research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Synthesis, crystal structure and Hirshfeld surface analysis of 5-methyl-1H-pyrazol-3-yl 4-nitro­benzene­sulfonate at 90 K

crossmark logo

aDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysuru-570 006, India, bDepartment of Physical Sciences, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Bengaluru-560 035, India, cDepartment of Chemistry, T. John Institute of Technology, Bengaluru-560 083, India, and dDepartment of Chemistry, University of Kentucky, Lexington, KY, 40506-0055, USA
*Correspondence e-mail: yathirajan@hotmail.com

Edited by X. Hao, Institute of Chemistry, Chinese Academy of Sciences (Received 19 November 2024; accepted 23 November 2024; online 28 November 2024)

This study presents the synthesis, crystal structure, and a Hirshfeld-surface analysis of the bioactive compound 5-methyl-1H-pyrazol-3-yl 4-nitro­benzene­sulfonate­(C10H9N3O5S), a pyrazole derivative with pharmacological potential. Pyrazoles are known for diverse bioactivities, and recent research emphasizes their role as a ‘privileged structure’ in drug design. Here, the asymmetric unit of the title compound contains two distinct mol­ecules, A and B, exhibiting differences in conformation resulting from variation in key torsion angles. These distinctions influence the mol­ecular orientation and inter­molecular inter­actions, with strong N—H⋯N and N—H⋯O hydrogen bonds forming a centrosymmetric tetra­mer stabilized by ππ stacking. Hirshfeld surface analysis readily confirms differing inter­molecular contacts for A and B, primarily involving hydrogen atoms and differences in their close contacts to nitro­gen and oxygen. This study offers further insight into the mol­ecular architecture and potential inter­actions of pyrazole-based drug candidates.

1. Chemical context

Pyrazoles exhibit diverse pharmacological activities, including protein glycation inhibition, anti­bacterial, anti­fungal, anti­cancer, anti­depressant, anti-inflammatory, anti­tubercular, anti­oxidant, and anti­viral effects (Fustero et al., 2011[Fustero, S., Sánchez-Roselló, M., Barrio, P. & Simón-Fuentes, A. (2011). Chem. Rev. 111, 6984-7034.]; Steinbach et al., 2000[Steinbach, G., Lynch, P. M., Phillips, R. K. S., Wallace, M. H., Hawk, E., Gordon, G. B., Wakabayashi, N., Saunders, B., Shen, Y., Fujimura, T., Su, L.-K., Levin, B., Godio, L., Patterson, S., Rodriguez-Bigas, M. A., Jester, S. L., King, K. L., Schumacher, M., Abbruzzese, J., DuBois, R. N., Hittelman, W. N., Zimmerman, S., Sherman, J. W. & Kelloff, G. (2000). N. Engl. J. Med. 342, 1946-1952.]; García-Lozano et al., 1997[García-Lozano, J., Server-Carrió, J., Escrivà, E., Folgado, J.-V., Molla, C. & Lezama, L. (1997). Polyhedron, 16, 939-944.]). Naim et al. (2016[Naim, M. J., Alam, O., Nawaz, F., Alam, M. J. & Alam, P. (2016). J. Pharm. Bioallied Sci. 8, 2-17.]) provide an overview of the current status of pyrazoles and their biological activities. Various reviews focus on bioactive pyrazole derivatives (Ansari et al., 2017[Ansari, A., Ali, A., Asif, M. & Shamsuzzaman, S. (2017). New J. Chem. 41, 16-41.]), synthetic and biological attributes of pyrazole compounds (Dwivedi et al., 2018[Dwivedi, J., Sharma, S., Jain, S. & Singh, A. (2018). Mini Rev. Med. Chem. 18, 918-947.]), and the role of the pyrazole moiety in drug development as a ‘privileged structure’ (Faria et al., 2017[Faria, J. V., Vegi, P. F., Miguita, A. G. C., dos Santos, M. S., Boechat, N. & Bernardino, A. M. R. (2017). Bioorg. Med. Chem. 25, 5891-5903.]; Patil, 2020[Patil, S. B. (2020). J. Pharm. Sci. Res. 12, 402-404.]; Yet, 2018[Yet, L. (2018). Methods and Principles in Medicinal Chemistry. London, Hoboken, NJ: John Wiley & Sons.]). Comprehensive reviews on pyrazole synthesis and pharmacology are available, highlighting recent advances (Karrouchi et al., 2018[Karrouchi, K., Radi, S., Ramli, Y., Taoufik, J., Mabkhot, Y. N., Al-aizari, F. A. & Ansar, M. (2018). Molecules, 23, 134.]; Fustero et al., 2009[Fustero, S., Simón-Fuentes, A. & Sanz-Cervera, J. F. (2009). Org. Prep. Proced. Int. 41, 253-290.]; Ebenezer et al., 2022[Ebenezer, O., Shapi, M. & Tuszynski, J. A. (2022). Biomedicines 10, 1124.]).

