3-De­oxy-1,2-di-O-isopropyl­idene-5-O-tosyl-d-threo-pentofuran­ose

Doboszewski, B.; Silva, M.J. e; Nazarenko, A.Y.; Nemykin, V.N.

doi:10.1107/S1600536812010884

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 4| April 2012| Pages o1109-o1110

doi:10.1107/S1600536812010884

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3-Deoxy-1,2-di-O-isopropylidene-5-O-tosyl-D-threo-pentofuranose

Bogdan Doboszewski,^a Maria J. e Silva,^b Alexander Y. Nazarenko ^c ^* and Victor N. Nemykin ^d

^aDepartamento de Química, Universidade Federal Rural de Pernambuco, 52171-900 Recife, PE, Brazil, ^bDepartamento de Farmácia, Universidade Federal do Rio Grande do Norte, 59010-180 Natal, RN, Brazil, ^cChemistry Department, State University of New York, College at Buffalo, 1300 Elmwood Ave, Buffalo, NY 14222-1095, USA, and ^dDepartment of Chemistry & Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812-2496 USA
^*Correspondence e-mail: nazareay@buffalostate.edu

(Received 10 March 2012; accepted 12 March 2012; online 17 March 2012)

In the crystal structure of the title compound, C₁₅H₂₀O₆S, the two independent molecules crystalllize in a chiral setting with two different conformations, twisted ⁴T₃ and envelope ⁴E, for the furanose rings. Weak C—H⋯O contacts strengthen the crystal structure.

Related literature

For the syntheses of this and similar compounds, see: Cox et al. (1997 ); Dahlman et al. (1986 ); Doboszewski & Herdewijn (1996 , 2008 ). For conformations of five-membered rings, see: Cremer & Pople (1975 ); Boeyens & Dobson (1987 ). For weak C—H⋯O contacts, see: Desiraju & Steiner (1999 ). For analysis of absolute structure, see: Flack (1983 ); Hooft et al. (2008 ); Tipson (1944 ); Fieser & Fieser (1967 ) describe tosylation reactions. For standard bond length data, see: Allen (2002 ).

Experimental

Crystal data

C₁₅H₂₀O₆S
M_r = 328.37
Monoclinic, P 2₁
a = 10.9397 (1) Å
b = 9.4251 (1) Å
c = 15.4833 (10) Å
β = 96.414 (7)°
V = 1586.46 (10) Å³
Z = 4
Cu Kα radiation
μ = 2.06 mm⁻¹
T = 123 K
0.2 × 0.2 × 0.18 mm

Data collection

Rigaku R-AXIS RAPID II imaging plate diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.55, T_max = 0.65
14179 measured reflections
4917 independent reflections
4440 reflections with I > 2σ(I)
R_int = 0.037

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.087
S = 1.04
4917 reflections
404 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.26 e Å⁻³
Absolute structure: Flack (1983), 2059 Friedel pairs
Flack parameter: 0.005 (12)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯O5ⁱ	1.00	2.48	3.390 (3)	152
C5—H5B⋯O3	0.99	2.56	3.196 (3)	122
C11—H11⋯O12ⁱⁱ	0.95	2.44	3.163 (3)	133
C24—H24⋯O15ⁱⁱⁱ	1.00	2.42	3.315 (3)	148
C28—H28C⋯O6^iv	0.98	2.54	3.471 (3)	159
Symmetry codes: (i) $[-x+1, y-{\script{1\over 2}}, -z+2]$ ; (ii) $[-x, y+{\script{1\over 2}}, -z+1]$ ; (iii) $[-x+1, y-{\script{1\over 2}}, -z+1]$ ; (iv) x, y-1, z-1.

Data collection: CrystalClear-SM Expert (Rigaku, 2009 ); cell refinement: HKL-2000 (Otwinowski & Minor, 1997 ); data reduction: CrystalClear-SM Expert; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999 ) and Mercury (Macrae et al., 2008 ); software used to prepare material for publication: PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812010884/zl2463sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812010884/zl2463Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812010884/zl2463Isup3.cdx

checkCIF report

Comment top

D- and L-arabinose are very convenient chiral-pool substrates for stereoselective synthesis since both of them are commercially available, reasonably priced, and easy to functionalize in two steps to form 5-O-t-butyldiphenylsilyl-1,2-O-isopropylidene furanose or its L-enantiomer (Dahlman et al., 1986; Doboszewski & Herdewijn, 2008). Both enantiomers have been previously used in the synthesis of degradation products of the antibiotic Batumin/Kalimantacin A (Doboszewski & Herdewijn, 2008), to obtain branched-chain pyranosyl nucleosides (Doboszewski & Herdewijn, 1996) and C-hydroxymethylpentose present in lipopolysaccharides of Coxiella brunetii (Dahlman et al., 1986), among others. Our current interest in arabinose stems from a possibility to convert it into the general substrates 3-deoxy-1,2-di-O-isopropylidene-5-O-tosyl-D-threo-pentofuranose and 3-deoxy-1,2-di-O-isopropylidene-5-O-butyldiphenylsilyl-D-threo-pentofuranose to be used in further transformations. A synthesis scheme for both these compounds is shown in Figure 1. We wanted to firmly establish their structures, due to a possibility of enolization of the ulose and concomitant inversion of configuration at the C4 position during formation of the tosylhydrazone.

A correct absolute structure of the title compound was important for the further synthetic work. Because of that, we have selected Cu Kα radiation to ensure unambigous determination of the absolute structure.

In the crystal structure of the title compound (Fig.2), there are two crystallographically independent molecules, A (C1–C15, O1–O6, S1) and B (C21–C35, O11–O16, S2), in which all bond lengths and bond angles have standard dimensions. The six-membered phenyl rings in both molecules are flat within 0.01 Å.

It is visually obvious (Fig. 3 and Fig. 4) that the conformations of the five-membered rings differs in the two independent molecules A and B. A quantitative analysis of the ring conformations was performed using the method of Cremer and Pople (Cremer & Pople, 1975; Boeyens & Dobson, 1987) for the calculation of parameters of puckering. In molecule A, the polar parameters for the furanose ring and adjacent five membered ring are Q = 0.289 (3) and 0.312 (2) Å, Φ = 122.9 (5)° and 119.7 (5)°, respectively. These suggest a twisted ⁴T₃ conformation for the furanose ring (ideal Φ = 126°), slightly distorted towards envelope (Φ = 108°). The substituent ring also has a twisted conformation (Fig. 3).

In molecule B (Fig. 4), the polar parameters for the furanose ring and the corresponding five membered ring are Q = 0.292 (3) and 0.361 (2) Å, Φ = 142.1 (5)° and 143.9 (4)°. These suggest an envelope conformation (ideal Φ = 144°) for both rings, with atoms C(24) and C(26) in the corners of the respective envelopes (⁴E for the furanose ring).

In the structure of 1,2-di-O-isopropylidene-5-O-tosyl-D-xylofuranose which differs from the title compound in one hydroxy group, the polar parameters are Q = 0.352 (3) Å, Φ = 288.8 (5)°; see refcodes RUWDES and RUWDES01 (Cox et al., 1997). This makes the conformation an almost exact ³E envelope, but with a different carbon atom in the corner than in the case described here. Obviously, the furanose ring conformation is highly flexible and is easily influenced even by weak intermolecular interactions.

A short intramolecular contact is present between sulfonyl O atoms O5 and O15 and neighboring hydrogen atoms of the adjacent respective phenyl rings (see Table 1). This is quite common for aryl sulfonyls and the majority of these compounds exhibit these intramolecular interactions (mean H···O distance is 2.533 Å for more than 2500 analogous structures listed in the Cambridge Structural Database (Allen, 2002)). It may additionaly stabilize the conformation of the molecule. Only weak intermolecular C—H···O contacts (Table 1) exist between neighboring molecules.

Related literature top

For the syntheses of this and similar compounds, see: Cox et al. (1997); Dahlman et al. (1986); Doboszewski & Herdewijn (1996, 2008). For conformations of five-membered rings, see: Cremer & Pople (1975); Boeyens & Dobson (1987). For weak C—H···O contacts, see: Desiraju & Steiner (1999). For analysis of absolute structure, see: Flack (1983); Hooft et al. (2008).Tipson (1944); Fieser & Fieser (1967) describe tosylation reactions. For standard-bond length data, see: Allen (2002).

Experimental top

Title compound was obtained as a product of a multi-step synthetic procedure (Doboszewski & Herdewijn, 2008; see Fig. 1). The tosylation of the previously synthesized 3-deoxy-1,2-di-O-isopropylidene-5-O-t-butyldiphenylsilyl-D-threo-pentofuranose by tosyl chloride in dry pyridine following standard reaction conditions (Tipson, 1944; Fieser & Fieser, 1967) produced the title compound in quantitative (near 100%) yield. Crystals suitable for X-ray diffraction experiment were crystallized from a hexane - diethyl ether mixture.

R_f 0.36 in hexane- EtOAc 2:1; mp. 346–348 K (from Et₂O-hexane); α_D +42.8° (c 1.6 g/100mL, CHCl₃); exact mass (electrospray): calc. for C₁₅H₂₀O₆S + Na⁺= 351.0873, found 351.0872; ¹H NMR (300 MHz, CDCl₃): 7.80(d, J=8.3 Hz,2H), 7.34(d, J=8.3 Hz, 2H), 5.76(d, J=3.7 Hz, 1H), 4.69(t, J=4.6 Hz, 1H), 4.36(dddd, J=2.0 Hz, 6.5 Hz, 6.5 Hz, 8.4 Hz, 1H), 4.19(dd, J= 6.9 Hz, 9.7 Hz, 1H), 4.11(dd,J=6.6 Hz, 9.7 Hz, 1H), 2,44(s, 3H), 2.17(ddd, J=5.7 Hz, 8.5 Hz, 14.4 Hz, 1H), 2.04(dd, J=1.6 Hz, 14.5 Hz, 1H), 1.33 and 1.25(two s, 3H each); ¹³C NMR (75 MHz, CDCl₃): 145.01, 132.96, 129.99, 128.16, 112.32, 106.94, 80.33, 77.91, 71.34, 33.68, 26.74, 25.70, 21.73. FTIR (diamond ATR): 2985, 2944, 1598, 1381, 1188, 991, 953, 705, 574 cm^-1.

Structure description top

For the syntheses of this and similar compounds, see: Cox et al. (1997); Dahlman et al. (1986); Doboszewski & Herdewijn (1996, 2008). For conformations of five-membered rings, see: Cremer & Pople (1975); Boeyens & Dobson (1987). For weak C—H···O contacts, see: Desiraju & Steiner (1999). For analysis of absolute structure, see: Flack (1983); Hooft et al. (2008).Tipson (1944); Fieser & Fieser (1967) describe tosylation reactions. For standard-bond length data, see: Allen (2002).

Computing details top

Data collection: CrystalClear-SM Expert (Rigaku, 2009); cell refinement: HKL-2000 (Otwinowski & Minor, 1997); data reduction: CrystalClear-SM Expert (Rigaku, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999) and Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. Scheme of the synthetic route leading to title compound.
	Fig. 2. ORTEP view of two independent 3-deoxy-1,2-di-O-isopropylidene-5-O-tosyl-D-threo-pentofuranose molecules (A and B) with displacement ellipsoids drawn at the 50% probability level.
	Fig. 3. Twisted conformations of the five-membered rings in molecule A. Planes are drawn through atoms O1, C1, and C2 (yellow) and O2, C1, and C2 (green).
	Fig. 4. Envelope conformations of the five-membered rings in molecule B. Mean planes through atoms O11, C1, C2, C4 (yellow) and C1, C2, O2, and O3 (green).
	Fig. 5. View of the title compound showing displacement ellipsoids at the 50% probability level.

3-Deoxy-1,2-di-O-isopropylidene-5-O-tosyl-D-threo- pentofuranose top

Crystal data top

C₁₅H₂₀O₆S	F(000) = 696
M_r = 328.37	D_x = 1.375 Mg m⁻³
Monoclinic, P2₁	Melting point: 347(1) K
Hall symbol: P 2yb	Cu Kα radiation, λ = 1.54187 Å
a = 10.9397 (1) Å	Cell parameters from 14102 reflections
b = 9.4251 (1) Å	θ = 2.9–68.3°
c = 15.4833 (10) Å	µ = 2.06 mm⁻¹
β = 96.414 (7)°	T = 123 K
V = 1586.46 (10) Å³	Block, colourless
Z = 4	0.2 × 0.2 × 0.18 mm

Data collection top

Rigaku R-AXIS RAPID II imaging plate diffractometer	4917 independent reflections
Radiation source: fine-focus sealed tube	4440 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
Detector resolution: 10.0 pixels mm^-1	θ_max = 65.5°, θ_min = 2.9°
ω scans	h = −12→12
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −8→11
T_min = 0.55, T_max = 0.65	l = −18→18
14179 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.034	H-atom parameters constrained
wR(F²) = 0.087	w = 1/[σ²(F_o²) + (0.0495P)²] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
4917 reflections	Δρ_max = 0.30 e Å⁻³
404 parameters	Δρ_min = −0.26 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 2059 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.005 (12)

Crystal data top

C₁₅H₂₀O₆S	V = 1586.46 (10) Å³
M_r = 328.37	Z = 4
Monoclinic, P2₁	Cu Kα radiation
a = 10.9397 (1) Å	µ = 2.06 mm⁻¹
b = 9.4251 (1) Å	T = 123 K
c = 15.4833 (10) Å	0.2 × 0.2 × 0.18 mm
β = 96.414 (7)°

Data collection top

Rigaku R-AXIS RAPID II imaging plate diffractometer	4917 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	4440 reflections with I > 2σ(I)
T_min = 0.55, T_max = 0.65	R_int = 0.037
14179 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	H-atom parameters constrained
wR(F²) = 0.087	Δρ_max = 0.30 e Å⁻³
S = 1.04	Δρ_min = −0.26 e Å⁻³
4917 reflections	Absolute structure: Flack (1983), 2059 Friedel pairs
404 parameters	Absolute structure parameter: 0.005 (12)
1 restraint

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.

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 (Å²) top

	x	y	z	U_iso*/U_eq
S1	0.32715 (6)	0.65201 (7)	0.88376 (4)	0.03365 (17)
O1	0.25715 (16)	0.2054 (2)	0.92121 (10)	0.0390 (5)
O2	0.16307 (15)	0.1633 (3)	0.78122 (10)	0.0473 (6)
O3	0.35387 (15)	0.1347 (2)	0.74148 (10)	0.0349 (4)
O4	0.32552 (16)	0.49623 (19)	0.92025 (10)	0.0328 (4)
O5	0.45192 (17)	0.6937 (2)	0.87784 (11)	0.0427 (5)
O6	0.25396 (18)	0.7302 (2)	0.93686 (11)	0.0473 (5)
C1	0.2332 (2)	0.1040 (3)	0.85455 (16)	0.0366 (7)
H1	0.1914	0.0186	0.8760	0.044*
C2	0.3566 (2)	0.0634 (3)	0.82292 (16)	0.0367 (7)
H2	0.3673	−0.0415	0.8178	0.044*
C3	0.4515 (2)	0.1298 (3)	0.88914 (16)	0.0396 (7)
H3A	0.5227	0.1651	0.8612	0.048*
H3B	0.4809	0.0607	0.9350	0.048*
C4	0.3831 (2)	0.2518 (3)	0.92672 (15)	0.0349 (7)
H4	0.4155	0.2653	0.9892	0.042*
C5	0.3957 (2)	0.3885 (3)	0.87844 (16)	0.0344 (6)
H5A	0.4833	0.4164	0.8814	0.041*
H5B	0.3628	0.3775	0.8166	0.041*
C6	0.2273 (2)	0.1439 (3)	0.70647 (15)	0.0316 (6)
C7	0.2104 (3)	0.2734 (3)	0.64975 (17)	0.0452 (7)
H7A	0.2584	0.2630	0.6004	0.068*
H7B	0.2385	0.3574	0.6835	0.068*
H7C	0.1231	0.2841	0.6283	0.068*
C8	0.1844 (3)	0.0099 (3)	0.65937 (18)	0.0473 (8)
H8A	0.0972	0.0190	0.6373	0.071*
H8B	0.1952	−0.0707	0.6995	0.071*
H8C	0.2327	−0.0059	0.6106	0.071*
C9	0.2509 (2)	0.6412 (3)	0.77785 (14)	0.0286 (6)
C10	0.1249 (2)	0.6169 (3)	0.76511 (16)	0.0339 (7)
H10	0.0797	0.6031	0.8133	0.041*
C11	0.0667 (2)	0.6132 (3)	0.68185 (16)	0.0346 (7)
H11	−0.0194	0.5968	0.6731	0.042*
C12	0.1305 (2)	0.6327 (3)	0.61033 (15)	0.0314 (6)
C13	0.2563 (2)	0.6543 (3)	0.62421 (14)	0.0304 (6)
H13	0.3016	0.6666	0.5759	0.037*
C14	0.3168 (2)	0.6582 (3)	0.70733 (14)	0.0293 (6)
H14	0.4033	0.6725	0.7161	0.035*
C15	0.0639 (3)	0.6296 (4)	0.51920 (16)	0.0457 (8)
H15A	0.1056	0.5634	0.4834	0.069*
H15B	0.0643	0.7248	0.4938	0.069*
H15C	−0.0212	0.5985	0.5214	0.069*
S2	0.37237 (6)	0.33823 (7)	0.40722 (4)	0.03353 (17)
O11	0.20451 (16)	−0.0793 (2)	0.39873 (10)	0.0370 (5)
O12	0.15723 (16)	−0.0483 (2)	0.25011 (10)	0.0363 (5)
O13	0.32440 (15)	−0.1684 (2)	0.22108 (10)	0.0369 (5)
O14	0.33657 (14)	0.1829 (2)	0.43291 (10)	0.0350 (4)
O15	0.50001 (15)	0.3417 (2)	0.39625 (11)	0.0383 (5)
O16	0.32592 (17)	0.4259 (2)	0.47060 (11)	0.0433 (5)
C21	0.1763 (2)	−0.1485 (3)	0.31885 (15)	0.0373 (7)
H21	0.1038	−0.2127	0.3199	0.045*
C22	0.2916 (2)	−0.2316 (3)	0.29894 (15)	0.0356 (7)
H22	0.2747	−0.3354	0.2916	0.043*
C23	0.3858 (2)	−0.2014 (3)	0.37619 (16)	0.0397 (7)
H23A	0.4677	−0.1826	0.3571	0.048*
H23B	0.3925	−0.2824	0.4172	0.048*
C24	0.3365 (2)	−0.0699 (3)	0.41833 (16)	0.0328 (6)
H24	0.3581	−0.0759	0.4827	0.039*
C25	0.3872 (2)	0.0657 (3)	0.38602 (15)	0.0333 (6)
H25A	0.4782	0.0657	0.3968	0.040*
H25B	0.3633	0.0759	0.3228	0.040*
C26	0.2142 (2)	−0.1047 (3)	0.17900 (15)	0.0352 (7)
C27	0.2475 (3)	0.0131 (4)	0.12171 (16)	0.0458 (8)
H27A	0.2835	−0.0264	0.0717	0.069*
H27B	0.3075	0.0756	0.1545	0.069*
H27C	0.1736	0.0675	0.1013	0.069*
C28	0.1314 (3)	−0.2140 (4)	0.13137 (17)	0.0484 (8)
H28A	0.0541	−0.1691	0.1076	0.073*
H28B	0.1141	−0.2897	0.1717	0.073*
H28C	0.1723	−0.2544	0.0838	0.073*
C29	0.2868 (2)	0.3655 (3)	0.30546 (15)	0.0299 (6)
C30	0.1609 (2)	0.3732 (3)	0.30083 (16)	0.0380 (7)
H30	0.1208	0.3655	0.3520	0.046*
C31	0.0930 (3)	0.3923 (3)	0.22034 (17)	0.0423 (8)
H31	0.0058	0.3980	0.2168	0.051*
C32	0.1503 (3)	0.4034 (3)	0.14480 (17)	0.0363 (7)
C33	0.2781 (3)	0.3983 (3)	0.15257 (17)	0.0397 (7)
H33	0.3190	0.4075	0.1019	0.048*
C34	0.3470 (2)	0.3801 (3)	0.23193 (16)	0.0351 (7)
H34	0.4343	0.3776	0.2361	0.042*
C35	0.0762 (3)	0.4189 (4)	0.05773 (18)	0.0514 (8)
H35A	0.1229	0.3808	0.0125	0.077*
H35B	0.0584	0.5195	0.0462	0.077*
H35C	−0.0012	0.3665	0.0576	0.077*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0464 (4)	0.0303 (4)	0.0239 (3)	−0.0009 (3)	0.0023 (3)	−0.0021 (3)
O1	0.0468 (11)	0.0378 (13)	0.0338 (9)	−0.0049 (9)	0.0105 (8)	−0.0022 (8)
O2	0.0328 (10)	0.0770 (17)	0.0323 (9)	0.0110 (11)	0.0043 (8)	−0.0023 (10)
O3	0.0337 (10)	0.0388 (13)	0.0325 (8)	0.0022 (9)	0.0055 (7)	0.0022 (9)
O4	0.0467 (11)	0.0256 (11)	0.0260 (8)	0.0015 (9)	0.0046 (7)	−0.0009 (8)
O5	0.0482 (11)	0.0449 (14)	0.0326 (9)	−0.0158 (10)	−0.0064 (8)	0.0009 (9)
O6	0.0734 (14)	0.0392 (14)	0.0306 (9)	0.0083 (11)	0.0120 (9)	−0.0024 (9)
C1	0.0457 (16)	0.0346 (19)	0.0308 (13)	−0.0058 (13)	0.0107 (11)	0.0011 (12)
C2	0.0454 (16)	0.0284 (17)	0.0363 (14)	0.0088 (14)	0.0040 (12)	0.0046 (12)
C3	0.0431 (16)	0.035 (2)	0.0391 (14)	0.0106 (13)	−0.0041 (12)	0.0048 (14)
C4	0.0370 (16)	0.0387 (19)	0.0274 (12)	0.0031 (13)	−0.0039 (10)	0.0014 (12)
C5	0.0353 (15)	0.0362 (19)	0.0323 (13)	0.0046 (12)	0.0059 (11)	−0.0011 (12)
C6	0.0322 (14)	0.0336 (18)	0.0289 (12)	−0.0010 (13)	0.0024 (10)	−0.0034 (12)
C7	0.0558 (19)	0.0331 (18)	0.0430 (15)	−0.0011 (15)	−0.0107 (13)	−0.0017 (14)
C8	0.058 (2)	0.038 (2)	0.0438 (15)	−0.0073 (15)	−0.0057 (14)	−0.0009 (14)
C9	0.0312 (13)	0.0279 (16)	0.0266 (11)	0.0024 (12)	0.0031 (10)	0.0003 (12)
C10	0.0319 (14)	0.038 (2)	0.0336 (13)	−0.0029 (12)	0.0112 (11)	0.0061 (12)
C11	0.0233 (13)	0.0341 (19)	0.0465 (15)	−0.0006 (12)	0.0040 (11)	0.0063 (13)
C12	0.0344 (14)	0.0265 (17)	0.0319 (12)	−0.0018 (12)	−0.0028 (11)	−0.0013 (12)
C13	0.0310 (13)	0.0318 (17)	0.0291 (12)	−0.0029 (12)	0.0061 (10)	−0.0002 (12)
C14	0.0250 (13)	0.0357 (17)	0.0273 (11)	−0.0042 (12)	0.0035 (10)	−0.0028 (12)
C15	0.0442 (17)	0.053 (2)	0.0378 (14)	0.0004 (15)	−0.0052 (12)	0.0010 (15)
S2	0.0354 (4)	0.0359 (4)	0.0286 (3)	0.0021 (3)	0.0008 (3)	−0.0048 (3)
O11	0.0358 (10)	0.0478 (14)	0.0283 (9)	0.0019 (9)	0.0081 (7)	−0.0012 (9)
O12	0.0372 (10)	0.0429 (13)	0.0289 (9)	0.0126 (9)	0.0035 (7)	−0.0006 (8)
O13	0.0364 (10)	0.0445 (13)	0.0307 (9)	0.0112 (9)	0.0084 (7)	0.0056 (9)
O14	0.0402 (10)	0.0365 (13)	0.0288 (9)	0.0065 (9)	0.0056 (7)	−0.0015 (8)
O15	0.0312 (10)	0.0436 (13)	0.0390 (10)	−0.0023 (9)	−0.0008 (8)	−0.0065 (9)
O16	0.0512 (12)	0.0435 (14)	0.0352 (10)	0.0072 (10)	0.0049 (8)	−0.0097 (9)
C21	0.0406 (16)	0.0427 (19)	0.0290 (13)	−0.0028 (14)	0.0051 (11)	−0.0005 (13)
C22	0.0446 (17)	0.0300 (17)	0.0331 (13)	0.0048 (13)	0.0084 (11)	0.0057 (12)
C23	0.0458 (17)	0.037 (2)	0.0356 (14)	0.0102 (14)	0.0035 (12)	0.0081 (13)
C24	0.0302 (14)	0.0377 (19)	0.0297 (13)	0.0072 (12)	−0.0002 (10)	0.0043 (12)
C25	0.0329 (14)	0.0381 (18)	0.0290 (13)	0.0079 (13)	0.0037 (10)	−0.0046 (12)
C26	0.0366 (15)	0.0432 (19)	0.0261 (13)	0.0090 (13)	0.0047 (11)	−0.0014 (12)
C27	0.0513 (18)	0.051 (2)	0.0343 (14)	0.0006 (15)	0.0020 (12)	0.0087 (14)
C28	0.0561 (19)	0.055 (2)	0.0329 (14)	−0.0021 (16)	0.0018 (13)	−0.0016 (15)
C29	0.0343 (14)	0.0232 (17)	0.0316 (12)	0.0012 (12)	0.0008 (11)	−0.0029 (11)
C30	0.0312 (15)	0.048 (2)	0.0356 (14)	−0.0004 (13)	0.0085 (11)	0.0047 (13)
C31	0.0286 (15)	0.054 (2)	0.0440 (16)	0.0002 (14)	0.0036 (12)	0.0079 (14)
C32	0.0405 (15)	0.0320 (18)	0.0355 (14)	0.0001 (13)	0.0002 (12)	−0.0003 (12)
C33	0.0420 (17)	0.046 (2)	0.0324 (14)	0.0016 (14)	0.0098 (12)	−0.0005 (13)
C34	0.0275 (14)	0.042 (2)	0.0368 (14)	−0.0018 (12)	0.0059 (11)	−0.0005 (12)
C35	0.055 (2)	0.055 (2)	0.0416 (16)	−0.0039 (17)	−0.0059 (13)	−0.0018 (15)

Geometric parameters (Å, º) top

S1—O6	1.4167 (18)	S2—O16	1.4201 (18)
S1—O5	1.4332 (19)	S2—O15	1.4257 (17)
S1—O4	1.5740 (19)	S2—O14	1.578 (2)
S1—C9	1.758 (2)	S2—C29	1.760 (2)
O1—C1	1.410 (3)	O11—C21	1.402 (3)
O1—C4	1.439 (3)	O11—C24	1.445 (3)
O2—C1	1.413 (3)	O12—C21	1.421 (3)
O2—C6	1.431 (3)	O12—C26	1.427 (3)
O3—C2	1.426 (3)	O13—C22	1.426 (3)
O3—C6	1.432 (3)	O13—C26	1.436 (3)
O4—C5	1.467 (3)	O14—C25	1.464 (3)
C1—C2	1.535 (3)	C21—C22	1.544 (4)
C1—H1	1.0000	C21—H21	1.0000
C2—C3	1.510 (4)	C22—C23	1.516 (4)
C2—H2	1.0000	C22—H22	1.0000
C3—C4	1.522 (4)	C23—C24	1.526 (4)
C3—H3A	0.9900	C23—H23A	0.9900
C3—H3B	0.9900	C23—H23B	0.9900
C4—C5	1.503 (4)	C24—C25	1.501 (4)
C4—H4	1.0000	C24—H24	1.0000
C5—H5A	0.9900	C25—H25A	0.9900
C5—H5B	0.9900	C25—H25B	0.9900
C6—C7	1.502 (4)	C26—C27	1.492 (4)
C6—C8	1.508 (4)	C26—C28	1.509 (4)
C7—H7A	0.9800	C27—H27A	0.9800
C7—H7B	0.9800	C27—H27B	0.9800
C7—H7C	0.9800	C27—H27C	0.9800
C8—H8A	0.9800	C28—H28A	0.9800
C8—H8B	0.9800	C28—H28B	0.9800
C8—H8C	0.9800	C28—H28C	0.9800
C9—C14	1.383 (3)	C29—C30	1.372 (3)
C9—C10	1.390 (3)	C29—C34	1.385 (3)
C10—C11	1.373 (3)	C30—C31	1.390 (4)
C10—H10	0.9500	C30—H30	0.9500
C11—C12	1.385 (3)	C31—C32	1.392 (3)
C11—H11	0.9500	C31—H31	0.9500
C12—C13	1.384 (3)	C32—C33	1.391 (4)
C12—C15	1.514 (3)	C32—C35	1.501 (4)
C13—C14	1.380 (3)	C33—C34	1.378 (4)
C13—H13	0.9500	C33—H33	0.9500
C14—H14	0.9500	C34—H34	0.9500
C15—H15A	0.9800	C35—H35A	0.9800
C15—H15B	0.9800	C35—H35B	0.9800
C15—H15C	0.9800	C35—H35C	0.9800

O6—S1—O5	119.90 (13)	O16—S2—O15	119.98 (12)
O6—S1—O4	104.30 (11)	O16—S2—O14	104.35 (11)
O5—S1—O4	109.14 (11)	O15—S2—O14	108.99 (11)
O6—S1—C9	109.36 (12)	O16—S2—C29	109.76 (12)
O5—S1—C9	108.18 (11)	O15—S2—C29	108.69 (11)
O4—S1—C9	104.94 (11)	O14—S2—C29	103.82 (11)
C1—O1—C4	110.36 (19)	C21—O11—C24	109.26 (19)
C1—O2—C6	109.11 (18)	C21—O12—C26	106.85 (19)
C2—O3—C6	106.69 (18)	C22—O13—C26	106.29 (18)
C5—O4—S1	117.38 (15)	C25—O14—S2	117.15 (15)
O1—C1—O2	111.1 (2)	O11—C21—O12	110.5 (2)
O1—C1—C2	107.7 (2)	O11—C21—C22	108.0 (2)
O2—C1—C2	105.09 (18)	O12—C21—C22	104.04 (18)
O1—C1—H1	110.9	O11—C21—H21	111.3
O2—C1—H1	110.9	O12—C21—H21	111.3
C2—C1—H1	110.9	C22—C21—H21	111.3
O3—C2—C3	110.5 (2)	O13—C22—C23	112.1 (2)
O3—C2—C1	103.4 (2)	O13—C22—C21	104.2 (2)
C3—C2—C1	104.0 (2)	C23—C22—C21	104.2 (2)
O3—C2—H2	112.7	O13—C22—H22	112.0
C3—C2—H2	112.7	C23—C22—H22	112.0
C1—C2—H2	112.7	C21—C22—H22	112.0
C2—C3—C4	104.0 (2)	C22—C23—C24	104.4 (2)
C2—C3—H3A	110.9	C22—C23—H23A	110.9
C4—C3—H3A	110.9	C24—C23—H23A	110.9
C2—C3—H3B	110.9	C22—C23—H23B	110.9
C4—C3—H3B	110.9	C24—C23—H23B	110.9
H3A—C3—H3B	109.0	H23A—C23—H23B	108.9
O1—C4—C5	111.8 (2)	O11—C24—C25	112.3 (2)
O1—C4—C3	104.8 (2)	O11—C24—C23	104.6 (2)
C5—C4—C3	112.4 (2)	C25—C24—C23	112.8 (2)
O1—C4—H4	109.2	O11—C24—H24	109.0
C5—C4—H4	109.2	C25—C24—H24	109.0
C3—C4—H4	109.2	C23—C24—H24	109.0
O4—C5—C4	106.98 (19)	O14—C25—C24	107.61 (19)
O4—C5—H5A	110.3	O14—C25—H25A	110.2
C4—C5—H5A	110.3	C24—C25—H25A	110.2
O4—C5—H5B	110.3	O14—C25—H25B	110.2
C4—C5—H5B	110.3	C24—C25—H25B	110.2
H5A—C5—H5B	108.6	H25A—C25—H25B	108.5
O3—C6—O2	104.07 (17)	O12—C26—O13	102.86 (18)
O3—C6—C7	108.8 (2)	O12—C26—C27	109.8 (2)
O2—C6—C7	109.2 (2)	O13—C26—C27	109.4 (2)
O3—C6—C8	111.6 (2)	O12—C26—C28	110.0 (2)
O2—C6—C8	110.1 (2)	O13—C26—C28	111.3 (3)
C7—C6—C8	112.7 (2)	C27—C26—C28	113.0 (2)
C6—C7—H7A	109.5	C26—C27—H27A	109.5
C6—C7—H7B	109.5	C26—C27—H27B	109.5
H7A—C7—H7B	109.5	H27A—C27—H27B	109.5
C6—C7—H7C	109.5	C26—C27—H27C	109.5
H7A—C7—H7C	109.5	H27A—C27—H27C	109.5
H7B—C7—H7C	109.5	H27B—C27—H27C	109.5
C6—C8—H8A	109.5	C26—C28—H28A	109.5
C6—C8—H8B	109.5	C26—C28—H28B	109.5
H8A—C8—H8B	109.5	H28A—C28—H28B	109.5
C6—C8—H8C	109.5	C26—C28—H28C	109.5
H8A—C8—H8C	109.5	H28A—C28—H28C	109.5
H8B—C8—H8C	109.5	H28B—C28—H28C	109.5
C14—C9—C10	120.2 (2)	C30—C29—C34	121.2 (2)
C14—C9—S1	119.69 (18)	C30—C29—S2	119.01 (19)
C10—C9—S1	120.11 (18)	C34—C29—S2	119.74 (19)
C11—C10—C9	119.1 (2)	C29—C30—C31	119.1 (2)
C11—C10—H10	120.5	C29—C30—H30	120.4
C9—C10—H10	120.5	C31—C30—H30	120.4
C10—C11—C12	121.7 (2)	C30—C31—C32	121.1 (2)
C10—C11—H11	119.2	C30—C31—H31	119.4
C12—C11—H11	119.2	C32—C31—H31	119.4
C13—C12—C11	118.4 (2)	C33—C32—C31	117.9 (2)
C13—C12—C15	120.9 (2)	C33—C32—C35	121.2 (2)
C11—C12—C15	120.7 (2)	C31—C32—C35	120.9 (3)
C14—C13—C12	120.9 (2)	C34—C33—C32	121.7 (2)
C14—C13—H13	119.6	C34—C33—H33	119.1
C12—C13—H13	119.6	C32—C33—H33	119.1
C13—C14—C9	119.7 (2)	C33—C34—C29	118.8 (2)
C13—C14—H14	120.2	C33—C34—H34	120.6
C9—C14—H14	120.2	C29—C34—H34	120.6
C12—C15—H15A	109.5	C32—C35—H35A	109.5
C12—C15—H15B	109.5	C32—C35—H35B	109.5
H15A—C15—H15B	109.5	H35A—C35—H35B	109.5
C12—C15—H15C	109.5	C32—C35—H35C	109.5
H15A—C15—H15C	109.5	H35A—C35—H35C	109.5
H15B—C15—H15C	109.5	H35B—C35—H35C	109.5

O6—S1—O4—C5	−179.34 (17)	O16—S2—O14—C25	−171.83 (16)
O5—S1—O4—C5	−50.06 (19)	O15—S2—O14—C25	−42.51 (17)
C9—S1—O4—C5	65.69 (18)	C29—S2—O14—C25	73.20 (17)
C4—O1—C1—O2	−105.4 (2)	C24—O11—C21—O12	−94.0 (2)
C4—O1—C1—C2	9.2 (3)	C24—O11—C21—C22	19.2 (3)
C6—O2—C1—O1	124.0 (2)	C26—O12—C21—O11	139.4 (2)
C6—O2—C1—C2	7.8 (3)	C26—O12—C21—C22	23.7 (3)
C6—O3—C2—C3	−140.6 (2)	C26—O13—C22—C23	−135.6 (2)
C6—O3—C2—C1	−29.8 (3)	C26—O13—C22—C21	−23.6 (3)
O1—C1—C2—O3	−105.1 (2)	O11—C21—C22—O13	−117.4 (2)
O2—C1—C2—O3	13.4 (3)	O12—C21—C22—O13	0.1 (3)
O1—C1—C2—C3	10.4 (3)	O11—C21—C22—C23	0.2 (3)
O2—C1—C2—C3	128.9 (2)	O12—C21—C22—C23	117.7 (2)
O3—C2—C3—C4	85.9 (2)	O13—C22—C23—C24	94.0 (2)
C1—C2—C3—C4	−24.6 (3)	C21—C22—C23—C24	−18.0 (3)
C1—O1—C4—C5	97.1 (2)	C21—O11—C24—C25	92.0 (3)
C1—O1—C4—C3	−24.9 (2)	C21—O11—C24—C23	−30.7 (3)
C2—C3—C4—O1	30.4 (3)	C22—C23—C24—O11	29.6 (3)
C2—C3—C4—C5	−91.2 (3)	C22—C23—C24—C25	−92.8 (3)
S1—O4—C5—C4	178.03 (15)	S2—O14—C25—C24	−177.50 (16)
O1—C4—C5—O4	62.0 (3)	O11—C24—C25—O14	63.8 (2)
C3—C4—C5—O4	179.55 (19)	C23—C24—C25—O14	−178.25 (19)
C2—O3—C6—O2	35.0 (3)	C21—O12—C26—O13	−38.7 (3)
C2—O3—C6—C7	151.4 (2)	C21—O12—C26—C27	−155.1 (2)
C2—O3—C6—C8	−83.7 (3)	C21—O12—C26—C28	79.9 (3)
C1—O2—C6—O3	−26.1 (3)	C22—O13—C26—O12	38.6 (3)
C1—O2—C6—C7	−142.1 (2)	C22—O13—C26—C27	155.2 (2)
C1—O2—C6—C8	93.7 (3)	C22—O13—C26—C28	−79.2 (2)
O6—S1—C9—C14	138.3 (2)	O16—S2—C29—C30	−43.9 (3)
O5—S1—C9—C14	6.1 (3)	O15—S2—C29—C30	−176.9 (2)
O4—S1—C9—C14	−110.3 (2)	O14—S2—C29—C30	67.2 (2)
O6—S1—C9—C10	−41.2 (3)	O16—S2—C29—C34	135.5 (2)
O5—S1—C9—C10	−173.4 (2)	O15—S2—C29—C34	2.5 (3)
O4—S1—C9—C10	70.2 (2)	O14—S2—C29—C34	−113.4 (2)
C14—C9—C10—C11	−1.4 (4)	C34—C29—C30—C31	1.7 (4)
S1—C9—C10—C11	178.1 (2)	S2—C29—C30—C31	−178.9 (2)
C9—C10—C11—C12	0.1 (4)	C29—C30—C31—C32	0.2 (5)
C10—C11—C12—C13	1.0 (4)	C30—C31—C32—C33	−1.6 (5)
C10—C11—C12—C15	−179.3 (3)	C30—C31—C32—C35	177.8 (3)
C11—C12—C13—C14	−0.8 (4)	C31—C32—C33—C34	1.2 (5)
C15—C12—C13—C14	179.5 (3)	C35—C32—C33—C34	−178.1 (3)
C12—C13—C14—C9	−0.4 (4)	C32—C33—C34—C29	0.5 (4)
C10—C9—C14—C13	1.6 (4)	C30—C29—C34—C33	−2.0 (4)
S1—C9—C14—C13	−177.9 (2)	S2—C29—C34—C33	178.6 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O5ⁱ	1.00	2.48	3.390 (3)	152
C5—H5B···O3	0.99	2.56	3.196 (3)	122
C11—H11···O12ⁱⁱ	0.95	2.44	3.163 (3)	133
C14—H14···O5	0.95	2.51	2.897 (3)	105
C24—H24···O15ⁱⁱⁱ	1.00	2.42	3.315 (3)	148
C28—H28C···O6^iv	0.98	2.54	3.471 (3)	159
C34—H34···O15	0.95	2.53	2.908 (3)	104

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

Experimental details

Crystal data
Chemical formula	C₁₅H₂₀O₆S
M_r	328.37
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	123
a, b, c (Å)	10.9397 (1), 9.4251 (1), 15.4833 (10)
β (°)	96.414 (7)
V (Å³)	1586.46 (10)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	2.06
Crystal size (mm)	0.2 × 0.2 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPID II imaging plate
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.55, 0.65
No. of measured, independent and observed [I > 2σ(I)] reflections	14179, 4917, 4440
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.590

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.087, 1.04
No. of reflections	4917
No. of parameters	404
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.26
Absolute structure	Flack (1983), 2059 Friedel pairs
Absolute structure parameter	0.005 (12)

Computer programs: CrystalClear-SM Expert (Rigaku, 2009), HKL-2000 (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1999) and Mercury (Macrae et al., 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O5ⁱ	1.00	2.48	3.390 (3)	152
C5—H5B···O3	0.99	2.56	3.196 (3)	122
C11—H11···O12ⁱⁱ	0.95	2.44	3.163 (3)	133
C24—H24···O15ⁱⁱⁱ	1.00	2.42	3.315 (3)	148
C28—H28C···O6^iv	0.98	2.54	3.471 (3)	159

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

Acknowledgements

This study was supported by the NSF (grant CHE-0922366 for X-ray diffractometer) and by SUNY (grant No 1073053).

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