Structure elucidation of a new cycloartane triterpene glycoside from Souliea vaginata by NMR

[1] (a) Y. Kobuke, K. Hanji, K. Horiguchi, M. Asada, Y. Nakayama, J. Furukawa. J. Am. Chem. Soc. 1976, 98, 7414; (b) K. E. Wiegers, S. L. Smith. J. Org. Chem. 1978, 43, 1126; (c) M. de Sousa Healy, A. J. Rest. J. Chem. Soc., