Volume 5. Issue 6. Pages 841-992. 2010 ISSN 1934-578X (printed); ISSN 1555-9475 (online) www.naturalproduct.us
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EDITOR-IN-CHIEF DR. PAWAN K AGRAWAL Natural Product Inc. 7963, Anderson Park Lane, Westerville, Ohio 43081, USA
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2010 Vol. 5 No. 6 849 - 850
Natural Product Communications
New Sesquiterpene Lactone and Other Constituents from Centaurea sulphurea (Asteraceae) Hichem Lakhala, Tarek Boudiara, Ahmed Kabouchea, Zahia Kabouchea*, Rachid Touzanib and Christian Bruneauc a
Laboratoire d’Obtention de Substances Thérapeutiques (L.O.S.T), Faculté des sciences, Université Mentouri - Constantine, Campus Chaabat Ersas, 25000 Constantine, Algeria
b
Université Mohamed 5, Faculté pluridisciplinaire, Nador, Morocco
c
Université de Rennes1, Institut des Sciences Chimiques de Rennes Campus de Beaulieu Avenue du général Leclerc 35000 Rennes cedex, France
[email protected]
Received: September 24th, 2009; Accepted: March 27th, 2010
Five known flavonoids (1-5) and three sesquiterpene lactones (6-8) are reported for the first time from the endemic species Centaurea sulphurea Willd. (Asteraceae). Compound 7 is a new heliangolide (6R, 7R, 8S, 3’R)-8α-(3’,4’-dihydroxymethylene-2’-butanoyloxy)-15-oxo-helianga-1(10), 4(5), 11(13)-trien-6,12-olide, named as sulphurein. Keywords: Centaurea sulphurea, Asteraceae, sesquiterpene lactones, flavonoids.
The genus Centaurea (Asteraceae), comprises more than 500 species, predominantly distributed around the Mediterranean area and western Asia [1]. Flavonoids and sesquiterpene lactones have a wide occurrence in this genus [2a-2g]. From C. sulphurea Willd., the flavone, pectolinarigenin, and the sesquiterpene lactone, cnicin, have been reported [2b]. We report here the isolation of a new sesquiterpene lactone (sulphureidin), in addition to two known sesquiterpene lactones, and five known flavonoids, cirsilineol (1), jaceosidin (2), 3 -O-methyleupatorin (3), nepetin (4), and eupatilin (5), from the aerial parts of C. sulphurea from Algeria. Compound 7, [M+H]+ at m/z 377, C20H24O7, exhibited absorption bands typical of hydroxyl (3390 cm-1) and carbonyl groups at 1765 cm-1 (C=O, γ-lactone), 1715 cm-1 (C=O, aldehyde), and 1705 cm-1 (C=O, side chain) in the IR spectrum. The heliangolide-type skeleton is evident from the chemical shift values and coupling constants of H-5 (δ 6.26, d, J = 10.5 Hz) , H-6 (δ 4.97, br d, J = 10.4 Hz), H-7 (δ 3.15, dd, J = 1.5 and 10.7 Hz) , H-13a (δ 6.37, d, J = 1.5 Hz), and H-13b (δ 5.80, d, J = 1.5 Hz). The H1→ H2→ H3 and the H5 →H6→ H7 →H8→ H9 spin system were identified by the COSY experiments and these fragments were, together with C4 and C10, combined by correlations observed in the HMBC spectrum, to form a 10-membered cyclic ring. One singlet appearing at δ 9.44 has been assigned to an
OH
O O
O
H
O O
7
OH
O
OH
O
OAc
OH
O O
8
aldehyde proton. The chemical shift of H-5 indicated that the formyl group was at C-15, which was confirmed by HMBC experiment. NOESY correlations between H1, H5, and H15 confirmed their α-position and thus the E-configuration of the C4-C5 double bond. The presence of an R-methylene-γ -lactone moiety was confirmed by the 13C NMR signals at δ: 132.8 (C-11), 169.2 (C-12) and 129.9 (C-13). The 1,2-trans-diaxial relationship between H7 and H8 was evident from their large coupling constant. The relative configuration of C8 was established by analysis of 1H coupling patterns and the NOESY cross peaks of H1 and H5, as well as the E-configuration of C1-C10 double bond. Compound 7 showed a C5H7O4 side-chain [M C5H7O4]+; m/z 245, corresponding to a 3,4-dihydroxy-2methylenebutanoyl group, exhibiting the following characteristic signals in the 1H NMR spectrum δ 6.33 (s), 6.02 (s), 4.45 (br. dd, J = 3.46 and 7.0 Hz), 3.72 (dd, J = 3.5 and 11.0 Hz) and 3.50 (dd, J = 7.0 and 11.0 Hz) respectively assigned to H-5'a, H-5’b, H-3', H-4'a, and H-4'b. The coupling constants involving H-8 indicated
850 Natural Product Communications Vol. 5 (6) 2010
that the ester side chain was α-orientated and, on the basis of NOE interactions between H-3′/H-5′b, the relative stereochemistry of the side chain is as shown in the structure below. The negative optical rotation of a compound with a related 6R,7R,8S configuration led to the assignment of (6R,7R,8S,3’R)-8α-(3',4’-dihydroxymethylene-2’-butanoyloxy)-15-oxo helianga-1(10),4(5), 11(13)-trien-6,12-olide to 7. To the best of our knowledge, this is first time that this compound has been reported from a natural source, but it has been semi-synthesized starting from cnicin [3a]. Spectral data of compound 8 were similar to those of compound 7, but bearing an acetoxy group instead of the formyl group at C-4. Compound 8 was thus identified as (6R,7R,8S,3’R)-8α-(3’,4’-dihydroxymethylene-2’-butanoyloxy)-15-acetoxy-helianga-1(10), 4(5),11(13)-trien-6,12-olide [3b].
Experimental General: Melting points, Buchi B-540; IR, Bruker IFS55 spectrophotometer; NMR, Bruker AMX-400 spectrometer; MS, and HRE-IMS on a Micromass model Autospec (70 eV) spectrometer. Plant material: Aerial parts of Centaurea sulphurea Willd. were collected in May 2007 at Batna (eastern Algeria). The voucher specimen (LOST Cs/05/07) was identified by Professor Gérard De Bélair (University Badji-Mokhtar, Annaba). Extraction and isolation: The air dried powdered aerial parts of C. sulphurea (1 Kg) were extracted in a Soxhlet apparatus with CHCl3. The residue (7.5 g) was column chromatographed on silica gel eluted with cyclohexane and CH2Cl2 (fractions 1-90) then with CH2Cl2/EtOAc (fractions 91-130) and finally with EtOAc/MeOH (fractions 131-166), with increasing polarity. Compounds 1-5 where found in fractions 1-90 and fractions 91-130. TLC purification on silica gel, eluted
Lakhal et al.
with CH2Cl2–MeOH (9:1), furnished cirsilineol (1) (35 mg), jaceosidin (2) (28 mg), 3′-O-methyleupatorin (3) (30 mg), nepetin (4) (18 mg) and eupatilin (5) (35 mg). Fractions 95-115 (500 mg) were combined and column chromatographed over silica gel using CHCl3–EtOAc mixtures of increasing polarity furnishing 6 [3c] (100 mg). Repeated CC over silica gel using CH2Cl2-MeOH mixtures yielded 7 (30 mg) and 8 (20 mg). Sulphurein (7) Amorphous solid. [α]D25: - 57.4 (c 0.1, CHCl3). IR (KBr, ν cm-1): 3390, 2930, 2870, 1765, 1715, 1705, 1682, 1266, 1445, 11195, 1068, 1012, 975. 1 H NMR (CDCl3, 400 MHz): 1.88 (3H, s, H-14), 1.93 (1H, m, H-2b), 2.16 (1H, ddd, J = 4.1, 12.8, 13.0 Hz, H3b), 2.36 (1H, dd, J = 11.7, 12.0 Hz, H-9b), 2. 50 (1H, m, H-2a), 2.64 (1H, dd, J = 3.5, 12.0 Hz, H-9a), 2.76 (1H, ddd, J = 3.4, 3.5, 12.5 Hz, H-3a), 3.15 (1H, dd, J = 1.5, 10.7 Hz, H-7), 3.46 (1H, dd, J = 7.0, 11.0 Hz, H-4’b), 3.72 (1H, dd, J = 3.5, 11.0 Hz, H-4’a), 4.45 (1H, dd, J = 3.5, 7.0 Hz, H-3’), 4.97 (1H, d (br), J = 10.4 Hz, H-6) , 5.09 (1H, ddd, J = 3.5, 10.5, 11.5 Hz, H8), 5.31 (1H, dd, J = 9.4 and 7.5 Hz, H-1), 5.80 (1H, d, J = 1.5 Hz, H-13b), 6.02 (1H, s, H-5’b), 6.26 (1H, d, J = 10.5 Hz, H-5), 6.33 (1H, s, H-5’a), 6.37 (1H, d, J = 1.5 Hz, H-13a), 9.44 (1H, s, H-15). 13 C NMR (100 MHz, CDCl3): 15.0 (C-14), 22.3 (C-3), 24.1 (C-2), 45.5 (C-9), 49.1 (C-7), 65.0 (C-4’), 69.1 (C-8), 70.1 (C-3’), 75.6 (C-6), 126.1 (C-5’), 129.9 (C-13), 127.78 (C-1), 131.6 (C-10), 132.8 (C-11), 139.3 (C-2’), 142.0 (C-4), 146.7 (C-5), 164.8 (C-1’), 169.2 (C-12), 194.0 (C-15). HRMS: m/z 377.1522 [M+H]+. Acknowledgements - The authors are grateful to the DG-RSDT at the MESRS (Ministery of Scientific Research, Algeria) and to ANDRS for the financial support.
References [1]
Mabberlay DJ. (1997) The Plant Book, 2nd edition. Cambridge University Press, Cambridge.
[2]
(a) Connolly JD, Hill RA. (1991) Dictionary of Terpenoids, vol. 1. Chapman and Hall, London; (b) Rustaiyan A, Niknejad A, Aynehchi Y. (1982) Chemical constituents of Centaurea brugueriana. Planta Medica, 44, 185; (b) Gonzalez AG, Barrera JB, Garcıa TZ, Rosas FE. (1984) Sesquiterpene lactones from Centaurea species. Phytochemistry, 23, 2071–2072; (c) Huneck S, Jakupovic J, Schuster A. (1986) Further compounds from Centaurea stoebe. Planta Medica, 5, 398-399; (d) Skaltsa H, Lazari D, Georgiadou E, Kakavas S, Constantinidis T. (1999) Sesquiterpene lactones from Centaurea species: C. thessala Hausskn. subsp. drakiensis (Freyn & Sint.) Georg and C. attica Nym. subsp. attica. Planta Medica, 65, 393; (e) Skaltsa H, Lazari D, Panagouleas C, Georgiadou E, Garcia B, Sokovic M. (2000) Sesquiterpene lactones from Centaurea species: C. thessala and C. attica. Antifungal activity. Phytochemistry, 55, 903-908; (f) Rosselli S, Maggio AM, Raccuglia RA, Simmonds MSJ, Arnold AN, Bruno M. (2006) Guaianolides from the aerial parts of Centaurea hololeuca. Natural Product Communications, 1, 281-285.
[3]
(a) Rosselli S, Maggio A, Raccuglia RA, Bruno M. (2003) Rearrangement of germacranolides. Synthesis and absolute configuration of elemane and heliangolane derivatives from cnicin. European Journal of Organic Chemistry, 14, 2690-2694; (b) Cardona ML, Garcia B, Navarro FI, Pedro JR. (1994) Sesquiterpene lactones from Centaurea paui. Natural Products Letters, 5, 4754; (c) Nowak G, Drozdz B, Georgiadis T. (1984) Sesquiterpene lactones. XXIX. Cnicin in species of the subgenus Acrolophus (Cass.) Dobrocz. Acta Societatis Botanicorum Poloniae, 53, 199–205.
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849
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Continued inside backcover
