organic compounds
3,4,7-Trimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-5-ium thiocyanate
aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
1,1′-[5-Methyl-1-(4-methylphenyl)-1H-pyrazole-3,4-diyl)diethanone condenses with thiosemicarbazide in the presence of acetic acid to form the title salt, C15H17N4+·NCS−. The fused-ring system of the cation is almost planar (r.m.s. deviation = 0.020 Å) and the aromatic substituent is aligned at an angle of 48.2 (1)° with respect to the mean plane of the fused-ring system. The N atom at the 5-position is protonated and forms a N—H⋯N hydrogen bond to the thiocyanate cointer-ion.
Related literature
For reviews on pyrazolo-pyridazines, see: Akbas & Berber (2006); Matiichuk et al. (2009). For a related structure, see: Dinçer et al. (2004).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO (Agilent Technologies, 2010); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
https://doi.org/10.1107/S160053681004883X/bt5414sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681004883X/bt5414Isup2.hkl
1,1'-[5-Methyl-1-(4-tolyl)-1H-pyrazol-3,4-diyl)diethanone (0.26 g, 1 mmol) and thiosemicarbazide (0.18 g, 2 mmol) were heated in an ethanol/water (1/1, 50 ml) mixture for 4 h; acetic acid (0.5 ml) was added. The solid that separated on cooling was collected and recrystallized from ethanol to yield yellow prisms.
Carbon-bound H-atoms were placed in calculated positions (C–H 0.95–0.98 Å) and were included in the
in the riding model approximation, with Uiso(H) set to 1.2–1.5 times Ueq(C).The amino H-atom was located in a difference Fourier map and was freely refined.
As part of our studies on the pharmaceutical applications of pyrazole derivatives, we had intended to synthesis the thiosemicarbazide condensation product of the pyrazole-dialdeyde, 1,1'-[5-methyl-1-(4-tolyl)-1H-pyrazol-3,4-diyl)diethanone, but the reaction yielded instead a pyrazolo[3,4-d]pyridazine (Scheme I, Fig. 1). The reaction was probably catalyzed by acetic acid; the reaction involves a
followed by the formation of the thiocyanate ion (Fig. 2). The fused-ring system of the cation is planar (r.m.s. deviation 0.020 Å), and the aromatic substituent is aligned at 48.2 (1) ° with respect to the mean plane of the fused-ring. The nitrogen atom at the 5-position is protonated; the carbon–nitrogen double-bond involving the protonated nitrogen atom is somewhat longer [1.323 (2) Å] than the carbon–nitrogen double-bond involving the unprotonated one [1.310 (2) Å]. As the protonated nitrogen atom forms a hydrogen bond to the nitrogen end of the anion, the negative charge of the anion probably resides on this atom.Pyrazolo[3,4-d]pyridazines are more conveniently synthesized directly, from the reaction of 1H-pyrazole-3-carboxylic acids and
(Akbas & Berber, 2006). A review of their is given by Matiichuk et al. (2009). For the of a related compound, see: Dinçer et al. (2004).For reviews on pyrazolo-pyridazines, see: Akbas & Berber (2006); Matiichuk et al. (2009). For a related structure, see: Dinçer et al. (2004).
Data collection: CrysAlis PRO (Agilent Technologies, 2010); cell
CrysAlis PRO (Agilent Technologies, 2010); data reduction: CrysAlis PRO (Agilent Technologies, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).C15H17N4+·NCS− | F(000) = 1312 |
Mr = 311.41 | Dx = 1.328 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 4295 reflections |
a = 18.2445 (5) Å | θ = 2.2–29.3° |
b = 7.3341 (2) Å | µ = 0.21 mm−1 |
c = 24.2396 (8) Å | T = 100 K |
β = 106.121 (3)° | Prism, yellow |
V = 3115.89 (16) Å3 | 0.30 × 0.10 × 0.05 mm |
Z = 8 |
Agilent SuperNova diffractometer | 3491 independent reflections |
Radiation source: fine-focus sealed tube | 2968 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
Detector resolution: 10.4041 pixels mm-1 | θmax = 27.5°, θmin = 2.3° |
ω scans | h = −16→23 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent Technologies, 2010) | k = −9→9 |
Tmin = 0.939, Tmax = 0.990 | l = −31→23 |
7809 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.096 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.0472P)2 + 3.0958P] where P = (Fo2 + 2Fc2)/3 |
3491 reflections | (Δ/σ)max = 0.001 |
207 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
C15H17N4+·NCS− | V = 3115.89 (16) Å3 |
Mr = 311.41 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 18.2445 (5) Å | µ = 0.21 mm−1 |
b = 7.3341 (2) Å | T = 100 K |
c = 24.2396 (8) Å | 0.30 × 0.10 × 0.05 mm |
β = 106.121 (3)° |
Agilent SuperNova diffractometer | 3491 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Agilent Technologies, 2010) | 2968 reflections with I > 2σ(I) |
Tmin = 0.939, Tmax = 0.990 | Rint = 0.026 |
7809 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.096 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.32 e Å−3 |
3491 reflections | Δρmin = −0.27 e Å−3 |
207 parameters |
x | y | z | Uiso*/Ueq | ||
S1 | 0.41884 (2) | 1.03962 (5) | 0.678227 (15) | 0.01918 (11) | |
N1 | 0.30697 (7) | 0.87179 (17) | 0.44978 (5) | 0.0175 (3) | |
N2 | 0.37098 (7) | 0.79621 (17) | 0.43977 (5) | 0.0182 (3) | |
N3 | 0.28626 (6) | 0.74548 (16) | 0.28642 (5) | 0.0148 (2) | |
N4 | 0.21174 (6) | 0.79970 (16) | 0.26392 (5) | 0.0142 (2) | |
N5 | 0.33646 (8) | 0.96211 (19) | 0.56469 (6) | 0.0255 (3) | |
C1 | 0.43819 (8) | 0.6806 (2) | 0.37464 (6) | 0.0195 (3) | |
H1A | 0.4780 | 0.6633 | 0.4109 | 0.029* | |
H1B | 0.4564 | 0.7659 | 0.3502 | 0.029* | |
H1C | 0.4262 | 0.5632 | 0.3549 | 0.029* | |
C2 | 0.36843 (8) | 0.75572 (19) | 0.38665 (6) | 0.0156 (3) | |
C3 | 0.29986 (8) | 0.78638 (18) | 0.34177 (6) | 0.0146 (3) | |
C4 | 0.23596 (8) | 0.86541 (18) | 0.35465 (6) | 0.0146 (3) | |
C5 | 0.24134 (8) | 0.91093 (19) | 0.41184 (6) | 0.0164 (3) | |
C6 | 0.18028 (9) | 0.9977 (2) | 0.43299 (7) | 0.0221 (3) | |
H6A | 0.1980 | 1.0103 | 0.4749 | 0.033* | |
H6B | 0.1344 | 0.9214 | 0.4226 | 0.033* | |
H6C | 0.1684 | 1.1185 | 0.4155 | 0.033* | |
C7 | 0.17924 (8) | 0.87516 (19) | 0.30233 (6) | 0.0147 (3) | |
C8 | 0.10123 (8) | 0.9549 (2) | 0.28774 (6) | 0.0193 (3) | |
H8A | 0.0845 | 0.9835 | 0.2466 | 0.029* | |
H8B | 0.1019 | 1.0668 | 0.3100 | 0.029* | |
H8C | 0.0659 | 0.8671 | 0.2970 | 0.029* | |
C9 | 0.17735 (8) | 0.77377 (19) | 0.20373 (6) | 0.0144 (3) | |
C10 | 0.10569 (8) | 0.69513 (19) | 0.18460 (6) | 0.0165 (3) | |
H10 | 0.0803 | 0.6507 | 0.2112 | 0.020* | |
C11 | 0.07151 (8) | 0.68226 (19) | 0.12579 (6) | 0.0170 (3) | |
H11 | 0.0222 | 0.6295 | 0.1123 | 0.020* | |
C12 | 0.10849 (8) | 0.74559 (19) | 0.08639 (6) | 0.0165 (3) | |
C13 | 0.18234 (8) | 0.81476 (19) | 0.10713 (6) | 0.0158 (3) | |
H13 | 0.2092 | 0.8524 | 0.0807 | 0.019* | |
C14 | 0.21737 (8) | 0.82962 (19) | 0.16553 (6) | 0.0152 (3) | |
H14 | 0.2676 | 0.8769 | 0.1792 | 0.018* | |
C15 | 0.06899 (9) | 0.7449 (2) | 0.02308 (6) | 0.0218 (3) | |
H15A | 0.0200 | 0.6814 | 0.0161 | 0.033* | |
H15B | 0.1011 | 0.6822 | 0.0026 | 0.033* | |
H15C | 0.0602 | 0.8708 | 0.0092 | 0.033* | |
C16 | 0.37098 (8) | 0.9940 (2) | 0.61179 (6) | 0.0176 (3) | |
H1 | 0.3146 (11) | 0.898 (3) | 0.4877 (9) | 0.037 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.01806 (18) | 0.0235 (2) | 0.01600 (19) | −0.00002 (14) | 0.00481 (14) | −0.00172 (14) |
N1 | 0.0221 (6) | 0.0185 (6) | 0.0116 (6) | −0.0013 (5) | 0.0040 (5) | −0.0010 (5) |
N2 | 0.0195 (6) | 0.0184 (6) | 0.0159 (6) | −0.0008 (5) | 0.0035 (5) | −0.0004 (5) |
N3 | 0.0133 (5) | 0.0157 (6) | 0.0141 (6) | −0.0002 (5) | 0.0015 (4) | 0.0008 (5) |
N4 | 0.0144 (5) | 0.0142 (5) | 0.0134 (6) | −0.0009 (5) | 0.0030 (4) | −0.0001 (5) |
N5 | 0.0310 (7) | 0.0304 (7) | 0.0158 (7) | −0.0012 (6) | 0.0078 (5) | −0.0009 (6) |
C1 | 0.0170 (7) | 0.0225 (7) | 0.0172 (7) | 0.0005 (6) | 0.0018 (5) | −0.0019 (6) |
C2 | 0.0171 (7) | 0.0142 (7) | 0.0143 (7) | −0.0026 (6) | 0.0026 (5) | 0.0002 (5) |
C3 | 0.0175 (7) | 0.0124 (6) | 0.0142 (7) | −0.0024 (5) | 0.0045 (5) | 0.0002 (5) |
C4 | 0.0171 (6) | 0.0125 (6) | 0.0141 (7) | −0.0016 (5) | 0.0040 (5) | −0.0001 (5) |
C5 | 0.0201 (7) | 0.0141 (6) | 0.0150 (7) | −0.0019 (6) | 0.0050 (5) | 0.0010 (5) |
C6 | 0.0261 (8) | 0.0248 (8) | 0.0175 (7) | 0.0029 (6) | 0.0094 (6) | −0.0016 (6) |
C7 | 0.0184 (7) | 0.0125 (6) | 0.0136 (7) | −0.0016 (5) | 0.0053 (5) | −0.0005 (5) |
C8 | 0.0184 (7) | 0.0221 (8) | 0.0169 (7) | 0.0027 (6) | 0.0040 (6) | −0.0007 (6) |
C9 | 0.0173 (6) | 0.0138 (6) | 0.0112 (6) | 0.0015 (5) | 0.0024 (5) | 0.0003 (5) |
C10 | 0.0182 (7) | 0.0166 (7) | 0.0152 (7) | −0.0011 (6) | 0.0054 (5) | 0.0012 (5) |
C11 | 0.0156 (6) | 0.0165 (7) | 0.0174 (7) | −0.0026 (6) | 0.0020 (5) | −0.0013 (6) |
C12 | 0.0189 (7) | 0.0153 (7) | 0.0146 (7) | 0.0025 (6) | 0.0036 (5) | −0.0003 (5) |
C13 | 0.0178 (7) | 0.0169 (7) | 0.0141 (7) | 0.0021 (6) | 0.0065 (5) | 0.0009 (5) |
C14 | 0.0137 (6) | 0.0144 (7) | 0.0173 (7) | 0.0001 (5) | 0.0042 (5) | −0.0007 (5) |
C15 | 0.0223 (7) | 0.0269 (8) | 0.0143 (7) | 0.0006 (6) | 0.0018 (6) | 0.0006 (6) |
C16 | 0.0198 (7) | 0.0170 (7) | 0.0189 (7) | 0.0010 (6) | 0.0105 (6) | 0.0020 (6) |
S1—C16 | 1.6390 (15) | C6—H6B | 0.9800 |
N1—C5 | 1.3229 (18) | C6—H6C | 0.9800 |
N1—N2 | 1.3738 (17) | C7—C8 | 1.4877 (19) |
N1—H1 | 0.91 (2) | C8—H8A | 0.9800 |
N2—C2 | 1.3097 (18) | C8—H8B | 0.9800 |
N3—C3 | 1.3293 (18) | C8—H8C | 0.9800 |
N3—N4 | 1.3755 (16) | C9—C10 | 1.386 (2) |
N4—C7 | 1.3533 (17) | C9—C14 | 1.3905 (19) |
N4—C9 | 1.4320 (17) | C10—C11 | 1.3915 (19) |
N5—C16 | 1.164 (2) | C10—H10 | 0.9500 |
C1—C2 | 1.4879 (19) | C11—C12 | 1.393 (2) |
C1—H1A | 0.9800 | C11—H11 | 0.9500 |
C1—H1B | 0.9800 | C12—C13 | 1.396 (2) |
C1—H1C | 0.9800 | C12—C15 | 1.5034 (19) |
C2—C3 | 1.4294 (19) | C13—C14 | 1.3863 (19) |
C3—C4 | 1.4124 (19) | C13—H13 | 0.9500 |
C4—C7 | 1.3984 (19) | C14—H14 | 0.9500 |
C4—C5 | 1.4025 (19) | C15—H15A | 0.9800 |
C5—C6 | 1.492 (2) | C15—H15B | 0.9800 |
C6—H6A | 0.9800 | C15—H15C | 0.9800 |
C5—N1—N2 | 127.91 (12) | N4—C7—C8 | 124.77 (12) |
C5—N1—H1 | 120.8 (12) | C4—C7—C8 | 130.84 (13) |
N2—N1—H1 | 111.3 (12) | C7—C8—H8A | 109.5 |
C2—N2—N1 | 117.73 (12) | C7—C8—H8B | 109.5 |
C3—N3—N4 | 102.82 (11) | H8A—C8—H8B | 109.5 |
C7—N4—N3 | 114.78 (11) | C7—C8—H8C | 109.5 |
C7—N4—C9 | 127.13 (12) | H8A—C8—H8C | 109.5 |
N3—N4—C9 | 118.08 (11) | H8B—C8—H8C | 109.5 |
C2—C1—H1A | 109.5 | C10—C9—C14 | 121.39 (13) |
C2—C1—H1B | 109.5 | C10—C9—N4 | 120.13 (12) |
H1A—C1—H1B | 109.5 | C14—C9—N4 | 118.48 (12) |
C2—C1—H1C | 109.5 | C9—C10—C11 | 118.94 (13) |
H1A—C1—H1C | 109.5 | C9—C10—H10 | 120.5 |
H1B—C1—H1C | 109.5 | C11—C10—H10 | 120.5 |
N2—C2—C3 | 119.82 (13) | C12—C11—C10 | 121.00 (13) |
N2—C2—C1 | 118.53 (12) | C12—C11—H11 | 119.5 |
C3—C2—C1 | 121.65 (13) | C10—C11—H11 | 119.5 |
N3—C3—C4 | 112.43 (12) | C11—C12—C13 | 118.48 (13) |
N3—C3—C2 | 127.69 (13) | C11—C12—C15 | 120.84 (13) |
C4—C3—C2 | 119.87 (13) | C13—C12—C15 | 120.65 (13) |
C7—C4—C5 | 135.66 (13) | C14—C13—C12 | 121.43 (13) |
C7—C4—C3 | 105.60 (12) | C14—C13—H13 | 119.3 |
C5—C4—C3 | 118.72 (12) | C12—C13—H13 | 119.3 |
N1—C5—C4 | 115.91 (13) | C13—C14—C9 | 118.58 (13) |
N1—C5—C6 | 118.14 (13) | C13—C14—H14 | 120.7 |
C4—C5—C6 | 125.95 (13) | C9—C14—H14 | 120.7 |
C5—C6—H6A | 109.5 | C12—C15—H15A | 109.5 |
C5—C6—H6B | 109.5 | C12—C15—H15B | 109.5 |
H6A—C6—H6B | 109.5 | H15A—C15—H15B | 109.5 |
C5—C6—H6C | 109.5 | C12—C15—H15C | 109.5 |
H6A—C6—H6C | 109.5 | H15A—C15—H15C | 109.5 |
H6B—C6—H6C | 109.5 | H15B—C15—H15C | 109.5 |
N4—C7—C4 | 104.34 (12) | N5—C16—S1 | 179.46 (14) |
C5—N1—N2—C2 | −0.3 (2) | C9—N4—C7—C4 | 179.09 (12) |
C3—N3—N4—C7 | 1.25 (15) | N3—N4—C7—C8 | 175.84 (12) |
C3—N3—N4—C9 | −179.52 (11) | C9—N4—C7—C8 | −3.3 (2) |
N1—N2—C2—C3 | −1.58 (19) | C5—C4—C7—N4 | −177.34 (15) |
N1—N2—C2—C1 | 177.60 (12) | C3—C4—C7—N4 | 1.48 (15) |
N4—N3—C3—C4 | −0.19 (15) | C5—C4—C7—C8 | 5.3 (3) |
N4—N3—C3—C2 | 178.40 (13) | C3—C4—C7—C8 | −175.91 (14) |
N2—C2—C3—N3 | −176.53 (13) | C7—N4—C9—C10 | −48.7 (2) |
C1—C2—C3—N3 | 4.3 (2) | N3—N4—C9—C10 | 132.23 (13) |
N2—C2—C3—C4 | 2.0 (2) | C7—N4—C9—C14 | 131.16 (15) |
C1—C2—C3—C4 | −177.20 (13) | N3—N4—C9—C14 | −47.96 (17) |
N3—C3—C4—C7 | −0.83 (16) | C14—C9—C10—C11 | −3.9 (2) |
C2—C3—C4—C7 | −179.55 (12) | N4—C9—C10—C11 | 175.90 (12) |