Several crystal structures of pyrazole derivatives have been reported, including 1,3-diphenyl-4,5-di­hydro-1H-pyrazol-5-one (Baddeley et al., 2012[Baddeley, T. C., Wardell, S. M. S. V., Tiekink, E. R. T. & Wardell, J. L. (2012). Acta Cryst. E68, o1016-o1017.]), 1-aryl-1H-pyrazole-3,4-di­carboxyl­ate derivatives (Asma et al., 2018[Asma, Kalluraya, B., Yathirajan, H. S., Rathore, R. S. & Glidewell, C. (2018). Acta Cryst. E74, 1783-1789.]), and additional complex pyrazole compounds (Archana et al., 2022[Archana, S. D., Nagma Banu, H. A., Kalluraya, B., Yathirajan, H. S., Balerao, R. & Butcher, R. J. (2022). IUCrData, 7, x220924.]; Priyanka et al., 2022[Priyanka, P., Jayanna, B. K., Sunil Kumar, Y. C., Shreenivas, M. T., Srinivasa, G. R., Divakara, T. R., Yathirajan, H. S. & Parkin, S. (2022). Acta Cryst. E78, 1084-1088.]; Pintro et al., 2022[Pintro, C. J., Long, A. K., Amonette, A. J., Lobue, J. M. & Padgett, C. W. (2022). Acta Cryst. E78, 336-339.]; Metwally et al., 2021[Metwally, N. H., Elgemeie, G. H. & Jones, P. G. (2021). Acta Cryst. E77, 1054-1057.]). Related structures, such as 5-methyl-1-[(4-methyl­phen­yl)sulfon­yl]-1H-pyrazol-3-yl 4-methyl­benzene­sulfonate (XEBLOH) and 1-(4-methyl­phen­yl)-3-phenyl-1H-pyrazol-5-yl 4-nitro­benzene­sulfonate, have also been described (Murtaza et al., 2012[Murtaza, S., Kausar, N., Tahir, M. N., Tariq, J. & Bibi, S. (2012). Acta Cryst. E68, o2196.]; Wardell et al., 2012[Wardell, S. M. S. V., Tiekink, E. R. T. & Wardell, J. L. (2012). Acta Cryst. E68, o1086-o1087.]).

Given the significance of pyrazoles and specifically 5-methyl-1H-pyrazol-3-yl 4-nitro­benzene­sulfonate, this paper presents the crystal-structure analysis of the title compound, C10H9N3O5S, I.

[Scheme 1]

2. Structural commentary

The mol­ecular structure of I features a 4-nitro­benzene ring bonded to a sulfonate sulfur atom, along with a 3-methyl-1H-pyrazole ring attached to the single-bonded oxygen atom of the sulfonate group. The asymmetric unit comprises two crystallographically distinct mol­ecules, A and B (Fig. 1[link]). While both mol­ecules exhibit typical bond lengths and angles, their overall conformations differ. The primary distinctions are in the torsion angles N1—C1—O1—S1, C1—O1—S1—C5, and O1—S1—C5—C6, which are 88.97 (12), 64.92 (9), and 78.91 (10)° for mol­ecule A, and 83.78 (12), −83.75 (9), and 95.42 (10)° for mol­ecule B. These torsional variations lead to differences in the relative proximity and orientation of the pyrazole and benzene rings in each mol­ecule. This is shown in a least-squares fit overlay plot (Fig. 2[link]) and qu­anti­fied in Table 1[link]. The only other intra­molecular degree of freedom lies in the rotation of the NO2 groups relative to their attached benzene rings. For mol­ecule A, this dihedral angle is 1.37 (10)°, i.e. nearly coplanar, while in mol­ecule B, it is slightly larger at 6.78 (4)°. There are no intra­molecular hydrogen bonds of any type in either mol­ecule A or B.

Table 1
Conformation-dependant angles and distances (Å, °) in I

Torsion angle Mol­ecule A Mol­ecule B
N1—C1—O1—S1 88.97 (12) 83.78 (12)
C1—O1—S1—C5 64.92 (9) −83.75 (9)
O1—S1—C5—C6 78.91 (10) 95.42 (10)
C7—C8—N3—O5 −0.50 (17) −6.06 (17)
     
Dihedral anglea    
bz/nitro 1.37 (10) 6.78 (4)
bz/pz 43.10 (4) 37.22 (5)
     
Centroid⋯centroida    
Cg(bz)⋯Cg(pz) 4.505 (1)b 4.936 (1)b
Notes: (a) Abbreviations: bz = benzene; pz = pyrazole; Cg = centroid. (b) These distances do not imply any overlap, they merely show that the rings in A are closer than those in B.
[Figure 1]
Figure 1
An ellipsoid plot of I (50% probability) showing the two crystallographically independent mol­ecules (suffixes A and B). Hydrogen atoms are shown as arbitrary circles.
[Figure 2]
Figure 2
Least-squares overlay of the two mol­ecules of I, aligning the benzene rings and the sulfur atom of the sulfonyl group. The coordinates of B were inverted for optimal alignment.

3. Supra­molecular features

In I, there are only two strong inter­molecular hydrogen bonds: N2A—H2A⋯N1B [dDA = 2.9063 (15) Å] and N2B—H2B⋯O4Ai [dDA = 2.9630 (15) Å; symmetry operation: (i) −x, −y + 1, −z + 1], Table 2[link]. The former connects the two mol­ecules within the chosen asymmetric unit, while the latter generates a centrosymmetric tetra­mer (i.e., a pair of pairs), as shown in Fig. 3[link]. The integrity of this tetra­mer is augmented by a pair of ππ stacking inter­actions that superimpose the pyrazole ring of mol­ecule A with the benzene ring of B (plus the equivalent inter­action – symmetry operation i, above), CgCg = 3.524 (1) Å. These tetra­mers stack into columns that propagate parallel to the a-axis. In addition, there are a number of weaker hydrogen-bond-type inter­actions of the C—H⋯O form that connect these columns in both the b- and c-axis directions. The different inter­molecular contacts experienced by mol­ecules A and B are readily apparent in Hirshfeld surface fingerprint plots (CrystalExplorer21, Spackman et al., 2021[Spackman, P. R., Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Jayatilaka, D. & Spackman, M. A. (2021). J. Appl. Cryst. 54, 1006-1011.]). These are shown in Fig. 4[link] for mol­ecules A and B calculated individually, but presented side-by-side for ease of comparison. While it is clear from Fig. 4[link]a,b that most inter­molecular contacts involve hydrogen atoms (56.9% and 50.5% for A and B, respectively), the distributions are different. For A, there are no short contacts to oxygen atoms on adjacent mol­ecules (Fig. 4[link]c), whereas for B there are (note the sharp blue spike in Fig. 4[link]d). The situation is reversed for contacts to nitro­gen on adjacent mol­ecules (Fig. 4[link]e,f). This, of course, is simply a consequence of the different hydrogen-bonding modes of mol­ecules A and B. The only other types of contact with double-digit percentage coverage are those involving carbon atoms, which are similar, but not identical for A and B (Fig. 4[link]g,h).

