Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270103008564/na1611sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103008564/na1611Isup2.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270103008564/na1611IIsup3.hkl |
CCDC references: 214402; 214403
Compound (I) was prepared? from (S)-6-tert-5-methoxy-6-methyl-3,6-dihydro-2H- 1,4-oxazin-2-one (65 mg, 0.33 mmol) in THF (3.5 ml), NaN(SiCH3)2 (685µl, 0.685 mmol, 2.1 equiv.) and (R)-(-)-epichlorohydrin (92 mg, 78 µl, 0.99 mmol, 3.0 mmol), with a reaction time of 24 h. CC (petrol ether/acetate, 70:30) yielded (I) as colorless crystals (40 mg, 47%, from diisopropyl ether by slow evaporation; m.p. 434.5–436 K). [α]D20= − 4.0 (c=0.55, CHCl3).
For the preparation of (II), to (1R,3S,6S)-6-tert-butyl-5-methoxy-6-methyl −4-aza-7-oxaspiro[2.5]oct-4-en-8-one-1-carbaldehyde) (64.0 mg, 0.253 mmol) in THF (3.0 ml) were added HP(O)(OMe)2 (20.88 µl, 0.228 mmol, 0.9 equiv.) and triethylamine (2.55 mg, 0.0253 mmol, 3.5 µl). The reaction mixture was stirred for 1 h at room temperature. The crude product was filtered off, dried and crystallized from diisopropyl ether (yield 86.6 mg, 97%; m.p. 434–436 K) by slow evaporation. [α]D20= + 19.2 (c=0.25, CHCl3).
All H atoms were positioned geometrically and refined as riding, with O—H distaces of 0.82 Å and C—H distances in the range 0.96–0.98 Å. Uiso values were constrained to be 1.5Ueq for H atoms from methyl groups and 1.2Ueq for other H atoms. The absolute configuration has been assigned on the basis of the known configuration of the reagents for both compounds. The Flack (1983) parameter for (I) could not be defined because the number of Friedel pairs was insufficient. In the case of (II), the Flack parameter is in agreement with the expected configuration.
For both compounds, data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1989a); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN (Molecular Structure Corporation, 1989b); program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PARST97 (Nardelli, 1996).
C13H21NO4 | Dx = 1.181 Mg m−3 |
Mr = 255.31 | Melting point: C13 H21 N O4 K |
Orthorhombic, P212121 | Cu Kα radiation, λ = 1.54178 Å |
a = 8.134 (3) Å | Cell parameters from 25 reflections |
b = 22.802 (2) Å | θ = 23.5–29.4° |
c = 7.744 (2) Å | µ = 0.72 mm−1 |
V = 1436.3 (7) Å3 | T = 293 K |
Z = 4 | Plate, colorless |
F(000) = 552 | 0.5 × 0.2 × 0.1 mm |
AFC5S Rigaku diffractometer | 1195 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.000 |
Graphite monochromator | θmax = 67.5°, θmin = 3.9° |
ω scan | h = −9→9 |
Absorption correction: analytical (De Meulenaer & Tompa, 1965) | k = −21→27 |
Tmin = 0.82, Tmax = 0.92 | l = −4→9 |
1480 measured reflections | 3 standard reflections every 150 reflections |
1480 independent reflections | intensity decay: <2% |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.052 | w = 1/[σ2(Fo2) + (0.1207P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.163 | (Δ/σ)max < 0.001 |
S = 1.02 | Δρmax = 0.40 e Å−3 |
1480 reflections | Δρmin = −0.16 e Å−3 |
170 parameters | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.017 (2) |
Primary atom site location: structure-invariant direct methods |
C13H21NO4 | V = 1436.3 (7) Å3 |
Mr = 255.31 | Z = 4 |
Orthorhombic, P212121 | Cu Kα radiation |
a = 8.134 (3) Å | µ = 0.72 mm−1 |
b = 22.802 (2) Å | T = 293 K |
c = 7.744 (2) Å | 0.5 × 0.2 × 0.1 mm |
AFC5S Rigaku diffractometer | 1195 reflections with I > 2σ(I) |
Absorption correction: analytical (De Meulenaer & Tompa, 1965) | Rint = 0.000 |
