Buy article online - an online subscription or single-article purchase is required to access this article.
The title compound, methyl (2a
S,3
R,5
R,5a
S,6
S,6a
S,8
R,9a
S,10a
R,10b
R,10c
S)-8-(3-furyl)-2a,4,5,5a,6,6a,8,9,9a,10a,10b,10c-dodecahydro-3-hydroxy-2a,5a,6a,7-tetramethyl-5-(3-methylbut-2-enoyloxy)-2
H,3
H-cyclopenta[4′,5′]furo[2′,3′:6,5]benzo[
cd]isobenzofuran-6-acetate, C
32H
42O
8, was isolated from uncrushed green leaves of
Azadirachta indica A. Juss (neem) and has been found to possess antifeedant activity against
Spodptera litura. The conformations of the functional groups are similar to those of 3-desacetylsalannin, which was isolated from neem kernels. The molecules are linked into chains by intermolecular O—H
O hydrogen bonds.
Supporting information
CCDC reference: 199441
Fresh uncrushed green leaves of Azadirachta indica A. Juss (neem) (5 kg) were
soaked in hexane (25 l) for 24 h and the decanted n-hexane extract was
concentrated to 1 l in vacuo. The hexane extract was then partitioned
with 95% MeOH-water. The methanol layer was concentrated to dryness in
vacuo, resulting in a residue (16 g) which was subjected to primary
preparative high-performance liquid chromatography (HPLC) separation (Shimadzu
ODS column, 2 × 25 cm, 215 nm) using MeOH:H2O (70:30) as eluent at a
flow rate of 4 ml min-1 to yield eight peaks with retention times of 6.9,
11.9, 14.1, 18.3, 22.8, 32.2, 47.7 and 61.4 min. The peak with a retention
time of 18.3 min (262 mg) was further subjected to semi-preparative HPLC on an
RP18 column (E-Merck, ODS, 10 µm, 9.6 mm × 25 cm) using
acetonitrile-water (55:45) as eluent at a flow rate of 8 ml min-1. On
evaporation of the solvent, this yielded the title compound as a white solid
(80 mg) with a melting point of 457 K. This compound was identified as
2'3'-dehydrosalannol by comparison of its spectroscopic data (one- and
two-dimensional NMR) with published data (Garg & Bhakuni, 1985) (positions 2'
and 3' are numbered as C32 and C34, respectively, in Fig. 1). Good
diffraction-quality crystals of (I) were obtained from a solution of
acetonitrile and water (Ratio?) at 293 K.
In the absence of suitable anomalous scatters, Friedel equivalents could not be
used to determine the absolute structure. Refinement of the Flack parameter
(Flack, 1983) led to an inconclusive value (Flack & Bernadinelli, 2000) of
-0.3 (4). Therefore, the 133 Friedel equivalents were merged before the final
refinement. The enantiomer employed in the refined model was chosen to agree
with the accepted configuration of limonoids (Narayanan et al., 1964;
Harris et al., 1968; Henderson et al., 1968). The methyl and
hydroxy H atoms were constrained to an ideal geometry (C—H = 0.96 and O—H
= 0.82 Å) with Uiso(H) = 1.5Ueq(parent atom), but were
allowed to rotate freely about the C—C and C—O bonds, respectively. All
remaining H atoms were placed in geometrically idealized positions (C—H =
0.97–0.98 Å) and constrained to ride on their parent atom with
Uiso(H) = 1.2Ueq(C).
Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97 and PARST97 (Nardelli, 1995).
methyl
(2aS,3
R,5
R,5aS,6
S,6aS,8
R,9aS,10aR,10bR,10cS)]-
8-(3-furyl)-2a,4,5,5a,6,6a,8,9,9a,10
a,10
b,10
c-dodecahydro-3-hydroxy-
2a,5a,6a,7-tetramethyl-5-(3-methylbut-2-enoyloxy)-2H,3
H-
cyclopenta[4',5']furo[2',3':6,5]benzo[cd]isobenzofuran-6-acetate
top
Crystal data top
C32H42O8 | F(000) = 1192 |
Mr = 554.66 | Dx = 1.245 Mg m−3 |
Orthorhombic, P212121 | Cu Kα radiation, λ = 1.54178 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 25 reflections |
a = 7.220 (2) Å | θ = 15–30° |
b = 12.728 (2) Å | µ = 0.72 mm−1 |
c = 32.210 (6) Å | T = 293 K |
V = 2960.0 (11) Å3 | Needle, colourless |
Z = 4 | 0.33 × 0.23 × 0.13 mm |
Data collection top
Enraf-Nonius CAD-4 diffractometer | Rint = 0.028 |
Radiation source: fine-focus sealed tube | θmax = 75.1°, θmin = 2.7° |
Graphite monochromator | h = −2→8 |
non–profiled ω/2θ scans | k = −4→15 |
3407 measured reflections | l = −10→40 |
3280 independent reflections | 3 standard reflections every 60 min |
2091 reflections with I > 2σ(I) | intensity decay: 2% |
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)] = 0.045 | H-atom parameters constrained |
wR(F2) = 0.151 | Calculated w = 1/[σ2(Fo2) + (0.0876P)2 + 0.3127P] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max < 0.001 |
3280 reflections | Δρmax = 0.21 e Å−3 |
367 parameters | Δρmin = −0.20 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0025 (4) |
Crystal data top
C32H42O8 | V = 2960.0 (11) Å3 |
Mr = 554.66 | Z = 4 |
Orthorhombic, P212121 | Cu Kα radiation |
a = 7.220 (2) Å | µ = 0.72 mm−1 |
b = 12.728 (2) Å | T = 293 K |
c = 32.210 (6) Å | 0.33 × 0.23 × 0.13 mm |
Data collection top
Enraf-Nonius CAD-4 diffractometer | Rint = 0.028 |
3407 measured reflections | 3 standard reflections every 60 min |
3280 independent reflections | intensity decay: 2% |
2091 reflections with I > 2σ(I) | |
Refinement top
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.151 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.21 e Å−3 |
3280 reflections | Δρmin = −0.20 e Å−3 |
367 parameters | |
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 | Uiso*/Ueq | |
O1 | 0.1417 (4) | 0.84934 (18) | 0.16929 (8) | 0.0529 (7) | |
O3 | −0.0312 (4) | 0.8124 (2) | 0.25251 (10) | 0.0631 (8) | |
H3 | −0.0627 | 0.8694 | 0.2430 | 0.095* | |
O6 | 0.1722 (5) | 0.5228 (2) | 0.26136 (8) | 0.0605 (8) | |
O7 | 0.0670 (4) | 0.50150 (19) | 0.17641 (7) | 0.0492 (7) | |
O12 | 0.1783 (6) | 0.7262 (3) | 0.06896 (10) | 0.0809 (11) | |
O21 | −0.1623 (8) | 0.4012 (5) | −0.02194 (13) | 0.1267 (19) | |
O27 | 0.4531 (5) | 0.6904 (3) | 0.04168 (10) | 0.0824 (11) | |
O31 | 0.2388 (6) | 0.9958 (3) | 0.13869 (15) | 0.1210 (18) | |
C1 | 0.3137 (6) | 0.8420 (3) | 0.19281 (14) | 0.0516 (10) | |
H1 | 0.4075 | 0.8863 | 0.1795 | 0.062* | |
C2 | 0.2763 (7) | 0.8838 (3) | 0.23677 (14) | 0.0593 (11) | |
H2A | 0.3951 | 0.8948 | 0.2502 | 0.071* | |
H2B | 0.2180 | 0.9521 | 0.2341 | 0.071* | |
C3 | 0.1573 (7) | 0.8179 (3) | 0.26592 (14) | 0.0573 (11) | |
H3A | 0.1614 | 0.8490 | 0.2937 | 0.069* | |
C4 | 0.2348 (7) | 0.7062 (3) | 0.26795 (12) | 0.0528 (10) | |
C5 | 0.2588 (6) | 0.6687 (2) | 0.22303 (11) | 0.0444 (9) | |
H5 | 0.1345 | 0.6739 | 0.2110 | 0.053* | |
C6 | 0.2914 (7) | 0.5536 (3) | 0.22740 (12) | 0.0503 (10) | |
H6 | 0.4203 | 0.5425 | 0.2358 | 0.060* | |
C7 | 0.2588 (6) | 0.4965 (3) | 0.18728 (12) | 0.0470 (9) | |
H7 | 0.2964 | 0.4229 | 0.1903 | 0.056* | |
C8 | 0.3676 (6) | 0.5478 (3) | 0.15042 (13) | 0.0469 (9) | |
C9 | 0.3433 (6) | 0.6709 (2) | 0.14995 (12) | 0.0457 (9) | |
H9 | 0.2113 | 0.6826 | 0.1446 | 0.055* | |
C10 | 0.3821 (6) | 0.7261 (3) | 0.19251 (13) | 0.0467 (9) | |
C11 | 0.4435 (7) | 0.7217 (3) | 0.11341 (13) | 0.0591 (11) | |
H11A | 0.4631 | 0.7954 | 0.1195 | 0.071* | |
H11B | 0.5641 | 0.6890 | 0.1104 | 0.071* | |
C12 | 0.3424 (8) | 0.7129 (3) | 0.07354 (14) | 0.0601 (11) | |
C13 | 0.2799 (6) | 0.4369 (3) | 0.08379 (12) | 0.0539 (11) | |
C14 | 0.2521 (6) | 0.4987 (3) | 0.11677 (11) | 0.0454 (9) | |
C15 | 0.0571 (6) | 0.4919 (3) | 0.13197 (11) | 0.0450 (9) | |
H15 | −0.0173 | 0.5490 | 0.1202 | 0.054* | |
C16 | −0.0072 (7) | 0.3866 (3) | 0.11495 (13) | 0.0579 (11) | |
H16A | −0.1394 | 0.3871 | 0.1095 | 0.069* | |
H16B | 0.0212 | 0.3300 | 0.1341 | 0.069* | |
C17 | 0.1048 (6) | 0.3753 (3) | 0.07405 (13) | 0.0584 (12) | |
H17 | 0.1384 | 0.3012 | 0.0706 | 0.070* | |
C18 | 0.4497 (8) | 0.4180 (4) | 0.05835 (16) | 0.0759 (15) | |
H18A | 0.5409 | 0.4704 | 0.0647 | 0.114* | |
H18B | 0.4187 | 0.4218 | 0.0294 | 0.114* | |
H18C | 0.4986 | 0.3496 | 0.0646 | 0.114* | |
C19 | 0.5894 (7) | 0.7299 (4) | 0.20337 (16) | 0.0674 (13) | |
H19A | 0.6112 | 0.7847 | 0.2232 | 0.101* | |
H19B | 0.6599 | 0.7436 | 0.1787 | 0.101* | |
H19C | 0.6266 | 0.6636 | 0.2150 | 0.101* | |
C20 | −0.0003 (8) | 0.4095 (4) | 0.03642 (14) | 0.0671 (13) | |
C21 | −0.0621 (12) | 0.3462 (6) | 0.00635 (18) | 0.104 (2) | |
H21 | −0.0395 | 0.2744 | 0.0050 | 0.125* | |
C22 | −0.0644 (8) | 0.5111 (5) | 0.02672 (16) | 0.0810 (15) | |
H22 | −0.0441 | 0.5720 | 0.0420 | 0.097* | |
C23 | −0.1605 (9) | 0.5033 (7) | −0.00885 (19) | 0.0976 (19) | |
H23 | −0.2174 | 0.5590 | −0.0225 | 0.117* | |
C27 | 0.3650 (11) | 0.6814 (6) | 0.00128 (16) | 0.107 (2) | |
H27A | 0.4570 | 0.6662 | −0.0194 | 0.160* | |
H27B | 0.3043 | 0.7463 | −0.0054 | 0.160* | |
H27C | 0.2754 | 0.6257 | 0.0019 | 0.160* | |
C28 | 0.1052 (8) | 0.6177 (3) | 0.28159 (12) | 0.0633 (13) | |
H28A | 0.1083 | 0.6096 | 0.3115 | 0.076* | |
H28B | −0.0211 | 0.6326 | 0.2732 | 0.076* | |
C29 | 0.4066 (8) | 0.7039 (4) | 0.29547 (15) | 0.0764 (15) | |
H29A | 0.4552 | 0.6337 | 0.2964 | 0.115* | |
H29B | 0.3741 | 0.7259 | 0.3230 | 0.115* | |
H29C | 0.4985 | 0.7505 | 0.2843 | 0.115* | |
C30 | 0.5677 (6) | 0.5095 (3) | 0.15092 (16) | 0.0641 (12) | |
H30A | 0.5696 | 0.4340 | 0.1510 | 0.096* | |
H30B | 0.6286 | 0.5353 | 0.1754 | 0.096* | |
H30C | 0.6309 | 0.5349 | 0.1267 | 0.096* | |
C31 | 0.1212 (7) | 0.9304 (3) | 0.14339 (15) | 0.0616 (12) | |
C32 | −0.0604 (8) | 0.9285 (3) | 0.12375 (14) | 0.0637 (13) | |
H32 | −0.1290 | 0.8672 | 0.1271 | 0.076* | |
C33 | −0.0525 (10) | 1.1063 (4) | 0.09314 (18) | 0.0953 (19) | |
H33A | −0.1359 | 1.1482 | 0.0769 | 0.143* | |
H33B | 0.0607 | 1.0960 | 0.0781 | 0.143* | |
H33C | −0.0265 | 1.1416 | 0.1188 | 0.143* | |
C34 | −0.1382 (7) | 1.0037 (3) | 0.10186 (13) | 0.0589 (11) | |
C35 | −0.3265 (9) | 0.9922 (5) | 0.0841 (2) | 0.106 (2) | |
H35A | −0.3634 | 0.9198 | 0.0853 | 0.160* | |
H35B | −0.3258 | 1.0153 | 0.0557 | 0.160* | |
H35C | −0.4122 | 1.0342 | 0.0997 | 0.160* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0574 (18) | 0.0355 (11) | 0.0657 (16) | −0.0065 (12) | −0.0105 (15) | 0.0085 (12) |
O3 | 0.066 (2) | 0.0473 (15) | 0.075 (2) | 0.0018 (14) | −0.0058 (18) | −0.0090 (14) |
O6 | 0.090 (2) | 0.0413 (13) | 0.0501 (15) | −0.0048 (15) | 0.0047 (16) | 0.0032 (11) |
O7 | 0.0564 (18) | 0.0425 (12) | 0.0487 (14) | −0.0059 (13) | 0.0080 (13) | −0.0049 (11) |
O12 | 0.081 (3) | 0.096 (3) | 0.066 (2) | 0.015 (2) | −0.006 (2) | 0.0087 (19) |
O21 | 0.139 (5) | 0.162 (5) | 0.080 (3) | −0.051 (4) | −0.014 (3) | −0.002 (3) |
O27 | 0.080 (3) | 0.103 (3) | 0.0637 (19) | −0.007 (2) | 0.018 (2) | 0.0014 (19) |
O31 | 0.084 (3) | 0.092 (3) | 0.187 (4) | −0.036 (2) | −0.036 (3) | 0.087 (3) |
C1 | 0.051 (3) | 0.0351 (17) | 0.069 (3) | −0.0100 (17) | −0.014 (2) | 0.0005 (17) |
C2 | 0.072 (3) | 0.0323 (17) | 0.074 (3) | −0.0087 (19) | −0.009 (3) | −0.0088 (18) |
C3 | 0.066 (3) | 0.0465 (19) | 0.059 (2) | −0.007 (2) | −0.009 (2) | −0.0156 (19) |
C4 | 0.066 (3) | 0.046 (2) | 0.047 (2) | −0.004 (2) | −0.010 (2) | −0.0001 (16) |
C5 | 0.054 (2) | 0.0316 (15) | 0.0470 (19) | −0.0027 (17) | −0.0056 (19) | 0.0002 (14) |
C6 | 0.063 (3) | 0.0353 (17) | 0.052 (2) | 0.0037 (18) | −0.006 (2) | 0.0024 (16) |
C7 | 0.053 (3) | 0.0301 (15) | 0.058 (2) | 0.0035 (17) | −0.002 (2) | 0.0033 (16) |
C8 | 0.042 (2) | 0.0376 (16) | 0.061 (2) | 0.0011 (16) | 0.003 (2) | −0.0009 (17) |
C9 | 0.047 (2) | 0.0371 (16) | 0.053 (2) | −0.0064 (16) | 0.004 (2) | 0.0030 (16) |
C10 | 0.043 (2) | 0.0356 (16) | 0.062 (2) | −0.0066 (16) | −0.007 (2) | −0.0003 (17) |
C11 | 0.061 (3) | 0.052 (2) | 0.065 (3) | −0.007 (2) | 0.006 (2) | 0.0067 (19) |
C12 | 0.073 (3) | 0.051 (2) | 0.056 (2) | −0.003 (2) | 0.010 (3) | 0.008 (2) |
C13 | 0.060 (3) | 0.046 (2) | 0.056 (2) | 0.0007 (19) | 0.016 (2) | −0.0061 (17) |
C14 | 0.046 (2) | 0.0382 (16) | 0.052 (2) | 0.0015 (18) | 0.0080 (19) | −0.0008 (16) |
C15 | 0.051 (2) | 0.0394 (17) | 0.0445 (19) | −0.0035 (18) | 0.0111 (18) | −0.0063 (16) |
C16 | 0.063 (3) | 0.050 (2) | 0.060 (2) | −0.010 (2) | 0.012 (2) | −0.0103 (19) |
C17 | 0.068 (3) | 0.047 (2) | 0.060 (2) | −0.009 (2) | 0.020 (2) | −0.0172 (19) |
C18 | 0.071 (3) | 0.077 (3) | 0.079 (3) | 0.000 (3) | 0.029 (3) | −0.020 (3) |
C19 | 0.057 (3) | 0.064 (3) | 0.081 (3) | −0.006 (2) | −0.014 (3) | −0.004 (2) |
C20 | 0.073 (3) | 0.072 (3) | 0.056 (3) | −0.020 (2) | 0.013 (2) | −0.012 (2) |
C21 | 0.147 (6) | 0.098 (4) | 0.067 (3) | −0.042 (5) | −0.008 (4) | −0.011 (3) |
C22 | 0.073 (4) | 0.097 (4) | 0.073 (3) | 0.001 (3) | 0.005 (3) | −0.001 (3) |
C23 | 0.079 (4) | 0.130 (6) | 0.083 (4) | −0.004 (4) | 0.003 (3) | 0.023 (4) |
C27 | 0.125 (6) | 0.140 (6) | 0.056 (3) | −0.022 (5) | 0.013 (4) | −0.009 (3) |
C28 | 0.097 (4) | 0.048 (2) | 0.045 (2) | −0.005 (2) | 0.005 (3) | −0.0010 (17) |
C29 | 0.094 (4) | 0.067 (3) | 0.068 (3) | −0.003 (3) | −0.025 (3) | −0.003 (2) |
C30 | 0.048 (3) | 0.061 (2) | 0.084 (3) | 0.013 (2) | 0.004 (3) | −0.004 (3) |
C31 | 0.072 (3) | 0.0393 (18) | 0.074 (3) | −0.002 (2) | −0.006 (3) | 0.0131 (19) |
C32 | 0.075 (3) | 0.0413 (19) | 0.075 (3) | −0.011 (2) | −0.008 (3) | 0.016 (2) |
C33 | 0.116 (5) | 0.061 (3) | 0.109 (4) | −0.012 (3) | −0.017 (4) | 0.036 (3) |
C34 | 0.075 (3) | 0.050 (2) | 0.051 (2) | −0.003 (2) | 0.003 (2) | 0.0097 (18) |
C35 | 0.091 (4) | 0.098 (4) | 0.130 (5) | −0.008 (4) | −0.034 (4) | 0.049 (4) |
Geometric parameters (Å, º) top
O1—C31 | 1.335 (5) | C13—C17 | 1.521 (6) |
O1—C1 | 1.458 (5) | C14—C15 | 1.493 (6) |
O3—C3 | 1.430 (6) | C15—C16 | 1.520 (5) |
O3—H3 | 0.8200 | C15—H15 | 0.9800 |
O6—C6 | 1.446 (5) | C16—C17 | 1.553 (6) |
O6—C28 | 1.455 (5) | C16—H16A | 0.9700 |
O7—C7 | 1.430 (5) | C16—H16B | 0.9700 |
O7—C15 | 1.439 (4) | C17—C20 | 1.494 (7) |
O12—C12 | 1.206 (6) | C17—H17 | 0.9800 |
O21—C21 | 1.358 (8) | C18—H18A | 0.9600 |
O21—C23 | 1.366 (9) | C18—H18B | 0.9600 |
O27—C12 | 1.332 (5) | C18—H18C | 0.9600 |
O27—C27 | 1.453 (7) | C19—H19A | 0.9600 |
O31—C31 | 1.199 (5) | C19—H19B | 0.9600 |
C1—C2 | 1.537 (6) | C19—H19C | 0.9600 |
C1—C10 | 1.555 (5) | C20—C21 | 1.336 (7) |
C1—H1 | 0.9800 | C20—C22 | 1.409 (7) |
C2—C3 | 1.524 (6) | C21—H21 | 0.9300 |
C2—H2A | 0.9700 | C22—C23 | 1.343 (8) |
C2—H2B | 0.9700 | C22—H22 | 0.9300 |
C3—C4 | 1.529 (6) | C23—H23 | 0.9300 |
C3—H3A | 0.9800 | C27—H27A | 0.9600 |
C4—C29 | 1.525 (6) | C27—H27B | 0.9600 |
C4—C28 | 1.529 (6) | C27—H27C | 0.9600 |
C4—C5 | 1.533 (5) | C28—H28A | 0.9700 |
C5—C6 | 1.490 (4) | C28—H28B | 0.9700 |
C5—C10 | 1.514 (5) | C29—H29A | 0.9600 |
C5—H5 | 0.9800 | C29—H29B | 0.9600 |
C6—C7 | 1.501 (5) | C29—H29C | 0.9600 |
C6—H6 | 0.9800 | C30—H30A | 0.9600 |
C7—C8 | 1.566 (5) | C30—H30B | 0.9600 |
C7—H7 | 0.9800 | C30—H30C | 0.9600 |
C8—C14 | 1.504 (6) | C31—C32 | 1.456 (7) |
C8—C30 | 1.525 (6) | C32—C34 | 1.315 (6) |
C8—C9 | 1.577 (5) | C32—H32 | 0.9300 |
C9—C11 | 1.525 (5) | C33—C34 | 1.472 (7) |
C9—C10 | 1.566 (5) | C33—H33A | 0.9600 |
C9—H9 | 0.9800 | C33—H33B | 0.9600 |
C10—C19 | 1.538 (6) | C33—H33C | 0.9600 |
C11—C12 | 1.481 (6) | C34—C35 | 1.483 (7) |
C11—H11A | 0.9700 | C35—H35A | 0.9600 |
C11—H11B | 0.9700 | C35—H35B | 0.9600 |
C13—C14 | 1.337 (5) | C35—H35C | 0.9600 |
C13—C18 | 1.494 (6) | | |
| | | |
C31—O1—C1 | 118.0 (3) | O7—C15—H15 | 110.3 |
C3—O3—H3 | 109.5 | C14—C15—H15 | 110.3 |
C6—O6—C28 | 108.1 (3) | C16—C15—H15 | 110.3 |
C7—O7—C15 | 106.7 (3) | C15—C16—C17 | 103.2 (3) |
C21—O21—C23 | 106.1 (5) | C15—C16—H16A | 111.1 |
C12—O27—C27 | 116.4 (5) | C17—C16—H16A | 111.1 |
O1—C1—C2 | 107.9 (3) | C15—C16—H16B | 111.1 |
O1—C1—C10 | 109.2 (3) | C17—C16—H16B | 111.1 |
C2—C1—C10 | 113.0 (3) | H16A—C16—H16B | 109.1 |
O1—C1—H1 | 108.9 | C20—C17—C13 | 116.1 (4) |
C2—C1—H1 | 108.9 | C20—C17—C16 | 113.4 (4) |
C10—C1—H1 | 108.9 | C13—C17—C16 | 102.1 (3) |
C3—C2—C1 | 118.5 (3) | C20—C17—H17 | 108.3 |
C3—C2—H2A | 107.7 | C13—C17—H17 | 108.3 |
C1—C2—H2A | 107.7 | C16—C17—H17 | 108.3 |
C3—C2—H2B | 107.7 | C13—C18—H18A | 109.5 |
C1—C2—H2B | 107.7 | C13—C18—H18B | 109.5 |
H2A—C2—H2B | 107.1 | H18A—C18—H18B | 109.5 |
O3—C3—C2 | 112.2 (4) | C13—C18—H18C | 109.5 |
O3—C3—C4 | 108.4 (3) | H18A—C18—H18C | 109.5 |
C2—C3—C4 | 109.4 (4) | H18B—C18—H18C | 109.5 |
O3—C3—H3A | 109.0 | C10—C19—H19A | 109.5 |
C2—C3—H3A | 109.0 | C10—C19—H19B | 109.5 |
C4—C3—H3A | 109.0 | H19A—C19—H19B | 109.5 |
C29—C4—C28 | 108.4 (4) | C10—C19—H19C | 109.5 |
C29—C4—C3 | 109.9 (3) | H19A—C19—H19C | 109.5 |
C28—C4—C3 | 118.3 (4) | H19B—C19—H19C | 109.5 |
C29—C4—C5 | 116.8 (4) | C21—C20—C22 | 106.4 (6) |
C28—C4—C5 | 96.4 (3) | C21—C20—C17 | 125.6 (5) |
C3—C4—C5 | 106.9 (3) | C22—C20—C17 | 127.9 (4) |
C6—C5—C10 | 116.3 (4) | C20—C21—O21 | 110.7 (6) |
C6—C5—C4 | 103.6 (3) | C20—C21—H21 | 124.6 |
C10—C5—C4 | 121.9 (3) | O21—C21—H21 | 124.6 |
C6—C5—H5 | 104.4 | C23—C22—C20 | 106.9 (6) |
C10—C5—H5 | 104.4 | C23—C22—H22 | 126.5 |
C4—C5—H5 | 104.4 | C20—C22—H22 | 126.5 |
O6—C6—C5 | 104.1 (3) | C22—C23—O21 | 109.8 (6) |
O6—C6—C7 | 115.3 (3) | C22—C23—H23 | 125.1 |
C5—C6—C7 | 111.7 (3) | O21—C23—H23 | 125.1 |
O6—C6—H6 | 108.5 | O27—C27—H27A | 109.5 |
C5—C6—H6 | 108.5 | O27—C27—H27B | 109.5 |
C7—C6—H6 | 108.5 | H27A—C27—H27B | 109.5 |
O7—C7—C6 | 109.9 (3) | O27—C27—H27C | 109.5 |
O7—C7—C8 | 106.3 (3) | H27A—C27—H27C | 109.5 |
C6—C7—C8 | 111.9 (3) | H27B—C27—H27C | 109.5 |
O7—C7—H7 | 109.6 | O6—C28—C4 | 106.2 (4) |
C6—C7—H7 | 109.6 | O6—C28—H28A | 110.5 |
C8—C7—H7 | 109.6 | C4—C28—H28A | 110.5 |
C14—C8—C30 | 113.6 (3) | O6—C28—H28B | 110.5 |
C14—C8—C7 | 95.5 (3) | C4—C28—H28B | 110.5 |
C30—C8—C7 | 109.5 (3) | H28A—C28—H28B | 108.7 |
C14—C8—C9 | 110.2 (3) | C4—C29—H29A | 109.5 |
C30—C8—C9 | 115.0 (3) | C4—C29—H29B | 109.5 |
C7—C8—C9 | 111.5 (3) | H29A—C29—H29B | 109.5 |
C11—C9—C10 | 113.6 (3) | C4—C29—H29C | 109.5 |
C11—C9—C8 | 112.1 (3) | H29A—C29—H29C | 109.5 |
C10—C9—C8 | 114.7 (3) | H29B—C29—H29C | 109.5 |
C11—C9—H9 | 105.1 | C8—C30—H30A | 109.5 |
C10—C9—H9 | 105.1 | C8—C30—H30B | 109.5 |
C8—C9—H9 | 105.1 | H30A—C30—H30B | 109.5 |
C5—C10—C19 | 116.1 (4) | C8—C30—H30C | 109.5 |
C5—C10—C1 | 105.5 (3) | H30A—C30—H30C | 109.5 |
C19—C10—C1 | 106.2 (3) | H30B—C30—H30C | 109.5 |
C5—C10—C9 | 104.3 (3) | O31—C31—O1 | 122.5 (4) |
C19—C10—C9 | 112.8 (4) | O31—C31—C32 | 126.5 (4) |
C1—C10—C9 | 112.0 (3) | O1—C31—C32 | 111.0 (4) |
C12—C11—C9 | 113.8 (4) | C34—C32—C31 | 127.3 (4) |
C12—C11—H11A | 108.8 | C34—C32—H32 | 116.4 |
C9—C11—H11A | 108.8 | C31—C32—H32 | 116.4 |
C12—C11—H11B | 108.8 | C34—C33—H33A | 109.5 |
C9—C11—H11B | 108.8 | C34—C33—H33B | 109.5 |
H11A—C11—H11B | 107.7 | H33A—C33—H33B | 109.5 |
O12—C12—O27 | 121.7 (5) | C34—C33—H33C | 109.5 |
O12—C12—C11 | 125.4 (5) | H33A—C33—H33C | 109.5 |
O27—C12—C11 | 112.9 (5) | H33B—C33—H33C | 109.5 |
C14—C13—C18 | 130.9 (4) | C32—C34—C33 | 124.7 (5) |
C14—C13—C17 | 110.0 (4) | C32—C34—C35 | 121.8 (4) |
C18—C13—C17 | 119.1 (3) | C33—C34—C35 | 113.5 (5) |
C13—C14—C15 | 111.6 (4) | C34—C35—H35A | 109.5 |
C13—C14—C8 | 137.2 (4) | C34—C35—H35B | 109.5 |
C15—C14—C8 | 108.1 (3) | H35A—C35—H35B | 109.5 |
O7—C15—C14 | 105.9 (3) | C34—C35—H35C | 109.5 |
O7—C15—C16 | 116.7 (3) | H35A—C35—H35C | 109.5 |
C14—C15—C16 | 102.8 (3) | H35B—C35—H35C | 109.5 |
| | | |
C31—O1—C1—C2 | 99.9 (4) | C11—C9—C10—C19 | −57.5 (5) |
C31—O1—C1—C10 | −137.0 (4) | C8—C9—C10—C19 | 73.2 (4) |
O1—C1—C2—C3 | 71.1 (4) | C11—C9—C10—C1 | 62.2 (5) |
C10—C1—C2—C3 | −49.6 (5) | C8—C9—C10—C1 | −167.1 (3) |
C1—C2—C3—O3 | −67.8 (5) | C10—C9—C11—C12 | −149.1 (4) |
C1—C2—C3—C4 | 52.5 (5) | C8—C9—C11—C12 | 78.9 (5) |
O3—C3—C4—C29 | −160.6 (4) | C27—O27—C12—O12 | −0.8 (7) |
C2—C3—C4—C29 | 76.8 (4) | C27—O27—C12—C11 | −179.4 (5) |
O3—C3—C4—C28 | −35.4 (5) | C9—C11—C12—O12 | 43.0 (6) |
C2—C3—C4—C28 | −158.0 (4) | C9—C11—C12—O27 | −138.5 (4) |
O3—C3—C4—C5 | 71.7 (4) | C18—C13—C14—C15 | −180.0 (5) |
C2—C3—C4—C5 | −50.8 (5) | C17—C13—C14—C15 | −3.0 (5) |
C29—C4—C5—C6 | 69.2 (5) | C18—C13—C14—C8 | −23.1 (8) |
C28—C4—C5—C6 | −45.2 (4) | C17—C13—C14—C8 | 153.9 (4) |
C3—C4—C5—C6 | −167.3 (4) | C30—C8—C14—C13 | −8.4 (6) |
C29—C4—C5—C10 | −64.2 (5) | C7—C8—C14—C13 | −122.4 (5) |
C28—C4—C5—C10 | −178.6 (4) | C9—C8—C14—C13 | 122.3 (5) |
C3—C4—C5—C10 | 59.3 (5) | C30—C8—C14—C15 | 149.0 (3) |
C28—O6—C6—C5 | −11.8 (4) | C7—C8—C14—C15 | 35.0 (3) |
C28—O6—C6—C7 | −134.5 (4) | C9—C8—C14—C15 | −80.3 (4) |
C10—C5—C6—O6 | 173.5 (3) | C7—O7—C15—C14 | −9.0 (4) |
C4—C5—C6—O6 | 36.9 (4) | C7—O7—C15—C16 | 104.6 (4) |
C10—C5—C6—C7 | −61.5 (5) | C13—C14—C15—O7 | 145.0 (3) |
C4—C5—C6—C7 | 161.9 (4) | C8—C14—C15—O7 | −18.7 (4) |
C15—O7—C7—C6 | 153.8 (3) | C13—C14—C15—C16 | 22.1 (4) |
C15—O7—C7—C8 | 32.5 (4) | C8—C14—C15—C16 | −141.6 (3) |
O6—C6—C7—O7 | 51.9 (4) | O7—C15—C16—C17 | −146.3 (4) |
C5—C6—C7—O7 | −66.7 (4) | C14—C15—C16—C17 | −30.9 (4) |
O6—C6—C7—C8 | 169.8 (3) | C14—C13—C17—C20 | 107.0 (4) |
C5—C6—C7—C8 | 51.2 (5) | C18—C13—C17—C20 | −75.6 (5) |
O7—C7—C8—C14 | −40.9 (3) | C14—C13—C17—C16 | −16.9 (5) |
C6—C7—C8—C14 | −160.9 (3) | C18—C13—C17—C16 | 160.5 (4) |
O7—C7—C8—C30 | −158.3 (3) | C15—C16—C17—C20 | −96.5 (4) |
C6—C7—C8—C30 | 81.7 (4) | C15—C16—C17—C13 | 29.2 (4) |
O7—C7—C8—C9 | 73.3 (4) | C13—C17—C20—C21 | 131.3 (6) |
C6—C7—C8—C9 | −46.7 (5) | C16—C17—C20—C21 | −110.9 (6) |
C14—C8—C9—C11 | −73.5 (4) | C13—C17—C20—C22 | −53.3 (7) |
C30—C8—C9—C11 | 56.4 (5) | C16—C17—C20—C22 | 64.5 (6) |
C7—C8—C9—C11 | −178.2 (3) | C22—C20—C21—O21 | −0.2 (8) |
C14—C8—C9—C10 | 155.0 (3) | C17—C20—C21—O21 | 176.1 (5) |
C30—C8—C9—C10 | −75.1 (5) | C23—O21—C21—C20 | 0.6 (8) |
C7—C8—C9—C10 | 50.3 (5) | C21—C20—C22—C23 | −0.3 (7) |
C6—C5—C10—C19 | −65.1 (5) | C17—C20—C22—C23 | −176.4 (5) |
C4—C5—C10—C19 | 63.0 (5) | C20—C22—C23—O21 | 0.7 (7) |
C6—C5—C10—C1 | 177.7 (3) | C21—O21—C23—C22 | −0.8 (7) |
C4—C5—C10—C1 | −54.2 (5) | C6—O6—C28—C4 | −17.8 (4) |
C6—C5—C10—C9 | 59.6 (4) | C29—C4—C28—O6 | −82.8 (4) |
C4—C5—C10—C9 | −172.3 (4) | C3—C4—C28—O6 | 151.3 (3) |
O1—C1—C10—C5 | −76.0 (4) | C5—C4—C28—O6 | 38.2 (4) |
C2—C1—C10—C5 | 44.0 (4) | C1—O1—C31—O31 | 0.7 (7) |
O1—C1—C10—C19 | 160.3 (3) | C1—O1—C31—C32 | −177.6 (3) |
C2—C1—C10—C19 | −79.7 (4) | O31—C31—C32—C34 | −9.7 (9) |
O1—C1—C10—C9 | 36.8 (4) | O1—C31—C32—C34 | 168.5 (5) |
C2—C1—C10—C9 | 156.8 (3) | C31—C32—C34—C33 | 0.0 (8) |
C11—C9—C10—C5 | 175.8 (3) | C31—C32—C34—C35 | −179.0 (5) |
C8—C9—C10—C5 | −53.5 (4) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3···O6i | 0.82 | 2.11 | 2.900 (4) | 161 |
Symmetry code: (i) −x, y+1/2, −z+1/2. |
Experimental details
Crystal data |
Chemical formula | C32H42O8 |
Mr | 554.66 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 293 |
a, b, c (Å) | 7.220 (2), 12.728 (2), 32.210 (6) |
V (Å3) | 2960.0 (11) |
Z | 4 |
Radiation type | Cu Kα |
µ (mm−1) | 0.72 |
Crystal size (mm) | 0.33 × 0.23 × 0.13 |
|
Data collection |
Diffractometer | Enraf-Nonius CAD-4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3407, 3280, 2091 |
Rint | 0.028 |
(sin θ/λ)max (Å−1) | 0.627 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.151, 1.02 |
No. of reflections | 3280 |
No. of parameters | 367 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.21, −0.20 |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3···O6i | 0.82 | 2.11 | 2.900 (4) | 161 |