N3—C3—C4—C5 | 178.22 (12) | C9—C10—C11—C12 | 0.5 (2) |
C2—C3—C4—C5 | −0.5 (2) | C10—C11—C12—C13 | 3.0 (2) |
N2—N1—C5—C4 | 1.7 (2) | C10—C11—C12—C15 | −175.17 (13) |
N2—N1—C5—C6 | −178.41 (13) | C11—C12—C13—C14 | −3.3 (2) |
C7—C4—C5—N1 | 177.48 (15) | C15—C12—C13—C14 | 174.88 (13) |
C3—C4—C5—N1 | −1.22 (19) | C12—C13—C14—C9 | 0.0 (2) |
C7—C4—C5—C6 | −2.4 (3) | C10—C9—C14—C13 | 3.6 (2) |
C3—C4—C5—C6 | 178.94 (13) | N4—C9—C14—C13 | −176.18 (12) |
N3—N4—C7—C4 | −1.76 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···N5 | 0.91 (2) | 1.86 (2) | 2.7668 (18) | 175.6 (19) |
Experimental details
Crystal data | |
Chemical formula | C15H17N4+·NCS− |
Mr | 311.41 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 100 |
a, b, c (Å) | 18.2445 (5), 7.3341 (2), 24.2396 (8) |
β (°) | 106.121 (3) |
V (Å3) | 3115.89 (16) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.21 |
Crystal size (mm) | 0.30 × 0.10 × 0.05 |
Data collection | |
Diffractometer | Agilent SuperNova |
Absorption correction | Multi-scan (CrysAlis PRO; Agilent Technologies, 2010) |
Tmin, Tmax | 0.939, 0.990 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7809, 3491, 2968 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.096, 1.00 |
No. of reflections | 3491 |
No. of parameters | 207 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.32, −0.27 |
Computer programs: CrysAlis PRO (Agilent Technologies, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···N5 | 0.91 (2) | 1.86 (2) | 2.7668 (18) | 175.6 (19) |
Acknowledgements
We thank King Saud University and the University of Malaya for supporting this study.
References
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As part of our studies on the pharmaceutical applications of pyrazole derivatives, we had intended to synthesis the thiosemicarbazide condensation product of the pyrazole-dialdeyde, 1,1'-[5-methyl-1-(4-tolyl)-1H-pyrazol-3,4-diyl)diethanone, but the reaction yielded instead a pyrazolo[3,4-d]pyridazine (Scheme I, Fig. 1). The reaction was probably catalyzed by acetic acid; the reaction involves a cyclization followed by the formation of the thiocyanate ion (Fig. 2). The fused-ring system of the cation is planar (r.m.s. deviation 0.020 Å), and the aromatic substituent is aligned at 48.2 (1) ° with respect to the mean plane of the fused-ring. The nitrogen atom at the 5-position is protonated; the carbon–nitrogen double-bond involving the protonated nitrogen atom is somewhat longer [1.323 (2) Å] than the carbon–nitrogen double-bond involving the unprotonated one [1.310 (2) Å]. As the protonated nitrogen atom forms a hydrogen bond to the nitrogen end of the anion, the negative charge of the anion probably resides on this atom.
Pyrazolo[3,4-d]pyridazines are more conveniently synthesized directly, from the reaction of 1H-pyrazole-3-carboxylic acids and hydrazines (Akbas & Berber, 2006). A review of their molecular design is given by Matiichuk et al. (2009). For the crystal structure of a related compound, see: Dinçer et al. (2004).