A chiral 3,4-di­hydro-2H-thio­pyran compound

Evain, M.; Collet, S.; Guingant, A.

doi:10.1107/S1600536802016689

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A chiral 3,4-dihydro-2H-thiopyran compound

M. Evain, S. Collet and A. Guingant

The title compound, dimethyl (3R,4S)-3-{[(4S)-4-benzyl-2-oxo-1,3-oxazolidin-3-yl]carbonyl}-4-dimethylamino-3,4-dihydro-2H-thiopyran-5,6-dicarboxylate, C₂₂H₂₆N₂O₇S, is the result of a diastereoselective Diels-Alder reaction between dimethyl (2E)-[(dimethylamino)methylene]-3-thiosuccinate and (4S)-3-acryloyl-4-benzyl-1,3-oxazolidin-2-one used as chiral auxiliary. Following an X-ray structure determination, the absolute configurations of both stereogenic centres formed during the cycloaddition were determined.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536802016689/dn6039sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536802016689/dn6039Isup2.hkl Contains datablock I

CCDC reference: 198965

checkCIF report

Key indicators

Single-crystal X-ray study
T = 150 K
Mean (C-C) = 0.003 Å
R factor = 0.043
wR factor = 0.088
Data-to-parameter ratio = 16.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           26.73
         From the CIF: _reflns_number_total               4753
         Count of symmetry unique reflns         2776
         Completeness (_total/calc)            171.22%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured      1977
         Fraction of Friedel pairs measured     0.712
         Are heavy atom types Z>Si present          yes
          Please check that the estimate of the number of Friedel pairs is
          correct. If it is not, please give the correct count in the
          _publ_section_exptl_refinement section of the submitted CIF.

Comment top

Asymmetric hetero Diels-Alder reaction appears to be the method of choice for the highly efficient regio- and stereoselective synthesis of various heterocycles in enantiomerically pure form (Waldmann, 1994). In the course of an ongoing project (Trippé et al., 2002) and regarding previous results obtained in our laboratory (Marchand et al., 1995), we have isolated the substituted dihydro-2H-thiopyran resulting from the [4 + 2] cycloaddition reaction of dimethyl (2E)-[(dimethylamino)methylene]-3-thiosuccinate (Tea Gokou et al., 1985) and (4S)-3-acryloyl-4-benzyl-1,3-oxazolidin-2-one (Evans et al., 1984) in the presence of MgBr₂ as catalyst. Only two diastereoisomers, in a 7/3 ratio, were obtained at the end of the reaction and separated by chromatography on SiO₂. The major component is the title compound, (I), and is the result of an exo transition-state topography in the cycloaddition transition state, whereas the minor component is presumed to come from an endo approach. A full report on the synthesis as well as structural and mechanistic studies will be reported separately. Atoms O5, C12, N2, C13 and O6 are planar within less than 0.09 Å.

Experimental top

To a suspension of activated magnesium turnings (3.25 mmol) in dry Et₂O was added 1,2-dibromoethane (3.25 mmol). The resulting mixture was stirred until all magnesium turnings disappeared, and the solvent was evaporated under an N₂ draught. After addition of dry CH₂Cl₂ (10 ml), (4S)-3-acryloyl-4-benzyl-1,3-oxazolidin-2-one (1.10 mmol) in anhydrous CH₂Cl₂ (3 ml) was added at 263 K. After stirring at 263 K for 15 min, dimethyl (2E)-[(dimethylamino)methylene]-3-thiosuccinate (1.10 mmol) was slowly added. The reaction mixture was then stirred at 263 K for 3 h. Saturated NaHCO₃ (5 ml) was added and the organic layer was washed with saturated NaHCO₃ (2 x 5 ml), water (5 ml) and brine (5 ml). The CH₂Cl₂ extract was then dried over anhydrous MgSO₄, filtered and concentrated. The crude mixture was flash-chromatographed on silica (eluent: petroleum ether/AcOEt, 7:3) to afford (I) (285 mg, 57%) along with one other diastereoisomer (142 mg, 28%). Single crystals of (I) suitable for X-ray analysis were obtained by crystallization from AcOEt/petroleum ether.

Computing details top

Data collection: Collect (Nonius, 1998); cell refinement: HKL SCALEPACK; data reduction: HKL DENZO and SCALEPACK (Otwinowski & Minor 1997); program(s) used to solve structure: SHELXTL (Sheldrick, 1995); program(s) used to refine structure: JANA2000 (Petricek & Dusek, 2000); molecular graphics: DIAMOND (Brandenburg & Berndt, 1999); software used to prepare material for publication: JANA2000.

Figures top

Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids. H are omitted for clarity.

(I) top

Crystal data top

C₂₂H₂₆N₂O₇S	F(000) = 976
M_r = 462.5	D_x = 1.358 (1) Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: P 2ac 2ab	Cell parameters from 14696 reflections
a = 6.1205 (1) Å	θ = 2.9–26.7°
b = 16.1195 (4) Å	µ = 0.19 mm⁻¹
c = 22.9272 (6) Å	T = 150 K
V = 2261.98 (9) Å³	Needle, colourless
Z = 4	0.4 × 0.03 × 0.03 mm

Data collection top

Nonius KappaCCD diffractometer	3833 reflections with I > 2σ(I)
Horizonally mounted graphite crystal monochromator	R_int = 0.063
Detector resolution: 9 pixels mm^-1	θ_max = 26.7°, θ_min = 3.0°
ϕ and ω scans	h = −7→6
22365 measured reflections	k = −20→20
4753 independent reflections	l = −28→28

Refinement top

Refinement on F²	(Δ/σ)_max = 0.0003
R[F² > 2σ(F²)] = 0.043	Δρ_max = 0.76 e Å⁻³
wR(F²) = 0.088	Δρ_min = −0.40 e Å⁻³
S = 1.23	Extinction correction: B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)
4753 reflections	Extinction coefficient: 1.5 (2)
290 parameters	Absolute structure: Flack (1983)
H-atom parameters not refined	Absolute structure parameter: 0.00 (8)
Weighting scheme based on measured s.u.'s w = 1/[σ²(I) + 0.001296I²]

Crystal data top

C₂₂H₂₆N₂O₇S	V = 2261.98 (9) Å³
M_r = 462.5	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.1205 (1) Å	µ = 0.19 mm⁻¹
b = 16.1195 (4) Å	T = 150 K
c = 22.9272 (6) Å	0.4 × 0.03 × 0.03 mm

Data collection top

Nonius KappaCCD diffractometer	3833 reflections with I > 2σ(I)
22365 measured reflections	R_int = 0.063
4753 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	H-atom parameters not refined
wR(F²) = 0.088	Δρ_max = 0.76 e Å⁻³
S = 1.23	Δρ_min = −0.40 e Å⁻³
4753 reflections	Absolute structure: Flack (1983)
290 parameters	Absolute structure parameter: 0.00 (8)

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

	x	y	z	U_iso*/U_eq
S1	0.65977 (10)	0.24954 (4)	0.58687 (2)	0.03101 (18)
O1	1.0275 (2)	0.24942 (11)	0.67157 (7)	0.0330 (5)
O2	0.7764 (3)	0.24146 (11)	0.74256 (7)	0.0419 (6)
O3	0.4552 (3)	0.42098 (11)	0.75962 (7)	0.0416 (6)
O4	0.8120 (3)	0.42069 (10)	0.73764 (7)	0.0346 (5)
O5	0.0474 (3)	0.43346 (11)	0.55260 (7)	0.0331 (5)
O6	0.5974 (2)	0.39058 (10)	0.44840 (7)	0.0288 (5)
O7	0.3752 (2)	0.44087 (9)	0.38016 (6)	0.0300 (5)
N1	0.4240 (3)	0.51056 (10)	0.62651 (8)	0.0266 (6)
N2	0.2516 (3)	0.44179 (10)	0.47143 (7)	0.0211 (5)
C1	0.6838 (4)	0.30598 (13)	0.65181 (9)	0.0232 (6)
C2	0.5706 (3)	0.37440 (13)	0.66589 (9)	0.0215 (6)
C3	0.4053 (3)	0.41930 (12)	0.62726 (9)	0.0221 (6)
C4	0.4179 (3)	0.38923 (12)	0.56409 (9)	0.0211 (6)
C5	0.4115 (4)	0.29436 (13)	0.55889 (9)	0.0268 (7)
C6	0.8311 (4)	0.26296 (13)	0.69466 (10)	0.0259 (7)
C7	1.1805 (4)	0.20477 (17)	0.70814 (12)	0.0442 (9)
C8	0.6004 (4)	0.40785 (13)	0.72597 (10)	0.0264 (7)
C9	0.8661 (5)	0.44372 (18)	0.79658 (12)	0.0503 (10)
C10	0.6446 (4)	0.54365 (13)	0.62428 (11)	0.0357 (8)
C11	0.2850 (4)	0.55502 (15)	0.66718 (12)	0.0397 (8)
C12	0.2254 (4)	0.42336 (13)	0.53065 (9)	0.0222 (6)
C13	0.4264 (4)	0.42150 (13)	0.43551 (9)	0.0230 (7)
C14	0.1481 (4)	0.46520 (13)	0.37559 (10)	0.0296 (7)
C15	0.0686 (4)	0.47803 (13)	0.43826 (9)	0.0264 (7)
C16	0.0247 (4)	0.56882 (15)	0.45392 (10)	0.0311 (8)
C17	0.2129 (4)	0.62708 (13)	0.44358 (10)	0.0293 (7)
C18	0.3805 (4)	0.63447 (13)	0.48435 (10)	0.0293 (7)
C19	0.5533 (4)	0.68855 (14)	0.47556 (11)	0.0344 (8)
C20	0.5623 (5)	0.73578 (14)	0.42505 (11)	0.0397 (8)
C21	0.3983 (5)	0.72937 (14)	0.38425 (11)	0.0426 (9)
C22	0.2249 (4)	0.67556 (14)	0.39350 (10)	0.0344 (8)
H3	0.2637	0.4078	0.6454	0.026*
H4	0.5569	0.4089	0.5479	0.025*
H5a	0.3896	0.2828	0.5174	0.032*
H5b	0.282	0.2769	0.5809	0.032*
H7a	1.2327	0.2403	0.7395	0.053*
H7b	1.1156	0.1552	0.7246	0.053*
H7c	1.3022	0.1896	0.6832	0.053*
H9a	1.0225	0.4526	0.7973	0.06*
H9b	0.7913	0.4947	0.8067	0.06*
H9c	0.8277	0.4007	0.8245	0.06*
H10a	0.7382	0.5107	0.5992	0.043*
H10b	0.6362	0.5999	0.6094	0.053*
H10c	0.7047	0.5446	0.6635	0.043*
H11a	0.2753	0.612	0.6539	0.048*
H11b	0.3407	0.5538	0.7068	0.048*
H11c	0.141	0.5298	0.6662	0.048*
H14a	0.0659	0.421	0.356	0.035*
H14b	0.1376	0.5163	0.3528	0.035*
H15	−0.0717	0.4514	0.4471	0.032*
H16a	−0.0989	0.5885	0.4306	0.037*
H16b	−0.0128	0.5718	0.4955	0.037*
H18	0.3768	0.6008	0.5198	0.035*
H19	0.6686	0.6934	0.505	0.041*
H20	0.6848	0.7737	0.4182	0.048*
H21	0.4044	0.7631	0.3488	0.051*
H22	0.11	0.6717	0.364	0.041*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0457 (4)	0.0271 (3)	0.0203 (3)	0.0118 (3)	−0.0042 (3)	−0.0060 (2)
O1	0.0281 (8)	0.0411 (9)	0.0299 (8)	0.0105 (8)	0.0025 (7)	0.0078 (8)
O2	0.0407 (10)	0.0575 (11)	0.0275 (9)	0.0126 (9)	0.0058 (8)	0.0158 (8)
O3	0.0392 (10)	0.0620 (12)	0.0236 (9)	0.0157 (9)	−0.0013 (9)	−0.0138 (8)
O4	0.0324 (9)	0.0452 (10)	0.0261 (9)	−0.0015 (8)	−0.0076 (7)	−0.0094 (7)
O5	0.0240 (8)	0.0487 (10)	0.0265 (9)	0.0014 (8)	0.0031 (8)	0.0048 (8)
O6	0.0210 (8)	0.0401 (9)	0.0253 (9)	−0.0019 (7)	0.0014 (7)	−0.0011 (7)
O7	0.0318 (9)	0.0380 (9)	0.0202 (8)	−0.0039 (7)	−0.0005 (7)	0.0063 (7)
N1	0.0289 (10)	0.0202 (9)	0.0308 (11)	0.0034 (8)	−0.0009 (9)	−0.0036 (8)
N2	0.0199 (9)	0.0239 (10)	0.0195 (9)	−0.0017 (8)	−0.0014 (8)	0.0020 (7)
C1	0.0259 (11)	0.0259 (11)	0.0178 (11)	−0.0005 (10)	0.0030 (10)	0.0000 (9)
C2	0.0225 (11)	0.0244 (11)	0.0176 (11)	0.0001 (9)	0.0011 (10)	−0.0006 (9)
C3	0.0234 (11)	0.0215 (11)	0.0214 (11)	0.0004 (9)	0.0013 (10)	−0.0001 (9)
C4	0.0198 (10)	0.0225 (11)	0.0209 (11)	−0.0006 (9)	−0.0005 (9)	0.0023 (9)
C5	0.0376 (13)	0.0263 (11)	0.0166 (11)	−0.0006 (10)	−0.0041 (11)	−0.0015 (9)
C6	0.0311 (12)	0.0201 (11)	0.0265 (12)	0.0014 (10)	−0.0032 (10)	−0.0010 (9)
C7	0.0340 (14)	0.0545 (16)	0.0441 (16)	0.0144 (13)	0.0005 (13)	0.0111 (13)
C8	0.0302 (13)	0.0293 (12)	0.0196 (12)	0.0054 (10)	−0.0016 (11)	−0.0014 (9)
C9	0.0493 (17)	0.0656 (19)	0.0362 (15)	0.0046 (15)	−0.0146 (14)	−0.0199 (13)
C10	0.0360 (13)	0.0279 (12)	0.0432 (15)	−0.0036 (11)	−0.0017 (12)	0.0007 (11)
C11	0.0447 (15)	0.0319 (13)	0.0427 (15)	0.0108 (12)	−0.0018 (13)	−0.0093 (11)
C12	0.0224 (12)	0.0225 (11)	0.0218 (11)	−0.0027 (9)	0.0003 (10)	−0.0006 (9)
C13	0.0250 (12)	0.0223 (11)	0.0218 (12)	−0.0079 (10)	−0.0001 (10)	0.0000 (9)
C14	0.0351 (13)	0.0259 (11)	0.0277 (13)	−0.0040 (10)	−0.0101 (11)	0.0032 (9)
C15	0.0201 (11)	0.0337 (12)	0.0256 (12)	−0.0027 (10)	−0.0052 (10)	0.0070 (10)
C16	0.0250 (12)	0.0364 (13)	0.0320 (14)	0.0082 (11)	−0.0017 (10)	0.0044 (11)
C17	0.0330 (13)	0.0253 (11)	0.0297 (13)	0.0085 (10)	0.0030 (11)	−0.0044 (10)
C18	0.0384 (14)	0.0195 (11)	0.0299 (13)	0.0072 (10)	−0.0007 (11)	−0.0022 (9)
C19	0.0401 (13)	0.0237 (12)	0.0395 (15)	0.0036 (11)	−0.0059 (12)	−0.0082 (11)
C20	0.0483 (15)	0.0288 (13)	0.0421 (15)	−0.0048 (12)	0.0075 (13)	−0.0054 (11)
C21	0.0641 (18)	0.0308 (13)	0.0330 (14)	−0.0044 (13)	0.0044 (14)	0.0049 (10)
C22	0.0478 (15)	0.0269 (12)	0.0286 (13)	0.0028 (11)	−0.0075 (12)	0.0002 (10)

