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60249101195
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1H and 13C NMR were recorded at room temperature using a Varian Gemini 200 (Varian, Palo Alto, CA, USA) in the solvents indicated, with TMS as internal standard. Chemical shifts (δ) are given in ppm and coupling constants (J) in Hertz. IR spectra were recorded using Perkin-Elmer and Nicolet IRFT. The mass spectra were obtained at 70 eV in a VG-autospec. The fragments were described as a relation between atomic mass units and the charge (m/z) and the relative abundance in percentage of the base peak intensity. General procedure for the synthesis of the spirolactones 4 and 5: 3 g of finely divided metallic copper, under strong agitation, was added to 1 mmol of the corresponding quinone dissolved in 10 mL of acetic acid. The reaction mixture was stirred at 60 °C for 20 h. After the end of the reaction was confirmed by TLC, the mixture was added to H2O and extracted with CH2Cl2 (3 × 50 mL) and washed several times with
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3).
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37049120699
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Burnett, A. R, Thomson, R. H. J. Chem. Soc. 1968, 850-853. Procedure for the synthesis of 2,2,2′,2′-tetramethyl-3,4,5,6,3′,4′-hexahydro-2H,2′H-[5,5′]bi[benzo[h]chromenyl]-6,6'-diol (6, To a solution of β-lapachone (1 mmol) in 10 mL of acetic acid was added 2.5 mL of HI under agitation. Soon after the mixture was refluxed for 2 h it was added to a solution of metabisulfite 2, The precipitate that was formed was filtered and washed with H2O distilled. The product was crystallized from benzene and was obtained as a white solid in 96% yield, mp 125 °C. λmax (EtOH) nm (log ε, 340, 331, 252, 211. MS [70 eV, m/z, 454(100, 398(30, 227(17, IR (KBr) cm-1: 3483, 2970, 2929, 2579, 1592, 1388, 765. 1H NMR (200 MHz, CDCl3) δ: 8.2-8.1 (4H, m, 7.6-7.4 (4H, m, 4.9 (2H, s, 2.5-2.2 (4H, m, 1.8 (4H, t, J, 7.0 Hz, 1.4 (12H, s, 13C NMR 50 MHz, CDCl3
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3) δ: 8.1-8.0 (2H, m), 7.5-7.4 (2H, m), 6.5 (1H, s), 2.8 (2H, t), 1.8 (2H, t), 1.4 (6H, s).
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note
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60249098202
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Enraf-Nonius COLLECT; Nonius BV: Delft, The Netherlands (1997-2000).
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Enraf-Nonius COLLECT; Nonius BV: Delft, The Netherlands (1997-2000).
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0031059866
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Carter C.W., and Sweet R.M. (Eds), Academic Press, New York
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Otwinowski, Z.1
Minor, W.2
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Allen F.H., Kennard O., Watson D.G., Brammer L., Orpen A.G., and Taylor R. J. Chem. Soc., Perkin Trans. II (1987) S1-19
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Allen, F.H.1
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Taylor, R.6
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