Tmin = 0.82, Tmax = 0.92 | 3 standard reflections every 150 reflections |
1480 measured reflections | intensity decay: <2% |
1480 independent reflections |
R[F2 > 2σ(F2)] = 0.052 | 0 restraints |
wR(F2) = 0.163 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.40 e Å−3 |
1480 reflections | Δρmin = −0.16 e Å−3 |
170 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.8882 (3) | 0.61951 (11) | 0.9203 (3) | 0.0650 (7) | |
C2 | 1.0281 (4) | 0.60630 (17) | 0.8383 (4) | 0.0611 (8) | |
O21 | 1.1576 (3) | 0.61483 (15) | 0.9133 (3) | 0.0822 (9) | |
C3 | 1.0161 (4) | 0.58000 (14) | 0.6645 (4) | 0.0560 (8) | |
N4 | 0.8584 (3) | 0.56568 (12) | 0.5973 (4) | 0.0579 (7) | |
C5 | 0.7336 (4) | 0.58646 (13) | 0.6730 (5) | 0.0562 (8) | |
O50 | 0.5803 (3) | 0.57494 (12) | 0.6146 (4) | 0.0729 (8) | |
C50 | 0.5710 (6) | 0.5411 (2) | 0.4581 (7) | 0.0978 (16) | |
H50A | 0.4583 | 0.5378 | 0.4227 | 0.147* | |
H50B | 0.6154 | 0.5027 | 0.4781 | 0.147* | |
H50C | 0.6332 | 0.5603 | 0.3691 | 0.147* | |
C6 | 0.7279 (4) | 0.62403 (14) | 0.8336 (4) | 0.0566 (8) | |
C61 | 0.6079 (5) | 0.59904 (19) | 0.9619 (5) | 0.0768 (11) | |
H61A | 0.4978 | 0.6048 | 0.9207 | 0.115* | |
H61B | 0.6210 | 0.6185 | 1.0710 | 0.115* | |
H61C | 0.6283 | 0.5578 | 0.9761 | 0.115* | |
C62 | 0.7006 (5) | 0.69059 (13) | 0.7918 (5) | 0.0693 (10) | |
C65 | 0.5314 (6) | 0.70043 (17) | 0.7102 (7) | 0.0913 (14) | |
H65A | 0.5312 | 0.6852 | 0.5946 | 0.137* | |
H65B | 0.5076 | 0.7417 | 0.7076 | 0.137* | |
H65C | 0.4492 | 0.6806 | 0.7773 | 0.137* | |
C63 | 0.7082 (7) | 0.7260 (2) | 0.9596 (7) | 0.0999 (15) | |
H63A | 0.7013 | 0.7671 | 0.9335 | 0.150* | |
H63B | 0.8100 | 0.7181 | 1.0178 | 0.150* | |
H63C | 0.6179 | 0.7151 | 1.0328 | 0.150* | |
C64 | 0.8325 (7) | 0.71294 (18) | 0.6685 (8) | 0.0990 (16) | |
H64A | 0.9386 | 0.7092 | 0.7219 | 0.149* | |
H64B | 0.8120 | 0.7534 | 0.6419 | 0.149* | |
H64C | 0.8302 | 0.6903 | 0.5641 | 0.149* | |
C7 | 1.1581 (5) | 0.53997 (17) | 0.6155 (5) | 0.0675 (9) | |
H7A | 1.2435 | 0.5336 | 0.7009 | 0.081* | |
H7B | 1.1338 | 0.5063 | 0.5434 | 0.081* | |
C8 | 1.1472 (4) | 0.59819 (18) | 0.5363 (4) | 0.0636 (9) | |
H8 | 1.2266 | 0.6268 | 0.5805 | 0.076* | |
C9 | 1.1008 (5) | 0.6063 (3) | 0.3483 (5) | 0.0844 (13) | |
H9A | 1.0419 | 0.5722 | 0.3063 | 0.101* | |
H9B | 1.0308 | 0.6404 | 0.3349 | 0.101* | |
O90 | 1.2456 (4) | 0.6137 (3) | 0.2571 (4) | 0.1191 (13) | |
H90 | 1.2255 | 0.6147 | 0.1534 | 0.179* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0625 (14) | 0.0829 (15) | 0.0497 (11) | −0.0006 (12) | −0.0023 (11) | −0.0036 (12) |
C2 | 0.0570 (18) | 0.080 (2) | 0.0459 (15) | −0.0039 (17) | 0.0018 (16) | 0.0067 (17) |
O21 | 0.0645 (16) | 0.127 (2) | 0.0548 (13) | −0.0073 (16) | −0.0135 (14) | −0.0034 (16) |
C3 | 0.0510 (17) | 0.0649 (18) | 0.0522 (16) | 0.0000 (14) | −0.0056 (16) | −0.0032 (15) |
N4 | 0.0519 (15) | 0.0601 (14) | 0.0618 (16) | −0.0018 (12) | −0.0017 (14) | −0.0086 (13) |
C5 | 0.0507 (17) | 0.0564 (15) | 0.0616 (18) | −0.0041 (14) | −0.0035 (16) | −0.0056 (16) |
O50 | 0.0527 (14) | 0.0784 (15) | 0.088 (2) | −0.0015 (11) | −0.0058 (14) | −0.0300 (14) |
C50 | 0.069 (3) | 0.116 (3) | 0.109 (3) | 0.000 (2) | −0.012 (3) | −0.060 (3) |
C6 | 0.0550 (17) | 0.0615 (16) | 0.0532 (16) | −0.0003 (14) | −0.0018 (16) | −0.0031 (15) |
C61 | 0.071 (2) | 0.084 (2) | 0.075 (2) | −0.006 (2) | 0.020 (2) | −0.001 (2) |
C62 | 0.076 (2) | 0.0545 (17) | 0.077 (2) | 0.0009 (16) | −0.001 (2) | −0.0087 (18) |
C65 | 0.101 (3) | 0.067 (2) | 0.107 (3) | 0.015 (2) | −0.020 (3) | −0.008 (2) |
C63 | 0.107 (3) | 0.086 (3) | 0.107 (4) | 0.004 (3) | −0.004 (3) | −0.040 (3) |