Table 2
Hydrogen bonds and other close contacts (Å, °) in I

Hydrogen bonds        
D—H⋯A D—H H⋯A DA D—H⋯A
N2A—H2A⋯N1B 0.875 (17) 2.047 (17) 2.9063 (15) 167.0 (15)
N2B—H2B⋯O4Ai 0.853 (19) 2.121 (19) 2.9630 (15) 169.1 (16)
C2B—H2BA⋯O2Bii 0.95 2.63 3.3452 (15) 132.1
C2B—H2BA⋯O4Biii 0.95 2.66 3.5201 (15) 151.4
C4B—H4BC⋯O5Biii 0.98 2.60 3.5814 (17) 176.8
C6B—H6B⋯O3Biv 0.95 2.48 3.3910 (15) 160.1
C7B—H7B⋯O2Bv 0.95 2.39 3.1622 (15) 137.6
C10B—H10B⋯O5Bv 0.95 2.54 3.3418 (16) 142.0
         
ππ stacks        
Ring 1⋯ring 2   Distance Dihedral  
Cg(pzA)⋯Cg(bzB)   3.524 (1) 5.41 (4)  
Abbreviations: Cg = centroid; bz = benzene; pz = pyrazole. Symmetry codes: (i) −x, −y + 1, −z + 1; (ii) −x + 2, −y, −z + 2; (iii) x + 1, y − 1, z; (iv) −x + 1, −y, −z + 2; (v) x − 1, y, z; (vi) x + 1, y, z.
[Figure 3]
Figure 3
A partial packing plot viewed approximately down the a axis. Hydrogen bonds are drawn as thick dashed lines and ππ overlap is shown as thin dashed lines between ring centroids. The whole construct forms a centrosymmetric tetra­mer.
[Figure 4]
Figure 4
Hirshfeld surface (HS) fingerprint plots calculated independently for mol­ecules A and B. Panels (a) and (b) compare contacts between the whole of mol­ecule A within its own Hirshfeld surface and hydrogen atoms outside the HS, and vice versa. Panels (c) and (d) show analogous contacts to oxygen atoms, (e) and (f) show the corresponding plots to nitro­gen, while (g) and (h) show contacts to carbon.

4. Database survey

A search of the CSD (v5.45 with updates to September 2024; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) of I with the nitro and methyl groups removed gave no hits. With the N—H hydrogen also removed, the search returned a single match, 5-methyl-1-[(4-methyl­phen­yl)sulfon­yl]-1H-pyrazol-3-yl-4-methyl­benzene sulfonate (CSD refcode XEBLOH; Murtaza et al., 2012[Murtaza, S., Kausar, N., Tahir, M. N., Tariq, J. & Bibi, S. (2012). Acta Cryst. E68, o2196.]). A search target of 4-nitro­benzene­sulfonate gave 95 hits whereas a search fragment of pyrazol-3-yl sulfonate gave two hits, XEBLOH again, and EBAQUX (Kim et al., 2018[Kim, Y., Kim, H., Lee, J., Lee, J. K., Min, S. J., Seong, J., Rhim, H., Tae, J., Lee, H. J. & Choo, H. (2018). J. Med. Chem. 61, 7218-7233.]), di-t-butyl 3-[(tri­fluoro­methane­sulfon­yl)­oxy]-4,5,7,8-tetra­hydro­pyrazolo­[3,4-d]azepine-1,6-di­carboxyl­ate, which has little else in common with I.

5. Synthesis and crystallization

An equimolar mixture (0.1 mol) of ethyl aceto­acetate (12.75 ml) and hydrazine hydrate (4.96 ml) in ethanol was stirred for 15–20 min. at room temperature, forming a white precipitate of pyrazolone. The precipitate was then separated by filtration and dried. The pyrazolone (1 g, 10.3 mmol) and 4-nitro­benzene­sulfonyl chloride (2.28 g, 10.3 mmol) were stirred in aceto­nitrile (25 ml) with tri­ethyl­amine for 30 min., turning the reaction mixture yellow–red. Stirring continued for approximately 5 h, with progress monitored by TLC (using hexane and di­chloro­methane as the mobile phase). After acidifying the mixture with 5% HCl, the solvent was evaporated. The product was extracted with ethyl acetate (3 × 15 ml), and the combined organic layers were dried over anhydrous sodium sulfate to yield the crude product, as summarized in Fig. 5[link]. Recrystallization by slow evaporation from a 1:1 aceto­nitrile–ethyl acetate mixture yielded orange–red crystals after one week.

[Figure 5]
Figure 5
Reaction scheme for the formation of I.

6. Refinement

Crystal data, data collection, and structure refinement details are given in Table 3[link]. All hydrogen atoms were found in difference-Fourier maps. The N—H hydrogens (i.e., H2A and H2B) were refined freely (x, y, z, Uij), but carbon-bound hydrogens were included using riding models, with constrained distances set to 0.95 Å (Csp2H) and 0.98 Å (RCH3). Uiso(H) parameters were set to values of either 1.2Ueq or 1.5Ueq (RCH3 only) of their attached atom.