Geometric parameters (Å, º) top

S1—C1	1.751 (2)	C7—H7b	0.969
S1—C5	1.801 (2)	C7—H7c	0.970
O1—C6	1.332 (3)	C9—H9a	0.968
O1—C7	1.449 (3)	C9—H9b	0.969
O2—C6	1.199 (3)	C9—H9c	0.973
O3—C8	1.196 (3)	C10—H10a	0.970
O4—C8	1.339 (3)	C10—H10b	0.970
O4—C9	1.440 (3)	C10—H10c	0.971
O5—C12	1.211 (3)	C11—H11a	0.969
O6—C13	1.196 (3)	C11—H11b	0.970
O7—C13	1.344 (3)	C11—H11c	0.971
O7—C14	1.448 (3)	C14—C15	1.531 (3)
N1—C3	1.476 (3)	C14—H14a	0.981
N1—C10	1.453 (3)	C14—H14b	0.978
N1—C11	1.452 (3)	C15—C16	1.531 (3)
N2—C12	1.399 (3)	C15—H15	0.981
N2—C13	1.389 (3)	C16—C17	1.505 (3)
N2—C15	1.474 (3)	C16—H16a	0.979
C1—C2	1.342 (3)	C16—H16b	0.981
C1—C6	1.503 (3)	C17—C18	1.393 (3)
C2—C3	1.527 (3)	C17—C22	1.391 (3)
C2—C8	1.490 (3)	C18—C19	1.385 (3)
C3—C4	1.529 (3)	C18—H18	0.977
C3—H3	0.979	C19—C20	1.387 (4)
C4—C5	1.534 (3)	C19—H19	0.980
C4—C12	1.510 (3)	C20—C21	1.376 (4)
C4—H4	0.981	C20—H20	0.980
C5—H5a	0.979	C21—C22	1.387 (4)
C5—H5b	0.981	C21—H21	0.979
C7—H7a	0.972	C22—H22	0.978

