)0.0177 (6)0.0015 (5)0.0004 (5)0.0021 (5)
C240.0215 (6)0.0220 (7)0.0197 (6)0.0026 (5)0.0046 (5)0.0008 (5)
C250.0205 (7)0.0280 (7)0.0205 (6)0.0046 (5)0.0019 (5)0.0002 (5)
C260.0212 (6)0.0256 (7)0.0171 (6)0.0013 (5)0.0005 (5)0.0027 (5)
C510.0267 (7)0.0288 (7)0.0270 (7)0.0075 (6)0.0005 (6)0.0003 (6)
C2410.0329 (8)0.0259 (7)0.0303 (8)0.0022 (6)0.0054 (6)0.0073 (6)
Geometric parameters (Å, º) top
N1—C21.3522 (16)C3A—N41.3622 (16)
N1—N8B1.3592 (14)C3A—N8B1.3928 (15)
C2—C31.4047 (17)N4—C51.3255 (17)
C2—C211.4710 (18)C5—C5A1.4202 (18)
C21—C221.3900 (18)C5—C511.4993 (18)
C21—C261.4031 (18)C51—H51A0.98
C22—C231.3893 (18)C51—H51B0.98
C22—H220.95C51—H51C0.98
C23—C241.3890 (18)C5A—C8A1.3614 (18)
C23—H230.95C5A—C61.5049 (18)
C24—O241.3659 (16)C6—C71.5528 (18)
C24—C251.3968 (18)C6—H6A0.99
O24—C2411.4255 (16)C6—H6B0.99
C241—H24A0.98C7—C81.5507 (18)
C241—H24B0.98C7—H7A0.99
C241—H24C0.98C7—H7B0.99
C25—C261.3798 (18)C8—C8A1.4880 (18)
C25—H250.95C8—H8A0.99
C26—H260.95C8—H8B0.99
C3—C3A1.3858 (18)C8A—N8B1.3587 (16)
C3—H30.95
C2—N1—N8B103.55 (10)N4—C5—C5A121.71 (12)
N1—C2—C3112.71 (11)N4—C5—C51117.67 (11)
N1—C2—C21119.22 (11)C5A—C5—C51120.62 (11)
C3—C2—C21128.06 (11)C5—C51—H51A109.5
C22—C21—C26118.14 (12)C5—C51—H51B109.5
C22—C21—C2121.65 (11)H51A—C51—H51B109.5
C26—C21—C2120.20 (11)C5—C51—H51C109.5
C23—C22—C21121.39 (12)H51A—C51—H51C109.5
C23—C22—H22119.3H51B—C51—H51C109.5
C21—C22—H22119.3C8A—C5A—C5120.01 (12)
C24—C23—C22119.59 (12)C8A—C5A—C6110.20 (11)
C24—C23—H23120.2C5—C5A—C6129.77 (12)
C22—C23—H23120.2C5A—C6—C7104.05 (10)
O24—C24—C23124.80 (12)C5A—C6—H6A110.9
O24—C24—C25115.26 (11)C7—C6—H6A110.9
C23—C24—C25119.94 (12)C5A—C6—H6B110.9
C24—O24—C241117.88 (10)C7—C6—H6B110.9
O24—C241—H24A109.5H6A—C6—H6B109.0
O24—C241—H24B109.5C8—C7—C6107.73 (10)
H24A—C241—H24B109.5C8—C7—H7A110.2
O24—C241—H24C109.5C6—C7—H7A110.2
H24A—C241—H24C109.5C8—C7—H7B110.2
H24B—C241—H24C109.5C6—C7—H7B110.2
C26—C25—C24119.80 (12)H7A—C7—H7B108.5
C26—C25—H25120.1C8A—C8—C7102.30 (10)
C24—C25—H25120.1C8A—C8—H8A111.3
C25—C26—C21121.12 (12)C7—C8—H8A111.3
C25—C26—H26119.4C8A—C8—H8B111.3
C21—C26—H26119.4C7—C8—H8B111.3
C3A—C3—C2105.25 (11)H8A—C8—H8B109.2
C3A—C3—H3127.4N8B—C8A—C5A118.29 (12)
C2—C3—H3127.4N8B—C8A—C8126.88 (11)
N4—C3A—C3132.49 (12)C5A—C8A—C8114.82 (11)
N4—C3A—N8B121.90 (11)C8A—N8B—N1126.82 (11)
C3—C3A—N8B105.60 (11)C8A—N8B—C3A120.31 (11)
C5—N4—C3A117.77 (11)N1—N8B—C3A112.87 (10)
N8B—N1—C2—C30.48 (13)C3A—N4—C5—C51178.90 (11)
N8B—N1—C2—C21179.92 (10)N4—C5—C5A—C8A0.33 (19)
N1—C2—C21—C22176.30 (11)C51—C5—C5A—C8A179.55 (12)
C3—C2—C21—C223.0 (2)N4—C5—C5A—C6177.83 (12)
N1—C2—C21—C262.73 (18)C51—C5—C5A—C62.3 (2)
C3—C2—C21—C26177.93 (12)C8A—C5A—C6—C75.51 (14)
C26—C21—C22—C231.18 (18)C5—C5A—C6—C7176.19 (12)
C2—C21—C22—C23177.88 (11)C5A—C6—C7—C89.12 (14)
C21—C22—C23—C240.52 (19)C6—C7—C8—C8A9.16 (13)
C22—C23—C24—O24179.95 (11)C5—C5A—C8A—N8B0.70 (18)
C22—C23—C24—C250.21 (18)C6—C5A—C8A—N8B179.20 (10)
C23—C24—O24—C2413.40 (18)C5—C5A—C8A—C8178.05 (11)
C25—C24—O24—C241176.35 (11)C6—C5A—C8A—C80.44 (15)
O24—C24—C25—C26179.98 (11)C7—C8—C8A—N8B175.22 (12)
C23—C24—C25—C260.25 (19)C7—C8—C8A—C5A6.15 (14)
C24—C25—C26—C210.43 (19)C5A—C8A—N8B—N1178.31 (11)
C22—C21—C26—C251.13 (18)C8—C8A—N8B—N13.1 (2)
C2—C21—C26—C25177.94 (11)C5A—C8A—N8B—C3A1.05 (17)
N1—C2—C3—C3A0.38 (14)C8—C8A—N8B—C3A177.54 (12)
C21—C2—C3—C3A179.75 (12)C2—N1—N8B—C8A179.81 (11)
C2—C3—C3A—N4179.23 (13)C2—N1—N8B—C3A0.42 (13)
C2—C3—C3A—N8B0.10 (13)N4—C3A—N8B—C8A0.39 (18)
C3—C3A—N4—C5178.38 (13)C3—C3A—N8B—C8A179.64 (10)
N8B—C3A—N4—C50.64 (17)N4—C3A—N8B—N1179.05 (11)
C3A—N4—C5—C5A0.99 (18)C3—C3A—N8B—N10.20 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C22—H22···N4i0.952.543.436 (2)156
Symmetry code: (i) x+1, y1/2, z+1/2.

Experimental details

(I)(II)(III)(IV)
Crystal data
Chemical formulaC17H17N3C16H14ClN3C16H14BrN3C17H17N3O
Mr263.34283.75328.21279.34
Crystal system, space groupMonoclinic, P21/cMonoclinic, P21/cMonoclinic, P21/cMonoclinic, P21/c
Temperature (K)120120120120
a, b, c (Å)13.2882 (7), 6.8383 (4), 15.1947 (8)13.6800 (11), 6.6669 (6), 15.2010 (16)13.5387 (6), 6.8551 (2), 15.2767 (7)9.4691 (3), 8.1711 (2), 18.0278 (6)
β (°) 104.018 (3) 106.980 (6) 105.708 (2) 95.3430 (14)
V3)1339.60 (13)1325.9 (2)1364.87 (10)1388.80 (7)
Z4444
Radiation typeMo KαMo KαMo KαMo Kα
µ (mm1)0.080.283.000.09
Crystal size (mm)0.52 × 0.08 × 0.040.34 × 0.18 × 0.030.66 × 0.20 × 0.020.40 × 0.38 × 0.30
Data collection
DiffractometerNonius KappaCCD
diffractometer
Nonius KappaCCD
diffractometer
Nonius KappaCCD
diffractometer
Nonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)
Multi-scan
(SADABS; Sheldrick, 2003)
Multi-scan
(SADABS; Sheldrick, 2003)
Multi-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.955, 0.9970.922, 0.9920.242, 0.9420.956, 0.975
No. of measured, independent and
observed [I > 2σ(I)] reflections
13947, 3076, 1640 14750, 3040, 2060 18357, 3125, 2438 16180, 3192, 2520
Rint0.0850.0720.0690.033
(sin θ/λ)max1)0.6500.6520.6500.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.175, 1.01 0.056, 0.141, 1.03 0.037, 0.096, 1.05 0.042, 0.126, 1.06
No. of reflections3076304031253192
No. of parameters183182186193
No. of restraints0020
H-atom treatmentH-atom parameters constrainedH-atom parameters constrainedH-atom parameters constrainedH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.35, 0.290.38, 0.490.41, 0.680.28, 0.25

Computer programs: COLLECT (Hooft, 1999), DENZO (Otwinowski & Minor, 1997) and COLLECT, DENZO and COLLECT, WinGX (Farrugia, 1999) and SIR92 (Altomare et al., 1993), OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), OSCAIL (McArdle, 2003) and SHELXL97 (Sheldrick, 1997), OSCAIL and SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 and PRPKAPPA (Ferguson, 1999).

Selected geometric parameters (Å, °) for compounds (I)–(IV) top
Parameter(I)(II)(III)(IV)
N1-C21.348 (3)1.349 (2)1.351 (3)1.3522 (16)
C2-C31.400 (3)1.407 (3)1.408 (4)1.4047 (18)
C3-C3A1.380 (3)1.380 (3)1.381 (4)1.3858 (18)
C3A-N41.356 (3)1.358 (3)1.361 (3)1.3622 (16)
N4-C51.333 (3)1.328 (3)1.335 (3)1.3255 (17)
C5-C5A1.418 (3)1.419 (3)1.417 (4)1.4202 (18)
C5A-C8A1.358 (3)1.360 (3)1.362 (4)1.3614 (18)
C8A-N8B1.354 (3)1.345 (3)1.353 (3)1.3587 (16)
N8B-N11.357 (3)1.355 (3)1.355 (3)1.3592 (14)
C3A-N8B1.403 (3)1.401 (3)1.395 (3)1.3928 (15)
C23-C24-O24124.80 (12)
C25-C24-O24115.26 (11)
C24-O24-C241117.88 (10)
N1-C2-C21-C22-168.1 (2)-166.2 (2)-166.4 (2)176.30 (11)
C23-C24-O24-C2413.40 (18)
Hydrogen bonds and short intramolecular contacts (Å, °) for compounds (I)–(IV) top
CompoundD-H···AD-HH···AD···AD-H···A
(I)C6-H6A···Cgi0.992.943.902 (3)163
(II)C6-H6A···Cgi0.992.873.820 (3)160
(III)C6-H6A···Cgi0.992.993.942 (3)161
(IV)C22-H22···N4ii0.952.543.436 (2)156
Symmetry codes: (i) x, −1 + y, z; (ii) 1 − x, −0.5 + y, 0.5 − z.

Cg is the centroid of ring N1, C2, C3, C3A, N8B
 

Acknowledgements

X-ray data were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England. JC thanks the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) and the Universidad de Jaén for financial support. JQ and JP thank COLCIENCIAS and UNIVALLE (Universidad del Valle, Colombia) for financial support.

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