Table 3
Experimental details

Crystal data
Chemical formula C10H9N3O5S
Mr 283.26
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 90
a, b, c (Å) 7.0823 (3), 11.7865 (6), 15.8999 (8)
α, β, γ (°) 68.340 (1), 81.516 (2), 76.435 (2)
V3) 1196.39 (10)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.29
Crystal size (mm) 0.28 × 0.21 × 0.14
 
Data collection
Diffractometer Bruker D8 Venture dual source
Absorption correction Multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.])
Tmin, Tmax 0.930, 0.971
No. of measured, independent and observed [I > 2σ(I)] reflections 43837, 5472, 4902
Rint 0.039
(sin θ/λ)max−1) 0.650
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.067, 1.04
No. of reflections 5472
No. of parameters 353
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.31, −0.42
Computer programs: APEX5 (Bruker, 2023[Bruker (2023). APEX5. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2019/3 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), XP in SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELX (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

5-Methyl-1H-pyrazol-3-yl 4-nitrobenzenesulfonate top
Crystal data top
C10H9N3O5SZ = 4
Mr = 283.26F(000) = 584
Triclinic, P1Dx = 1.573 Mg m3
a = 7.0823 (3) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.7865 (6) ÅCell parameters from 9613 reflections
c = 15.8999 (8) Åθ = 2.7–27.5°
α = 68.340 (1)°µ = 0.29 mm1
β = 81.516 (2)°T = 90 K
γ = 76.435 (2)°Solvent-rounded block, pale orange-brown
V = 1196.39 (10) Å30.28 × 0.21 × 0.14 mm
Data collection top
Bruker D8 Venture dual source
diffractometer
5472 independent reflections
Radiation source: microsource4902 reflections with I > 2σ(I)
Detector resolution: 7.41 pixels mm-1Rint = 0.039
φ and ω scansθmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
h = 89
Tmin = 0.930, Tmax = 0.971k = 1515
43837 measured reflectionsl = 2020
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)] = 0.027Hydrogen site location: mixed
wR(F2) = 0.067H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0199P)2 + 0.6984P]
where P = (Fo2 + 2Fc2)/3
5472 reflections(Δ/σ)max = 0.001
353 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = 0.42 e Å3
Special details top

Experimental. The crystal was mounted using polyisobutene oil on the tip of a fine glass fibre, which was fastened in a copper mounting pin with electrical solder. It was placed directly into the cold gas stream of a liquid-nitrogen based cryostat (Hope, 1994; Parkin & Hope, 1998).

