organic compounds
6-Azido-3-O-benzyl-6-deoxy-N,N-diethyl-1,2-O-isopropylidene-D-glycero-α-D-gluco-heptofuranuronamide
aDepartment of Organic Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, England, bDpto. Química Orgánica, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain, and cDepartment of Chemical Crystallography, Chemistry Research, Laboratory, University of Oxford, Oxford OX1 3TA, England
*Correspondence e-mail: sarah.jenkinson@chem.ox.ac.uk
Reaction of 3-O-benzyl-1,2-O-isopropylidene-α-xylo-pentodialdo-1,4-furanose with N,N-diethyl-2-(dimethylsulfuranilidene)acetamide gave stereoselectively an epoxyamide, which was regioselectively opened by NaN3 in dimethyl formamide to give the title compound, C21H30N4O6. X-ray crystallography confirmed the relative stereochemistry of the title compound and the was determined by the use of D-glucose as the starting material. There are two molecules in the (Z′ = 2). The consists of two types of chains of O—H⋯O hydrogen-bonded molecules running parallel to the b axis, with each molecule acting as a donor and acceptor of one hydrogen bond.
Related literature
For the use of sulfur ylids to form epoxyamides, see: Assiego et al. (2004); Jenkinson et al. (2009; López-Herrera et al. (1996, 1997); Oña et al. (2010); Pino-González et al. (2003, 2008); Valpuesta Fernández et al. (1990).
Experimental
Crystal data
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Refinement
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Data collection: COLLECT (Nonius, 2001); cell DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS.
Supporting information
https://doi.org/10.1107/S1600536810048944/lh5169sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810048944/lh5169Isup2.hkl
The title compound was recrystallized from dichloromethane: m.p. 375–376 K; [α]D29 -2.28 (1.4, CH2Cl2).
In the absence of significant
Friedel pairs were merged and the was assigned from the use of D-glucose as the starting material.The H atoms were all located in a difference map, but those attached to carbon atoms were repositioned geometrically. The H atoms were initially refined with soft restraints on the bond lengths and angles to regularize their geometry (C—H in the range 0.93–0.98, O—H = 0.82 Å) and Uiso(H) (in the range 1.2–1.5 times Ueq of the parent atom), after which the positions were refined with riding constraints.
The stereoselective formation of epoxyamides from monosacharides and sulfur ylids and the subsequent regioselective epoxide opening has been utilized in the formation of iminosugars such as the seven-membered ring azepanes (Oña et al., 2010), pyrrolidines (Pino-González et al., 2008), pipecolic acid derivatives (Pino-González et al., 2008) and other monosaccharide derivatives as C-glycosides (López-Herrera et al., 1997) and branched
(Jenkinson et al., 2009). In order to obtain new products, key intermediates in iminosugar synthesis, the reaction of semiprotected dialdose 1 with N,N-diethyl-2-(dimethylsulfuranylidene)acetamide was investigated.Reaction of aldehyde 1, obtained from D-glucose, with the sulfur ylid gave epoxyamide 2 as the only product (Fig. 1). The subsequent regioselective opening of the epoxide with sodium azide, with acetic acid as a catalyst, gave the title compound 3. The product was confirmed, by both X-ray crystallography and the use of D-glucose as the starting material, to have the D-glycero-D-gluco stereochemistry (Fig. 2) arising from initial attack of the ylid on the re face of the aldehyde. This configuration can be predicted from a Felkin-Ahn model as corroborated for a number of aldehyde sugars with either free
or in cyclohemiacetalic form (Valpuesta Fernández et al., 1990; López-Herrera et al., 1996). In the present compound 1, the influence of 3-O-benzyl group plays a crucial role to obtain complete selectivity.There are two crystallographically distinct molecules in the
which are related by a pseudo 2-fold rotation axis (Fig 2). When the two molecules are mapped they show good overlap for the majority of the structure (Fig. 3) with RMS deviations of 1.0604 on the positions, 0.0140 for the bonds and 35.7787 for the torsion angles. The major difference between the two molecules is the orientation of the aromatic ring. The crystal exists as chains of hydrogen bonded molecules lying parallel to the b-axis, with each molecule acting as a donor and an acceptor of one hydrogen bond (Fig. 4). Only classical hydrogen bonding is considered. For one of the molecules in the the ethylamine moiety exhibits a greater degree of thermal motion than in the other.For the use of sulfur ylids to form epoxyamides, see: Assiego et al. (2004); Jenkinson et al. (2009; López-Herrera et al. (1996, 1997); Oña et al. (2010); Pino-González et al. (2003, 2008); Valpuesta Fernández et al. (1990).
Data collection: COLLECT (Nonius, 2001); cell
DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).C21H30N4O6 | F(000) = 928 |
Mr = 434.49 | Dx = 1.275 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 4645 reflections |
a = 13.0478 (4) Å | θ = 5–27° |
b = 10.5547 (3) Å | µ = 0.09 mm−1 |
c = 16.5552 (6) Å | T = 150 K |
β = 97.0347 (11)° | Block, colourless |
V = 2262.75 (13) Å3 | 0.20 × 0.20 × 0.20 mm |
Z = 4 |
Nonius KappaCCD diffractometer | 4270 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.042 |
ω scans | θmax = 27.5°, θmin = 5.1° |
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) | h = −16→16 |
Tmin = 0.92, Tmax = 0.98 | k = −13→12 |
15625 measured reflections | l = −21→21 |
5408 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.053 | H-atom parameters constrained |
wR(F2) = 0.122 | Method = Modified Sheldrick w = 1/[σ2(F2) + (0.04P)2 + 1.43P], where P = [max(Fo2,0) + 2Fc2]/3 |
S = 0.96 | (Δ/σ)max = 0.003 |
5408 reflections | Δρmax = 0.56 e Å−3 |
559 parameters | Δρmin = −0.44 e Å−3 |
1 restraint |
C21H30N4O6 | V = 2262.75 (13) Å3 |
Mr = 434.49 | Z = 4 |
Monoclinic, P21 | Mo Kα radiation |
a = 13.0478 (4) Å | µ = 0.09 mm−1 |
b = 10.5547 (3) Å | T = 150 K |
c = 16.5552 (6) Å | 0.20 × 0.20 × 0.20 mm |
β = 97.0347 (11)° |
Nonius KappaCCD diffractometer | 5408 independent reflections |
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) | 4270 reflections with I > 2σ(I) |
Tmin = 0.92, Tmax = 0.98 | Rint = 0.042 |
15625 measured reflections |
R[F2 > 2σ(F2)] = 0.053 | 1 restraint |
wR(F2) = 0.122 | H-atom parameters constrained |
S = 0.96 | Δρmax = 0.56 e Å−3 |
5408 reflections | Δρmin = −0.44 e Å−3 |
559 parameters |
x | y | z | Uiso*/Ueq | ||
O1 | 0.64815 (18) | 0.4052 (2) | 0.70138 (14) | 0.0323 | |
C2 | 0.6244 (3) | 0.5362 (3) | 0.7050 (2) | 0.0326 | |
O3 | 0.52450 (18) | 0.5540 (3) | 0.72847 (14) | 0.0375 | |
C4 | 0.4683 (3) | 0.6383 (4) | 0.6712 (2) | 0.0391 | |
O5 | 0.50934 (17) | 0.6130 (3) | 0.59658 (14) | 0.0358 | |
C6 | 0.6160 (2) | 0.5864 (4) | 0.6164 (2) | 0.0325 | |
C7 | 0.6459 (2) | 0.4740 (3) | 0.5665 (2) | 0.0298 | |
C8 | 0.6189 (2) | 0.3632 (3) | 0.61879 (18) | 0.0282 | |
C9 | 0.6733 (2) | 0.2397 (3) | 0.60611 (19) | 0.0293 | |
O10 | 0.64964 (17) | 0.1992 (2) | 0.52424 (13) | 0.0330 | |
C11 | 0.6496 (2) | 0.1379 (3) | 0.6682 (2) | 0.0308 | |
N12 | 0.6996 (2) | 0.0157 (3) | 0.6550 (2) | 0.0429 | |
N13 | 0.6700 (3) | −0.0417 (3) | 0.5909 (2) | 0.0477 | |
N14 | 0.6530 (4) | −0.1082 (4) | 0.5375 (3) | 0.0697 | |
C15 | 0.5332 (2) | 0.1219 (3) | 0.6642 (2) | 0.0329 | |
O16 | 0.48494 (19) | 0.0876 (3) | 0.59857 (15) | 0.0420 | |
N17 | 0.4860 (2) | 0.1522 (4) | 0.72949 (19) | 0.0511 | |
C18 | 0.5406 (3) | 0.1803 (5) | 0.8104 (2) | 0.0490 | |
C19 | 0.5848 (4) | 0.0643 (5) | 0.8548 (3) | 0.0700 | |
C20 | 0.3693 (4) | 0.1677 (7) | 0.7180 (3) | 0.0828 | |
C21 | 0.3191 (5) | 0.0650 (7) | 0.7556 (5) | 0.1107 | |
O23 | 0.75398 (16) | 0.4753 (2) | 0.56203 (14) | 0.0328 | |
C24 | 0.7781 (3) | 0.5480 (4) | 0.4939 (2) | 0.0465 | |
C25 | 0.8930 (3) | 0.5551 (4) | 0.4966 (2) | 0.0357 | |
C26 | 0.9436 (3) | 0.4845 (4) | 0.4428 (2) | 0.0437 | |
C27 | 1.0507 (3) | 0.4893 (4) | 0.4466 (3) | 0.0477 | |
C28 | 1.1072 (3) | 0.5638 (4) | 0.5032 (3) | 0.0470 | |
C29 | 1.0577 (3) | 0.6343 (4) | 0.5561 (2) | 0.0462 | |
C30 | 0.9513 (3) | 0.6311 (4) | 0.5530 (2) | 0.0431 | |
C31 | 0.3567 (3) | 0.6015 (5) | 0.6614 (2) | 0.0568 | |
C32 | 0.4884 (4) | 0.7751 (4) | 0.6964 (3) | 0.0572 | |
O33 | 0.85567 (16) | 0.4425 (2) | 0.97984 (13) | 0.0306 | |
C34 | 0.8314 (2) | 0.4732 (3) | 0.89580 (18) | 0.0263 | |
C35 | 0.8804 (2) | 0.5994 (3) | 0.87875 (19) | 0.0262 | |
O36 | 0.85475 (16) | 0.6307 (2) | 0.79389 (13) | 0.0281 | |
C37 | 0.8626 (2) | 0.7634 (3) | 0.7846 (2) | 0.0291 | |
O38 | 0.95612 (18) | 0.7968 (3) | 0.75537 (14) | 0.0387 | |
C39 | 1.0141 (2) | 0.8790 (3) | 0.8134 (2) | 0.0312 | |
O40 | 0.97597 (16) | 0.8530 (2) | 0.88876 (13) | 0.0313 | |
C41 | 0.8693 (2) | 0.8217 (3) | 0.8702 (2) | 0.0283 | |
C42 | 0.8428 (2) | 0.7125 (3) | 0.92412 (19) | 0.0266 | |
O43 | 0.73311 (15) | 0.7062 (2) | 0.92145 (13) | 0.0308 | |
C44 | 0.6988 (2) | 0.7753 (4) | 0.9865 (2) | 0.0413 | |
C45 | 0.5827 (2) | 0.7846 (3) | 0.9760 (2) | 0.0314 | |
C46 | 0.5195 (3) | 0.7125 (4) | 0.9202 (2) | 0.0397 | |
C47 | 0.4129 (3) | 0.7252 (4) | 0.9147 (2) | 0.0467 | |
C48 | 0.3685 (3) | 0.8093 (5) | 0.9639 (2) | 0.0484 | |
C49 | 0.4308 (3) | 0.8828 (4) | 1.0175 (3) | 0.0500 | |
C50 | 0.5372 (3) | 0.8715 (4) | 1.0240 (2) | 0.0425 | |
C53 | 1.1262 (3) | 0.8427 (4) | 0.8215 (2) | 0.0446 | |
C54 | 0.9960 (3) | 1.0157 (3) | 0.7890 (2) | 0.0430 | |
C56 | 0.8605 (2) | 0.3683 (3) | 0.83931 (19) | 0.0276 | |
N57 | 0.8102 (2) | 0.2462 (3) | 0.85459 (18) | 0.0352 | |
N58 | 0.8394 (2) | 0.1915 (3) | 0.91974 (19) | 0.0373 | |
N59 | 0.8557 (3) | 0.1267 (3) | 0.9747 (2) | 0.0522 | |
C69 | 0.9774 (2) | 0.3514 (3) | 0.84793 (19) | 0.0283 | |
O61 | 1.02124 (16) | 0.3219 (3) | 0.91594 (13) | 0.0351 | |
N62 | 1.0296 (2) | 0.3696 (3) | 0.78426 (16) | 0.0290 | |
C63 | 0.9861 (3) | 0.4068 (3) | 0.70130 (19) | 0.0329 | |
C67 | 1.1427 (2) | 0.3516 (4) | 0.7969 (2) | 0.0373 | |
C68 | 1.1979 (3) | 0.4704 (5) | 0.8269 (3) | 0.0514 | |
C60 | 0.9706 (3) | 0.2938 (4) | 0.6450 (2) | 0.0424 | |
H21 | 0.6795 | 0.5814 | 0.7411 | 0.0413* | |
H61 | 0.6595 | 0.6608 | 0.6102 | 0.0413* | |
H71 | 0.6058 | 0.4710 | 0.5120 | 0.0371* | |
H81 | 0.5427 | 0.3517 | 0.6105 | 0.0355* | |
H91 | 0.7502 | 0.2565 | 0.6153 | 0.0370* | |
H111 | 0.6786 | 0.1682 | 0.7219 | 0.0400* | |
H181 | 0.4892 | 0.2173 | 0.8431 | 0.0635* | |
H182 | 0.5959 | 0.2426 | 0.8051 | 0.0631* | |
H192 | 0.6168 | 0.0864 | 0.9086 | 0.1080* | |
H191 | 0.5289 | 0.0039 | 0.8588 | 0.1082* | |
H193 | 0.6370 | 0.0263 | 0.8254 | 0.1083* | |
H202 | 0.3507 | 0.2449 | 0.7451 | 0.0996* | |
H201 | 0.3400 | 0.1775 | 0.6607 | 0.0987* | |
H211 | 0.2434 | 0.0744 | 0.7441 | 0.1711* | |
H212 | 0.3432 | 0.0626 | 0.8148 | 0.1714* | |
H213 | 0.3425 | −0.0108 | 0.7288 | 0.1713* | |
H242 | 0.7502 | 0.6334 | 0.4980 | 0.0610* | |
H241 | 0.7465 | 0.5100 | 0.4427 | 0.0610* | |
H261 | 0.9034 | 0.4324 | 0.4038 | 0.0557* | |
H271 | 1.0850 | 0.4414 | 0.4092 | 0.0598* | |
H281 | 1.1810 | 0.5652 | 0.5047 | 0.0609* | |
H291 | 1.0965 | 0.6855 | 0.5947 | 0.0577* | |
H301 | 0.9178 | 0.6804 | 0.5901 | 0.0536* | |
H312 | 0.3196 | 0.6568 | 0.6209 | 0.0900* | |
H311 | 0.3303 | 0.6102 | 0.7125 | 0.0902* | |
H313 | 0.3496 | 0.5153 | 0.6438 | 0.0898* | |
H322 | 0.4522 | 0.8297 | 0.6550 | 0.0915* | |
H321 | 0.4641 | 0.7893 | 0.7485 | 0.0911* | |
H323 | 0.5634 | 0.7908 | 0.7003 | 0.0914* | |
H341 | 0.7558 | 0.4841 | 0.8852 | 0.0312* | |
H351 | 0.9560 | 0.5943 | 0.8920 | 0.0324* | |
H371 | 0.8030 | 0.7976 | 0.7487 | 0.0365* | |
H411 | 0.8236 | 0.8951 | 0.8718 | 0.0377* | |
H421 | 0.8789 | 0.7177 | 0.9801 | 0.0315* | |
H442 | 0.7240 | 0.7335 | 1.0401 | 0.0541* | |
H441 | 0.7271 | 0.8618 | 0.9869 | 0.0547* | |
H461 | 0.5489 | 0.6538 | 0.8859 | 0.0497* | |
H471 | 0.3707 | 0.6747 | 0.8759 | 0.0575* | |
H481 | 0.2945 | 0.8160 | 0.9609 | 0.0622* | |
H491 | 0.4014 | 0.9433 | 1.0501 | 0.0603* | |
H501 | 0.5802 | 0.9223 | 1.0620 | 0.0551* | |
H532 | 1.1655 | 0.9019 | 0.8600 | 0.0722* | |
H531 | 1.1339 | 0.7567 | 0.8419 | 0.0727* | |
H533 | 1.1517 | 0.8476 | 0.7682 | 0.0720* | |
H541 | 1.0285 | 1.0712 | 0.8310 | 0.0684* | |
H543 | 1.0243 | 1.0320 | 0.7386 | 0.0679* | |
H542 | 0.9224 | 1.0313 | 0.7813 | 0.0679* | |
H561 | 0.8352 | 0.3934 | 0.7826 | 0.0362* | |
H632 | 1.0367 | 0.4644 | 0.6817 | 0.0422* | |
H631 | 0.9207 | 0.4513 | 0.7039 | 0.0420* | |
H671 | 1.1587 | 0.2815 | 0.8359 | 0.0484* | |
H672 | 1.1632 | 0.3294 | 0.7432 | 0.0481* | |
H683 | 1.2715 | 0.4572 | 0.8302 | 0.0791* | |
H682 | 1.1808 | 0.4894 | 0.8820 | 0.0790* | |
H681 | 1.1772 | 0.5395 | 0.7892 | 0.0790* | |
H603 | 0.9415 | 0.3234 | 0.5905 | 0.0673* | |
H602 | 1.0366 | 0.2524 | 0.6431 | 0.0672* | |
H601 | 0.9232 | 0.2353 | 0.6685 | 0.0672* | |
H331 | 0.9169 | 0.4160 | 0.9902 | 0.0479* | |
H101 | 0.5900 | 0.1659 | 0.5196 | 0.0518* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0352 (12) | 0.0328 (13) | 0.0270 (12) | −0.0013 (10) | −0.0035 (9) | 0.0019 (10) |
C2 | 0.0323 (17) | 0.0333 (18) | 0.0311 (17) | −0.0026 (15) | −0.0002 (14) | 0.0028 (14) |
O3 | 0.0410 (13) | 0.0453 (15) | 0.0261 (12) | 0.0036 (12) | 0.0034 (10) | 0.0031 (11) |
C4 | 0.0401 (19) | 0.050 (2) | 0.0281 (17) | 0.0059 (17) | 0.0075 (14) | 0.0039 (17) |
O5 | 0.0290 (11) | 0.0503 (16) | 0.0287 (12) | 0.0092 (11) | 0.0060 (9) | 0.0062 (11) |
C6 | 0.0250 (15) | 0.0374 (19) | 0.0346 (18) | −0.0013 (14) | 0.0018 (13) | 0.0068 (15) |
C7 | 0.0222 (14) | 0.0347 (18) | 0.0319 (17) | −0.0003 (14) | 0.0013 (12) | 0.0060 (15) |
C8 | 0.0256 (15) | 0.0340 (17) | 0.0238 (15) | −0.0045 (14) | −0.0013 (12) | 0.0009 (14) |
C9 | 0.0235 (15) | 0.0362 (19) | 0.0277 (16) | −0.0034 (13) | 0.0017 (12) | 0.0028 (14) |
O10 | 0.0314 (11) | 0.0420 (14) | 0.0263 (11) | −0.0067 (11) | 0.0067 (9) | −0.0020 (11) |
C11 | 0.0300 (16) | 0.0332 (18) | 0.0293 (17) | −0.0038 (14) | 0.0037 (13) | 0.0036 (14) |
N12 | 0.0476 (18) | 0.0355 (17) | 0.0466 (19) | 0.0057 (14) | 0.0100 (15) | 0.0080 (15) |
N13 | 0.058 (2) | 0.0339 (18) | 0.055 (2) | 0.0004 (17) | 0.0242 (17) | 0.0059 (18) |
N14 | 0.108 (3) | 0.040 (2) | 0.067 (3) | 0.001 (2) | 0.034 (2) | −0.009 (2) |
C15 | 0.0317 (16) | 0.0377 (19) | 0.0292 (17) | −0.0093 (15) | 0.0031 (13) | 0.0018 (15) |
O16 | 0.0382 (13) | 0.0553 (17) | 0.0325 (13) | −0.0163 (12) | 0.0043 (10) | −0.0033 (12) |
N17 | 0.0348 (16) | 0.087 (3) | 0.0332 (17) | −0.0170 (17) | 0.0091 (13) | −0.0074 (18) |
C18 | 0.047 (2) | 0.069 (3) | 0.0325 (19) | −0.018 (2) | 0.0115 (16) | −0.0099 (19) |
C19 | 0.101 (4) | 0.069 (3) | 0.038 (2) | −0.033 (3) | −0.002 (2) | 0.011 (2) |
C20 | 0.057 (3) | 0.132 (6) | 0.066 (3) | −0.034 (3) | 0.031 (2) | −0.018 (3) |
C21 | 0.086 (4) | 0.084 (5) | 0.169 (7) | −0.012 (4) | 0.045 (5) | −0.009 (5) |
O23 | 0.0233 (10) | 0.0404 (14) | 0.0351 (12) | −0.0002 (10) | 0.0053 (9) | 0.0125 (11) |
C24 | 0.0349 (18) | 0.058 (3) | 0.048 (2) | 0.0060 (18) | 0.0101 (16) | 0.027 (2) |
C25 | 0.0320 (17) | 0.037 (2) | 0.0392 (19) | 0.0014 (15) | 0.0098 (15) | 0.0167 (16) |
C26 | 0.051 (2) | 0.037 (2) | 0.044 (2) | −0.0025 (18) | 0.0062 (17) | 0.0039 (17) |
C27 | 0.046 (2) | 0.050 (2) | 0.051 (2) | 0.011 (2) | 0.0215 (18) | 0.009 (2) |
C28 | 0.0343 (18) | 0.053 (3) | 0.056 (2) | 0.0025 (18) | 0.0127 (18) | 0.019 (2) |
C29 | 0.047 (2) | 0.042 (2) | 0.048 (2) | −0.0080 (18) | 0.0006 (17) | 0.0086 (19) |
C30 | 0.050 (2) | 0.040 (2) | 0.041 (2) | 0.0086 (18) | 0.0115 (17) | 0.0037 (17) |
C31 | 0.0342 (18) | 0.097 (4) | 0.040 (2) | 0.007 (2) | 0.0108 (16) | 0.011 (2) |
C32 | 0.077 (3) | 0.047 (3) | 0.051 (3) | 0.010 (2) | 0.021 (2) | 0.003 (2) |
O33 | 0.0273 (11) | 0.0394 (14) | 0.0251 (11) | 0.0026 (10) | 0.0037 (9) | 0.0038 (10) |
C34 | 0.0197 (14) | 0.0309 (17) | 0.0282 (16) | 0.0013 (13) | 0.0024 (12) | 0.0001 (14) |
C35 | 0.0214 (13) | 0.0323 (17) | 0.0241 (15) | −0.0006 (13) | 0.0001 (11) | −0.0002 (13) |
O36 | 0.0311 (11) | 0.0283 (12) | 0.0241 (11) | −0.0009 (10) | 0.0007 (8) | −0.0007 (9) |
C37 | 0.0290 (15) | 0.0296 (17) | 0.0280 (16) | 0.0002 (14) | 0.0007 (12) | 0.0006 (13) |
O38 | 0.0428 (13) | 0.0446 (15) | 0.0304 (12) | −0.0145 (12) | 0.0119 (10) | −0.0064 (11) |
C39 | 0.0292 (16) | 0.0349 (19) | 0.0298 (17) | −0.0044 (14) | 0.0052 (13) | −0.0019 (14) |
O40 | 0.0277 (11) | 0.0385 (13) | 0.0280 (11) | −0.0082 (10) | 0.0050 (9) | −0.0013 (10) |
C41 | 0.0245 (14) | 0.0286 (17) | 0.0319 (17) | −0.0013 (13) | 0.0034 (12) | −0.0028 (14) |
C42 | 0.0196 (13) | 0.0320 (17) | 0.0275 (16) | 0.0008 (13) | 0.0005 (12) | −0.0038 (14) |
O43 | 0.0218 (10) | 0.0407 (14) | 0.0307 (12) | −0.0016 (10) | 0.0059 (8) | −0.0080 (11) |
C44 | 0.0293 (16) | 0.056 (2) | 0.040 (2) | −0.0004 (17) | 0.0096 (14) | −0.0167 (18) |
C45 | 0.0286 (15) | 0.0357 (19) | 0.0319 (17) | −0.0009 (14) | 0.0110 (13) | 0.0028 (15) |
C46 | 0.0322 (17) | 0.047 (2) | 0.0408 (19) | 0.0026 (17) | 0.0085 (14) | −0.0041 (17) |
C47 | 0.0341 (18) | 0.059 (3) | 0.046 (2) | −0.0038 (18) | 0.0029 (16) | 0.002 (2) |
C48 | 0.0291 (17) | 0.066 (3) | 0.051 (2) | 0.0060 (19) | 0.0112 (16) | 0.016 (2) |
C49 | 0.042 (2) | 0.058 (3) | 0.054 (2) | 0.014 (2) | 0.0201 (19) | 0.000 (2) |
C50 | 0.0389 (19) | 0.049 (2) | 0.042 (2) | 0.0010 (18) | 0.0143 (15) | −0.0085 (18) |
C53 | 0.0336 (17) | 0.056 (3) | 0.046 (2) | 0.0030 (18) | 0.0125 (16) | 0.0080 (19) |
C54 | 0.050 (2) | 0.034 (2) | 0.046 (2) | 0.0001 (17) | 0.0091 (18) | 0.0056 (17) |
C56 | 0.0265 (15) | 0.0303 (17) | 0.0257 (16) | −0.0043 (13) | 0.0016 (12) | 0.0018 (14) |
N57 | 0.0379 (15) | 0.0300 (15) | 0.0365 (16) | −0.0061 (13) | −0.0008 (12) | 0.0003 (13) |
N58 | 0.0395 (16) | 0.0310 (16) | 0.0418 (18) | −0.0037 (14) | 0.0066 (13) | −0.0009 (15) |
N59 | 0.074 (2) | 0.0379 (19) | 0.0445 (19) | −0.0024 (18) | 0.0061 (17) | 0.0123 (16) |
C69 | 0.0293 (15) | 0.0288 (17) | 0.0267 (16) | 0.0029 (14) | 0.0025 (12) | −0.0012 (14) |
O61 | 0.0308 (11) | 0.0496 (15) | 0.0239 (11) | 0.0083 (11) | −0.0001 (9) | 0.0041 (11) |
N62 | 0.0288 (13) | 0.0348 (15) | 0.0237 (13) | 0.0020 (12) | 0.0045 (10) | 0.0013 (12) |
C63 | 0.0378 (17) | 0.0365 (19) | 0.0250 (16) | 0.0042 (15) | 0.0059 (13) | 0.0030 (14) |
C67 | 0.0282 (16) | 0.053 (2) | 0.0312 (17) | −0.0003 (16) | 0.0045 (13) | −0.0016 (17) |
C68 | 0.0390 (19) | 0.063 (3) | 0.053 (2) | −0.010 (2) | 0.0071 (17) | 0.001 (2) |
C60 | 0.0452 (19) | 0.050 (2) | 0.0302 (18) | 0.0101 (18) | −0.0017 (15) | −0.0052 (17) |
O1—C2 | 1.420 (4) | O33—C34 | 1.426 (4) |
O1—C8 | 1.444 (4) | O33—H331 | 0.844 |
C2—O3 | 1.418 (4) | C34—C35 | 1.518 (5) |
C2—C6 | 1.551 (5) | C34—C56 | 1.527 (5) |
C2—H21 | 0.999 | C34—H341 | 0.987 |
O3—C4 | 1.435 (4) | C35—O36 | 1.442 (4) |
C4—O5 | 1.430 (4) | C35—C42 | 1.523 (5) |
C4—C31 | 1.496 (5) | C35—H351 | 0.986 |
C4—C32 | 1.517 (6) | O36—C37 | 1.415 (4) |
O5—C6 | 1.419 (4) | C37—O38 | 1.411 (4) |
C6—C7 | 1.523 (5) | C37—C41 | 1.538 (5) |
C6—H61 | 0.981 | C37—H371 | 0.987 |
C7—C8 | 1.521 (5) | O38—C39 | 1.437 (4) |
C7—O23 | 1.422 (4) | C39—O40 | 1.426 (4) |
C7—H71 | 0.987 | C39—C53 | 1.503 (5) |
C8—C9 | 1.511 (5) | C39—C54 | 1.509 (5) |
C8—H81 | 0.994 | O40—C41 | 1.427 (4) |
C9—O10 | 1.419 (4) | C41—C42 | 1.524 (5) |
C9—C11 | 1.545 (4) | C41—H411 | 0.980 |
C9—H91 | 1.011 | C42—O43 | 1.429 (3) |
O10—H101 | 0.848 | C42—H421 | 0.989 |
C11—N12 | 1.474 (5) | O43—C44 | 1.417 (4) |
C11—C15 | 1.522 (4) | C44—C45 | 1.506 (4) |
C11—H111 | 0.977 | C44—H442 | 1.010 |
N12—N13 | 1.241 (5) | C44—H441 | 0.985 |
N13—N14 | 1.129 (5) | C45—C46 | 1.388 (5) |
C15—O16 | 1.241 (4) | C45—C50 | 1.393 (5) |
C15—N17 | 1.346 (5) | C46—C47 | 1.390 (5) |
N17—C18 | 1.469 (5) | C46—H461 | 0.952 |
N17—C20 | 1.520 (6) | C47—C48 | 1.379 (6) |
C18—C19 | 1.506 (7) | C47—H471 | 0.955 |
C18—H181 | 0.992 | C48—C49 | 1.369 (6) |
C18—H182 | 0.988 | C48—H481 | 0.963 |
C19—H192 | 0.965 | C49—C50 | 1.384 (5) |
C19—H191 | 0.978 | C49—H491 | 0.946 |
C19—H193 | 0.970 | C50—H501 | 0.955 |
C20—C21 | 1.446 (9) | C53—H532 | 0.990 |
C20—H202 | 0.975 | C53—H531 | 0.970 |
C20—H201 | 0.984 | C53—H533 | 0.981 |
C21—H211 | 0.988 | C54—H541 | 0.967 |
C21—H212 | 0.993 | C54—H543 | 0.969 |
C21—H213 | 0.982 | C54—H542 | 0.966 |
O23—C24 | 1.431 (4) | C56—N57 | 1.482 (4) |
C24—C25 | 1.497 (5) | C56—C69 | 1.524 (4) |
C24—H242 | 0.978 | C56—H561 | 0.992 |
C24—H241 | 0.982 | N57—N58 | 1.241 (4) |
C25—C26 | 1.388 (5) | N58—N59 | 1.137 (4) |
C25—C30 | 1.387 (5) | C69—O61 | 1.239 (4) |
C26—C27 | 1.392 (6) | C69—N62 | 1.338 (4) |
C26—H261 | 0.955 | N62—C63 | 1.474 (4) |
C27—C28 | 1.368 (6) | N62—C67 | 1.476 (4) |
C27—H271 | 0.952 | C63—C60 | 1.512 (5) |
C28—C29 | 1.370 (6) | C63—H632 | 0.981 |
C28—H281 | 0.960 | C63—H631 | 0.980 |
C29—C30 | 1.383 (5) | C67—C68 | 1.501 (6) |
C29—H291 | 0.937 | C67—H671 | 0.988 |
C30—H301 | 0.951 | C67—H672 | 0.987 |
C31—H312 | 0.972 | C68—H683 | 0.965 |
C31—H311 | 0.957 | C68—H682 | 0.986 |
C31—H313 | 0.956 | C68—H681 | 0.976 |
C32—H322 | 0.972 | C60—H603 | 0.986 |
C32—H321 | 0.968 | C60—H602 | 0.971 |
C32—H323 | 0.986 | C60—H601 | 0.988 |
C2—O1—C8 | 107.8 (2) | C34—O33—H331 | 111.4 |
O1—C2—O3 | 110.7 (3) | O33—C34—C35 | 109.5 (2) |
O1—C2—C6 | 106.5 (3) | O33—C34—C56 | 113.0 (3) |
O3—C2—C6 | 104.7 (2) | C35—C34—C56 | 112.4 (2) |
O1—C2—H21 | 110.3 | O33—C34—H341 | 107.2 |
O3—C2—H21 | 113.0 | C35—C34—H341 | 107.4 |
C6—C2—H21 | 111.4 | C56—C34—H341 | 107.0 |
C2—O3—C4 | 108.3 (2) | C34—C35—O36 | 109.2 (2) |
O3—C4—O5 | 103.9 (3) | C34—C35—C42 | 115.3 (2) |
O3—C4—C31 | 108.8 (3) | O36—C35—C42 | 104.5 (3) |
O5—C4—C31 | 108.7 (3) | C34—C35—H351 | 110.1 |
O3—C4—C32 | 110.6 (3) | O36—C35—H351 | 109.6 |
O5—C4—C32 | 110.2 (3) | C42—C35—H351 | 107.9 |
C31—C4—C32 | 114.2 (4) | C35—O36—C37 | 108.8 (2) |
C4—O5—C6 | 107.3 (2) | O36—C37—O38 | 111.2 (3) |
C2—C6—O5 | 103.9 (3) | O36—C37—C41 | 107.0 (3) |
C2—C6—C7 | 104.6 (3) | O38—C37—C41 | 105.2 (2) |
O5—C6—C7 | 109.7 (3) | O36—C37—H371 | 111.4 |
C2—C6—H61 | 113.5 | O38—C37—H371 | 110.7 |
O5—C6—H61 | 112.4 | C41—C37—H371 | 111.1 |
C7—C6—H61 | 112.2 | C37—O38—C39 | 109.2 (2) |
C6—C7—C8 | 101.5 (3) | O38—C39—O40 | 104.9 (2) |
C6—C7—O23 | 110.0 (3) | O38—C39—C53 | 109.5 (3) |
C8—C7—O23 | 109.7 (3) | O40—C39—C53 | 108.2 (3) |
C6—C7—H71 | 112.3 | O38—C39—C54 | 110.2 (3) |
C8—C7—H71 | 111.2 | O40—C39—C54 | 110.9 (3) |
O23—C7—H71 | 111.7 | C53—C39—C54 | 112.7 (3) |
C7—C8—O1 | 104.5 (3) | C39—O40—C41 | 106.9 (2) |
C7—C8—C9 | 116.0 (3) | C37—C41—O40 | 103.6 (2) |
O1—C8—C9 | 108.8 (2) | C37—C41—C42 | 104.2 (3) |
C7—C8—H81 | 108.2 | O40—C41—C42 | 109.5 (2) |
O1—C8—H81 | 108.2 | C37—C41—H411 | 112.1 |
C9—C8—H81 | 110.8 | O40—C41—H411 | 113.1 |
C8—C9—O10 | 110.0 (3) | C42—C41—H411 | 113.5 |
C8—C9—C11 | 111.8 (3) | C41—C42—C35 | 101.2 (2) |
O10—C9—C11 | 112.8 (3) | C41—C42—O43 | 108.3 (2) |
C8—C9—H91 | 107.6 | C35—C42—O43 | 109.3 (2) |
O10—C9—H91 | 107.0 | C41—C42—H421 | 113.1 |
C11—C9—H91 | 107.3 | C35—C42—H421 | 111.2 |
C9—O10—H101 | 107.6 | O43—C42—H421 | 113.1 |
C9—C11—N12 | 112.4 (3) | C42—O43—C44 | 111.2 (2) |
C9—C11—C15 | 109.2 (3) | O43—C44—C45 | 110.7 (3) |
N12—C11—C15 | 110.8 (3) | O43—C44—H442 | 110.1 |
C9—C11—H111 | 106.9 | C45—C44—H442 | 110.2 |
N12—C11—H111 | 107.0 | O43—C44—H441 | 109.2 |
C15—C11—H111 | 110.5 | C45—C44—H441 | 108.2 |
C11—N12—N13 | 117.1 (3) | H442—C44—H441 | 108.5 |
N12—N13—N14 | 169.4 (4) | C44—C45—C46 | 123.2 (3) |
C11—C15—O16 | 117.8 (3) | C44—C45—C50 | 118.0 (3) |
C11—C15—N17 | 119.4 (3) | C46—C45—C50 | 118.8 (3) |
O16—C15—N17 | 122.7 (3) | C45—C46—C47 | 119.9 (4) |
C15—N17—C18 | 124.1 (3) | C45—C46—H461 | 120.3 |
C15—N17—C20 | 118.4 (3) | C47—C46—H461 | 119.8 |
C18—N17—C20 | 117.3 (3) | C46—C47—C48 | 120.9 (4) |
N17—C18—C19 | 113.2 (4) | C46—C47—H471 | 118.7 |
N17—C18—H181 | 106.9 | C48—C47—H471 | 120.5 |
C19—C18—H181 | 107.4 | C47—C48—C49 | 119.3 (3) |
N17—C18—H182 | 109.3 | C47—C48—H481 | 120.5 |
C19—C18—H182 | 110.2 | C49—C48—H481 | 120.3 |
H181—C18—H182 | 109.8 | C48—C49—C50 | 120.8 (4) |
C18—C19—H192 | 110.5 | C48—C49—H491 | 120.2 |
C18—C19—H191 | 108.6 | C50—C49—H491 | 119.1 |
H192—C19—H191 | 109.7 | C45—C50—C49 | 120.4 (4) |
C18—C19—H193 | 110.0 | C45—C50—H501 | 119.2 |
H192—C19—H193 | 108.1 | C49—C50—H501 | 120.4 |
H191—C19—H193 | 109.9 | C39—C53—H532 | 108.6 |
N17—C20—C21 | 111.4 (6) | C39—C53—H531 | 109.1 |
N17—C20—H202 | 109.5 | H532—C53—H531 | 110.1 |
C21—C20—H202 | 106.1 | C39—C53—H533 | 109.8 |
N17—C20—H201 | 113.3 | H532—C53—H533 | 109.9 |
C21—C20—H201 | 110.6 | H531—C53—H533 | 109.3 |
H202—C20—H201 | 105.5 | C39—C54—H541 | 110.3 |
C20—C21—H211 | 109.7 | C39—C54—H543 | 109.6 |
C20—C21—H212 | 109.8 | H541—C54—H543 | 109.4 |
H211—C21—H212 | 112.4 | C39—C54—H542 | 108.6 |
C20—C21—H213 | 103.5 | H541—C54—H542 | 109.4 |
H211—C21—H213 | 110.7 | H543—C54—H542 | 109.4 |
H212—C21—H213 | 110.3 | C34—C56—N57 | 112.2 (3) |
C7—O23—C24 | 111.2 (2) | C34—C56—C69 | 110.4 (3) |
O23—C24—C25 | 108.6 (3) | N57—C56—C69 | 110.0 (3) |
O23—C24—H242 | 108.7 | C34—C56—H561 | 107.8 |
C25—C24—H242 | 109.4 | N57—C56—H561 | 106.9 |
O23—C24—H241 | 110.6 | C69—C56—H561 | 109.5 |
C25—C24—H241 | 111.1 | C56—N57—N58 | 117.2 (3) |
H242—C24—H241 | 108.4 | N57—N58—N59 | 169.2 (4) |
C24—C25—C26 | 120.5 (4) | C56—C69—O61 | 117.4 (3) |
C24—C25—C30 | 120.9 (4) | C56—C69—N62 | 120.7 (3) |
C26—C25—C30 | 118.6 (3) | O61—C69—N62 | 121.9 (3) |
C25—C26—C27 | 120.3 (4) | C69—N62—C63 | 126.7 (3) |
C25—C26—H261 | 118.6 | C69—N62—C67 | 117.9 (3) |
C27—C26—H261 | 121.1 | C63—N62—C67 | 115.5 (3) |
C26—C27—C28 | 120.4 (4) | N62—C63—C60 | 111.8 (3) |
C26—C27—H271 | 120.0 | N62—C63—H632 | 106.0 |
C28—C27—H271 | 119.6 | C60—C63—H632 | 109.2 |
C27—C28—C29 | 119.6 (4) | N62—C63—H631 | 109.0 |
C27—C28—H281 | 118.8 | C60—C63—H631 | 110.7 |
C29—C28—H281 | 121.6 | H632—C63—H631 | 110.0 |
C28—C29—C30 | 120.9 (4) | N62—C67—C68 | 111.7 (3) |
C28—C29—H291 | 119.4 | N62—C67—H671 | 108.5 |
C30—C29—H291 | 119.7 | C68—C67—H671 | 110.7 |
C25—C30—C29 | 120.3 (4) | N62—C67—H672 | 106.3 |
C25—C30—H301 | 119.6 | C68—C67—H672 | 108.9 |
C29—C30—H301 | 120.1 | H671—C67—H672 | 110.6 |
C4—C31—H312 | 108.3 | C67—C68—H683 | 109.4 |
C4—C31—H311 | 109.3 | C67—C68—H682 | 108.8 |
H312—C31—H311 | 110.4 | H683—C68—H682 | 108.2 |
C4—C31—H313 | 109.7 | C67—C68—H681 | 109.2 |
H312—C31—H313 | 109.9 | H683—C68—H681 | 109.9 |
H311—C31—H313 | 109.2 | H682—C68—H681 | 111.3 |
C4—C32—H322 | 108.6 | C63—C60—H603 | 108.8 |
C4—C32—H321 | 109.2 | C63—C60—H602 | 108.8 |
H322—C32—H321 | 110.6 | H603—C60—H602 | 111.0 |
C4—C32—H323 | 108.4 | C63—C60—H601 | 107.1 |
H322—C32—H323 | 109.8 | H603—C60—H601 | 111.7 |
H321—C32—H323 | 110.2 | H602—C60—H601 | 109.3 |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H21···O36 | 1.00 | 2.40 | 3.333 (5) | 155 |
C7—H71···O16i | 0.99 | 2.39 | 3.268 (5) | 147 |
C18—H182···O1 | 0.99 | 2.58 | 3.388 (5) | 139 |
C31—H312···O10i | 0.97 | 2.52 | 3.233 (5) | 130 |
C42—H421···O61ii | 0.99 | 2.31 | 3.216 (5) | 152 |
O33—H331···O40iii | 0.84 | 2.39 | 3.046 (5) | 135 |
O33—H331···O61 | 0.84 | 2.18 | 2.822 (5) | 133 |
O10—H101···O5iv | 0.85 | 2.25 | 2.849 (5) | 127 |
O10—H101···O16 | 0.85 | 2.17 | 2.858 (5) | 138 |