C1—S1—C5	99.52 (10)	N1—C10—H10b	107.8
C6—O1—C7	115.78 (18)	N1—C10—H10c	109.0
C8—O4—C9	116.72 (18)	H10a—C10—H10b	109.5
C13—O7—C14	110.81 (17)	H10a—C10—H10c	109.5
C3—N1—C10	116.00 (17)	H10b—C10—H10c	109.4
C3—N1—C11	116.06 (17)	N1—C11—H11a	107.6
C10—N1—C11	112.71 (18)	N1—C11—H11b	112.7
C12—N2—C13	127.85 (17)	N1—C11—H11c	108.0
C12—N2—C15	119.84 (17)	H11a—C11—H11b	109.6
C13—N2—C15	111.87 (17)	H11a—C11—H11c	109.5
S1—C1—C2	126.02 (17)	H11b—C11—H11c	109.4
S1—C1—C6	111.50 (15)	O5—C12—N2	118.55 (19)
C2—C1—C6	122.12 (19)	O5—C12—C4	122.69 (19)
C1—C2—C3	126.31 (19)	N2—C12—C4	118.73 (18)
C1—C2—C8	117.16 (19)	O6—C13—O7	122.3 (2)
C3—C2—C8	116.46 (18)	O6—C13—N2	128.7 (2)
N1—C3—C2	115.35 (17)	O7—C13—N2	108.99 (18)
N1—C3—C4	107.51 (16)	O7—C14—C15	105.89 (17)
N1—C3—H3	105.18	O7—C14—H14a	109.18
C2—C3—C4	111.46 (17)	O7—C14—H14b	109.3
C2—C3—H3	104.49	C15—C14—H14a	111.3
C4—C3—H3	112.80	C15—C14—H14b	111.50
C3—C4—C5	112.84 (17)	H14a—C14—H14b	109.5
C3—C4—C12	109.04 (17)	N2—C15—C14	100.89 (17)
C3—C4—H4	107.39	N2—C15—C16	113.02 (18)
C5—C4—C12	107.70 (17)	N2—C15—H15	112.66
C5—C4—H4	108.35	C14—C15—C16	113.90 (18)
C12—C4—H4	111.57	C14—C15—H15	114.4
S1—C5—C4	110.54 (15)	C16—C15—H15	102.50
S1—C5—H5a	112.69	C15—C16—C17	115.18 (19)
S1—C5—H5b	112.57	C15—C16—H16a	108.5
C4—C5—H5a	105.60	C15—C16—H16b	108.4
C4—C5—H5b	105.44	C17—C16—H16a	107.6
H5a—C5—H5b	109.5	C17—C16—H16b	107.5
O1—C6—O2	124.6 (2)	H16a—C16—H16b	109.4
O1—C6—C1	110.93 (18)	C16—C17—C18	120.7 (2)
O2—C6—C1	124.4 (2)	C16—C17—C22	121.4 (2)
O1—C7—H7a	110.4	C18—C17—C22	117.9 (2)
O1—C7—H7b	111.7	C17—C18—C19	121.2 (2)
O1—C7—H7c	106.3	C17—C18—H18	119.5
H7a—C7—H7b	109.4	C19—C18—H18	119.2
H7a—C7—H7c	109.3	C18—C19—C20	119.8 (2)
H7b—C7—H7c	109.6	C18—C19—H19	120.0
O3—C8—O4	124.3 (2)	C20—C19—H19	120.2
O3—C8—C2	124.7 (2)	C19—C20—C21	119.8 (2)
O4—C8—C2	111.02 (18)	C19—C20—H20	120.5
O4—C9—H9a	106.3	C21—C20—H20	119.7
O4—C9—H9b	109.6	C20—C21—C22	120.1 (2)
O4—C9—H9c	112.3	C20—C21—H21	119.7
H9a—C9—H9b	109.8	C22—C21—H21	120.2
H9a—C9—H9c	109.4	C17—C22—C21	121.2 (2)
H9b—C9—H9c	109.4	C17—C22—H22	119.8
N1—C10—H10a	111.7	C21—C22—H22	119.0

Experimental details

Crystal data
Chemical formula	C₂₂H₂₆N₂O₇S
M_r	462.5
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	150
a, b, c (Å)	6.1205 (1), 16.1195 (4), 22.9272 (6)
V (Å³)	2261.98 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.19
Crystal size (mm)	0.4 × 0.03 × 0.03

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	22365, 4753, 3833
R_int	0.063
(sin θ/λ)_max (Å⁻¹)	0.633

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.088, 1.23
No. of reflections	4753
No. of parameters	290
No. of restraints	?
H-atom treatment	H-atom parameters not refined
Δρ_max, Δρ_min (e Å⁻³)	0.76, −0.40
Absolute structure	Flack (1983)
Absolute structure parameter	0.00 (8)

Computer programs: Collect (Nonius, 1998), HKL SCALEPACK, HKL DENZO and SCALEPACK (Otwinowski & Minor 1997), SHELXTL (Sheldrick, 1995), JANA2000 (Petricek & Dusek, 2000), DIAMOND (Brandenburg & Berndt, 1999), JANA2000.

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