Diffraction data were collected with the crystal at 90K, which is standard practice in this laboratory for the majority of flash-cooled crystals.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refinement progress was checked using PLATON (Spek, 2020) and by an R-tensor (Parkin, 2000). The final model was further checked with the IUCr utility checkCIF.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S1A0.65614 (4)0.71414 (3)0.53685 (2)0.01651 (7)
O1A0.57056 (13)0.67119 (8)0.64020 (6)0.01783 (18)
O2A0.75936 (13)0.60887 (9)0.51477 (6)0.0230 (2)
O3A0.75121 (13)0.81135 (9)0.53055 (6)0.0229 (2)
O4A0.13447 (15)0.85898 (10)0.31425 (7)0.0315 (2)
O5A0.16207 (15)1.02917 (10)0.34137 (7)0.0310 (2)
N1A0.55538 (15)0.45947 (10)0.70016 (7)0.0172 (2)
N2A0.40705 (15)0.39661 (10)0.72300 (7)0.0170 (2)
H2A0.434 (2)0.3155 (16)0.7480 (11)0.025 (4)*
N3A0.07568 (16)0.92479 (11)0.34531 (7)0.0230 (2)
C1A0.46349 (18)0.57635 (11)0.66818 (8)0.0153 (2)
C2A0.26185 (18)0.59134 (12)0.66978 (8)0.0182 (2)
H2AA0.1684670.6666420.6505950.022*
C3A0.23007 (18)0.47108 (12)0.70577 (8)0.0178 (2)
C4A0.0480 (2)0.42099 (14)0.7226 (1)0.0269 (3)
H4AA0.0101630.4224050.6653120.040*
H4AB0.0562850.4724410.7480790.040*
H4AC0.0704100.3351770.7654660.040*
C5A0.44319 (18)0.77770 (11)0.47720 (8)0.0162 (2)
C6A0.34479 (19)0.89710 (12)0.47076 (9)0.0202 (3)
H6A0.3936380.9441830.4968730.024*
C7A0.17492 (19)0.94661 (12)0.42591 (9)0.0213 (3)
H7A0.1061021.0285630.4195750.026*
C8A0.10808 (18)0.87335 (12)0.39054 (8)0.0186 (2)
C9A0.20361 (19)0.75461 (12)0.39659 (9)0.0208 (3)
H9A0.1532630.7073710.3711630.025*
C10A0.37520 (19)0.70585 (12)0.44076 (8)0.0189 (2)
H10A0.4449720.6244700.4459260.023*
S1B0.76662 (4)0.14007 (3)0.96788 (2)0.01521 (7)
O1B0.82898 (12)0.13255 (8)0.86847 (6)0.01669 (18)
O2B0.92921 (13)0.17288 (9)0.98930 (7)0.0225 (2)
O3B0.69677 (13)0.03131 (8)1.02475 (6)0.01977 (19)
O4B0.15018 (15)0.68014 (9)0.87210 (8)0.0308 (2)
O5B0.05168 (13)0.55827 (9)0.89274 (7)0.0251 (2)
N1B0.55988 (15)0.13086 (9)0.79934 (7)0.0161 (2)
N2B0.50809 (16)0.04466 (10)0.77422 (7)0.0166 (2)
H2B0.400 (3)0.0622 (16)0.7499 (12)0.033 (5)*
N3B0.11314 (16)0.57702 (10)0.89035 (7)0.0197 (2)
C1B0.72563 (17)0.07052 (11)0.83722 (8)0.0144 (2)
C2B0.78320 (18)0.05058 (11)0.83709 (8)0.0171 (2)
H2BA0.8968630.1097160.8600150.020*
C3B0.63631 (19)0.06460 (11)0.79581 (8)0.0177 (2)
C4B0.6056 (2)0.17205 (13)0.77508 (10)0.0278 (3)
H4BA0.6216480.1534370.7093560.042*
H4BB0.4738230.1870070.7972780.042*
H4BC0.7010400.2464130.8049560.042*
C5B0.57217 (17)0.26894 (11)0.94752 (8)0.0143 (2)
C6B0.38283 (18)0.24866 (11)0.95975 (8)0.0162 (2)
H6B0.3581370.1666060.9799400.019*
C7B0.23122 (18)0.35076 (11)0.94185 (8)0.0170 (2)
H7B0.0999370.3403640.9499660.020*
C8B0.27494 (18)0.46842 (11)0.91184 (8)0.0161 (2)
C9B0.46244 (18)0.48948 (11)0.89999 (8)0.0173 (2)
H9B0.4865320.5716720.8798630.021*
C10B0.61422 (18)0.38741 (11)0.91830 (8)0.0168 (2)
H10B0.7451780.3981870.9109920.020*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S1A0.01586 (14)0.01781 (15)0.01583 (15)0.00515 (11)0.00157 (11)0.00453 (11)
O1A0.0224 (4)0.0181 (4)0.0148 (4)0.0083 (3)0.0019 (3)0.0050 (3)
O2A0.0208 (5)0.0244 (5)0.0230 (5)0.0009 (4)0.0012 (4)0.0094 (4)
O3A0.0215 (5)0.0239 (5)0.0241 (5)0.0108 (4)0.0031 (4)0.0048 (4)
O4A0.0260 (5)0.0421 (6)0.0315 (6)0.0058 (5)0.0115 (4)0.0157 (5)
O5A0.0240 (5)0.0300 (5)0.0335 (6)0.0023 (4)0.0068 (4)0.0075 (5)
N1A0.0177 (5)0.0177 (5)0.0162 (5)0.0041 (4)0.0016 (4)0.0054 (4)
N2A0.0192 (5)0.0135 (5)0.0177 (5)0.0039 (4)0.0018 (4)0.0041 (4)
N3A0.0180 (5)0.0302 (6)0.0180 (5)0.0045 (5)0.0015 (4)0.0051 (5)
C1A0.0193 (6)0.0151 (6)0.0125 (5)0.0054 (5)0.0017 (4)0.0046 (4)
C2A0.0180 (6)0.0168 (6)0.0177 (6)0.0009 (5)0.0034 (5)0.0042 (5)
C3A0.0177 (6)0.0201 (6)0.0157 (6)0.0042 (5)0.0022 (5)0.0057 (5)
C4A0.0228 (7)0.0292 (7)0.0297 (7)0.0109 (6)0.0018 (6)0.0080 (6)
C5A0.0171 (6)0.0178 (6)0.0130 (5)0.0058 (5)0.0003 (4)0.0033 (5)
C6A0.0208 (6)0.0185 (6)0.0234 (6)0.0071 (5)0.0025 (5)0.0072 (5)
C7A0.0202 (6)0.0176 (6)0.0244 (7)0.0034 (5)0.0015 (5)0.0054 (5)
C8A0.0155 (6)0.0247 (6)0.0139 (6)0.0052 (5)0.0016 (4)0.0037 (5)
C9A0.0233 (6)0.0249 (7)0.0175 (6)0.0067 (5)0.0034 (5)0.0093 (5)
C10A0.0223 (6)0.0182 (6)0.0171 (6)0.0036 (5)0.0022 (5)0.0072 (5)
S1B0.01556 (14)0.01389 (14)0.01669 (15)0.00051 (11)0.00472 (11)0.00597 (11)
O1B0.0154 (4)0.0182 (4)0.0190 (4)0.0045 (3)0.0003 (3)0.0090 (3)
O2B0.0192 (4)0.0218 (5)0.0308 (5)0.0003 (4)0.0104 (4)0.0131 (4)
O3B0.0245 (5)0.0140 (4)0.0180 (4)0.0009 (3)0.0030 (4)0.0035 (3)
O4B0.0298 (5)0.0151 (5)0.0473 (6)0.0016 (4)0.0057 (5)0.0130 (4)
O5B0.0169 (4)0.0256 (5)0.0314 (5)0.0016 (4)0.0046 (4)0.0106 (4)
N1B0.0174 (5)0.0139 (5)0.0170 (5)0.0029 (4)0.0024 (4)0.0053 (4)
N2B0.0181 (5)0.0151 (5)0.0172 (5)0.0030 (4)0.0049 (4)0.0050 (4)
N3B0.0199 (5)0.0171 (5)0.0216 (5)0.0006 (4)0.0022 (4)0.0085 (4)
C1B0.0155 (5)0.0148 (6)0.0131 (5)0.0036 (4)0.0007 (4)0.0048 (4)
C2B0.0189 (6)0.0143 (6)0.0164 (6)0.0001 (5)0.0036 (5)0.0046 (5)
C3B0.0230 (6)0.0136 (6)0.0158 (6)0.0024 (5)0.0034 (5)0.0042 (5)
C4B0.0356 (8)0.0180 (6)0.0334 (8)0.0036 (6)0.0115 (6)0.0104 (6)
C5B0.0158 (6)0.0142 (5)0.0133 (5)0.0009 (4)0.0024 (4)0.0058 (4)
C6B0.0192 (6)0.0142 (6)0.0155 (6)0.0049 (5)0.0002 (5)0.0048 (5)
C7B0.0146 (6)0.0188 (6)0.0184 (6)0.0040 (5)0.0001 (5)0.0075 (5)
C8B0.0179 (6)0.0151 (6)0.0148 (6)0.0006 (5)0.0018 (4)0.0066 (5)
C9B0.0219 (6)0.0139 (6)0.0170 (6)0.0050 (5)0.0014 (5)0.0055 (5)
C10B0.0167 (6)0.0173 (6)0.0179 (6)0.0047 (5)0.0015 (5)0.0070 (5)
Geometric parameters (Å, º) top
S1A—O2A1.4204 (10)S1B—O2B1.4190 (9)
S1A—O3A1.4260 (9)S1B—O3B1.4197 (9)
S1A—O1A1.6001 (9)S1B—O1B1.6063 (9)
S1A—C5A1.7615 (13)S1B—C5B1.7595 (12)
O1A—C1A1.3977 (14)O1B—C1B1.3941 (14)
O4A—N3A1.2304 (15)O4B—N3B1.2235 (14)
O5A—N3A1.2220 (15)O5B—N3B1.2306 (14)
N1A—C1A1.3190 (16)N1B—C1B1.3220 (16)
N1A—N2A1.3559 (14)N1B—N2B1.3578 (14)
N2A—C3A1.3506 (16)N2B—C3B1.3483 (16)
N2A—H2A0.875 (17)N2B—H2B0.853 (19)
N3A—C8A1.4706 (16)N3B—C8B1.4741 (15)
C1A—C2A1.3948 (17)C1B—C2B1.3902 (16)
C2A—C3A1.3785 (17)C2B—C3B1.3793 (18)
C2A—H2AA0.9500C2B—H2BA0.9500
C3A—C4A1.4905 (18)C3B—C4B1.4896 (18)
C4A—H4AA0.9800C4B—H4BA0.9800
C4A—H4AB0.9800C4B—H4BB0.9800
C4A—H4AC0.9800C4B—H4BC0.9800
C5A—C10A1.3858 (17)C5B—C10B1.3891 (17)
C5A—C6A1.3898 (17)C5B—C6B1.3901 (17)
C6A—C7A1.3831 (18)C6B—C7B1.3833 (17)
C6A—H6A0.9500C6B—H6B0.9500
C7A—C8A1.3838 (18)C7B—C8B1.3842 (17)
C7A—H7A0.9500C7B—H7B0.9500
C8A—C9A1.3789 (18)C8B—C9B1.3809 (17)
C9A—C10A1.3880 (18)C9B—C10B1.3838 (17)
C9A—H9A0.9500C9B—H9B0.9500
C10A—H10A0.9500C10B—H10B0.9500
O2A—S1A—O3A120.96 (6)O2B—S1B—O3B121.47 (6)
O2A—S1A—O1A110.09 (5)O2B—S1B—O1B103.47 (5)
O3A—S1A—O1A102.91 (5)O3B—S1B—O1B109.58 (5)
O2A—S1A—C5A109.10 (6)O2B—S1B—C5B108.75 (6)
O3A—S1A—C5A109.78 (6)O3B—S1B—C5B109.18 (6)
O1A—S1A—C5A102.30 (5)O1B—S1B—C5B102.69 (5)
C1A—O1A—S1A117.15 (7)C1B—O1B—S1B117.88 (7)
C1A—N1A—N2A102.28 (10)C1B—N1B—N2B102.55 (10)
C3A—N2A—N1A113.71 (10)C3B—N2B—N1B113.21 (10)
C3A—N2A—H2A127.6 (11)C3B—N2B—H2B127.3 (12)
N1A—N2A—H2A118.7 (11)N1B—N2B—H2B119.4 (12)
O5A—N3A—O4A123.75 (12)O4B—N3B—O5B123.91 (11)
O5A—N3A—C8A118.62 (11)O4B—N3B—C8B118.19 (11)
O4A—N3A—C8A117.62 (11)O5B—N3B—C8B117.9 (1)
N1A—C1A—C2A114.26 (11)N1B—C1B—C2B114.10 (11)
N1A—C1A—O1A119.11 (11)N1B—C1B—O1B119.27 (10)
C2A—C1A—O1A126.58 (11)C2B—C1B—O1B126.55 (11)
C3A—C2A—C1A103.64 (11)C3B—C2B—C1B103.64 (11)
C3A—C2A—H2AA128.2C3B—C2B—H2BA128.2
C1A—C2A—H2AA128.2C1B—C2B—H2BA128.2
N2A—C3A—C2A106.11 (11)N2B—C3B—C2B106.49 (11)
N2A—C3A—C4A122.50 (12)N2B—C3B—C4B121.76 (12)
C2A—C3A—C4A131.36 (12)C2B—C3B—C4B131.75 (12)
C3A—C4A—H4AA109.5C3B—C4B—H4BA109.5
C3A—C4A—H4AB109.5C3B—C4B—H4BB109.5
H4AA—C4A—H4AB109.5H4BA—C4B—H4BB109.5
C3A—C4A—H4AC109.5C3B—C4B—H4BC109.5
H4AA—C4A—H4AC109.5H4BA—C4B—H4BC109.5
H4AB—C4A—H4AC109.5H4BB—C4B—H4BC109.5
C10A—C5A—C6A121.96 (12)C10B—C5B—C6B122.51 (11)
C10A—C5A—S1A119.15 (10)C10B—C5B—S1B118.58 (9)
C6A—C5A—S1A118.86 (10)C6B—C5B—S1B118.90 (9)
C7A—C6A—C5A119.25 (12)C7B—C6B—C5B118.43 (11)
C7A—C6A—H6A120.4C7B—C6B—H6B120.8
C5A—C6A—H6A120.4C5B—C6B—H6B120.8
C6A—C7A—C8A118.10 (12)C6B—C7B—C8B118.56 (11)
C6A—C7A—H7A121.0C6B—C7B—H7B120.7
C8A—C7A—H7A121.0C8B—C7B—H7B120.7
C9A—C8A—C7A123.37 (12)C9B—C8B—C7B123.43 (11)
C9A—C8A—N3A118.64 (12)C9B—C8B—N3B118.23 (11)
C7A—C8A—N3A117.99 (12)C7B—C8B—N3B118.33 (11)
C8A—C9A—C10A118.33 (12)C8B—C9B—C10B118.07 (11)
C8A—C9A—H9A120.8C8B—C9B—H9B121.0
C10A—C9A—H9A120.8C10B—C9B—H9B121.0
C5A—C10A—C9A118.99 (12)C9B—C10B—C5B118.99 (11)
C5A—C10A—H10A120.5C9B—C10B—H10B120.5
C9A—C10A—H10A120.5C5B—C10B—H10B120.5
O2A—S1A—O1A—C1A50.95 (10)O2B—S1B—O1B—C1B163.12 (8)
O3A—S1A—O1A—C1A178.82 (9)O3B—S1B—O1B—C1B32.2 (1)
C5A—S1A—O1A—C1A64.92 (9)C5B—S1B—O1B—C1B83.75 (9)
C1A—N1A—N2A—C3A0.16 (13)C1B—N1B—N2B—C3B0.10 (13)
N2A—N1A—C1A—C2A0.21 (14)N2B—N1B—C1B—C2B0.34 (14)
N2A—N1A—C1A—O1A177.66 (10)N2B—N1B—C1B—O1B177.21 (10)
S1A—O1A—C1A—N1A88.97 (12)S1B—O1B—C1B—N1B83.78 (12)
S1A—O1A—C1A—C2A93.93 (13)S1B—O1B—C1B—C2B99.77 (13)
N1A—C1A—C2A—C3A0.48 (15)N1B—C1B—C2B—C3B0.64 (14)
O1A—C1A—C2A—C3A177.70 (11)O1B—C1B—C2B—C3B177.24 (11)
N1A—N2A—C3A—C2A0.46 (14)N1B—N2B—C3B—C2B0.50 (14)
N1A—N2A—C3A—C4A177.73 (11)N1B—N2B—C3B—C4B179.33 (12)
C1A—C2A—C3A—N2A0.53 (13)C1B—C2B—C3B—N2B0.64 (13)
C1A—C2A—C3A—C4A177.43 (13)C1B—C2B—C3B—C4B179.16 (14)
O2A—S1A—C5A—C10A17.63 (12)O2B—S1B—C5B—C10B25.67 (11)
O3A—S1A—C5A—C10A152.3 (1)O3B—S1B—C5B—C10B160.25 (9)
O1A—S1A—C5A—C10A98.95 (10)O1B—S1B—C5B—C10B83.51 (10)
O2A—S1A—C5A—C6A164.5 (1)O2B—S1B—C5B—C6B155.4 (1)
O3A—S1A—C5A—C6A29.83 (12)O3B—S1B—C5B—C6B20.82 (11)
O1A—S1A—C5A—C6A78.91 (10)O1B—S1B—C5B—C6B95.42 (10)
C10A—C5A—C6A—C7A0.67 (19)C10B—C5B—C6B—C7B0.14 (18)
S1A—C5A—C6A—C7A178.47 (10)S1B—C5B—C6B—C7B178.75 (9)
C5A—C6A—C7A—C8A1.16 (19)C5B—C6B—C7B—C8B0.55 (18)
C6A—C7A—C8A—C9A1.0 (2)C6B—C7B—C8B—C9B0.98 (19)
C6A—C7A—C8A—N3A178.18 (11)C6B—C7B—C8B—N3B178.28 (11)
O5A—N3A—C8A—C9A178.73 (12)O4B—N3B—C8B—C9B7.47 (17)
O4A—N3A—C8A—C9A0.58 (17)O5B—N3B—C8B—C9B173.24 (11)
O5A—N3A—C8A—C7A0.50 (17)O4B—N3B—C8B—C7B173.24 (11)
O4A—N3A—C8A—C7A179.80 (12)O5B—N3B—C8B—C7B6.06 (17)
C7A—C8A—C9A—C10A0.3 (2)C7B—C8B—C9B—C10B0.67 (19)
N3A—C8A—C9A—C10A178.90 (11)N3B—C8B—C9B—C10B178.59 (11)
C6A—C5A—C10A—C9A0.06 (19)C8B—C9B—C10B—C5B0.05 (18)
S1A—C5A—C10A—C9A177.74 (10)C6B—C5B—C10B—C9B0.45 (18)
C8A—C9A—C10A—C5A0.25 (19)S1B—C5B—C10B—C9B178.44 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2A—H2A···N1B0.875 (17)2.047 (17)2.9063 (15)167.0 (15)
N2B—H2B···O4Ai0.853 (19)2.121 (19)2.9630 (15)169.1 (16)
C2B—H2BA···O2Bii0.952.633.3452 (15)132
C2B—H2BA···O4Biii0.952.663.5201 (15)151
C4B—H4BC···O5Biii0.982.603.5814 (17)177
C6B—H6B···O3Biv0.952.483.3910 (15)160
C7B—H7B···O2Bv0.952.393.1622 (15)138
C10B—H10B···O5Bvi0.952.543.3418 (16)142
Symmetry codes: (i) x, y+1, z+1; (ii) x+2, y, z+2; (iii) x+1, y1, z; (iv) x+1, y, z+2; (v) x1, y, z; (vi) x+1, y, z.
Conformation-dependant angles and distances (Å, °) in I top
Torsion angleMolecule AMolecule B
N1—C1—O1—S188.97 (12)83.78 (12)
C1—O1—S1—C564.92 (9)-83.75 (9)
O1—S1—C5—C678.91 (10)95.42 (10)
C7—C8—N3—O5-0.50 (17)-6.06 (17)
Dihedral anglea
bz/nitro1.37 (10)6.78 (4)
bz/pz43.10 (4)37.22 (5)
Centroid···centroida
Cg(bz)···Cg(pz)4.505 (1)b4.936 (1)b
Notes: (a) Abbreviations: bz = benzene; pz = pyrazole; Cg = centroid. (b) These distances do not imply any overlap, they merely show that the rings in A are closer than those in B.
Hydrogen bonds and other close contacts (Å, °) in I top
Hydrogen bonds
D—H···AD—HH···AD···AD—H···A
N2A—H2A···N1B0.875 (17)2.047 (17)2.9063 (15)167.0 (15)
N2B—H2B···O4Ai0.853 (19)2.121 (19)2.9630 (15)169.1 (16)
C2B—H2BA···O2Bii0.952.633.3452 (15)132.1
C2B—H2BA···O4Biii0.952.663.5201 (15)151.4
C4B—H4BC···O5Biii0.982.603.5814 (17)176.8
C6B—H6B···O3Biv0.952.483.3910 (15)160.1
C7B—H7B···O2Bv0.952.393.1622 (15)137.6
C10B—H10B···O5Bv0.952.543.3418 (16)142.0
ππ stacks
Ring 1···ring 2DistanceDihedral
Cg(pzA)···Cg(bzB)3.524 (1)5.41 (4)
Abbreviations: Cg = centroid; bz = benzene; pz = pyrazole. Symmetry codes: (i) = -x, -y + 1, -z + 1; (ii) = -x + 2, -y, -z + 2; (iii) = x + 1, y - 1, z; (iv) = -x + 1, -y, -z + 2; (v) = x - 1, y, z; (vi) x + 1, y, z.
 