C64 | 0.114 (4) | 0.061 (2) | 0.122 (4) | −0.002 (2) | 0.026 (4) | 0.017 (3) |
C7 | 0.0554 (18) | 0.079 (2) | 0.068 (2) | 0.0078 (16) | 0.0004 (19) | 0.0019 (19) |
C8 | 0.0579 (19) | 0.084 (2) | 0.0493 (16) | −0.0108 (18) | 0.0038 (17) | 0.0032 (17) |
C9 | 0.065 (2) | 0.140 (4) | 0.0489 (17) | −0.007 (3) | 0.0116 (18) | −0.003 (2) |
O90 | 0.094 (2) | 0.201 (3) | 0.0621 (16) | −0.007 (3) | 0.0051 (17) | 0.012 (2) |
O1—C2 | 1.338 (4) | C62—C63 | 1.531 (6) |
O1—C6 | 1.470 (4) | C62—C65 | 1.531 (7) |
C2—O21 | 1.218 (4) | C65—H65A | 0.9600 |
C2—C3 | 1.477 (5) | C65—H65B | 0.9600 |
C3—N4 | 1.422 (4) | C65—H65C | 0.9600 |
C3—C8 | 1.514 (5) | C63—H63A | 0.9600 |
C3—C7 | 1.520 (5) | C63—H63B | 0.9600 |
N4—C5 | 1.264 (4) | C63—H63C | 0.9600 |
C5—O50 | 1.352 (4) | C64—H64A | 0.9600 |
C5—C6 | 1.510 (5) | C64—H64B | 0.9600 |
O50—C50 | 1.438 (5) | C64—H64C | 0.9600 |
C50—H50A | 0.9600 | C7—C8 | 1.465 (5) |
C50—H50B | 0.9600 | C7—H7A | 0.9700 |
C50—H50C | 0.9600 | C7—H7B | 0.9700 |
C6—C61 | 1.505 (5) | C8—C9 | 1.516 (5) |
C6—C62 | 1.567 (4) | C8—H8 | 0.9800 |
C61—H61A | 0.9600 | C9—O90 | 1.384 (5) |
C61—H61B | 0.9600 | C9—H9A | 0.9700 |
C61—H61C | 0.9600 | C9—H9B | 0.9700 |
C62—C64 | 1.524 (7) | O90—H90 | 0.8200 |
C2—O1—C6 | 123.6 (2) | C65—C62—C6 | 110.7 (3) |
O21—C2—O1 | 118.2 (3) | C62—C65—H65A | 109.5 |
O21—C2—C3 | 123.8 (3) | C62—C65—H65B | 109.5 |
O1—C2—C3 | 117.9 (3) | H65A—C65—H65B | 109.5 |
N4—C3—C2 | 119.1 (3) | C62—C65—H65C | 109.5 |
N4—C3—C8 | 117.3 (3) | H65A—C65—H65C | 109.5 |
C2—C3—C8 | 116.1 (3) | H65B—C65—H65C | 109.5 |
N4—C3—C7 | 117.1 (3) | C62—C63—H63A | 109.5 |
C2—C3—C7 | 114.9 (3) | C62—C63—H63B | 109.5 |
C8—C3—C7 | 57.7 (2) | H63A—C63—H63B | 109.5 |
C5—N4—C3 | 117.9 (3) | C62—C63—H63C | 109.5 |
N4—C5—O50 | 120.8 (3) | H63A—C63—H63C | 109.5 |
N4—C5—C6 | 128.2 (3) | H63B—C63—H63C | 109.5 |
O50—C5—C6 | 110.9 (3) | C62—C64—H64A | 109.5 |
C5—O50—C50 | 115.8 (3) | C62—C64—H64B | 109.5 |
O50—C50—H50A | 109.5 | H64A—C64—H64B | 109.5 |
O50—C50—H50B | 109.5 | C62—C64—H64C | 109.5 |
H50A—C50—H50B | 109.5 | H64A—C64—H64C | 109.5 |
O50—C50—H50C | 109.5 | H64B—C64—H64C | 109.5 |
H50A—C50—H50C | 109.5 | C8—C7—C3 | 60.9 (2) |
H50B—C50—H50C | 109.5 | C8—C7—H7A | 117.7 |
O1—C6—C61 | 104.3 (3) | C3—C7—H7A | 117.7 |
O1—C6—C5 | 108.0 (3) | C8—C7—H7B | 117.7 |
C61—C6—C5 | 110.4 (3) | C3—C7—H7B | 117.7 |
O1—C6—C62 | 106.7 (3) | H7A—C7—H7B | 114.8 |
C61—C6—C62 | 114.3 (3) | C7—C8—C3 | 61.3 (2) |
C5—C6—C62 | 112.6 (3) | C7—C8—C9 | 121.8 (4) |
C6—C61—H61A | 109.5 | C3—C8—C9 | 119.2 (3) |
C6—C61—H61B | 109.5 | C7—C8—H8 | 114.7 |
H61A—C61—H61B | 109.5 | C3—C8—H8 | 114.7 |
C6—C61—H61C | 109.5 | C9—C8—H8 | 114.7 |
H61A—C61—H61C | 109.5 | O90—C9—C8 | 107.0 (3) |
H61B—C61—H61C | 109.5 | O90—C9—H9A | 110.3 |
C64—C62—C63 | 109.1 (4) | C8—C9—H9A | 110.3 |
C64—C62—C65 | 109.0 (4) | O90—C9—H9B | 110.3 |
C63—C62—C65 | 108.0 (4) | C8—C9—H9B | 110.3 |
C64—C62—C6 | 110.7 (3) | H9A—C9—H9B | 108.6 |
C63—C62—C6 | 109.3 (4) | C9—O90—H90 | 109.5 |
C6—O1—C2—O21 | 165.8 (3) | N4—C5—C6—C62 | 101.4 (4) |
C6—O1—C2—C3 | −16.6 (5) | O50—C5—C6—C62 | −80.1 (4) |
O21—C2—C3—N4 | 172.7 (3) | O1—C6—C62—C64 | 62.3 (4) |
O1—C2—C3—N4 | −4.8 (5) | C61—C6—C62—C64 | 177.0 (4) |
O21—C2—C3—C8 | −38.5 (5) | C5—C6—C62—C64 | −56.0 (5) |
O1—C2—C3—C8 | 144.1 (3) | O1—C6—C62—C63 | −57.9 (4) |
O21—C2—C3—C7 | 26.2 (5) | C61—C6—C62—C63 | 56.9 (5) |
O1—C2—C3—C7 | −151.3 (3) | C5—C6—C62—C63 | −176.1 (4) |
C2—C3—N4—C5 | 13.9 (4) | O1—C6—C62—C65 | −176.7 (3) |
C8—C3—N4—C5 | −134.6 (3) | C61—C6—C62—C65 | −62.0 (4) |
C7—C3—N4—C5 | 159.6 (3) | C5—C6—C62—C65 | 65.0 (4) |
C3—N4—C5—O50 | 179.4 (3) | N4—C3—C7—C8 | 106.6 (4) |
C3—N4—C5—C6 | −2.3 (5) | C2—C3—C7—C8 | −106.3 (3) |
N4—C5—O50—C50 | −3.5 (5) | C3—C7—C8—C9 | −108.3 (4) |
C6—C5—O50—C50 | 177.8 (3) | N4—C3—C8—C7 | −106.3 (3) |
C2—O1—C6—C61 | 142.9 (3) | C2—C3—C8—C7 | 104.2 (3) |
C2—O1—C6—C5 | 25.4 (4) | N4—C3—C8—C9 | 6.2 (5) |
C2—O1—C6—C62 | −95.9 (4) | C2—C3—C8—C9 | −143.2 (4) |
N4—C5—C6—O1 | −16.1 (5) | C7—C3—C8—C9 | 112.6 (4) |
O50—C5—C6—O1 | 162.4 (3) | C7—C8—C9—O90 | −98.3 (5) |
N4—C5—C6—C61 | −129.6 (4) | C3—C8—C9—O90 | −170.9 (4) |
O50—C5—C6—C61 | 48.9 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
O90—H90···O21i | 0.82 | 1.94 | 2.757 (4) | 174 |
Symmetry code: (i) x, y, z−1. |
C15H26NO7P | F(000) = 388 |
Mr = 363.34 | Dx = 1.290 Mg m−3 |
Monoclinic, P21 | Cu Kα radiation, λ = 1.54178 Å |
a = 6.894 (1) Å | Cell parameters from 25 reflections |
b = 9.423 (1) Å | θ = 22.9–27.1° |
c = 14.428 (2) Å | µ = 1.61 mm−1 |
β = 93.266 (10)° | T = 293 K |
V = 935.8 (2) Å3 | Block, white |
Z = 2 | 0.4 × 0.3 × 0.3 mm |
AFC5S Rigaku diffractometer | 1578 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.018 |
Graphite monochromator | θmax = 67.5°, θmin = 5.6° |
ω scan | h = −6→8 |
Absorption correction: analytical (De Meulenaer & Tompa, 1965) | k = −11→10 |
Tmin = 0.555, Tmax = 0.650 | l = −17→17 |
1887 measured reflections | 3 standard reflections every 150 reflections |
1741 independent reflections | intensity decay: <2% |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.035 | w = 1/[σ2(Fo2) + (0.0698P)2 + 0.0119P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.102 | (Δ/σ)max < 0.001 |
S = 1.08 | Δρmax = 0.22 e Å−3 |
1741 reflections | Δρmin = −0.26 e Å−3 |
226 parameters | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
1 restraint | Extinction coefficient: 0.0119 (14) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983) |
Secondary atom site location: difference Fourier map | Absolute structure parameter: 0.03 (3) |
C15H26NO7P | V = 935.8 (2) Å3 |
Mr = 363.34 | Z = 2 |
Monoclinic, P21 | Cu Kα radiation |
a = 6.894 (1) Å | µ = 1.61 mm−1 |
b = 9.423 (1) Å | T = 293 K |
c = 14.428 (2) Å | 0.4 × 0.3 × 0.3 mm |
β = 93.266 (10)° |
AFC5S Rigaku diffractometer | 1578 reflections with I > 2σ(I) |
Absorption correction: analytical (De Meulenaer & Tompa, 1965) | Rint = 0.018 |
Tmin = 0.555, Tmax = 0.650 | 3 standard reflections every 150 reflections |
1887 measured reflections | intensity decay: <2% |
1741 independent reflections |
R[F2 > 2σ(F2)] = 0.035 | H-atom parameters constrained |
wR(F2) = 0.102 | Δρmax = 0.22 e Å−3 |
S = 1.08 | Δρmin = −0.26 e Å−3 |
1741 reflections | Absolute structure: Flack (1983) |
226 parameters | Absolute structure parameter: 0.03 (3) |
1 restraint |
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. |
x | y | z | Uiso*/Ueq | ||
P1 | 0.79564 (12) | 0.24272 (10) | −0.05426 (5) | 0.0544 (2) | |
O30 | 0.8771 (5) | 0.1094 (3) | −0.0854 (2) | 0.0733 (8) | |
O10 | 0.5687 (3) | 0.2403 (4) | −0.04970 (17) | 0.0657 (6) | |
C100 | 0.4611 (7) | 0.1103 (6) | −0.0421 (3) | 0.0809 (13) | |
H10A | 0.4457 | 0.0659 | −0.1020 | 0.121* | |
H10B | 0.3355 | 0.1308 | −0.0199 | 0.121* | |
H10C | 0.5302 | 0.0476 | 0.0005 | 0.121* | |
O20 | 0.8287 (4) | 0.3741 (3) | −0.11823 (17) | 0.0699 (7) | |
C200 | 0.7555 (7) | 0.3735 (6) | −0.2125 (3) | 0.0881 (14) | |
H20A | 0.7997 | 0.2898 | −0.2428 | 0.132* | |
H20B | 0.8014 | 0.4561 | −0.2435 | 0.132* | |
H20C | 0.6161 | 0.3743 | −0.2149 | 0.132* | |