Symmetry code: (i) −x, y+1/2, −z+1/2. |
Subscribe to Acta Crystallographica Section C: Structural Chemistry
The full text of this article is available to subscribers to the journal.
If you have already registered and are using a computer listed in your registration details, please email
support@iucr.org for assistance.
Azadirachta indica A. Juss, an indigenous tree of the Indian subcontinent, has attracted the attention of many chemists and biologists all over the world during the past two decades, due to the plethora of biological activities found in the compounds extracted therefrom, in particular insect-antifeedant and growth-inhibition activities (Singh, 1993; Eppler, 1995; Locke, 1995; Schmutterer, 1995). The title compound, (I), was isolated from the hexane extract of uncrushed green neem leaves and purified by preparative high-performance liquid chromatography techniques.
The antifeedant activity of (I) against Spodptera litura (Suresh et al., 2002) is similar to that of 3-desacetylsalannin (DAS) (Kabaleeswaran et al., 1999), which was isolated from neem kernels. The difference between the structure of (I) and that of DAS is that in (I), a 3-methylbutenoyl (O-senecioxy ester) group has replaced the 2-methylbutenoyl (O-tigloyl) group at C1 in DAS. Due to this difference in the chemical structure, there is a conformational variation in the orientation of this functional group in these structures, and this is evident in the different values for the C1—O1—C31—C32 dihedral angle [-177.6 (3)° in (I) and -171.9 (2)° in DAS]. Other functional groups, such as the –CH2COOCH3 group at C9 [C10—C9—C11—C12 - 149.1 (4)° in (I) and -149.6 (2)° in DAS] and the furan ring (E) at C17 [C16—C17—C20—C22 64.5 (6)° in (I) and 63.8 (5)° in DAS], show similar conformations. \sch
Rings A and B in (I) are in chair conformations, as is evident from the ring puckering amplitudes (Cremer & Pople, 1975); QT = 0.522 (5) Å, θ = 5.8 (5)° and ϕ2 = -178 (5)°, and QT = 0.552 (4) Å, θ = 7.0 (5)° and ϕ2= -29 (4)°, respectively. Ring F is in a half-chair conformation [q2 = 0.454 (4) Å and ϕ2 = 93.6 (5)°], with atoms C4 and C5 deviating from the least-squares plane defined by atoms C6, O6 and C28 by 0.450 (5) and -0.295 (4) Å, respectively. Ring I also adopts a half-chair conformation [q2 = 0.405 (4) Å and ϕ2= 241.1 (6)°], with atoms C7 and C8 deviating from the plane defined by atoms O7, C14 and C15 by -0.214 (4) and 0.459 (4) Å, respectively, while ring D' is in an envelope conformation [q2 = 0.319 (5) Å and ϕ2 = 103.8 (8)°], with atom C16 at the apex of the envelope. Ring E adopts a planar conformation (Nardelli, 1995). The ring junctions A/B, A/F and B/F are trans-fused. The B/I junction is cis-fused, and I/D' is quasi-trans-fused due to the sp2 hybridization of C13.
The molecules in the crystal lattice of (I) are stabilized by an O—H···O hydrogen bond between atoms O3 and O6(-x, y + 1/2, 1/2 - z). This hydrogen bond links the molecules into infinite one-dimensional chains which run parallel to the y axis, and can be denoted by the graph set motif C(6) (Berstein et al., 1995). A similar pattern of hydrogen bonds was also observed in the related structure of DAS (Kabaleeswaran et al., 1999).