Crystal structure of rac-3-[2,3-bis­(phenyl­sulfan­yl)-3H-indol-3-yl]propanoic acid

Noland, W.E.; Brown, C.D.; Bisel, A.M.; Schneerer, A.K.; Tritch, K.J.

doi:10.1107/S2056989015020241

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ISSN: 2056-9890

Volume 71| Part 11| November 2015| Pages 1414-1417

https://doi.org/10.1107/S2056989015020241

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Crystal structure of rac-3-[2,3-bis(phenylsulfanyl)-3H-indol-3-yl]propanoic acid

Wayland E. Noland,^a ^* Christopher D. Brown,^a Amanda M. Bisel,^a Andrew K. Schneerer ^a and Kenneth J. Tritch ^a

^aDepartment of Chemistry, University of Minnesota, Minneapolis, MN 55455-0431, USA
^*Correspondence e-mail: nolan001@umn.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 18 October 2015; accepted 26 October 2015; online 31 October 2015)

The title compound, C₂₃H₁₉NO₂S₂, was obtained as an unexpected regioisomer from an attempted synthesis of an intermediate for a substituent-effect study on ergot alkaloids. This is the first report of a 1H-indole monothioating at the 2- and 3-positions to give a 3H-indole. In the crystal, the acid H atom is twisted roughly 180° from the typical carboxy conformation and forms centrosymmetric O—H⋯N hydrogen-bonded dimers with the indole N atom of an inversion-related molecule. Together with a weak C—H⋯O hydrogen bond involving the carbonyl O atom, chains are formed along [100].

Keywords: crystal structure; Uhle's ketone; ergot; 3H-indole; thioation; O—H⋯N hydrogen bond.

CCDC reference: 1433300

1. Chemical context

The ergot alkaloids, a family of natural and synthetic compounds based on a tetracyclic skeleton [(2), Fig. 1], have been long known to exhibit various pharmacological activities (Hofmann, 1978 ). Examples include pergolide (Gilbert et al., 2000 ), bromocriptine (Weber et al., 1981 ), and cabergoline (Dosa et al., 2013 ), which have been used as treatments for Tourette's syndrome, psoriasis, and Parkinson's disease, respectively. Uhle's ketone (3) is a commonly used intermediate in the synthesis of some ergot alkaloids (Moldvai et al., 2004 ; Uhle, 1951 ).

Figure 1
The ergot alkaloid skeleton, (2), Uhle's ketone, (3), the intended product, (4), and the synthesis of the title compound (bottom row).

Our group envisioned the synthesis of novel Uhle's ketone derivatives bearing a reductively removable thio functionality at the 1- or 2-position to facilitate study of substituent effects at the 12–14 positions of several ergot alkaloids. 1,2-Bis(phenylthio)indole-3-propanoic acid (4) was a planned intermediate. However, phenylthioation and hydrolysis of methyl indole-3-propanoate (5) gave the title compound (1) as the only observed bisthioation product. 2,3-bis(thio)-3H-indoles such as (1) have not previously been reported as a product of 3-alkylindoles reacting with sulfenyl chlorides.

2. Structural commentary

The molecular structure of the title compound is shown in Fig. 2. The O1—H1O bond is syn-periplanar with C1—C2 (Fig. 3), in contrast to the anti-periplanar hydroxyl conformation usually observed in carboxyl groups. This is a consequence of an O1—H1O⋯N1 hydrogen bond (Table 1; §3). The remaining structural features are typical. The atoms of the indole unit (N1/C4–C11) have an r.m.s. deviation of 0.010 (2) Å from the mean plane, with quaternary carbon C4 only 0.012 (2) Å out of plane. The O1/C1–C4/S2/C18 (O1–C18) chain adopts a staggered conformation whose plane of best fit is inclined by 87.97 (8)° to that of the indole unit. Phenyl ring C18–C23 is inclined by 79.39 (10)° to the mean plane of the O1–C18 chain. Phenyl ring C12–C17 ring is inclined by 71.91 (7)° to the mean plane of the indole unit (Fig. 2). The C12—S1 bond is syn-periplanar with bond N1=C11, supporting conjugation between atom S1 and the indole system.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1ⁱ	0.84	1.96	2.7622 (18)	159
C3—H3A⋯O2ⁱⁱ	0.99	2.57	3.356 (2)	136
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+2, -y+1, -z+1.

Figure 2
The molecular structure of the title compound, showing the atom labeling. Displacement ellipsoids are drawn at the 50% probability level.

Figure 3
A view along [04 $[\overline{3}]$ ] of the O1—H1O⋯N1 hydrogen-bonded inversion dimer. The C12–C17 ring has been omitted for clarity.

3. Supramolecular features

In the crystal, an O1—H1O⋯N1 hydrogen bond (Table 1) forms inversion dimers with an R₂²(16) ring motif (Fig. 3). Molecules are also linked by a non-classical C3—H3A⋯O2 hydrogen bond, forming inversion dimers with an R₂²(10) motif (Fig. 4). Collectively, these interactions form chains along [100].

Figure 4
A view along [0 $[\overline{3}]$ 4] of the C3—H3A⋯O2 hydrogen-bonded inversion dimer.

4. Database survey

A search was performed for variously substituted 3H-indoles in the Cambridge Structural Database (CSD, Version 5.36, update 3; Groom & Allen, 2014 ). No entries were found containing a 3-thio or 3-propanoic functionality. Three examples of 2-thio-3H-indoles were found. Spiro-fused cyclohexanone (7) contains a 2-phenylthio group with similar geometry as is found in the title compound (Fig. 5; Feldman & Nuriye, 2009 ). The long chain in chlorotriester (8) is primarily staggered and normal to the indole unit, akin to the title compound (Novikov et al., 2003 ). The third example, (9), is a thiazolium-4-oxide (Moody et al., 2003 ).

Figure 5
The three 2-thio-3H-indoles found in the Cambridge Structural Database (CSD; Groom & Allen, 2014

5. Synthesis and crystallization

Methyl indole-3-propanoate (5) was prepared according to Pedras & Jha (2006 ), using p-toluenesulfonic acid in place of sulfuric acid. Benzenesulfenyl chloride (PhSCl) solution was prepared according to Li et al. (2013 ). In an argon atmosphere, methyl indole-3-propanoate (2.69 g) was dissolved in dichloromethane (30 ml) and then cooled in an ice bath. PhSCl solution (28 mmol, 32 ml) was added dropwise over 30 minutes. The resulting mixture was allowed to warm to room temperature and then was stirred for 2 h. Saturated NaHCO₃ solution (aq., 30 ml) was added, followed by extraction with dichloromethane (3 × 25 ml). The organic portion was dried with MgSO₄, concentrated, and then purified by column chromatography (SiO₂, 9:1 hexane–ethyl acetate), giving methyl 2,3-bis(phenylthio)-3H-indole-3-propanoate [(6), R_f = 0.41 in 2:1] as a yellow powder (3.29 g, 59%, m.p. 360-363 K); ¹H NMR (500 MHz, CD₂Cl₂) δ 7.572–7.553 (m, 2H), 7.455–7.416 (m, 4H), 7.222 (m, 1H), 7.194–7.171 (m, 4H), 7.104–7.073 (m, 2H), 7.045 (m, 1H), 3.563 (s, 3H), 2.647 (ddd, J = 13.8, 11.4, 5.1 Hz, 1H), 2.475 (ddd, J = 13.8, 11.2, 5.1 Hz, 1H), 2.174 (ddd, J = 16.3, 11.4, 5.1 Hz, 1H), 1.798 (ddd, J = 16.3, 11.2, 5.1 Hz, 1H); ¹³C NMR (126 MHz, CD₂Cl₂) δ 182.70 (1C), 175.84 (1C), 154.68 (1C), 139.60 (1C), 136.18 (2C), 135.44 (2C), 130.06 (1C), 129.95 (1C), 129.79 (2C), 129.74 (1C), 129.42 (1C), 128.85 (2C), 128.57 (1C), 125.31 (1C), 123.62 (1C), 119.50 (1C), 68.10 (1C), 52.14 (1C), 31.92 (1C), 29.55 (1C); IR (KBr, cm⁻¹) 3057 (w), 2956, 2926, 2851 (w), 1734 (s, C=O), 1508, 1440 (s), 1372, 1298 (O—CH₃), 1173, 744 (s), 689; MS (ESI, m/z) [M+H]⁺ calculated for C₂₄H₂₁NO₂S₂ 420.1086, found 420.1081.

Bisthioated ester [(6), 0.52 g] was dissolved in methanol (20 ml). KOH (0.12 g) and water (5 ml) were added. The resulting mixture was refluxed for 1 h and then cooled to room temperature. Hydrochloric acid was added drop wise until the reaction mixture pH reached 1. The resulting mixture was extracted with dichloromethane (3 × 25 ml). The organic portion was dried with MgSO₄ and then concentrated giving the title compound (1) as a pale-yellow powder (0.43 g, 90%, m.p. 443–445 K); R_f = 0.49 (SiO₂, 1:1 hexane–ethyl acetate); ¹H NMR (500 MHz, CD₂Cl₂; acid proton H1O not observed) δ 7.520–7.389 (m, 6H), 7.245–7.168 (m, 5H), 7.108–7.078 (m, 2H), 7.045 (m, 1H), 2.619 (ddd, J = 13.9, 11.8, 4.7 Hz, H3A), 2.447 (ddd, J = 13.9, 11.0, 5.0 Hz, H3B), 2.130 (ddd, J = 16.4, 11.8, 5.0 Hz, H2A), 1.734 (ddd, J = 16.4, 11.0, 4.7 Hz, H2B); ¹³C NMR (126 MHz, CD₂Cl₂) δ 183.24 (C11), 175.84 (C1), 154.38 (C10), 139.52 (C5), 136.20 (2C), 135.50 (2C), 130.16 (1C), 130.14 (1C), 129.91 (2C), 129.61 (1C), 128.90 (2C), 128.15 (1C), 127.48 (1C), 125.52 (1C), 123.65 (1C), 119.36 (1C), 67.93 (C4), 31.67 (C3), 29.18 (C2); IR (KBr, cm⁻¹) 3407 (O—H), 3056 (w), 2925, 2854 (w), 1745 (s, C=O), 1514, 1383, 746 (s), 689; MS (ESI, m/z) [M – H]⁻ calculated for C₂₃H₁₉NO₂S₂ 404.0784, found 404.0797.

Crystals of the title compound were grown by slow evaporation of a solution in dichloromethane at 270 K.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were placed in calculated positions and refined as riding atoms: O—H = 0.84 Å and C—H = 0.95–0.99 Å with U_iso(H) = 1.5U_eq(O1) for atom H1 and 1.2U_eq(C) for other H atoms.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₃H₁₉NO₂S₂
M_r	405.51
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	173
a, b, c (Å)	9.6498 (12), 9.8610 (12), 10.8812 (13)
α, β, γ (°)	87.626 (1), 79.331 (1), 76.022 (1)
V (Å³)	987.4 (2)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	0.29
Crystal size (mm)	0.23 × 0.12 × 0.10

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2007 )
T_min, T_max	0.698, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	11689, 4499, 3396
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.092, 1.06
No. of reflections	4499
No. of parameters	254
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.26
Computer programs: APEX2 and SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), Mercury (Macrae et al., 2008 ), enCIFer (Allen et al., 2004 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1433300

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015020241/su5230sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015020241/su5230Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015020241/su5230Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015), enCIFer (Allen et al., 2004) and publCIF (Westrip, 2010).

rac-3-[2,3-Bis(phenylsulfanyl)-3H-indol-3-yl]propanoic acid top

Crystal data top

C₂₃H₁₉NO₂S₂	F(000) = 424
M_r = 405.51	D_x = 1.364 Mg m⁻³
Triclinic, P1	Melting point: 444 K
a = 9.6498 (12) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.8610 (12) Å	Cell parameters from 2977 reflections
c = 10.8812 (13) Å	θ = 2.7–27.3°
α = 87.626 (1)°	µ = 0.29 mm⁻¹
β = 79.331 (1)°	T = 173 K
γ = 76.022 (1)°	Block, colourless
V = 987.4 (2) Å³	0.23 × 0.12 × 0.10 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	3396 reflections with I > 2σ(I)
Radiation source: sealed tube	R_int = 0.032
φ and ω scans	θ_max = 27.6°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −12→12
T_min = 0.698, T_max = 0.746	k = −12→12
11689 measured reflections	l = −14→14
4499 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.038	H-atom parameters constrained
wR(F²) = 0.092	w = 1/[σ²(F_o²) + (0.0362P)² + 0.1618P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
4499 reflections	Δρ_max = 0.27 e Å⁻³
254 parameters	Δρ_min = −0.26 e Å⁻³

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
S1	0.62197 (5)	0.45034 (5)	0.16673 (4)	0.03266 (13)
S2	0.92472 (5)	0.19331 (5)	0.20164 (4)	0.03283 (13)
O1	0.74866 (13)	0.71335 (13)	0.58120 (12)	0.0338 (3)
H1	0.6688	0.6928	0.6075	0.051*
O2	0.93299 (13)	0.65100 (13)	0.42699 (12)	0.0370 (3)
N1	0.54112 (14)	0.29215 (14)	0.36472 (13)	0.0251 (3)
C1	0.82262 (18)	0.62905 (17)	0.48697 (16)	0.0262 (4)
C2	0.76080 (18)	0.50855 (18)	0.46281 (16)	0.0289 (4)
H2A	0.6624	0.5453	0.4433	0.035*
H2B	0.7514	0.4515	0.5395	0.035*
C3	0.85486 (18)	0.41595 (17)	0.35510 (16)	0.0279 (4)
H3A	0.9532	0.3789	0.3747	0.033*
H3B	0.8644	0.4731	0.2784	0.033*
C4	0.79162 (17)	0.29341 (17)	0.33029 (15)	0.0258 (4)
C5	0.75579 (18)	0.20556 (17)	0.44228 (15)	0.0254 (4)
C6	0.84042 (19)	0.13254 (18)	0.52368 (17)	0.0310 (4)
H6	0.9401	0.1332	0.5147	0.037*
C7	0.7755 (2)	0.05780 (18)	0.61945 (17)	0.0350 (4)
H7	0.8320	0.0052	0.6757	0.042*
C8	0.6292 (2)	0.05935 (18)	0.63364 (17)	0.0350 (4)
H8	0.5872	0.0073	0.6994	0.042*
C9	0.54286 (19)	0.13564 (17)	0.55330 (16)	0.0295 (4)
H9	0.4424	0.1380	0.5637	0.035*
C10	0.60945 (18)	0.20787 (16)	0.45758 (15)	0.0251 (4)
C11	0.64132 (17)	0.34029 (17)	0.29370 (15)	0.0250 (4)
C12	0.43242 (19)	0.48511 (19)	0.16692 (15)	0.0295 (4)
C13	0.3474 (2)	0.6178 (2)	0.20041 (17)	0.0363 (4)
H13	0.3887	0.6865	0.2283	0.044*
C14	0.2017 (2)	0.6485 (2)	0.19258 (18)	0.0432 (5)
H14	0.1427	0.7391	0.2152	0.052*
C15	0.1417 (2)	0.5497 (2)	0.15248 (18)	0.0442 (5)
H15	0.0420	0.5726	0.1459	0.053*
C16	0.2255 (2)	0.4172 (2)	0.12167 (18)	0.0422 (5)
H16	0.1828	0.3482	0.0962	0.051*
C17	0.3717 (2)	0.3847 (2)	0.12777 (17)	0.0358 (4)
H17	0.4301	0.2939	0.1052	0.043*
C18	0.83442 (18)	0.06781 (19)	0.16376 (16)	0.0307 (4)
C19	0.7666 (2)	0.0890 (2)	0.06019 (18)	0.0444 (5)
H19	0.7669	0.1712	0.0115	0.053*
C20	0.6988 (3)	−0.0091 (3)	0.0277 (2)	0.0563 (6)
H20	0.6528	0.0057	−0.0433	0.068*
C21	0.6979 (2)	−0.1282 (2)	0.0980 (2)	0.0506 (6)
H21	0.6496	−0.1947	0.0764	0.061*
C22	0.7667 (2)	−0.1509 (2)	0.19934 (19)	0.0444 (5)
H22	0.7674	−0.2341	0.2467	0.053*
C23	0.8348 (2)	−0.05393 (19)	0.23299 (17)	0.0355 (4)
H23	0.8820	−0.0703	0.3034	0.043*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0282 (2)	0.0393 (3)	0.0309 (2)	−0.0096 (2)	−0.00598 (19)	0.0068 (2)
S2	0.0249 (2)	0.0364 (3)	0.0345 (3)	−0.00567 (19)	0.00119 (19)	−0.0076 (2)
O1	0.0281 (7)	0.0349 (7)	0.0405 (7)	−0.0121 (6)	−0.0035 (6)	−0.0088 (6)
O2	0.0303 (7)	0.0405 (8)	0.0426 (8)	−0.0175 (6)	0.0000 (6)	−0.0020 (6)
N1	0.0236 (7)	0.0249 (7)	0.0271 (7)	−0.0060 (6)	−0.0048 (6)	−0.0018 (6)
C1	0.0255 (9)	0.0273 (9)	0.0282 (9)	−0.0072 (7)	−0.0101 (7)	0.0035 (7)
C2	0.0246 (9)	0.0300 (9)	0.0326 (9)	−0.0104 (7)	−0.0011 (7)	−0.0025 (7)
C3	0.0223 (8)	0.0299 (9)	0.0325 (9)	−0.0089 (7)	−0.0038 (7)	−0.0017 (7)
C4	0.0208 (8)	0.0271 (9)	0.0279 (9)	−0.0035 (7)	−0.0027 (7)	−0.0034 (7)
C5	0.0262 (9)	0.0216 (8)	0.0274 (9)	−0.0041 (7)	−0.0033 (7)	−0.0047 (7)
C6	0.0290 (9)	0.0268 (9)	0.0361 (10)	−0.0031 (7)	−0.0075 (8)	−0.0026 (8)
C7	0.0397 (11)	0.0265 (9)	0.0368 (11)	0.0001 (8)	−0.0127 (8)	0.0012 (8)
C8	0.0449 (11)	0.0254 (9)	0.0337 (10)	−0.0089 (8)	−0.0050 (9)	0.0037 (8)
C9	0.0287 (9)	0.0239 (9)	0.0362 (10)	−0.0082 (7)	−0.0042 (8)	−0.0006 (7)
C10	0.0273 (9)	0.0212 (8)	0.0265 (9)	−0.0048 (7)	−0.0046 (7)	−0.0024 (7)
C11	0.0241 (8)	0.0231 (8)	0.0270 (9)	−0.0040 (7)	−0.0036 (7)	−0.0065 (7)
C12	0.0291 (9)	0.0360 (10)	0.0223 (9)	−0.0058 (8)	−0.0054 (7)	0.0048 (7)
C13	0.0371 (10)	0.0378 (11)	0.0320 (10)	−0.0065 (8)	−0.0043 (8)	0.0006 (8)
C14	0.0363 (11)	0.0459 (12)	0.0380 (11)	0.0020 (9)	0.0014 (9)	0.0029 (9)
C15	0.0280 (10)	0.0677 (15)	0.0333 (11)	−0.0099 (10)	−0.0007 (8)	0.0100 (10)
C16	0.0385 (11)	0.0565 (13)	0.0360 (11)	−0.0199 (10)	−0.0072 (9)	0.0033 (10)
C17	0.0376 (11)	0.0377 (11)	0.0327 (10)	−0.0090 (9)	−0.0075 (8)	0.0004 (8)
C18	0.0264 (9)	0.0330 (10)	0.0291 (9)	−0.0006 (7)	−0.0022 (7)	−0.0085 (8)
C19	0.0580 (14)	0.0411 (12)	0.0346 (11)	−0.0078 (10)	−0.0146 (10)	−0.0018 (9)
C20	0.0702 (16)	0.0599 (15)	0.0451 (13)	−0.0130 (12)	−0.0271 (12)	−0.0136 (11)
C21	0.0531 (14)	0.0479 (13)	0.0542 (14)	−0.0160 (11)	−0.0092 (11)	−0.0176 (11)
C22	0.0538 (13)	0.0347 (11)	0.0425 (12)	−0.0113 (10)	−0.0007 (10)	−0.0057 (9)
C23	0.0374 (10)	0.0328 (10)	0.0335 (10)	−0.0013 (8)	−0.0072 (8)	−0.0050 (8)

Geometric parameters (Å, º) top

S1—C11	1.7305 (17)	C8—H8	0.9500
S1—C12	1.7773 (18)	C9—C10	1.385 (2)
S2—C18	1.7767 (18)	C9—H9	0.9500
S2—C4	1.8493 (16)	C12—C17	1.383 (2)
O1—C1	1.328 (2)	C12—C13	1.389 (3)
O1—H1	0.8400	C13—C14	1.382 (3)
O2—C1	1.2040 (19)	C13—H13	0.9500
N1—C11	1.293 (2)	C14—C15	1.370 (3)
N1—C10	1.435 (2)	C14—H14	0.9500
C1—C2	1.504 (2)	C15—C16	1.378 (3)
C2—C3	1.525 (2)	C15—H15	0.9500
C2—H2A	0.9900	C16—C17	1.382 (3)
C2—H2B	0.9900	C16—H16	0.9500
C3—C4	1.533 (2)	C17—H17	0.9500
C3—H3A	0.9900	C18—C19	1.389 (3)
C3—H3B	0.9900	C18—C23	1.390 (2)
C4—C5	1.502 (2)	C19—C20	1.382 (3)
C4—C11	1.533 (2)	C19—H19	0.9500
C5—C6	1.379 (2)	C20—C21	1.375 (3)
C5—C10	1.386 (2)	C20—H20	0.9500
C6—C7	1.392 (2)	C21—C22	1.374 (3)
C6—H6	0.9500	C21—H21	0.9500
C7—C8	1.388 (3)	C22—C23	1.379 (3)
C7—H7	0.9500	C22—H22	0.9500
C8—C9	1.392 (2)	C23—H23	0.9500

C11—S1—C12	102.47 (8)	C9—C10—N1	126.35 (15)
C18—S2—C4	102.65 (8)	C5—C10—N1	111.96 (14)
C1—O1—H1	109.5	N1—C11—C4	114.43 (14)
C11—N1—C10	106.38 (14)	N1—C11—S1	127.16 (13)
O2—C1—O1	119.92 (15)	C4—C11—S1	118.40 (12)
O2—C1—C2	123.81 (16)	C17—C12—C13	120.40 (17)
O1—C1—C2	116.27 (14)	C17—C12—S1	120.78 (14)
C1—C2—C3	112.44 (13)	C13—C12—S1	118.72 (14)
C1—C2—H2A	109.1	C14—C13—C12	119.08 (19)
C3—C2—H2A	109.1	C14—C13—H13	120.5
C1—C2—H2B	109.1	C12—C13—H13	120.5
C3—C2—H2B	109.1	C15—C14—C13	120.61 (19)
H2A—C2—H2B	107.8	C15—C14—H14	119.7
C2—C3—C4	112.42 (13)	C13—C14—H14	119.7
C2—C3—H3A	109.1	C14—C15—C16	120.29 (19)
C4—C3—H3A	109.1	C14—C15—H15	119.9
C2—C3—H3B	109.1	C16—C15—H15	119.9
C4—C3—H3B	109.1	C15—C16—C17	119.99 (19)
H3A—C3—H3B	107.9	C15—C16—H16	120.0
C5—C4—C3	115.35 (14)	C17—C16—H16	120.0
C5—C4—C11	99.58 (13)	C16—C17—C12	119.61 (18)
C3—C4—C11	113.08 (13)	C16—C17—H17	120.2
C5—C4—S2	113.36 (11)	C12—C17—H17	120.2
C3—C4—S2	104.98 (11)	C19—C18—C23	119.20 (18)
C11—C4—S2	110.69 (11)	C19—C18—S2	119.45 (15)
C6—C5—C10	120.95 (16)	C23—C18—S2	121.31 (14)
C6—C5—C4	131.39 (15)	C20—C19—C18	120.20 (19)
C10—C5—C4	107.65 (14)	C20—C19—H19	119.9
C5—C6—C7	118.04 (17)	C18—C19—H19	119.9
C5—C6—H6	121.0	C21—C20—C19	120.1 (2)
C7—C6—H6	121.0	C21—C20—H20	119.9
C8—C7—C6	120.76 (17)	C19—C20—H20	119.9
C8—C7—H7	119.6	C22—C21—C20	119.9 (2)
C6—C7—H7	119.6	C22—C21—H21	120.0
C7—C8—C9	121.26 (17)	C20—C21—H21	120.0
C7—C8—H8	119.4	C21—C22—C23	120.6 (2)
C9—C8—H8	119.4	C21—C22—H22	119.7
C10—C9—C8	117.26 (16)	C23—C22—H22	119.7
C10—C9—H9	121.4	C22—C23—C18	119.89 (18)
C8—C9—H9	121.4	C22—C23—H23	120.1
C9—C10—C5	121.70 (16)	C18—C23—H23	120.1

O2—C1—C2—C3	0.9 (2)	C10—N1—C11—S1	−179.11 (12)
O1—C1—C2—C3	−178.65 (14)	C5—C4—C11—N1	−0.43 (18)
C1—C2—C3—C4	−179.85 (13)	C3—C4—C11—N1	−123.38 (16)
C2—C3—C4—C5	−52.58 (19)	S2—C4—C11—N1	119.15 (13)
C2—C3—C4—C11	61.13 (19)	C5—C4—C11—S1	178.90 (11)
C2—C3—C4—S2	−178.10 (12)	C3—C4—C11—S1	55.95 (17)
C18—S2—C4—C5	60.67 (13)	S2—C4—C11—S1	−61.52 (14)
C18—S2—C4—C3	−172.58 (11)	C12—S1—C11—N1	3.10 (17)
C18—S2—C4—C11	−50.24 (13)	C12—S1—C11—C4	−176.13 (12)
C3—C4—C5—C6	−57.2 (2)	C11—S1—C12—C17	−74.16 (15)
C11—C4—C5—C6	−178.58 (17)	C11—S1—C12—C13	109.44 (14)
S2—C4—C5—C6	63.8 (2)	C17—C12—C13—C14	−0.8 (3)
C3—C4—C5—C10	121.86 (15)	S1—C12—C13—C14	175.62 (14)
C11—C4—C5—C10	0.53 (16)	C12—C13—C14—C15	0.1 (3)
S2—C4—C5—C10	−117.07 (13)	C13—C14—C15—C16	1.3 (3)
C10—C5—C6—C7	1.9 (2)	C14—C15—C16—C17	−1.8 (3)
C4—C5—C6—C7	−179.11 (16)	C15—C16—C17—C12	1.1 (3)
C5—C6—C7—C8	−1.2 (3)	C13—C12—C17—C16	0.2 (3)
C6—C7—C8—C9	−0.2 (3)	S1—C12—C17—C16	−176.11 (14)
C7—C8—C9—C10	1.0 (3)	C4—S2—C18—C19	100.86 (16)
C8—C9—C10—C5	−0.4 (2)	C4—S2—C18—C23	−81.59 (15)
C8—C9—C10—N1	179.83 (15)	C23—C18—C19—C20	0.9 (3)
C6—C5—C10—C9	−1.1 (3)	S2—C18—C19—C20	178.48 (16)
C4—C5—C10—C9	179.70 (15)	C18—C19—C20—C21	0.2 (3)
C6—C5—C10—N1	178.71 (14)	C19—C20—C21—C22	−1.2 (3)
C4—C5—C10—N1	−0.51 (18)	C20—C21—C22—C23	1.2 (3)
C11—N1—C10—C9	−179.99 (16)	C21—C22—C23—C18	−0.2 (3)
C11—N1—C10—C5	0.23 (18)	C19—C18—C23—C22	−0.9 (3)
C10—N1—C11—C4	0.15 (18)	S2—C18—C23—C22	−178.43 (14)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1ⁱ	0.84	1.96	2.7622 (18)	159
C3—H3A···O2ⁱⁱ	0.99	2.57	3.356 (2)	136

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+2, −y+1, −z+1.

Acknowledgements

The authors thank Victor G. Young, Jr (X-Ray Crystallographic Laboratory, University of Minnesota) for assistance with the crystal structure analysis, and the Wayland E. Noland Research Fellowship Fund at the University of Minnesota Foundation for generous financial support of this work.

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