C9 | 0.8899 (5) | 0.3057 (4) | 0.0578 (2) | 0.0525 (7) | |
H9 | 0.8296 | 0.3970 | 0.0715 | 0.063* | |
O90 | 1.0937 (4) | 0.3236 (3) | 0.0550 (2) | 0.0680 (7) | |
H91 | 1.1234 | 0.4043 | 0.0716 | 0.082* | |
C8 | 0.8447 (5) | 0.1990 (4) | 0.1319 (2) | 0.0526 (7) | |
H8 | 0.9125 | 0.1079 | 0.1288 | 0.063* | |
C7 | 0.6450 (5) | 0.1924 (4) | 0.1660 (2) | 0.0588 (9) | |
H7A | 0.5939 | 0.0996 | 0.1806 | 0.071* | |
H7B | 0.5493 | 0.2587 | 0.1396 | 0.071* | |
C3 | 0.8072 (4) | 0.2514 (4) | 0.22966 (19) | 0.0497 (7) | |
C2 | 0.8757 (5) | 0.1572 (4) | 0.3060 (2) | 0.0572 (9) | |
O21 | 0.8614 (6) | 0.0291 (3) | 0.3036 (2) | 0.0815 (10) | |
O1 | 0.9517 (4) | 0.2164 (3) | 0.38443 (16) | 0.0594 (6) | |
C6 | 0.9977 (5) | 0.3670 (4) | 0.3946 (2) | 0.0514 (7) | |
C61 | 0.9262 (5) | 0.4039 (5) | 0.4895 (2) | 0.0676 (10) | |
H61A | 0.7897 | 0.3841 | 0.4902 | 0.101* | |
H61B | 0.9485 | 0.5028 | 0.5019 | 0.101* | |
H61C | 0.9953 | 0.3481 | 0.5362 | 0.101* | |
C62 | 1.2223 (5) | 0.3823 (5) | 0.3880 (2) | 0.0609 (9) | |
C63 | 1.3266 (7) | 0.2729 (8) | 0.4514 (5) | 0.126 (3) | |
H63A | 1.2875 | 0.1791 | 0.4322 | 0.189* | |
H63B | 1.2932 | 0.2883 | 0.5143 | 0.189* | |
H63C | 1.4645 | 0.2826 | 0.4474 | 0.189* | |
C64 | 1.2768 (6) | 0.3579 (8) | 0.2897 (3) | 0.1012 (19) | |
H64A | 1.2267 | 0.4338 | 0.2510 | 0.152* | |
H64B | 1.2227 | 0.2695 | 0.2675 | 0.152* | |
H64C | 1.4157 | 0.3547 | 0.2879 | 0.152* | |
C65 | 1.2918 (7) | 0.5306 (6) | 0.4171 (4) | 0.0885 (14) | |
H65A | 1.4296 | 0.5374 | 0.4114 | 0.133* | |
H65B | 1.2626 | 0.5474 | 0.4805 | 0.133* | |
H65C | 1.2270 | 0.6001 | 0.3778 | 0.133* | |
C5 | 0.8858 (4) | 0.4474 (4) | 0.3192 (2) | 0.0490 (7) | |
N4 | 0.8008 (4) | 0.4017 (3) | 0.24524 (18) | 0.0485 (6) | |
O50 | 0.8819 (4) | 0.5886 (3) | 0.33880 (17) | 0.0619 (6) | |
C50 | 0.7817 (7) | 0.6787 (4) | 0.2709 (3) | 0.0732 (11) | |
H50A | 0.8398 | 0.6688 | 0.2123 | 0.110* | |
H50B | 0.7913 | 0.7757 | 0.2910 | 0.110* | |
H50C | 0.6475 | 0.6515 | 0.2642 | 0.110* |
U11 | U22 | U33 | U12 | U13 | U23 | |
P1 | 0.0614 (5) | 0.0517 (5) | 0.0502 (4) | 0.0004 (4) | 0.0052 (3) | −0.0026 (4) |
O30 | 0.097 (2) | 0.0550 (17) | 0.0686 (15) | 0.0149 (14) | 0.0084 (14) | −0.0178 (13) |
O10 | 0.0584 (13) | 0.0687 (15) | 0.0696 (13) | −0.0068 (14) | −0.0013 (10) | 0.0035 (15) |
C100 | 0.084 (3) | 0.087 (3) | 0.071 (2) | −0.032 (2) | −0.007 (2) | −0.004 (2) |
O20 | 0.0893 (18) | 0.0656 (17) | 0.0549 (13) | −0.0126 (14) | 0.0043 (11) | 0.0096 (12) |
C200 | 0.099 (3) | 0.103 (4) | 0.061 (2) | 0.000 (3) | −0.003 (2) | 0.019 (2) |
C9 | 0.0505 (16) | 0.0517 (18) | 0.0557 (16) | 0.0002 (15) | 0.0072 (13) | −0.0004 (15) |
O90 | 0.0538 (13) | 0.0723 (19) | 0.0784 (17) | −0.0120 (12) | 0.0071 (11) | −0.0032 (14) |
C8 | 0.0597 (18) | 0.0481 (18) | 0.0505 (16) | −0.0021 (14) | 0.0075 (13) | −0.0078 (13) |
C7 | 0.0589 (18) | 0.066 (2) | 0.0516 (16) | −0.0149 (16) | 0.0027 (14) | −0.0109 (16) |
C3 | 0.0542 (15) | 0.0486 (17) | 0.0462 (14) | −0.0026 (16) | 0.0025 (11) | −0.0057 (15) |
C2 | 0.065 (2) | 0.056 (3) | 0.0505 (18) | −0.0027 (16) | 0.0056 (15) | −0.0034 (15) |
O21 | 0.128 (3) | 0.0485 (18) | 0.0671 (16) | −0.0120 (16) | −0.0016 (17) | −0.0017 (13) |
O1 | 0.0724 (14) | 0.0493 (15) | 0.0550 (12) | −0.0078 (11) | −0.0087 (10) | 0.0029 (10) |
C6 | 0.0542 (17) | 0.0510 (19) | 0.0486 (15) | −0.0033 (15) | −0.0012 (12) | −0.0031 (14) |
C61 | 0.070 (2) | 0.083 (3) | 0.0494 (17) | −0.012 (2) | 0.0033 (15) | −0.0061 (18) |
C62 | 0.0449 (16) | 0.069 (2) | 0.0675 (19) | 0.0015 (16) | −0.0042 (14) | 0.0025 (18) |
C63 | 0.068 (3) | 0.128 (6) | 0.178 (6) | −0.001 (3) | −0.030 (3) | 0.066 (5) |
C64 | 0.053 (2) | 0.156 (6) | 0.096 (3) | −0.001 (3) | 0.019 (2) | −0.033 (4) |
C65 | 0.064 (2) | 0.086 (3) | 0.114 (4) | −0.023 (2) | 0.002 (2) | −0.018 (3) |
C5 | 0.0476 (17) | 0.0477 (19) | 0.0511 (16) | −0.0011 (14) | −0.0021 (13) | −0.0040 (14) |
N4 | 0.0488 (14) | 0.0471 (15) | 0.0496 (13) | −0.0002 (11) | 0.0019 (10) | −0.0043 (11) |
O50 | 0.0730 (16) | 0.0482 (13) | 0.0630 (14) | 0.0033 (12) | −0.0079 (12) | −0.0080 (12) |
C50 | 0.090 (3) | 0.050 (2) | 0.077 (3) | 0.0064 (19) | −0.009 (2) | 0.0008 (19) |
P1—O30 | 1.458 (3) | O1—C6 | 1.460 (4) |
P1—O20 | 1.568 (3) | C6—C5 | 1.502 (5) |
P1—O10 | 1.570 (2) | C6—C61 | 1.521 (5) |
P1—C9 | 1.808 (3) | C6—C62 | 1.564 (5) |
O10—C100 | 1.439 (5) | C61—H61A | 0.9600 |
C100—H10A | 0.9600 | C61—H61B | 0.9600 |
C100—H10B | 0.9600 | C61—H61C | 0.9600 |
C100—H10C | 0.9600 | C62—C64 | 1.506 (6) |
O20—C200 | 1.424 (5) | C62—C65 | 1.528 (6) |
C200—H20A | 0.9600 | C62—C63 | 1.530 (6) |
C200—H20B | 0.9600 | C63—H63A | 0.9600 |
C200—H20C | 0.9600 | C63—H63B | 0.9600 |
C9—O90 | 1.418 (4) | C63—H63C | 0.9600 |
C9—C8 | 1.513 (4) | C64—H64A | 0.9600 |
C9—H9 | 0.9800 | C64—H64B | 0.9600 |
O90—H91 | 0.8200 | C64—H64C | 0.9600 |
C8—C7 | 1.489 (5) | C65—H65A | 0.9600 |
C8—C3 | 1.530 (4) | C65—H65B | 0.9600 |
C8—H8 | 0.9800 | C65—H65C | 0.9600 |
C7—C3 | 1.513 (4) | C5—N4 | 1.264 (4) |
C7—H7A | 0.9700 | C5—O50 | 1.361 (4) |
C7—H7B | 0.9700 | O50—C50 | 1.442 (5) |
C3—N4 | 1.436 (5) | C50—H50A | 0.9600 |
C3—C2 | 1.472 (5) | C50—H50B | 0.9600 |
C2—O21 | 1.211 (4) | C50—H50C | 0.9600 |
C2—O1 | 1.341 (4) | ||
O30—P1—O20 | 115.31 (16) | C2—O1—C6 | 124.2 (3) |
O30—P1—O10 | 113.75 (18) | O1—C6—C5 | 108.5 (2) |
O20—P1—O10 | 102.41 (16) | O1—C6—C61 | 103.5 (3) |
O30—P1—C9 | 115.68 (17) | C5—C6—C61 | 110.9 (3) |
O20—P1—C9 | 102.13 (15) | O1—C6—C62 | 107.1 (3) |
O10—P1—C9 | 105.99 (14) | C5—C6—C62 | 112.2 (3) |
C100—O10—P1 | 122.4 (3) | C61—C6—C62 | 114.0 (3) |
O10—C100—H10A | 109.5 | C6—C61—H61A | 109.5 |
O10—C100—H10B | 109.5 | C6—C61—H61B | 109.5 |
H10A—C100—H10B | 109.5 | H61A—C61—H61B | 109.5 |
O10—C100—H10C | 109.5 | C6—C61—H61C | 109.5 |
H10A—C100—H10C | 109.5 | H61A—C61—H61C | 109.5 |
H10B—C100—H10C | 109.5 | H61B—C61—H61C | 109.5 |
C200—O20—P1 | 120.3 (3) | C64—C62—C65 | 107.9 (4) |
O20—C200—H20A | 109.5 | C64—C62—C63 | 109.0 (5) |
O20—C200—H20B | 109.5 | C65—C62—C63 | 108.8 (4) |
H20A—C200—H20B | 109.5 | C64—C62—C6 | 110.2 (3) |
O20—C200—H20C | 109.5 | C65—C62—C6 | 111.3 (3) |
H20A—C200—H20C | 109.5 | C63—C62—C6 | 109.5 (3) |
H20B—C200—H20C | 109.5 | C62—C63—H63A | 109.5 |
O90—C9—C8 | 110.1 (3) | C62—C63—H63B | 109.5 |
O90—C9—P1 | 108.6 (2) | H63A—C63—H63B | 109.5 |
C8—C9—P1 | 109.6 (2) | C62—C63—H63C | 109.5 |
O90—C9—H9 | 109.5 | H63A—C63—H63C | 109.5 |
C8—C9—H9 | 109.5 | H63B—C63—H63C | 109.5 |
P1—C9—H9 | 109.5 | C62—C64—H64A | 109.5 |
C9—O90—H91 | 109.5 | C62—C64—H64B | 109.5 |
C7—C8—C9 | 119.5 (3) | H64A—C64—H64B | 109.5 |
C7—C8—C3 | 60.1 (2) | C62—C64—H64C | 109.5 |
C9—C8—C3 | 119.3 (3) | H64A—C64—H64C | 109.5 |
C7—C8—H8 | 115.5 | H64B—C64—H64C | 109.5 |
C9—C8—H8 | 115.5 | C62—C65—H65A | 109.5 |
C3—C8—H8 | 115.5 | C62—C65—H65B | 109.5 |
C8—C7—C3 | 61.3 (2) | H65A—C65—H65B | 109.5 |
C8—C7—H7A | 117.6 | C62—C65—H65C | 109.5 |
C3—C7—H7A | 117.6 | H65A—C65—H65C | 109.5 |
C8—C7—H7B | 117.6 | H65B—C65—H65C | 109.5 |
C3—C7—H7B | 117.6 | N4—C5—O50 | 119.6 (3) |
H7A—C7—H7B | 114.7 | N4—C5—C6 | 129.4 (3) |
N4—C3—C2 | 119.3 (3) | O50—C5—C6 | 111.0 (3) |
N4—C3—C7 | 115.4 (3) | C5—N4—C3 | 116.8 (3) |
C2—C3—C7 | 115.3 (3) | C5—O50—C50 | 116.7 (3) |