Symmetry codes: (i) −x+1, y+1/2, −z+1; (ii) −x+2, y+1/2, −z+2; (iii) −x+2, y−1/2, −z+2; (iv) −x+1, y−1/2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C21H30N4O6 |
Mr | 434.49 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 150 |
a, b, c (Å) | 13.0478 (4), 10.5547 (3), 16.5552 (6) |
β (°) | 97.0347 (11) |
V (Å3) | 2262.75 (13) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.20 × 0.20 × 0.20 |
Data collection | |
Diffractometer | Nonius KappaCCD |
Absorption correction | Multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) |
Tmin, Tmax | 0.92, 0.98 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15625, 5408, 4270 |
Rint | 0.042 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.053, 0.122, 0.96 |
No. of reflections | 5408 |
No. of parameters | 559 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.56, −0.44 |
Computer programs: COLLECT (Nonius, 2001), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), CAMERON (Watkin et al., 1996).
D—H···A | D—H | H···A | D···A | D—H···A |
O33—H331···O40i | 0.84 | 2.39 | 3.046 (5) | 135 |
O10—H101···O5ii | 0.85 | 2.25 | 2.849 (5) | 127 |
Symmetry codes: (i) −x+2, y−1/2, −z+2; (ii) −x+1, y−1/2, −z+1. |
Acknowledgements
We thank the Dirección General de Investigación Científica y Técnica of Spain (CTQ2007–66518/BQU) and the Consejería de Educación y Ciencia, Junta de Andalucia (FQM 158), for financial support.
References
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The stereoselective formation of epoxyamides from monosacharides and sulfur ylids and the subsequent regioselective epoxide opening has been utilized in the formation of iminosugars such as the seven-membered ring azepanes (Oña et al., 2010), pyrrolidines (Pino-González et al., 2008), pipecolic acid derivatives (Pino-González et al., 2008) and other monosaccharide derivatives as C-glycosides (López-Herrera et al., 1997) and branched furanoses (Jenkinson et al., 2009). In order to obtain new products, key intermediates in iminosugar synthesis, the reaction of semiprotected dialdose 1 with N,N-diethyl-2-(dimethylsulfuranylidene)acetamide was investigated.
Reaction of aldehyde 1, obtained from D-glucose, with the sulfur ylid gave epoxyamide 2 as the only product (Fig. 1). The subsequent regioselective opening of the epoxide with sodium azide, with acetic acid as a catalyst, gave the title compound 3. The product was confirmed, by both X-ray crystallography and the use of D-glucose as the starting material, to have the D-glycero-D-gluco stereochemistry (Fig. 2) arising from initial attack of the ylid on the re face of the aldehyde. This configuration can be predicted from a Felkin-Ahn model as corroborated for a number of aldehyde sugars with either free aldehydes or in cyclohemiacetalic form (Valpuesta Fernández et al., 1990; López-Herrera et al., 1996). In the present compound 1, the influence of 3-O-benzyl group plays a crucial role to obtain complete selectivity.
There are two crystallographically distinct molecules in the asymmetric unit which are related by a pseudo 2-fold rotation axis (Fig 2). When the two molecules are mapped they show good overlap for the majority of the structure (Fig. 3) with RMS deviations of 1.0604 on the positions, 0.0140 for the bonds and 35.7787 for the torsion angles. The major difference between the two molecules is the orientation of the aromatic ring. The crystal exists as chains of hydrogen bonded molecules lying parallel to the b-axis, with each molecule acting as a donor and an acceptor of one hydrogen bond (Fig. 4). Only classical hydrogen bonding is considered. For one of the molecules in the asymmetric unit the ethylamine moiety exhibits a greater degree of thermal motion than in the other.