Zanthodione

.


Spectroscopic data
Zanthodione (I): orange needles; mp. 254-256 °C; 

UV (MeOH) λ_max (log E) 239 (sh) (4.49), 249 (4.51), 392 (sh) (3.58), 408 (4.51), 428 (3.58) ñm; 

IR (KBr) v_max 3389 (OH); 1660, 1646 (C=0); 1601, 1460 (aromatic ring C=C); 1040, 94°6^X(OCH₂0) cm^-1; 

¹H NMR (CDC1₃, 600 MHz) δ 6.40 (2H, s, OCH₂0), 7.73 (1H, br ddd, J = 8.4, 7.2, 1.8 Hz, H-10), 7.77 (1H, dt, J = 7.2, 1.2 Hz, H-9), 8.04 (1H, s, H-7), 8.26 (1H, s, NH exchangeable with D₂0), 8.29 (1H, dd, J = 7.2, 1.8 Hz, H-8), 9.26 (1H, d, J = 8.4 Hz, H-ll), 11.98 (1H, s, OH exchangeable with D₂0); 

EIMS m/z 307 [M]⁺ (90); 

HRESIMS m/z 307.1481 (caled for C₁₇H₉NO_s, 307.1480).




Zanthodione (I) was obtained as orange needles. Its molecular formula C₁₇H₉NO_s was established by EIMS ([M]⁺, m/z 307) and HRESIMS. The UV spectrum showed absorption máxima at 239 (sh), 240, 249, 392 (sh), 408, 428 nm, that indicated the presence of a 4,5-dioxoaporphine skeleton.^11,12 Its IR spectrum indicated the presence of OH/NH (3000—3389 cm^-1), two aryl ketone C=0 (1660, 1646 cm^-1), one methylenedioxy (1040, 940 cm¹) and a six-membered lactam (1587 cm^-1) functionalities. The ¹H NMR spectrum revealed five aromatic protons, two D₂0 exchangeable singlets of a H-bonded phenolic hydroxyl [8 11.98 (1H, s)], and an amidocarbonyl proton at 8 8.26 (1H, s), and a methylenedioxy group at 8 6.40 (2H, s). Five aromatic protons of the spectrum closely resembled those of other 7,8,9,10,11-unsubstituted dioxoaporphine.^11,12 Therefore, the methylenedioxy group had to be on ring A. The singlet at δ 8.04 (1H, s) was ascribed to H-7 while H-8, H-9, H-10 and H-ll appeared as a complex ABCX coupling system. In agreement with the spectra of other C-11-unsubstituted aporphines, dehydro- and oxoaporphines, the most downfield doublet [δ 9.26 (1H, s)] was characteristic of H-ll, the 2H [δ 7.73 (1H, ddd, J = 8.4, 7.2, 1.8 Hz), 7.77 (1H, dt, J = 7.2, 1.2 Hz)] were assigned to H-10, 9, and another proton at 6 8.29 (1H, dd, J = 7.2, 1.8 Hz) was due to H-8. The correlations of H-7/NH, and H-8/H-7, 9 were also disclosed in the NOESY experiment (Fig. 1) and further supported the position of above assignments. By means of ¹H-NMR, ¹H,¹H-COSY, and NOESY (Fig. 1) data, the structure of zanthodione was shownto be 4-hydroxy-7H-benzo[g][l,3]dioxolo[4',5';4,5 ]benzo[l,2,3-úfe]quinoline-5,6-dione (1).

 see...................
 http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072008000300019&lng=en&nrm=iso&ignore=.html



J. Chil. Chem. Soc, 53, N° 3 (2008) págs: 1631-1634

CHEMICAL CONSTITUENTS FROM THE STEM BARK OF ZANTHOXYLUM SCANDENS

MING-JEN CHENG^1,2,3 CHUAN-FANG LIN^1,3 HSUN-SHUO CHANG¹, IH-SHENG CHEN¹*
¹Graduate Institute of Natural Products , College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan 807, Republic of China.
²M.-J. C. and C.-F. L. contributed equally to the work in this paper.
Bioresource Collection and Research Center (BCRC), Food Industry Research and Development Institute (FIRDI), Hsinchu, Taiwan 300, Republic of China.

Journal of the Chilean Chemical Society

On-line version ISSN 0717-9707

J. Chil. Chem. Soc. vol.53 no.3 Concepción Sept. 2008

http://dx.doi.org/10.4067/S0717-97072008000300019 

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