N4—C3—C8 | 118.1 (3) | O50—C50—H50A | 109.5 |
C2—C3—C8 | 115.6 (3) | O50—C50—H50B | 109.5 |
C7—C3—C8 | 58.6 (2) | H50A—C50—H50B | 109.5 |
O21—C2—O1 | 117.8 (3) | O50—C50—H50C | 109.5 |
O21—C2—C3 | 123.8 (3) | H50A—C50—H50C | 109.5 |
O1—C2—C3 | 118.3 (3) | H50B—C50—H50C | 109.5 |
O30—P1—O10—C100 | 22.2 (3) | C8—C3—C2—O1 | 142.4 (3) |
O20—P1—O10—C100 | 147.3 (3) | O21—C2—O1—C6 | 173.0 (4) |
C9—P1—O10—C100 | −106.1 (3) | C3—C2—O1—C6 | −9.4 (5) |
O30—P1—O20—C200 | 59.9 (4) | C2—O1—C6—C5 | 19.5 (4) |
O10—P1—O20—C200 | −64.1 (3) | C2—O1—C6—C61 | 137.4 (3) |
C9—P1—O20—C200 | −173.8 (3) | C2—O1—C6—C62 | −101.8 (3) |
O30—P1—C9—O90 | 58.6 (3) | O1—C6—C62—C64 | 71.8 (4) |
O20—P1—C9—O90 | −67.5 (3) | C5—C6—C62—C64 | −47.2 (5) |
O10—P1—C9—O90 | −174.3 (3) | C61—C6—C62—C64 | −174.4 (4) |
O30—P1—C9—C8 | −61.7 (3) | O1—C6—C62—C65 | −168.5 (3) |
O20—P1—C9—C8 | 172.2 (2) | C5—C6—C62—C65 | 72.5 (4) |
O10—P1—C9—C8 | 65.4 (3) | C61—C6—C62—C65 | −54.7 (4) |
O90—C9—C8—C7 | 163.0 (3) | O1—C6—C62—C63 | −48.1 (5) |
P1—C9—C8—C7 | −77.6 (3) | C5—C6—C62—C63 | −167.1 (4) |
O90—C9—C8—C3 | 92.8 (3) | C61—C6—C62—C63 | 65.7 (5) |
P1—C9—C8—C3 | −147.8 (2) | O1—C6—C5—N4 | −15.8 (5) |
C9—C8—C7—C3 | −108.9 (3) | C61—C6—C5—N4 | −128.8 (4) |
C8—C7—C3—N4 | 108.7 (3) | C62—C6—C5—N4 | 102.4 (4) |
C8—C7—C3—C2 | −105.8 (3) | O1—C6—C5—O50 | 164.0 (3) |
C7—C8—C3—N4 | −104.2 (3) | C61—C6—C5—O50 | 50.9 (4) |
C9—C8—C3—N4 | 5.1 (4) | C62—C6—C5—O50 | −77.8 (3) |
C7—C8—C3—C2 | 105.3 (4) | O50—C5—N4—C3 | −178.8 (3) |
C9—C8—C3—C2 | −145.5 (3) | C6—C5—N4—C3 | 0.9 (5) |
C9—C8—C3—C7 | 109.2 (4) | C2—C3—N4—C5 | 11.9 (4) |
N4—C3—C2—O21 | 169.5 (4) | C7—C3—N4—C5 | 156.0 (3) |
C7—C3—C2—O21 | 25.4 (5) | C8—C3—N4—C5 | −137.6 (3) |
C8—C3—C2—O21 | −40.3 (5) | N4—C5—O50—C50 | −1.3 (5) |
N4—C3—C2—O1 | −7.8 (5) | C6—C5—O50—C50 | 178.9 (3) |
C7—C3—C2—O1 | −152.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O90—H91···O30i | 0.82 | 1.95 | 2.735 (4) | 161 |
Symmetry code: (i) −x+2, y+1/2, −z. |
Experimental details
(I) | (II) | |
Crystal data | ||
Chemical formula | C13H21NO4 | C15H26NO7P |
Mr | 255.31 | 363.34 |
Crystal system, space group | Orthorhombic, P212121 | Monoclinic, P21 |
Temperature (K) | 293 | 293 |
a, b, c (Å) | 8.134 (3), 22.802 (2), 7.744 (2) | 6.894 (1), 9.423 (1), 14.428 (2) |
α, β, γ (°) | 90, 90, 90 | 90, 93.266 (10), 90 |
V (Å3) | 1436.3 (7) | 935.8 (2) |
Z | 4 | 2 |
Radiation type | Cu Kα | Cu Kα |
µ (mm−1) | 0.72 | 1.61 |
Crystal size (mm) | 0.5 × 0.2 × 0.1 | 0.4 × 0.3 × 0.3 |
Data collection | ||
Diffractometer | AFC5S Rigaku diffractometer | AFC5S Rigaku diffractometer |
Absorption correction | Analytical (De Meulenaer & Tompa, 1965) | Analytical (De Meulenaer & Tompa, 1965) |
Tmin, Tmax | 0.82, 0.92 | 0.555, 0.650 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1480, 1480, 1195 | 1887, 1741, 1578 |
Rint | 0.000 | 0.018 |
(sin θ/λ)max (Å−1) | 0.599 | 0.599 |
Refinement | ||
R[F2 > 2σ(F2)], wR(F2), S | 0.052, 0.163, 1.02 | 0.035, 0.102, 1.08 |
No. of reflections | 1480 | 1741 |
No. of parameters | 170 | 226 |
No. of restraints | 0 | 1 |
H-atom treatment | H-atom parameters constrained | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.40, −0.16 | 0.22, −0.26 |
Absolute structure | ? | Flack (1983) |
Absolute structure parameter | ? | 0.03 (3) |
Computer programs: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1989a), MSC/AFC Diffractometer Control Software, TEXSAN (Molecular Structure Corporation, 1989b), SHELXS86 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), PARST97 (Nardelli, 1996).
O1—C2 | 1.338 (4) | C3—N4 | 1.422 (4) |
O1—C6 | 1.470 (4) | N4—C5 | 1.264 (4) |
C2—O21 | 1.218 (4) | C5—O50 | 1.352 (4) |
C2—C3 | 1.477 (5) | C5—C6 | 1.510 (5) |
O1—C2—C3—C8 | 144.1 (3) | C2—O1—C6—C61 | 142.9 (3) |
C8—C3—N4—C5 | −134.6 (3) | N4—C5—C6—C62 | 101.4 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
O90—H90···O21i | 0.82 | 1.94 | 2.757 (4) | 174 |
Symmetry code: (i) x, y, z−1. |
P1—O30 | 1.458 (3) | C2—O21 | 1.211 (4) |
P1—O20 | 1.568 (3) | C2—O1 | 1.341 (4) |
P1—O10 | 1.570 (2) | O1—C6 | 1.460 (4) |
P1—C9 | 1.808 (3) | C6—C5 | 1.502 (5) |
C3—N4 | 1.436 (5) | C5—N4 | 1.264 (4) |
C3—C2 | 1.472 (5) | C5—O50 | 1.361 (4) |
O30—P1—O20 | 115.31 (16) | O30—P1—C9 | 115.68 (17) |
O30—P1—O10 | 113.75 (18) | O20—P1—C9 | 102.13 (15) |
O20—P1—O10 | 102.41 (16) | O10—P1—C9 | 105.99 (14) |
C8—C3—C2—O1 | 142.4 (3) | C62—C6—C5—N4 | 102.4 (4) |
C2—O1—C6—C62 | −101.8 (3) | C8—C3—N4—C5 | −137.6 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O90—H91···O30i | 0.82 | 1.95 | 2.735 (4) | 161 |
Symmetry code: (i) −x+2, y+1/2, −z. |
Aminophosphonic acids are the analogues of natural amino acids in which the carboxylic acid group is replaced by the phosphonic group. Aminophosphonic acids and their esters and salts have attracted attention because of their broad applications, viz. in analytical chemistry (ligands for transitions metal cations), in agriculture (herbicides, pesticides and growth regulator in plants) and in medicine (antibiotics, antivirals and enzyme inhibitors) (Kalir et al., 1996; Hudson & Pianka, 1996; Kukhar & Hudson, 1999). In recent years, unnatural λ-amino acids have played an important role in the field of peptide chemistry. In this context, excitatory amino acids (EAAs) are of special interest because of their neurotransmission propetries in the central nervous system. The discovery that phosphono-substituted analogues of λ-amino acids increased potency and selectivity led to a major advance in the design of the N-methyl-D-aspartate (NMDA) receptor antagonists (Davies et al., 1981; Evans et al., 1982).
The importance of EAAs, in particular L-glutamic acid, (1), is becoming increasingly apparent. Specific and selective EAA agonists and antagonists have been developed (Hansen & Krogsgaard, 1990; Jonhson & Korner, 1988) There were postulated to be five defined EAA receptor subtypes (Monaghan et al., 1989). One of these, the L-amino-4-phosphonobutanoic acid [L—AP4; (2)] EAA receptor subtype, is delineated by a unique responsiveness to L—AP4 (Scheme 1). Compounds with the structure of (3) mimic L—AP4 more closely than do the cyclopentyl analogues (Kroona et al., 1991).
In this paper, we present the crystal structure of two compounds as the precursor to the synthesis of the cyclic analog of L—AP4, employing a chiral 6-tert-butyl-5-methoxy-6-methyl-3,6- dihydro-2H-1,4-oxazin-2-one (4).
A single-crystal X-ray diffraction study of these compounds was undertaken for a final examination of the absolute structure, establishing the configuration of the chiral atoms. The determination of the crystal structure revealed the reaction sequence, in which the attack of the deprotonated form of the oxazinone ring commenced with the terminal C atom in epichlorohydrin (Koch et al., 2003). Moreover, the structure of (II) was solved in order to elucidate the geometry around the P atom.
The substituents at C6 and C3 are in a cis conformation with respect to the heterocyclic ring, which confirms the proposed mechanism of the chemical process (Koch et al., 2003).
The heteroatomic ring in (I) has a twist-boat conformation, while in (II) the ring adopts a conformation between boat and twist-boat. The puckering parameters (Cremer & Pople, 1975) are as follows: QT= 0.232 (3) Å, ϕ2= −144.6 (8)° and θ2= 104.5 (8)° in (I), and QT= 0.194 (3) Å, ϕ2= −133.3 (8)° and θ2= 101.5 (8)° in (II), corresponding to the O1—C6—C5—N4—C3—C2 atom sequence, with a twofold pseudo-axis passing through the midpoint of the O1—C6 bond and atom C2 [asymmetry parameters Δ2= 0.01 (1) and Δ2= 0.03 (1) for (I)]. Four low values of the asymmetry parameters for (II) confirm that the conformation of the ring is between boat and twist-boat. A pseudo-twofold axis passes through the midpoint of the O1—C6 bond and atom C2 [Δ2= 0.03 (1) and Δ2= 0.03 (1)] and a mirror plane through the midpoint of the N4—C5 bond and atom C3 [Δs= 0.03 (1) and Δs= 0.03 (1); atom sequence as mentioned above].
An intermolecular O—H···O hydrogen bond exists in both structures. In (I), an O90—H90···O21i hydrogen bond is formed, but in (II), atom O21 does not act as an acceptor for hydrogen bonds. Here, the presence of the phosphonate group has the effect of changing the acceptor atom (O30 instead of O21), and thus an O90—H91—O30ii hydrogen bond is observed. These interactions create the chain graph-set motifs C(7) and C(5) in (I) and (II) (Bernstein et al., 1995), running along the c and b axis, respectively.
The P atom displays a distorted tetrahedral coordination geometry, with the largest deviations from the ideal values being for the O20—P1—C9 and O30—P1—C9 angles (the smallest and largest angles).
Bond distances and angles are in a good agreement with the expected values (Allen et al., 1987).