Two thio­semicarbazones derived from salicylaldehyde: very specific hydrogen-bonding inter­actions of the N—H...S=C type

The mol­ecular structures of two salicylaldehyde thio­semi­carba­zone derivatives, namely sali­cylaldehyde 4-phenyl­thio­semicarbazone, C₁₄H₁₃N₃OS, (I), and 4-methoxysali­cyl­­aldehyde 4-phenyl­thio­semicarbazone, C₁₅H₁₅N₃O₂S, (II), both of potential pharmacological inter­est, are found in the keto (thione) tautomeric form. The first compound represents a second triclinic polymorph of composition β-C₁₄H₁₃N₃OS. Although both polymorphs crystallize in the same space group (P), the α-polymorph [Seena, Kurup & Suresh (2008). J. Chem. Crystallogr. 38, 93–96] differs from the β form in its unit-cell volume at 293 K. The mol­ecules in the crystal structures of (I) and (II) are linked into centrosymmetric R²₂(8) dimers by hydrogen bonds of the N—H...S=C type. These dimers are connected through π–π stacking and T-shaped C—H...π inter­actions into three-dimensional net­works.

S1. Comment

Thiosemicarbazones are a class of organic molecules which belong to a large family of thiourea derivatives (Casas et al., 2000). Widespread interest in the chemistry of thiosemicarbazones is associated with their broad spectrum of biological activities with potential uses in antibacterial, antiviral and antitumour treatments (Bharti et al., 2002; Smee & Sidwell, 2003; Hu et al., 2006; Oliveira et al., 2007). Many of their properties are a function of the parent aldehyde or ketone, and these properties can therefore be elegantly tuned by the appropriate choice of parent. From a structural perspective, thiosemicarbazones attract attention as interesting ligands due to their tendency to undergo tautomerism and form planar highly rigid Schiff bases capable of imposing a variety of mixed-donor coordination environments about metal cations. Thiosemicarbazones derived from salicylaldehyde can exist in several tautomeric forms but the most interesting are those denoted A and B in scheme 1. Such molecular isomerization can result in different binding modes. In form A, the molecule can act as a monoanionic ligand after losing the H atom from the hydroxyl group, or as a dianionic ligand after losing H atoms from the mercapto and hydroxyl groups of form B.

We present here the crystal structures of two closely related thiosemicarbazones derived from salicylaldehyde: salicylaldehyde 4-phenylthiosemicarbazone, (I), and 4-methoxysalicylaldehyde 4-phenylthiosemicarbazone, (II). The structure of (I) has been reported previously (Seena et al., 2008). The compound crystallized in the same space group (P1) and we refer to it as the α-polymorph (obtained from ethanol). We have now obtained a second triclinic polymorph of (I), denoted the β-polymorph (obtained from methanol). Although both polymorphs crystallize in space group No. 2, they have different unit-cell volumes at 293 K and their unit-cell parameters are different [in particular, V = 2002.1 (5) ų for the α-polymorph and V = 1339.6 (1) ų for the β-polymorph]. These two forms of (I) have different numbers of molecules in the asymmetric unit (three and two, respectively). The asymmetric unit of (I) consists of two crystallographically independent molecules, (Ia) and (Ib) (Fig. 1). The molecular structures of (I) (in both polymorphs) and (II) (Fig. 2) are very similiar, but not equal. The crystal structures are characterized by a great variety of interactions, especially of the N—H···S type, and these will be discussed later.

The atom-labelling schemes are almost the same. In the following discussion, the order of the compounds for a given value is (Ia) and (Ib) of (I), then (II). Selected bond lengths and bond angles for (I) and (II) are given in Tables 1 and 3. Similar to many uncomplexed and unprotonated thiosemicarbazones (Soriano-García et al., 1986; Dinçer et al., 2005; Seena et al., 2008), a trans configuration of atom S1 with respect to atom N3 is observed [S1—C1—N2—N3 = -178.51 (10), -178.04 (10) and 176.30 (9)°] and atom N1 is in a cis configuration with respect to atom N3. The C1—S1 bond distance of 1.6758 (14) Å [1.6827 (13) and 1.6768 (13) Å] does not differ significantly from that found in thiourea (Truter, 1967). This bond, together with the C1—N2 bond of 1.3515 (17) Å [1.3416 (17) and 1.3441 (17) Å] and the C1—N1 bond of 1.3341 (17) Å [1.3361 (17) and 1.3331 (18) Å], indicate that the molecules in the crystal structures of (I) and (II) are in the keto (thione) form. This is also in agreement with the absence of a strong band in the IR spectra centred at 2500 cm^-1 [ν(S—H) stretching mode].

The molecular structures of (I) and (II) consist of three structural fragments: salicyl and phenyl parts separated by the central thiosemicarbazone part. The salicyl–thiosemicarbazone parts of molecules are almost planar. Maximum deviations from the plane in molecule (Ia) are -0.214 (1), 0.183 (1) and -0.138 (2) Å for N11, O1 and C17, respectively [-0.192 (1), 0.107 (1) and 0.097 (1) Å for N21, N22 and O2 in (Ib) and 0.285 (2), -0.140 (2), -0.092 (1) Å for N1, C15 and C1 in (II)]. The dihedral angle between the planes of the salicyl–thiosemicarbazone parts and the phenyl ring on the N1 substituents of 64.44 (4)° [and 53.07 (4)° and 52.16 (5)°] indicates non-planarity of the ligands, although the thiosemicarbazone parts themselves are planar. Such an arrangement allows delocalization of the π-electrons in the N1—C1—N2—N3—C2 moieties. The salicylaldimine parts of the molecules in the crystal structures of (I) and (II) are characterized by a six-membered pseudoaromatic rings(N3—C2—C3—C4—O1—H1O). Rings are formed by an intramolecular hydrogen bond [S(6)] which is enhanced by π-electron delocalization as can be seen easily from the bond lengths within the rings (Tables 1 and 3). Such resonance-assisted hydrogen bonds seem to be the general features of the crystal structures of thiosemicarbazones and Schiff bases derived from salicylaldehyde (Soriano-García et al., 1986; Popović et al., 2002). The C4—O1 bond lengths are comparable with those found in phenols: 1.3563 (17), 1.3575 (16) and 1.3551 (17) Å (Allen et al., 1987). In contrast, C2—N3 [1.2816 (17), 1.2790 (17), 1.2797 (17) Å] is assigned as a double bond. The endocyclic bond distances and angles found in the phenyl rings, with the exception of that at C3, do not differ from those in normal sp² hybridized moieties. The measured collapse of the C4—C3—C8 angles together with good electron donor properties of the O atom may be a consequence of the conjugation of the phenyl ring with the thiosemicarbazone parts of the molecules.

The crystal packings are characterized by a great variety of hydrogen bonds (presented in Tables 2 and 4). A close inspection of the unit cells (Figs. 3 and 4) and two-dimensional fingerprint plots derived from Hirshfeld surfaces (McKinnon et al., 2004) of both polymorphs of (I) and (II) revealed very specific N—H···S hydrogen bonding (spikes centred around 2.6 Å). This type of structural motif [denoted R²₂(8); Etter et al., 1990] is very common in the crystal structures of thiosemicarbazones (Soriano-García et al., 1986; Sampath et al., 2003; Dinçer et al., 2005).

Figs. 5(a) and 5(b) unambiguously show that different intermolecular interactions are present in the polymorphs α and β, which results in different packing modes. In polymorph α, the shortest contacts corespond to the very close H···H contacts [H25···H25ⁱ and H3···H27ⁱⁱ are 2.25 (4) and 2.25 (6) Å; symmetry codes: (i) -x, -y, 2 - z ; (ii) 1 - x, -y, 1 - z]. In plots of (I) and (II) (Figs. 5b and 5c) `wings' are more pronounced, which resemble [indicate?] aromatic interactions [π···π stacking, C14···C214 and C114···C24 distances are 3.237 (2) and 3.267 (2) Å in (I)] and there are T-shaped C—H···π contacts between the molecules in (II) [C12···H5ⁱⁱⁱ and C10···H15B^iv = 2.93 and 2.86 Å; symmetry codes: (iii) 2 - x, -y, -z ; (iv) -2 + x, 1 + y, z)].

Related literature

For related literature, see: Allen et al. (1987); Bharti et al. (2002); Casas et al. (2000); Dinçer et al. (2005); Etter et al. (1990); Hu et al. (2006); McKinnon et al. (2004); Oliveira et al. (2007); Popović et al. (2002); Purohit et al. (1989); Sampath et al. (2003); Seena et al. (2008); Smee & Sidwell (2003); Soriano-García, Valdés-Martínez, Toscano, Gómez-Lara & Villalobos-Peñaloza (1986); Truter (1967).

S2. Experimental

Compound (I) was prepared by slight modification of the procedure described by Purohit et al. (1989), using methanol as the solvent instead of ethanol. White needle-like crystals were obtained directly from the reaction mixture as the first form of compound (I). The structure of this α-polymorph, obtained from ethanol, was recently published by Seena et al. (2008). The remaining mother liquor was kept at room temperature and after 2–3 weeks yielded the β-polymorph of compound (I), in the form of transparent plates [prismatic in CIF tables - please clarify]. The crystals were filtered off and dried over KOH. From this batch were picked single crystals suitable for X-ray diffraction.

Compound (II) was prepared by adopting a similar procedure as for (I). Equimolar amounts of 4-phenylthiosemicarbazide and 4-methoxysalicylaldehyde were dissolved in methanol and stirred until white needle-like crystals started to precipitate (4–5 h). After standing overnight, the compound was filtered off and dried over KOH [identification of this product?]. The mother liquor was kept at room temperature and after 6 d yielded single crystals of (II) suitable for X-ray diffraction. Elemental analysis, calculated for C₁₅H₁₅N₃O₂S: C 59.78, H 5.02, N 13.94, S 10.64%; found: C 59.67, H 4.96, N 13.87, S 10.60%.

S3. Refinement

H atoms were constrained to ideal geometry using an appropriate riding model, with C—H = 0.93–0.96 Å, N—H = 0.86 Å and O—H = 0.82 Å, and with U_iso(H) = 1.2U_eq(C, N) or 1.5U_eq(O).

Computing details

For both compounds, data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED (Oxford Diffraction, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: PLATON (Spek, 2003).

Figures

	Fig. 1. A view of the molecular structure of the centrosymmetric dimer of (I), with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. Hydrogen bonds are indicated by dashed lines. [Symmetry code: (A) 1+x, y, z.]
	Fig. 2. A view of the molecular structure of (II), with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 3. The crystal packing of (I), viewed down (a) the b axis and (b) the c axis. Hydrogen bonds and π–π stacking interactions are indicated by dashed lines.
	Fig. 4. The crystal packing of (II), viewed down (a) the a axis and (b) the b axis. Hydrogen bonds and C—H···π interactions are indicated by dashed lines.
	Fig. 5. Two-dimensional fingerprint plots for (a) the α-polymorph of (I), (b) the β-polymorph of (I) and (c) (II).

(I) salicylaldehyde 4-phenylthiosemicarbazone

Crystal data

C14H13N3OS	Z = 4
Mr = 271.34	F(000) = 568
Triclinic, P1	Dx = 1.345 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 10.6328 (3) Å	Cell parameters from 13724 reflections
b = 11.1114 (3) Å	θ = 3.8–34.8°
c = 12.8839 (10) Å	µ = 0.24 mm^−1
α = 75.251 (5)°	T = 293 K
β = 65.652 (2)°	Prismatic, colourless
γ = 81.539 (2)°	0.79 × 0.59 × 0.20 mm
V = 1339.56 (12) Å^3

Data collection

Oxford Diffraction Xcalibur CCD diffractometer	4676 independent reflections
Radiation source: fine-focus sealed tube	4184 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.012
ω scans	θmax = 25.0°, θmin = 3.8°
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2003)	h = −12→12
Tmin = 0.856, Tmax = 0.936	k = −13→13
14306 measured reflections	l = −13→15

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.079	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.038P)^2 + 0.3482P] where P = (Fo^2 + 2Fc^2)/3
4676 reflections	(Δ/σ)max = 0.001
345 parameters	Δρmax = 0.15 e Å^−3
0 restraints	Δρmin = −0.20 e Å^−3

Special details

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C11	0.57661 (13)	0.79953 (12)	0.39556 (11)	0.0371 (3)
C12	0.38367 (14)	0.79827 (13)	0.69151 (12)	0.0396 (3)
H12	0.4426	0.8482	0.6971	0.048*
C13	0.26358 (14)	0.75380 (13)	0.79479 (11)	0.0390 (3)
C14	0.15581 (15)	0.69642 (14)	0.79333 (12)	0.0448 (3)
C15	0.04261 (17)	0.65928 (16)	0.89493 (14)	0.0541 (4)
H15	−0.0289	0.6219	0.8929	0.065*
C16	0.03510 (18)	0.67723 (16)	0.99887 (14)	0.0579 (4)
H16	−0.0416	0.6522	1.0670	0.070*
C17	0.14072 (19)	0.73219 (17)	1.00292 (13)	0.0597 (4)
H17	0.1360	0.7432	1.0736	0.072*
C18	0.25273 (17)	0.77046 (15)	0.90198 (13)	0.0501 (4)
H18	0.3231	0.8084	0.9050	0.060*
C19	0.52114 (14)	0.70249 (13)	0.26887 (12)	0.0412 (3)
C110	0.62569 (16)	0.61911 (16)	0.22067 (14)	0.0546 (4)
H110	0.6883	0.5852	0.2550	0.066*
C111	0.6362 (2)	0.58653 (17)	0.12048 (16)	0.0662 (5)
H111	0.7069	0.5311	0.0867	0.079*
C112	0.5424 (2)	0.63580 (19)	0.07068 (15)	0.0674 (5)
H112	0.5487	0.6123	0.0043	0.081*
C113	0.43998 (19)	0.71922 (18)	0.11876 (14)	0.0628 (5)
H113	0.3772	0.7528	0.0845	0.075*
C114	0.42906 (16)	0.75399 (15)	0.21795 (13)	0.0487 (4)
H114	0.3601	0.8116	0.2499	0.058*
N11	0.49815 (12)	0.72982 (12)	0.37811 (10)	0.0443 (3)
H11N	0.4276	0.6986	0.4378	0.053*
N12	0.53128 (11)	0.82126 (11)	0.50405 (10)	0.0406 (3)
H12N	0.5781	0.8673	0.5182	0.049*
N13	0.41248 (11)	0.77191 (11)	0.59270 (9)	0.0386 (3)
O1	0.15616 (12)	0.67825 (14)	0.69303 (10)	0.0675 (4)
H1O	0.2316	0.6950	0.6400	0.101*
S1	0.72434 (4)	0.86032 (4)	0.29361 (3)	0.04948 (12)
C21	−0.15678 (13)	0.89188 (12)	0.56879 (11)	0.0363 (3)
C22	0.00350 (13)	0.67580 (12)	0.39304 (11)	0.0368 (3)
H22	−0.0584	0.6939	0.3565	0.044*
C23	0.10949 (13)	0.57819 (12)	0.36235 (11)	0.0342 (3)
C24	0.21183 (13)	0.54659 (12)	0.40808 (11)	0.0370 (3)
C25	0.31164 (14)	0.45392 (13)	0.37349 (13)	0.0460 (3)
H25	0.3789	0.4328	0.4045	0.055*
C26	0.31156 (16)	0.39288 (14)	0.29318 (14)	0.0509 (4)
H26	0.3801	0.3317	0.2691	0.061*
C27	0.21119 (16)	0.42124 (14)	0.24788 (13)	0.0496 (4)
H27	0.2114	0.3790	0.1941	0.059*
C28	0.11097 (15)	0.51243 (13)	0.28288 (12)	0.0420 (3)
H28	0.0426	0.5308	0.2530	0.050*
C29	−0.12202 (14)	0.91015 (12)	0.74222 (11)	0.0371 (3)
C210	−0.25224 (16)	0.89519 (15)	0.82987 (14)	0.0511 (4)
H210	−0.3211	0.8638	0.8188	0.061*
C211	−0.27949 (18)	0.92724 (16)	0.93415 (14)	0.0595 (4)
H211	−0.3673	0.9178	0.9934	0.071*
C212	−0.1778 (2)	0.97295 (16)	0.95089 (14)	0.0603 (4)
H212	−0.1965	0.9936	1.0215	0.072*
C213	−0.04887 (19)	0.98809 (16)	0.86358 (14)	0.0576 (4)
H213	0.0196	1.0199	0.8748	0.069*
C214	−0.01993 (16)	0.95638 (13)	0.75878 (13)	0.0446 (3)
H214	0.0679	0.9662	0.6998	0.054*
N21	−0.08594 (12)	0.86846 (11)	0.63721 (10)	0.0408 (3)
H21N	−0.0105	0.8234	0.6156	0.049*
N22	−0.11577 (11)	0.82821 (10)	0.48379 (10)	0.0389 (3)
H22N	−0.1579	0.8442	0.4370	0.047*
N23	−0.00950 (11)	0.73849 (10)	0.46782 (9)	0.0351 (2)
O2	0.21752 (10)	0.60625 (11)	0.48570 (9)	0.0519 (3)
H2O	0.1509	0.6558	0.5029	0.078*
S2	−0.29168 (4)	0.99553 (4)	0.58034 (4)	0.05216 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C11	0.0352 (7)	0.0416 (7)	0.0377 (7)	0.0042 (5)	−0.0193 (6)	−0.0084 (6)
C12	0.0394 (7)	0.0455 (7)	0.0396 (7)	0.0028 (6)	−0.0211 (6)	−0.0118 (6)
C13	0.0423 (7)	0.0418 (7)	0.0363 (7)	0.0027 (6)	−0.0190 (6)	−0.0109 (6)
C14	0.0456 (8)	0.0543 (8)	0.0408 (8)	0.0003 (6)	−0.0205 (6)	−0.0165 (6)
C15	0.0502 (9)	0.0627 (10)	0.0512 (9)	−0.0130 (7)	−0.0178 (7)	−0.0128 (7)
C16	0.0625 (10)	0.0623 (10)	0.0401 (8)	−0.0157 (8)	−0.0114 (7)	−0.0036 (7)
C17	0.0745 (11)	0.0728 (11)	0.0341 (8)	−0.0144 (9)	−0.0196 (8)	−0.0119 (7)
C18	0.0578 (9)	0.0592 (9)	0.0406 (8)	−0.0110 (7)	−0.0228 (7)	−0.0124 (7)
C19	0.0390 (7)	0.0468 (8)	0.0372 (7)	−0.0094 (6)	−0.0097 (6)	−0.0129 (6)
C110	0.0465 (9)	0.0595 (10)	0.0556 (9)	0.0001 (7)	−0.0144 (7)	−0.0195 (8)
C111	0.0679 (11)	0.0625 (11)	0.0577 (10)	−0.0073 (9)	−0.0030 (9)	−0.0301 (9)
C112	0.0834 (13)	0.0781 (12)	0.0431 (9)	−0.0297 (11)	−0.0133 (9)	−0.0223 (9)
C113	0.0672 (11)	0.0811 (12)	0.0471 (9)	−0.0179 (9)	−0.0267 (8)	−0.0098 (9)
C114	0.0471 (8)	0.0547 (9)	0.0451 (8)	−0.0045 (7)	−0.0175 (7)	−0.0118 (7)
N11	0.0367 (6)	0.0599 (8)	0.0368 (6)	−0.0097 (5)	−0.0094 (5)	−0.0159 (5)
N12	0.0352 (6)	0.0530 (7)	0.0374 (6)	−0.0032 (5)	−0.0160 (5)	−0.0125 (5)
N13	0.0345 (6)	0.0473 (6)	0.0354 (6)	0.0035 (5)	−0.0160 (5)	−0.0103 (5)
O1	0.0509 (7)	0.1168 (11)	0.0488 (6)	−0.0156 (7)	−0.0181 (5)	−0.0371 (7)
S1	0.0430 (2)	0.0681 (3)	0.0388 (2)	−0.01540 (17)	−0.01489 (16)	−0.00862 (17)
C21	0.0359 (7)	0.0354 (7)	0.0393 (7)	−0.0017 (5)	−0.0146 (6)	−0.0110 (6)
C22	0.0367 (7)	0.0406 (7)	0.0353 (7)	0.0003 (5)	−0.0161 (6)	−0.0098 (6)
C23	0.0336 (7)	0.0355 (7)	0.0306 (6)	−0.0030 (5)	−0.0094 (5)	−0.0071 (5)
C24	0.0341 (7)	0.0416 (7)	0.0345 (7)	−0.0051 (5)	−0.0107 (5)	−0.0097 (5)
C25	0.0369 (7)	0.0462 (8)	0.0543 (9)	0.0028 (6)	−0.0192 (7)	−0.0103 (7)
C26	0.0451 (8)	0.0424 (8)	0.0606 (10)	0.0066 (6)	−0.0140 (7)	−0.0198 (7)
C27	0.0550 (9)	0.0468 (8)	0.0494 (8)	0.0019 (7)	−0.0166 (7)	−0.0235 (7)
C28	0.0453 (8)	0.0451 (8)	0.0399 (7)	−0.0010 (6)	−0.0189 (6)	−0.0131 (6)
C29	0.0416 (7)	0.0354 (7)	0.0367 (7)	0.0003 (5)	−0.0170 (6)	−0.0100 (5)
C210	0.0453 (8)	0.0578 (9)	0.0524 (9)	−0.0088 (7)	−0.0131 (7)	−0.0227 (7)
C211	0.0588 (10)	0.0633 (10)	0.0464 (9)	−0.0089 (8)	−0.0037 (8)	−0.0205 (8)
C212	0.0838 (12)	0.0606 (10)	0.0424 (8)	−0.0094 (9)	−0.0242 (9)	−0.0183 (7)
C213	0.0693 (11)	0.0644 (10)	0.0520 (9)	−0.0166 (8)	−0.0310 (9)	−0.0144 (8)
C214	0.0475 (8)	0.0465 (8)	0.0411 (8)	−0.0095 (6)	−0.0188 (6)	−0.0050 (6)
N21	0.0361 (6)	0.0501 (7)	0.0426 (6)	0.0081 (5)	−0.0187 (5)	−0.0209 (5)
N22	0.0399 (6)	0.0418 (6)	0.0402 (6)	0.0079 (5)	−0.0207 (5)	−0.0147 (5)
N23	0.0331 (6)	0.0366 (6)	0.0342 (6)	0.0010 (4)	−0.0115 (5)	−0.0098 (5)
O2	0.0424 (6)	0.0719 (7)	0.0555 (6)	0.0082 (5)	−0.0258 (5)	−0.0326 (6)
S2	0.0526 (2)	0.0511 (2)	0.0677 (3)	0.01951 (17)	−0.0352 (2)	−0.03039 (19)

Geometric parameters (Å, º)

C11—N11	1.3341 (17)	C21—N21	1.3361 (17)
C11—N12	1.3515 (17)	C21—N22	1.3416 (17)
C11—S1	1.6758 (14)	C21—S2	1.6827 (13)
C12—N13	1.2816 (17)	C22—N23	1.2790 (17)
C12—C13	1.447 (2)	C22—C23	1.4470 (18)
C12—H12	0.9300	C22—H22	0.9300
C13—C18	1.3955 (19)	C23—C28	1.3953 (18)
C13—C14	1.400 (2)	C23—C24	1.4019 (18)
C14—O1	1.3563 (17)	C24—O2	1.3575 (16)
C14—C15	1.380 (2)	C24—C25	1.3810 (19)
C15—C16	1.372 (2)	C25—C26	1.374 (2)
C15—H15	0.9300	C25—H25	0.9300
C16—C17	1.380 (2)	C26—C27	1.378 (2)
C16—H16	0.9300	C26—H26	0.9300
C17—C18	1.371 (2)	C27—C28	1.373 (2)
C17—H17	0.9300	C27—H27	0.9300
C18—H18	0.9300	C28—H28	0.9300
C19—C114	1.375 (2)	C29—C214	1.3779 (19)
C19—C110	1.379 (2)	C29—C210	1.379 (2)
C19—N11	1.4300 (17)	C29—N21	1.4251 (17)
C110—C111	1.385 (2)	C210—C211	1.381 (2)
C110—H110	0.9300	C210—H210	0.9300
C111—C112	1.376 (3)	C211—C212	1.372 (2)
C111—H111	0.9300	C211—H211	0.9300
C112—C113	1.367 (3)	C212—C213	1.369 (2)
C112—H112	0.9300	C212—H212	0.9300
C113—C114	1.383 (2)	C213—C214	1.382 (2)
C113—H113	0.9300	C213—H213	0.9300
C114—H114	0.9300	C214—H214	0.9300
N11—H11N	0.8600	N21—H21N	0.8600
N12—N13	1.3770 (16)	N22—N23	1.3764 (15)
N12—H12N	0.8600	N22—H22N	0.8600
O1—H1O	0.8200	O2—H2O	0.8200
N11—C11—N12	116.32 (12)	N21—C21—N22	117.08 (12)
N11—C11—S1	124.73 (10)	N21—C21—S2	125.10 (10)
N12—C11—S1	118.95 (10)	N22—C21—S2	117.82 (10)
N13—C12—C13	122.93 (13)	N23—C22—C23	123.47 (12)
N13—C12—H12	118.5	N23—C22—H22	118.3
C13—C12—H12	118.5	C23—C22—H22	118.3
C18—C13—C14	117.73 (13)	C28—C23—C24	118.09 (12)
C18—C13—C12	118.56 (13)	C28—C23—C22	118.70 (12)
C14—C13—C12	123.70 (12)	C24—C23—C22	123.22 (12)
O1—C14—C15	117.54 (13)	O2—C24—C25	118.02 (12)
O1—C14—C13	121.92 (13)	O2—C24—C23	121.65 (12)
C15—C14—C13	120.51 (13)	C25—C24—C23	120.32 (12)
C16—C15—C14	120.26 (15)	C26—C25—C24	119.99 (13)
C16—C15—H15	119.9	C26—C25—H25	120.0
C14—C15—H15	119.9	C24—C25—H25	120.0
C15—C16—C17	120.37 (15)	C25—C26—C27	120.82 (14)
C15—C16—H16	119.8	C25—C26—H26	119.6
C17—C16—H16	119.8	C27—C26—H26	119.6
C18—C17—C16	119.56 (14)	C28—C27—C26	119.39 (14)
C18—C17—H17	120.2	C28—C27—H27	120.3
C16—C17—H17	120.2	C26—C27—H27	120.3
C17—C18—C13	121.54 (14)	C27—C28—C23	121.38 (13)
C17—C18—H18	119.2	C27—C28—H28	119.3
C13—C18—H18	119.2	C23—C28—H28	119.3
C114—C19—C110	120.78 (14)	C214—C29—C210	120.21 (13)
C114—C19—N11	117.98 (13)	C214—C29—N21	118.24 (12)
C110—C19—N11	121.04 (13)	C210—C29—N21	121.32 (12)
C19—C110—C111	119.08 (16)	C29—C210—C211	119.46 (14)
C19—C110—H110	120.5	C29—C210—H210	120.3
C111—C110—H110	120.5	C211—C210—H210	120.3
C112—C111—C110	120.31 (17)	C212—C211—C210	120.38 (15)
C112—C111—H111	119.8	C212—C211—H211	119.8
C110—C111—H111	119.8	C210—C211—H211	119.8
C113—C112—C111	120.00 (16)	C213—C212—C211	119.98 (15)
C113—C112—H112	120.0	C213—C212—H212	120.0
C111—C112—H112	120.0	C211—C212—H212	120.0
C112—C113—C114	120.44 (17)	C212—C213—C214	120.34 (15)
C112—C113—H113	119.8	C212—C213—H213	119.8
C114—C113—H113	119.8	C214—C213—H213	119.8
C19—C114—C113	119.36 (15)	C29—C214—C213	119.61 (14)
C19—C114—H114	120.3	C29—C214—H214	120.2
C113—C114—H114	120.3	C213—C214—H214	120.2
C11—N11—C19	125.71 (12)	C21—N21—C29	126.94 (11)
C11—N11—H11N	117.1	C21—N21—H21N	116.5
C19—N11—H11N	117.1	C29—N21—H21N	116.5
C11—N12—N13	122.03 (11)	C21—N22—N23	123.14 (11)
C11—N12—H12N	119.0	C21—N22—H22N	118.4
N13—N12—H12N	119.0	N23—N22—H22N	118.4
C12—N13—N12	115.18 (11)	C22—N23—N22	114.62 (11)
C14—O1—H1O	109.5	C24—O2—H2O	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H11N···O2	0.86	2.37	3.0881 (16)	141
O1—H1O···N13	0.82	2.01	2.7252 (16)	145
N21—H21N···O1	0.86	2.56	3.2806 (18)	142
O2—H2O···N23	0.82	1.98	2.6984 (14)	146
N12—H12N···S2^i	0.86	2.58	3.4391 (12)	175
N22—H22N···S1^ii	0.86	2.59	3.4398 (11)	172

Symmetry codes: (i) x+1, y, z; (ii) x−1, y, z.

(II) 4-methoxysalicylaldehyde 4-phenylthiosemicarbazone

Crystal data

C15H15N3O2S	Z = 2
Mr = 301.37	F(000) = 316
Triclinic, P1	Dx = 1.353 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 4.73851 (17) Å	Cell parameters from 6731 reflections
b = 11.3244 (4) Å	θ = 3.7–33.8°
c = 14.0775 (5) Å	µ = 0.23 mm^−1
α = 78.390 (3)°	T = 293 K
β = 89.547 (3)°	Prismatic, colourless
γ = 89.364 (3)°	0.40 × 0.35 × 0.30 mm
V = 739.90 (5) Å^3

Data collection

Oxford Diffraction Xcalibur CCD diffractometer	2230 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.015
Graphite monochromator	θmax = 25.0°, θmin = 3.8°
Detector resolution: 16.3426 pixels mm^-1	h = −5→5
ω scans	k = −13→13
8408 measured reflections	l = −16→16
2591 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.087	H-atom parameters constrained
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0475P)^2 + 0.1004P] where P = (Fo^2 + 2Fc^2)/3
2591 reflections	(Δ/σ)max < 0.001
192 parameters	Δρmax = 0.16 e Å^−3
0 restraints	Δρmin = −0.17 e Å^−3

Special details

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.5985 (3)	0.07055 (12)	0.32843 (9)	0.0415 (3)
C2	1.0970 (3)	−0.16180 (12)	0.39226 (10)	0.0426 (3)
H2	1.0946	−0.1625	0.4584	0.051*
C3	1.2862 (3)	−0.24382 (11)	0.35530 (10)	0.0391 (3)
C4	1.3019 (3)	−0.25023 (12)	0.25711 (10)	0.0437 (3)
C5	1.4833 (3)	−0.33096 (13)	0.22599 (10)	0.0504 (4)
H5	1.4925	−0.3340	0.1605	0.060*
C6	1.6512 (3)	−0.40717 (12)	0.29157 (11)	0.0454 (3)
C7	1.6416 (3)	−0.40270 (12)	0.38908 (11)	0.0463 (3)
H7	1.7551	−0.4537	0.4334	0.056*
C8	1.4602 (3)	−0.32108 (12)	0.41937 (10)	0.0445 (3)
H8	1.4541	−0.3177	0.4848	0.053*
C9	0.4741 (3)	0.16797 (14)	0.16067 (10)	0.0533 (4)
C10	0.4706 (4)	0.28905 (17)	0.15462 (13)	0.0741 (5)
H10	0.5715	0.3230	0.1986	0.089*
C11	0.3151 (6)	0.3616 (2)	0.08225 (17)	0.1031 (8)
H11	0.3100	0.4445	0.0786	0.124*
C12	0.1710 (6)	0.3140 (3)	0.01704 (17)	0.1147 (11)
H12	0.0684	0.3637	−0.0315	0.138*
C13	0.1767 (5)	0.1937 (3)	0.02275 (16)	0.1095 (9)
H13	0.0779	0.1608	−0.0224	0.131*
C14	0.3273 (5)	0.1185 (2)	0.09482 (13)	0.0801 (5)
H14	0.3291	0.0355	0.0986	0.096*
C15	1.9818 (4)	−0.57121 (15)	0.31744 (14)	0.0673 (5)
H15A	2.1107	−0.5307	0.3520	0.101*
H15B	2.0859	−0.6204	0.2810	0.101*
H15C	1.8588	−0.6211	0.3627	0.101*
N1	0.6337 (3)	0.08887 (13)	0.23256 (9)	0.0638 (4)
H1N	0.7673	0.0485	0.2118	0.077*
N2	0.7574 (2)	−0.01767 (10)	0.38096 (8)	0.0444 (3)
H2N	0.7494	−0.0302	0.4432	0.053*
N3	0.9333 (2)	−0.08853 (10)	0.33659 (8)	0.0436 (3)
O1	1.1397 (3)	−0.17907 (11)	0.18946 (7)	0.0654 (3)
H1O	1.0391	−0.1355	0.2157	0.098*
O2	1.8185 (2)	−0.48431 (10)	0.25302 (8)	0.0623 (3)
S1	0.37321 (8)	0.14895 (3)	0.38499 (3)	0.05153 (15)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0420 (7)	0.0420 (7)	0.0416 (7)	0.0050 (6)	0.0008 (5)	−0.0114 (6)
C2	0.0418 (7)	0.0435 (7)	0.0431 (7)	0.0055 (6)	0.0023 (6)	−0.0103 (6)
C3	0.0365 (7)	0.0367 (7)	0.0447 (7)	0.0003 (5)	0.0032 (5)	−0.0098 (5)
C4	0.0455 (7)	0.0412 (7)	0.0429 (7)	0.0056 (6)	0.0012 (6)	−0.0054 (6)
C5	0.0577 (9)	0.0515 (8)	0.0429 (8)	0.0089 (7)	0.0071 (6)	−0.0124 (6)
C6	0.0415 (7)	0.0391 (7)	0.0570 (8)	0.0027 (6)	0.0083 (6)	−0.0136 (6)
C7	0.0425 (7)	0.0418 (7)	0.0542 (8)	0.0076 (6)	−0.0038 (6)	−0.0089 (6)
C8	0.0460 (7)	0.0455 (8)	0.0430 (7)	0.0051 (6)	−0.0014 (6)	−0.0118 (6)
C9	0.0574 (9)	0.0637 (10)	0.0365 (7)	0.0174 (7)	0.0066 (6)	−0.0062 (6)
C10	0.0951 (13)	0.0663 (11)	0.0599 (10)	0.0216 (10)	0.0044 (9)	−0.0119 (8)
C11	0.145 (2)	0.0838 (15)	0.0679 (14)	0.0565 (15)	0.0207 (14)	0.0094 (11)
C12	0.1098 (19)	0.161 (3)	0.0539 (13)	0.0687 (19)	0.0109 (12)	0.0215 (15)
C13	0.0959 (17)	0.176 (3)	0.0514 (12)	0.0026 (18)	−0.0183 (11)	−0.0108 (15)
C14	0.0984 (14)	0.0874 (14)	0.0524 (10)	−0.0047 (11)	−0.0009 (10)	−0.0086 (9)
C15	0.0602 (10)	0.0570 (10)	0.0842 (12)	0.0223 (8)	0.0091 (9)	−0.0144 (9)
N1	0.0761 (9)	0.0729 (9)	0.0407 (7)	0.0394 (7)	0.0047 (6)	−0.0097 (6)
N2	0.0461 (6)	0.0470 (7)	0.0403 (6)	0.0141 (5)	0.0034 (5)	−0.0100 (5)
N3	0.0427 (6)	0.0422 (6)	0.0467 (6)	0.0085 (5)	0.0049 (5)	−0.0117 (5)
O1	0.0807 (8)	0.0710 (7)	0.0427 (6)	0.0338 (6)	−0.0051 (5)	−0.0086 (5)
O2	0.0645 (7)	0.0565 (6)	0.0679 (7)	0.0223 (5)	0.0098 (5)	−0.0188 (5)
S1	0.0608 (2)	0.0498 (2)	0.0441 (2)	0.02026 (17)	0.00687 (16)	−0.01125 (16)

Geometric parameters (Å, º)

C1—N1	1.3331 (18)	C9—N1	1.4249 (19)
C1—N2	1.3441 (17)	C10—C11	1.385 (3)
C1—S1	1.6768 (13)	C10—H10	0.9300
C2—N3	1.2797 (17)	C11—C12	1.348 (4)
C2—C3	1.4514 (17)	C11—H11	0.9300
C2—H2	0.9300	C12—C13	1.348 (4)
C3—C8	1.3916 (18)	C12—H12	0.9300
C3—C4	1.4000 (19)	C13—C14	1.383 (3)
C4—O1	1.3551 (17)	C13—H13	0.9300
C4—C5	1.3802 (19)	C14—H14	0.9300
C5—C6	1.381 (2)	C15—O2	1.423 (2)
C5—H5	0.9300	C15—H15A	0.9600
C6—O2	1.3618 (16)	C15—H15B	0.9600
C6—C7	1.384 (2)	C15—H15C	0.9600
C7—C8	1.3823 (19)	N1—H1N	0.8600
C7—H7	0.9300	N2—N3	1.3812 (15)
C8—H8	0.9300	N2—H2N	0.8600
C9—C10	1.356 (2)	O1—H1O	0.8200
C9—C14	1.373 (2)
N1—C1—N2	115.97 (12)	C11—C10—H10	120.3
N1—C1—S1	124.46 (10)	C12—C11—C10	121.0 (2)
N2—C1—S1	119.57 (10)	C12—C11—H11	119.5
N3—C2—C3	122.02 (12)	C10—C11—H11	119.5
N3—C2—H2	119.0	C11—C12—C13	119.5 (2)
C3—C2—H2	119.0	C11—C12—H12	120.2
C8—C3—C4	117.58 (12)	C13—C12—H12	120.2
C8—C3—C2	119.39 (12)	C12—C13—C14	120.9 (2)
C4—C3—C2	123.03 (12)	C12—C13—H13	119.5
O1—C4—C5	117.53 (12)	C14—C13—H13	119.5
O1—C4—C3	121.81 (12)	C9—C14—C13	119.1 (2)
C5—C4—C3	120.66 (13)	C9—C14—H14	120.4
C4—C5—C6	120.32 (13)	C13—C14—H14	120.4
C4—C5—H5	119.8	O2—C15—H15A	109.5
C6—C5—H5	119.8	O2—C15—H15B	109.5
O2—C6—C5	115.28 (13)	H15A—C15—H15B	109.5
O2—C6—C7	124.30 (13)	O2—C15—H15C	109.5
C5—C6—C7	120.42 (12)	H15A—C15—H15C	109.5
C8—C7—C6	118.76 (13)	H15B—C15—H15C	109.5
C8—C7—H7	120.6	C1—N1—C9	127.14 (12)
C6—C7—H7	120.6	C1—N1—H1N	116.4
C7—C8—C3	122.26 (13)	C9—N1—H1N	116.4
C7—C8—H8	118.9	C1—N2—N3	121.11 (11)
C3—C8—H8	118.9	C1—N2—H2N	119.4
C10—C9—C14	120.08 (16)	N3—N2—H2N	119.4
C10—C9—N1	121.90 (15)	C2—N3—N2	116.46 (11)
C14—C9—N1	118.00 (16)	C4—O1—H1O	109.5
C9—C10—C11	119.3 (2)	C6—O2—C15	118.18 (13)
C9—C10—H10	120.3

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···N3	0.82	1.94	2.6642 (15)	146
C13—H13···O1^i	0.93	2.54	3.387 (2)	151
C14—H14···O1^ii	0.93	2.67	3.487 (3)	147
N2—H2N···S1^iii	0.86	2.58	3.3862 (12)	156

Symmetry codes: (i) −x+1, −y, −z; (ii) x−1, y, z; (iii) −x+1, −y, −z+1.