Acknowledgements

One of the authors (V) is grateful to the DST–PURSE Project, Vijnana Bhavana, UOM for providing research facilities. HSY thanks UGC for a BSR Faculty fellowship for three years.

References

First citationAnsari, A., Ali, A., Asif, M. & Shamsuzzaman, S. (2017). New J. Chem. 41, 16–41.  Web of Science CrossRef CAS Google Scholar
First citationArchana, S. D., Nagma Banu, H. A., Kalluraya, B., Yathirajan, H. S., Balerao, R. & Butcher, R. J. (2022). IUCrData, 7, x220924.  Google Scholar
First citationAsma, Kalluraya, B., Yathirajan, H. S., Rathore, R. S. & Glidewell, C. (2018). Acta Cryst. E74, 1783–1789.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationBaddeley, T. C., Wardell, S. M. S. V., Tiekink, E. R. T. & Wardell, J. L. (2012). Acta Cryst. E68, o1016–o1017.  CSD CrossRef IUCr Journals Google Scholar
First citationBruker (2023). APEX5. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationDwivedi, J., Sharma, S., Jain, S. & Singh, A. (2018). Mini Rev. Med. Chem. 18, 918–947.  CrossRef CAS PubMed Google Scholar
First citationEbenezer, O., Shapi, M. & Tuszynski, J. A. (2022). Biomedicines 10, 1124.  Web of Science CrossRef PubMed Google Scholar
First citationFaria, J. V., Vegi, P. F., Miguita, A. G. C., dos Santos, M. S., Boechat, N. & Bernardino, A. M. R. (2017). Bioorg. Med. Chem. 25, 5891–5903.  CrossRef CAS PubMed Google Scholar
First citationFustero, S., Sánchez-Roselló, M., Barrio, P. & Simón-Fuentes, A. (2011). Chem. Rev. 111, 6984–7034.  Web of Science CrossRef CAS PubMed Google Scholar
First citationFustero, S., Simón-Fuentes, A. & Sanz-Cervera, J. F. (2009). Org. Prep. Proced. Int. 41, 253–290.  Web of Science CrossRef CAS Google Scholar
First citationGarcía-Lozano, J., Server-Carrió, J., Escrivà, E., Folgado, J.-V., Molla, C. & Lezama, L. (1997). Polyhedron, 16, 939–944.  Google Scholar
First citationGroom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179.  Web of Science CrossRef IUCr Journals Google Scholar
First citationKarrouchi, K., Radi, S., Ramli, Y., Taoufik, J., Mabkhot, Y. N., Al-aizari, F. A. & Ansar, M. (2018). Molecules, 23, 134.  CrossRef PubMed Google Scholar
First citationKim, Y., Kim, H., Lee, J., Lee, J. K., Min, S. J., Seong, J., Rhim, H., Tae, J., Lee, H. J. & Choo, H. (2018). J. Med. Chem. 61, 7218–7233.  CrossRef CAS PubMed Google Scholar
First citationKrause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3–10.  Web of Science CSD CrossRef ICSD CAS IUCr Journals Google Scholar
First citationMetwally, N. H., Elgemeie, G. H. & Jones, P. G. (2021). Acta Cryst. E77, 1054–1057.  CrossRef IUCr Journals Google Scholar
First citationMurtaza, S., Kausar, N., Tahir, M. N., Tariq, J. & Bibi, S. (2012). Acta Cryst. E68, o2196.  CrossRef IUCr Journals Google Scholar
First citationNaim, M. J., Alam, O., Nawaz, F., Alam, M. J. & Alam, P. (2016). J. Pharm. Bioallied Sci. 8, 2–17.  CAS PubMed Google Scholar
First citationPatil, S. B. (2020). J. Pharm. Sci. Res. 12, 402–404.  Google Scholar
First citationPintro, C. J., Long, A. K., Amonette, A. J., Lobue, J. M. & Padgett, C. W. (2022). Acta Cryst. E78, 336–339.  CrossRef IUCr Journals Google Scholar
First citationPriyanka, P., Jayanna, B. K., Sunil Kumar, Y. C., Shreenivas, M. T., Srinivasa, G. R., Divakara, T. R., Yathirajan, H. S. & Parkin, S. (2022). Acta Cryst. E78, 1084–1088.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSheldrick, G. M. (2015a). Acta Cryst. A71, 3–8.  Web of Science CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (2015b). Acta Cryst. C71, 3–8.  Web of Science CrossRef IUCr Journals Google Scholar
First citationSpackman, P. R., Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Jayatilaka, D. & Spackman, M. A. (2021). J. Appl. Cryst. 54, 1006–1011.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSteinbach, G., Lynch, P. M., Phillips, R. K. S., Wallace, M. H., Hawk, E., Gordon, G. B., Wakabayashi, N., Saunders, B., Shen, Y., Fujimura, T., Su, L.-K., Levin, B., Godio, L., Patterson, S., Rodriguez-Bigas, M. A., Jester, S. L., King, K. L., Schumacher, M., Abbruzzese, J., DuBois, R. N., Hittelman, W. N., Zimmerman, S., Sherman, J. W. & Kelloff, G. (2000). N. Engl. J. Med. 342, 1946–1952.  Web of Science CrossRef PubMed CAS Google Scholar
First citationWardell, S. M. S. V., Tiekink, E. R. T. & Wardell, J. L. (2012). Acta Cryst. E68, o1086–o1087.  CrossRef IUCr Journals Google Scholar
First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationYet, L. (2018). Methods and Principles in Medicinal Chemistry. London, Hoboken, NJ: John Wiley & Sons.  Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds