organic compounds
Kallolide A acetate pyrazoline
aPO Box 70377, University of Puerto Rico, San Juan, PR 00936-0377, Puerto Rico
*Correspondence e-mail: idalizrodriguez@gmail.com
In the 6,9.01,12]octadeca-6,8,14-trien-5-yl acetate], C23H28N2O5, there is a 12-membered carbon macrocyclic structure. In addition, there is a trisubstituted furan ring, an approximately planar γ-lactone ring [maximum deviation of 0.057 (3) Å] and a pyrazoline ring, the latter in an The pyrazoline and the γ-lactone rings are fused in a cis configuration. In the crystal, molecules are linked by weak C—H⋯O interactions, forming a two-dimensional network parallel to (001). An intramolecular C—H⋯O hydrogen bond is also present.
of kallolide A acetate pyrazoline [systematic name: 7-methyl-16-oxo-4,10-bis(prop-1-en-2-yl)-17,18-dioxa-14,15-diazatetracyclo[9.4.2.1Related literature
For information on West Indies sea plumes, see: Bayer (1961); Lasker & Coffroth (1983); Humman (1996); Sánchez et al. (1998); Williams & Vennam (2001). For complete background to the natural product chemistry of the Gorgonian genus Pseudopterogorgia, see: Marrero et al. (2010). For species of Pseudopterogorgia, see: Yoshioka (1997); Sánchez et al. (2003); Sánchez & Lasker (2003). For the biological activity of from Pseudopterogorgia, see: Heckrodt & Mulzer (2005). For more information on the pseudoterane-type of diterpenes, see: Bundurraga & Fenical (1982); Look et al. (1985); Williams et al. (1987b); Rodríguez & Soto (1996); Marrero et al. (2006). For bioactive diterpenes isolated from Pseudopterogorgia kallos, see: Marrero et al. (2003a,b, 2004a,b, 2005). For biosynthetic relationship studies between cembrane- and pseudopterane-type diterpenes, see: Rodríguez & Shi (1998); Yang et al. (2010); Li & Pattenden (2011). For information on gersolane-type diterpenes and biosynthetic relationship studies between cembrane- and gersolane-type diterpenes, see: Williams et al. (1987a); Rodríguez et al. (1998). For complete background to the chemistry of furanocembranoids, pseudopteranes, gersolanes and related compounds, see: Roethle & Trauner (2008). For the synthesis of kallolide A and kallolide A acetate, see: Marshall & Liao (1998).
Experimental
Crystal data
|
Refinement
|
Data collection: SMART-NT (Bruker, 1998); cell SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536811051890/wn2456sup1.cif
contains datablocks I, global. DOI:Supporting information file. DOI: 10.1107/S1600536811051890/wn2456Isup2.cdx
Structure factors: contains datablock I. DOI: 10.1107/S1600536811051890/wn2456Isup3.hkl
Supporting information file. DOI: 10.1107/S1600536811051890/wn2456Isup4.cml
Fresh specimens of the sea plume Pseudopterogorgia kallos were collected by hand using SCUBA at depths of 83–91 ft in Old Providence Island, Colombia, on March 15–16, 2002. The taxonomic identification of these gorgonian species was conducted by Dr. Juan A. Sánchez (Universidad de Los Andes, Bogotá). A voucher specimen is stored in the Chemistry Department of the University of Puerto Rico, Río Piedras Campus. The organism was partially air-dried, frozen, and lyophilized prior to its extraction. The dry specimens (1.07 kg) were blended using a mixture of CH2Cl2/MeOH (1:1) (20 x 1 L). After filtration, the crude extract was concentrated and stored under vacuum to yield a greenish gum (166 g). The crude extract was suspended in water (2 L) and extracted with n-hexane (3 x 2 L), CHCl3 (3 x 2 L), and EtOAc (2 x 2 L). Each extract was concentrated under reduced pressure to yield 71.9 g of the n-hexane extract (PkH), 39.3 g of the CHCl3 extract (PkC), and 1.47 g of the EtOAc extract (PkA). The isolation and purification of the starting material, kallolide A acetate, for the synthesis of the title compound was achieved via published procedures [Marrero et al. (2006)]. A CHCl3 solution of kallolide A acetate (15 mg) was treated with an excess of CH2N2 ether solution and stirred at room temperature. After 36 h the reaction mixture was concentrated in vacuo to remove the ether solution of CH2N2 to yield 16.7 mg of kallolide A acetate pyrazoline as a pure colorless solid (16.7 mg, 100% yield). The title compound was recrystallized by slow evaporation using hot acetone as a solvent.
H atoms were positioned geometrically, with C—H = 0.96 (CH3), 0.97 (CH2), 0.98 (methine CH) and 0.93 (aromatic CH) Å, and constrained with Uiso(H) = 1.5 Ueq(parent) for methyl H and Uiso(H) = 1.2 Ueq(parent) for all other H atoms. In the absence of strong
Friedel pairs were merged prior to final refinement.Data collection: SMART-NT (Bruker, 1998); cell
SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).C23H28N2O5 | F(000) = 880 |
Mr = 412.47 | Dx = 1.217 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 9306 reflections |
a = 10.593 (6) Å | θ = 2.3–26.7° |
b = 12.426 (7) Å | µ = 0.09 mm−1 |
c = 17.099 (10) Å | T = 298 K |
V = 2251 (2) Å3 | Block, colourless |
Z = 4 | 0.40 × 0.30 × 0.10 mm |
Bruker SMART 1K CCD diffractometer | 2583 independent reflections |
Radiation source: fine-focus sealed tube | 2160 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
ϕ and ω scans | θmax = 26.4°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a) | h = −11→13 |
Tmin = 0.966, Tmax = 0.992 | k = −15→15 |
14038 measured reflections | l = −21→21 |
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)] = 0.047 | H-atom parameters constrained |
wR(F2) = 0.118 | w = 1/[σ2(Fo2) + (0.0552P)2 + 0.3145P] where P = (Fo2 + 2Fc2)/3 |
S = 1.13 | (Δ/σ)max < 0.001 |
2583 reflections | Δρmax = 0.35 e Å−3 |
276 parameters | Δρmin = −0.23 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008a), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.061 (4) |
C23H28N2O5 | V = 2251 (2) Å3 |
Mr = 412.47 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 10.593 (6) Å | µ = 0.09 mm−1 |
b = 12.426 (7) Å | T = 298 K |
c = 17.099 (10) Å | 0.40 × 0.30 × 0.10 mm |
Bruker SMART 1K CCD diffractometer | 2583 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a) | 2160 reflections with I > 2σ(I) |
Tmin = 0.966, Tmax = 0.992 | Rint = 0.041 |
14038 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.118 | H-atom parameters constrained |
S = 1.13 | Δρmax = 0.35 e Å−3 |
2583 reflections | Δρmin = −0.23 e Å−3 |
276 parameters |
Experimental. IR(neat) νmax 3078, 2969, 2944, 2927, 1764, 1728, 1642, 1375, 1251, 1227, 907, 810 cm-1; 1H NMR (300 MHz, DMSO-d6) δ 3.10 (1H, dd, J = 11.0, 9.0 Hz, H-2),5.60 (1H, d, J = 11.7 Hz, H-2), 6.23 (1H, s, H-5), 3.89 (1H, d, J = 2.7 Hz, H-7), 4.59 (1H, m, H-8)a, 2.11 (1H, br dd, J = 6.3, 5.7 Hz, H-9), 2.48 (1H, m, H-11a)b, 0.81 (1H, dd, J = 14.1, 5.7 Hz), 1.31 (1H,m,H-12a), 0.30 (1H, dd, J = 13.8, 13.5 Hz, H-12b), 4.88 (1H,vd, J = 1.2 Hz, H-14a), 4.51 (1H, s, H-14b), 1.77 (3H, s, H-15), 2.00 (3H, s, H-16), 5.08 (1H, d, J = 2.1 Hz, H-18a), 4.93 (1H, s, H-18b), 1.63 (3H, s, H-19), 1.94 (3H, s, H-22), 5.17 (1H, d, J = 18.6 Hz, H-23a), 5.62 (1H, dd, J = 18.9 Hz, H-23b)a (a values are interchangeable, b proton signal peak overlap with solvent). 13C NMR (DMSO-d6, 75 MHz) δ 48.4 (CH, C-1), 66.5 (CH, C-2), 146.5 (C, C-3), 122.4 (C, C4), 114.4 (CH, C-5), 152.5 (C, C-6), 46.0 (CH, C-7), 84.6 (CH, C-8), 36.7 (CH, C-9), 105.7 (C, C-10), 26.6 (CH2, C-11), 25.1 (CH2, C-12), 143.9 (C, C-13), 114.4 (CH2, C-14), 21.8 (CH3, C-15), 9.7 (CH3, C-16), 143.3 (C, C-17), 115.5 (CH2, C-18), 17.9 (CH3, C-19), 172.9 (C, C-10), 170.1 (C, C-21), 21.1 (CH3, C-22), 86.2 (CH2, C-23); LREI-MS m/z [M]+; 412(6.4), 384 (19), 370 (15), 342 (9), 231 (7), 214 (13), 178 (11), 165 (23), 164 (100), 163 (87), 135 (28); HREI-MS m/z [M]+ calcd for C23H28N2O5 412.1998 found 412.2003. |
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 | ||
O2 | 0.85009 (16) | 0.35559 (14) | 0.16945 (10) | 0.0506 (4) | |
O1 | 0.59698 (18) | 0.25015 (14) | 0.22854 (11) | 0.0564 (5) | |
C3 | 0.7288 (2) | 0.39670 (19) | 0.17940 (15) | 0.0474 (6) | |
C9 | 1.0882 (3) | 0.4597 (2) | 0.24459 (17) | 0.0586 (7) | |
H9 | 1.0151 | 0.5047 | 0.2316 | 0.070* | |
O5 | 0.4266 (2) | 0.3406 (2) | 0.1863 (2) | 0.1156 (11) | |
O3 | 1.0951 (2) | 0.27160 (17) | 0.20733 (13) | 0.0696 (6) | |
C20 | 1.0579 (3) | 0.2727 (2) | 0.28330 (18) | 0.0629 (8) | |
C11 | 0.9562 (3) | 0.4146 (2) | 0.37422 (16) | 0.0629 (8) | |
H11A | 0.9813 | 0.4790 | 0.4023 | 0.076* | |
H11B | 0.9513 | 0.3568 | 0.4122 | 0.076* | |
O4 | 1.0311 (3) | 0.19117 (16) | 0.31793 (15) | 0.0867 (8) | |
C6 | 0.9085 (3) | 0.4155 (2) | 0.11168 (14) | 0.0526 (6) | |
C2 | 0.6586 (3) | 0.35346 (19) | 0.24830 (14) | 0.0486 (6) | |
H2 | 0.5943 | 0.4056 | 0.2645 | 0.058* | |
C1 | 0.7473 (3) | 0.3298 (2) | 0.31789 (14) | 0.0517 (6) | |
H1 | 0.8090 | 0.2763 | 0.3003 | 0.062* | |
C10 | 1.0619 (3) | 0.3868 (2) | 0.31621 (17) | 0.0576 (7) | |
N2 | 1.2578 (3) | 0.4666 (3) | 0.3389 (2) | 0.0925 (10) | |
C12 | 0.8225 (3) | 0.4334 (2) | 0.34163 (15) | 0.0553 (7) | |
H12A | 0.8291 | 0.4796 | 0.2961 | 0.066* | |
H12B | 0.7739 | 0.4720 | 0.3807 | 0.066* | |
C4 | 0.7090 (3) | 0.4796 (2) | 0.12735 (14) | 0.0555 (7) | |
C5 | 0.8259 (3) | 0.4905 (2) | 0.08522 (15) | 0.0620 (8) | |
H5 | 0.8421 | 0.5407 | 0.0462 | 0.074* | |
C8 | 1.1207 (3) | 0.3803 (3) | 0.17747 (19) | 0.0647 (8) | |
H8 | 1.2113 | 0.3859 | 0.1667 | 0.078* | |
N1 | 1.1882 (3) | 0.3930 (2) | 0.36229 (18) | 0.0823 (9) | |
C7 | 1.0488 (3) | 0.3979 (3) | 0.09993 (17) | 0.0652 (8) | |
H7 | 1.0808 | 0.4662 | 0.0792 | 0.078* | |
C23 | 1.2011 (3) | 0.5276 (3) | 0.2723 (2) | 0.0832 (10) | |
H23A | 1.2621 | 0.5365 | 0.2305 | 0.100* | |
H23B | 1.1733 | 0.5982 | 0.2894 | 0.100* | |
C21 | 0.4806 (3) | 0.2569 (3) | 0.19643 (19) | 0.0699 (8) | |
C13 | 0.6784 (3) | 0.2824 (2) | 0.38899 (16) | 0.0685 (9) | |
C16 | 0.5932 (4) | 0.5490 (3) | 0.1176 (2) | 0.0900 (12) | |
H16A | 0.5250 | 0.5194 | 0.1477 | 0.135* | |
H16B | 0.5697 | 0.5511 | 0.0634 | 0.135* | |
H16C | 0.6111 | 0.6206 | 0.1354 | 0.135* | |
C15 | 0.5551 (4) | 0.3321 (3) | 0.41338 (19) | 0.0872 (11) | |
H15A | 0.4911 | 0.3143 | 0.3758 | 0.131* | |
H15B | 0.5643 | 0.4089 | 0.4161 | 0.131* | |
H15C | 0.5312 | 0.3049 | 0.4638 | 0.131* | |
C22 | 0.4304 (4) | 0.1483 (3) | 0.1731 (2) | 0.0971 (13) | |
H22A | 0.3673 | 0.1257 | 0.2099 | 0.146* | |
H22B | 0.4982 | 0.0970 | 0.1725 | 0.146* | |
H22C | 0.3936 | 0.1528 | 0.1219 | 0.146* | |
C17 | 1.0837 (4) | 0.3138 (4) | 0.03873 (19) | 0.0848 (11) | |
C19 | 1.0205 (7) | 0.2132 (4) | 0.0357 (3) | 0.135 (2) | |
H19A | 1.0489 | 0.1736 | −0.0092 | 0.202* | |
H19B | 0.9311 | 0.2249 | 0.0319 | 0.202* | |
H19C | 1.0387 | 0.1730 | 0.0823 | 0.202* | |
C14 | 0.7312 (5) | 0.2005 (3) | 0.4285 (2) | 0.1048 (14) | |
H14A | 0.6914 | 0.1727 | 0.4725 | 0.126* | |
H14B | 0.8076 | 0.1716 | 0.4118 | 0.126* | |
C18 | 1.1806 (6) | 0.3379 (6) | −0.0128 (3) | 0.191 (3) | |
H18A | 1.2052 | 0.2878 | −0.0502 | 0.229* | |
H18B | 1.2210 | 0.4043 | −0.0100 | 0.229* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O2 | 0.0472 (9) | 0.0503 (9) | 0.0543 (10) | 0.0012 (8) | −0.0055 (8) | 0.0105 (8) |
O1 | 0.0550 (11) | 0.0550 (10) | 0.0590 (10) | −0.0065 (9) | −0.0097 (9) | 0.0015 (8) |
C3 | 0.0486 (13) | 0.0441 (12) | 0.0495 (13) | 0.0021 (11) | −0.0095 (11) | −0.0005 (11) |
C9 | 0.0533 (15) | 0.0518 (14) | 0.0706 (16) | −0.0075 (13) | −0.0157 (14) | 0.0067 (13) |
O5 | 0.0589 (14) | 0.0964 (19) | 0.192 (3) | 0.0018 (14) | −0.0418 (19) | −0.001 (2) |
O3 | 0.0711 (13) | 0.0584 (12) | 0.0792 (14) | 0.0083 (11) | −0.0173 (12) | −0.0034 (10) |
C20 | 0.0616 (18) | 0.0524 (16) | 0.0748 (19) | 0.0048 (14) | −0.0254 (15) | 0.0057 (14) |
C11 | 0.083 (2) | 0.0551 (16) | 0.0502 (14) | −0.0120 (15) | −0.0210 (14) | 0.0033 (13) |
O4 | 0.1109 (19) | 0.0470 (11) | 0.1021 (16) | −0.0006 (12) | −0.0299 (15) | 0.0179 (11) |
C6 | 0.0571 (15) | 0.0547 (14) | 0.0460 (13) | −0.0065 (13) | −0.0059 (12) | 0.0063 (12) |
C2 | 0.0500 (13) | 0.0472 (12) | 0.0488 (13) | −0.0001 (12) | −0.0041 (11) | −0.0012 (11) |
C1 | 0.0610 (15) | 0.0471 (13) | 0.0469 (13) | −0.0039 (12) | −0.0069 (12) | 0.0030 (11) |
C10 | 0.0609 (16) | 0.0500 (14) | 0.0620 (16) | −0.0036 (12) | −0.0251 (14) | 0.0059 (12) |
N2 | 0.078 (2) | 0.090 (2) | 0.109 (2) | −0.0219 (18) | −0.0372 (18) | 0.0025 (18) |
C12 | 0.0708 (18) | 0.0495 (14) | 0.0457 (12) | −0.0050 (13) | −0.0063 (13) | 0.0004 (11) |
C4 | 0.0660 (17) | 0.0563 (14) | 0.0443 (12) | 0.0099 (14) | −0.0104 (12) | 0.0017 (11) |
C5 | 0.081 (2) | 0.0597 (16) | 0.0455 (13) | −0.0025 (16) | −0.0075 (14) | 0.0129 (12) |
C8 | 0.0509 (15) | 0.0694 (18) | 0.0738 (19) | −0.0056 (14) | −0.0058 (14) | 0.0060 (15) |
N1 | 0.0778 (19) | 0.0810 (18) | 0.0882 (19) | −0.0025 (16) | −0.0410 (16) | 0.0061 (16) |
C7 | 0.0586 (17) | 0.0775 (19) | 0.0594 (16) | −0.0087 (15) | −0.0001 (13) | 0.0094 (15) |
C23 | 0.076 (2) | 0.0747 (19) | 0.099 (2) | −0.0248 (19) | −0.024 (2) | 0.0073 (19) |
C21 | 0.0514 (16) | 0.082 (2) | 0.0764 (19) | −0.0127 (16) | −0.0093 (15) | 0.0080 (17) |
C13 | 0.086 (2) | 0.0729 (18) | 0.0464 (14) | −0.0235 (18) | −0.0050 (15) | 0.0042 (14) |
C16 | 0.104 (3) | 0.089 (2) | 0.077 (2) | 0.043 (2) | −0.007 (2) | 0.0167 (19) |
C15 | 0.094 (3) | 0.106 (3) | 0.0609 (18) | −0.026 (2) | 0.0143 (18) | −0.0068 (18) |
C22 | 0.092 (3) | 0.099 (3) | 0.101 (3) | −0.040 (2) | −0.030 (2) | 0.010 (2) |
C17 | 0.069 (2) | 0.123 (3) | 0.0621 (18) | 0.005 (2) | 0.0067 (17) | −0.0059 (19) |
C19 | 0.178 (6) | 0.116 (4) | 0.110 (3) | −0.003 (4) | 0.035 (4) | −0.032 (3) |
C14 | 0.131 (4) | 0.107 (3) | 0.076 (2) | −0.023 (3) | −0.009 (2) | 0.041 (2) |
C18 | 0.154 (5) | 0.275 (8) | 0.143 (5) | −0.080 (6) | 0.086 (4) | −0.082 (5) |
O2—C6 | 1.383 (3) | C4—C5 | 1.439 (4) |
O2—C3 | 1.393 (3) | C4—C16 | 1.509 (4) |
O1—C21 | 1.353 (4) | C5—H5 | 0.9300 |
O1—C2 | 1.479 (3) | C8—C7 | 1.545 (4) |
C3—C4 | 1.378 (4) | C8—H8 | 0.9800 |
C3—C2 | 1.493 (4) | C7—C17 | 1.524 (5) |
C9—C23 | 1.539 (4) | C7—H7 | 0.9800 |
C9—C10 | 1.549 (4) | C23—H23A | 0.9700 |
C9—C8 | 1.552 (4) | C23—H23B | 0.9700 |
C9—H9 | 0.9800 | C21—C22 | 1.505 (5) |
O5—C21 | 1.200 (4) | C13—C14 | 1.343 (5) |
O3—C20 | 1.358 (4) | C13—C15 | 1.504 (5) |
O3—C8 | 1.470 (4) | C16—H16A | 0.9600 |
C20—O4 | 1.207 (4) | C16—H16B | 0.9600 |
C20—C10 | 1.526 (4) | C16—H16C | 0.9600 |
C11—C10 | 1.535 (5) | C15—H15A | 0.9600 |
C11—C12 | 1.540 (4) | C15—H15B | 0.9600 |
C11—H11A | 0.9700 | C15—H15C | 0.9600 |
C11—H11B | 0.9700 | C22—H22A | 0.9600 |
C6—C5 | 1.356 (4) | C22—H22B | 0.9600 |
C6—C7 | 1.516 (4) | C22—H22C | 0.9600 |
C2—C1 | 1.544 (3) | C17—C18 | 1.386 (6) |
C2—H2 | 0.9800 | C17—C19 | 1.419 (6) |
C1—C13 | 1.536 (4) | C19—H19A | 0.9600 |
C1—C12 | 1.567 (4) | C19—H19B | 0.9600 |
C1—H1 | 0.9800 | C19—H19C | 0.9600 |
C10—N1 | 1.555 (4) | C14—H14A | 0.9300 |
N2—N1 | 1.241 (4) | C14—H14B | 0.9300 |
N2—C23 | 1.493 (5) | C18—H18A | 0.9300 |
C12—H12A | 0.9700 | C18—H18B | 0.9300 |
C12—H12B | 0.9700 | ||
C6—O2—C3 | 107.6 (2) | C7—C8—C9 | 115.8 (2) |
C21—O1—C2 | 116.2 (2) | O3—C8—H8 | 108.2 |
C4—C3—O2 | 109.6 (2) | C7—C8—H8 | 108.2 |
C4—C3—C2 | 134.7 (2) | C9—C8—H8 | 108.2 |
O2—C3—C2 | 115.1 (2) | N2—N1—C10 | 112.6 (3) |
C23—C9—C10 | 102.5 (2) | C6—C7—C17 | 115.3 (3) |
C23—C9—C8 | 113.8 (3) | C6—C7—C8 | 113.0 (2) |
C10—C9—C8 | 104.7 (2) | C17—C7—C8 | 111.9 (3) |
C23—C9—H9 | 111.7 | C6—C7—H7 | 105.2 |
C10—C9—H9 | 111.7 | C17—C7—H7 | 105.2 |
C8—C9—H9 | 111.7 | C8—C7—H7 | 105.2 |
C20—O3—C8 | 112.1 (2) | N2—C23—C9 | 105.6 (2) |
O4—C20—O3 | 122.0 (3) | N2—C23—H23A | 110.6 |
O4—C20—C10 | 127.3 (3) | C9—C23—H23A | 110.6 |
O3—C20—C10 | 110.7 (3) | N2—C23—H23B | 110.6 |
C10—C11—C12 | 118.1 (2) | C9—C23—H23B | 110.6 |
C10—C11—H11A | 107.8 | H23A—C23—H23B | 108.8 |
C12—C11—H11A | 107.8 | O5—C21—O1 | 123.1 (3) |
C10—C11—H11B | 107.8 | O5—C21—C22 | 124.9 (3) |
C12—C11—H11B | 107.8 | O1—C21—C22 | 112.0 (3) |
H11A—C11—H11B | 107.1 | C14—C13—C15 | 122.3 (3) |
C5—C6—O2 | 108.6 (2) | C14—C13—C1 | 119.4 (3) |
C5—C6—C7 | 133.5 (3) | C15—C13—C1 | 118.3 (3) |
O2—C6—C7 | 117.1 (2) | C4—C16—H16A | 109.5 |
O1—C2—C3 | 110.6 (2) | C4—C16—H16B | 109.5 |
O1—C2—C1 | 106.24 (18) | H16A—C16—H16B | 109.5 |
C3—C2—C1 | 111.9 (2) | C4—C16—H16C | 109.5 |
O1—C2—H2 | 109.3 | H16A—C16—H16C | 109.5 |
C3—C2—H2 | 109.3 | H16B—C16—H16C | 109.5 |
C1—C2—H2 | 109.3 | C13—C15—H15A | 109.5 |
C13—C1—C2 | 113.2 (2) | C13—C15—H15B | 109.5 |
C13—C1—C12 | 110.6 (2) | H15A—C15—H15B | 109.5 |
C2—C1—C12 | 110.7 (2) | C13—C15—H15C | 109.5 |
C13—C1—H1 | 107.4 | H15A—C15—H15C | 109.5 |
C2—C1—H1 | 107.4 | H15B—C15—H15C | 109.5 |
C12—C1—H1 | 107.4 | C21—C22—H22A | 109.5 |
C20—C10—C11 | 115.3 (3) | C21—C22—H22B | 109.5 |
C20—C10—C9 | 104.9 (2) | H22A—C22—H22B | 109.5 |
C11—C10—C9 | 120.7 (2) | C21—C22—H22C | 109.5 |
C20—C10—N1 | 104.9 (2) | H22A—C22—H22C | 109.5 |
C11—C10—N1 | 106.8 (2) | H22B—C22—H22C | 109.5 |
C9—C10—N1 | 102.5 (2) | C18—C17—C19 | 121.1 (5) |
N1—N2—C23 | 112.4 (3) | C18—C17—C7 | 117.9 (5) |
C11—C12—C1 | 115.9 (2) | C19—C17—C7 | 121.0 (3) |
C11—C12—H12A | 108.3 | C17—C19—H19A | 109.5 |
C1—C12—H12A | 108.3 | C17—C19—H19B | 109.5 |
C11—C12—H12B | 108.3 | H19A—C19—H19B | 109.5 |
C1—C12—H12B | 108.3 | C17—C19—H19C | 109.5 |
H12A—C12—H12B | 107.4 | H19A—C19—H19C | 109.5 |
C3—C4—C5 | 105.2 (2) | H19B—C19—H19C | 109.5 |
C3—C4—C16 | 128.5 (3) | C13—C14—H14A | 120.0 |
C5—C4—C16 | 126.2 (3) | C13—C14—H14B | 120.0 |
C6—C5—C4 | 108.9 (2) | H14A—C14—H14B | 120.0 |
C6—C5—H5 | 125.5 | C17—C18—H18A | 120.0 |
C4—C5—H5 | 125.5 | C17—C18—H18B | 120.0 |
O3—C8—C7 | 109.7 (2) | H18A—C18—H18B | 120.0 |
O3—C8—C9 | 106.6 (2) | ||
C6—O2—C3—C4 | 1.6 (3) | C2—C3—C4—C16 | −8.9 (5) |
C6—O2—C3—C2 | −170.6 (2) | O2—C6—C5—C4 | 0.2 (3) |
C8—O3—C20—O4 | 179.1 (3) | C7—C6—C5—C4 | −168.9 (3) |
C8—O3—C20—C10 | −3.5 (3) | C3—C4—C5—C6 | 0.7 (3) |
C3—O2—C6—C5 | −1.1 (3) | C16—C4—C5—C6 | 178.4 (3) |
C3—O2—C6—C7 | 170.1 (2) | C20—O3—C8—C7 | −129.1 (3) |
C21—O1—C2—C3 | −87.0 (3) | C20—O3—C8—C9 | −2.9 (3) |
C21—O1—C2—C1 | 151.3 (2) | C23—C9—C8—O3 | 119.0 (3) |
C4—C3—C2—O1 | 106.3 (3) | C10—C9—C8—O3 | 7.9 (3) |
O2—C3—C2—O1 | −84.0 (2) | C23—C9—C8—C7 | −118.6 (3) |
C4—C3—C2—C1 | −135.4 (3) | C10—C9—C8—C7 | 130.2 (3) |
O2—C3—C2—C1 | 34.2 (3) | C23—N2—N1—C10 | −0.7 (4) |
O1—C2—C1—C13 | −57.6 (3) | C20—C10—N1—N2 | 122.8 (3) |
C3—C2—C1—C13 | −178.4 (2) | C11—C10—N1—N2 | −114.3 (3) |
O1—C2—C1—C12 | 177.6 (2) | C9—C10—N1—N2 | 13.5 (4) |
C3—C2—C1—C12 | 56.7 (3) | C5—C6—C7—C17 | −99.1 (4) |
O4—C20—C10—C11 | −39.2 (4) | O2—C6—C7—C17 | 92.5 (3) |
O3—C20—C10—C11 | 143.7 (2) | C5—C6—C7—C8 | 130.4 (3) |
O4—C20—C10—C9 | −174.4 (3) | O2—C6—C7—C8 | −38.0 (4) |
O3—C20—C10—C9 | 8.4 (3) | O3—C8—C7—C6 | 74.9 (3) |
O4—C20—C10—N1 | 78.0 (4) | C9—C8—C7—C6 | −45.8 (4) |
O3—C20—C10—N1 | −99.2 (3) | O3—C8—C7—C17 | −57.2 (3) |
C12—C11—C10—C20 | −74.1 (3) | C9—C8—C7—C17 | −178.0 (3) |
C12—C11—C10—C9 | 53.6 (3) | N1—N2—C23—C9 | −12.6 (4) |
C12—C11—C10—N1 | 169.9 (2) | C10—C9—C23—N2 | 19.6 (3) |
C23—C9—C10—C20 | −128.7 (3) | C8—C9—C23—N2 | −92.8 (3) |
C8—C9—C10—C20 | −9.6 (3) | C2—O1—C21—O5 | −2.4 (5) |
C23—C9—C10—C11 | 99.1 (3) | C2—O1—C21—C22 | 175.7 (3) |
C8—C9—C10—C11 | −141.8 (2) | C2—C1—C13—C14 | 137.6 (3) |
C23—C9—C10—N1 | −19.3 (3) | C12—C1—C13—C14 | −97.6 (3) |
C8—C9—C10—N1 | 99.8 (2) | C2—C1—C13—C15 | −44.3 (3) |
C10—C11—C12—C1 | 76.3 (3) | C12—C1—C13—C15 | 80.6 (3) |
C13—C1—C12—C11 | 85.8 (3) | C6—C7—C17—C18 | 136.5 (5) |
C2—C1—C12—C11 | −147.9 (2) | C8—C7—C17—C18 | −92.6 (5) |
O2—C3—C4—C5 | −1.4 (3) | C6—C7—C17—C19 | −44.7 (5) |
C2—C3—C4—C5 | 168.6 (3) | C8—C7—C17—C19 | 86.2 (5) |
O2—C3—C4—C16 | −178.9 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8···O5i | 0.98 | 2.37 | 3.281 (4) | 154 |
C9—H9···O4ii | 0.98 | 2.52 | 3.319 (4) | 139 |
C16—H16A···O5 | 0.96 | 2.54 | 3.347 (5) | 142 |
Symmetry codes: (i) x+1, y, z; (ii) −x+2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C23H28N2O5 |
Mr | 412.47 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 298 |
a, b, c (Å) | 10.593 (6), 12.426 (7), 17.099 (10) |
V (Å3) | 2251 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.40 × 0.30 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART 1K CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2008a) |
Tmin, Tmax | 0.966, 0.992 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14038, 2583, 2160 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.626 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.118, 1.13 |
No. of reflections | 2583 |
No. of parameters | 276 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.35, −0.23 |
Computer programs: SMART-NT (Bruker, 1998), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008b), SHELXL97 (Sheldrick, 2008b), SHELXTL (Sheldrick, 2008b).
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8···O5i | 0.98 | 2.37 | 3.281 (4) | 153.9 |
C9—H9···O4ii | 0.98 | 2.52 | 3.319 (4) | 139.1 |
C16—H16A···O5 | 0.96 | 2.54 | 3.347 (5) | 141.5 |
Symmetry codes: (i) x+1, y, z; (ii) −x+2, y+1/2, −z+1/2. |
Acknowledgements
Support for this research was kindly provided by the NIH–MBRS Program and the DEGI at the University of Puerto Rico. The authors thank Dr Raphael G. Raptis for the use of the X-ray facilities and Dr Hong Zhao for her help with the data collection and initial structure refinement.
References
Bayer, F. M. (1961). The Shallow-Water Octocorallia of the West Indian Region. The Hague: Martinus Nijhof. Google Scholar
Bruker (1998). SMART-NT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bundurraga, M. M. & Fenical, W. (1982). J. Am. Chem. Soc. 104, 6463–6465. Google Scholar
Heckrodt, T. J. & Mulzer, J. (2005). Top. Curr. Chem. 244, 1–41. CAS Google Scholar
Humman, P. (1996). Reef Coral Identification, edited by N. Deloach, pp. 50–53. Jacksonville: New World Publications. Google Scholar
Lasker, H. R. & Coffroth, M. A. (1983). Mar. Ecol. Prog. Ser. 13, 21–28. CrossRef Web of Science Google Scholar
Li, Y. & Pattenden, G. (2011). Tetrahedron Lett. 52, 31150–3319. Google Scholar
Look, S. A., Burch, M. T., Fenical, W., Qi-tai, Z. & Clardy, J. (1985). J. Org. Chem. 50, 5741–5746. CSD CrossRef CAS Web of Science Google Scholar
Marrero, J., Ospina, C. A., Rodríguez, A. D., Baran, P., Zhao, H., Franzblau, S. G. & Ortega-Barria, E. (2006). Tetrahedron, 62, 6998–7008. Web of Science CSD CrossRef CAS Google Scholar
Marrero, J., Rodríguez, A. D., Baran, P. & Raptis, R. G. (2003a). J. Org. Chem. 68, 4977–4979. Web of Science CSD CrossRef PubMed CAS Google Scholar
Marrero, J., Rodríguez, A. D., Baran, P. & Raptis, R. G. (2003b). Org. Lett. 5, 2551-2554. Web of Science CSD CrossRef PubMed CAS Google Scholar
Marrero, J., Rodríguez, A. D., Baran, P. & Raptis, R. G. (2004a). Eur. J. Org. Chem. pp. 3909–3912. Web of Science CSD CrossRef Google Scholar
Marrero, J., Rodríguez, A. D., Baran, P., Raptis, R. G., Sánchez, J. A., Ortega-Barria, E. & Capson, T. L. (2004b). Org. Lett. 6, 1661–1664. Web of Science CSD CrossRef PubMed CAS Google Scholar
Marrero, J., Rodríguez, A. D. & Barnes, C. L. (2005). Org. Lett. 7, 1877–1880. Web of Science CSD CrossRef PubMed CAS Google Scholar
Marrero, J., Rodríguez, I. I. & Rodríguez, A. D. (2010). Comprehensive Natural Products II, Chemistry and Biology, vol. 2, pp. 363–429. Google Scholar
Marshall, J. A. & Liao, J. (1998). J. Org. Chem. 63, 5962–5970. Web of Science CrossRef PubMed CAS Google Scholar
Rodríguez, A. D. & Shi, J.-G. (1998). J. Org. Chem. 63, 420–421. PubMed Google Scholar
Rodríguez, A. D., Shi, J.-G. & Huang, S. D. (1998). J. Org. Chem. 63, 4425–4432. Google Scholar
Rodríguez, A. D. & Soto, J. J. (1996). Chem. Pharm. Bull. 44, 91–94. PubMed Web of Science Google Scholar
Roethle, P. A. & Trauner, D. (2008). Nat. Prod. Rep. 25, 298–317. Web of Science CrossRef PubMed CAS Google Scholar
Sánchez, J. A. & Lasker, H. R. (2003). Proc. R. Soc. Lond. B, 270, 2039–2044. Google Scholar
Sánchez, J. A., McFadden, C. S., France, S. C. & Lasker, H. R. (2003). Mar. Biol. 142, 975–987. Google Scholar
Sánchez, J. A., Zea, S. & Díaz, J. M. (1998). Caribb. J. Sci. 34, 250–264. Google Scholar
Sheldrick, G. M. (2008a). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008b). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Williams, D., Andersen, R. J., Parkanyi, L. & Clardy, J. (1987a). Tetrahedron Lett. 28, 5079–5080. CSD CrossRef CAS Web of Science Google Scholar
Williams, D., Andersen, R. J., van Duyne, G. D. & Clardy, J. (1987b). J. Org. Chem. 52, 332–335. CSD CrossRef CAS Web of Science Google Scholar
Williams, G. C. & Vennam, J. S. (2001). Bull. Biol. Soc. Wash. 10, 71–95. Google Scholar
Yang, Z., Li, Y. & Pattenden, G. (2010). Tetrahedron, 66, 6546–6549. Web of Science CrossRef CAS Google Scholar
Yoshioka, P. M. (1997). J. Exp. Mar. Biol. Ecol. 214, 167–178. CrossRef Web of Science Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound, in its enantiopure form, was prepared from the known pseudopterane diterpene kallolide A acetate, which was isolated from the marine sea plume Pseudoptereogorgia kallos.
The gorgonian octocorals of the genus Pseudopterogorgia are common inhabitants of tropical West Indies (Humman, 1996) and Indo-Pacific reefs. They can be adapted to different marine reef environments, from shallow to clear deep waters. Twenty two species and subspecies of Pseudopterogorgia have been reported and are commonly known as sea plumes for the feather-like appearance of their branches and ramifications (Bayer, 1961; Marrero et al., 2010). Despite these general morphological similarities each species can be identified by differences in color, branch ramification, polyps size, texture, growth form, mucus production, sclerites, spicule, and geographical distribution (Yoshioka, 1997; Sánchez et al., 2003; Sánchez & Lasker, 2003). In the West Indies region, sea plumes from this genus are commonly found from Bermuda to the Bahamas, the Florida Keys, the Greater and Lesser Antilles, and the northern coast of South America to Brazil (Bayer, 1961; Williams & Vennam, 2001; Lasker & Coffroth, 1983; Sánchez et al., 1998). West Indies Pseudopterogorgia species are well known for the production of a variety of diterpenoids of fascinating molecular structures (Marrero et al., 2010) that exhibit a wide spectrum of biological activities including antibacterial, anti-inflammatory, antimalarial, and cytotoxic properties (Heckrodt & Mulzer, 2005). An early investigation on the chemical composition of Pseudopterogorgia kallos showed that it is a rich source of pseudopterane-type diterpenoids (Look et al., 1985). However, during the last eight years (2003–2011) subsequent chemical scrutiny has demonstrated that this gorgonian species also contains a number of minor bioactive diterpenes that are based on distinctively novel carbon frameworks (i.e., bielschowskysin, ciereszkolide, intricarene, kallosin A, and providencin) (Marrero et al., 2003a; Marrero et al., 2003b; Marrero et al., 2004a; Marrero et al., 2004b; Marrero et al., 2005).
The molecular structure of kallolide A acetate pyrazoline is shown in Fig. 1. It has a twelve carbon-membered macrocyclic structure with three additional rings: a trisubstituted furan, an approximately planar γ-lactone ring twisted on the C9—C10 bond, and a pyrazoline ring in an envelope conformation with C9 as the flap atom. Fused in a cis configuration, the angle between the mean planes of the pyrazoline and the γ-lactone rings is 111.5 (1)°.
In the crystal structure (Fig. 3), molecules are linked via C8— H8···O5 and C9— H9···O4 hydrogen bonds, forming a two-dimensional network. An additional intramolecular C16— H16A···O5 hydrogen bond is also present. The absolute structure was assigned as (1S, 2S, 7R, 8R, 9R, 10S), based on previous asymmetric synthesis of kallolide A and kallolide A acetate (Marshall & Liao,1998).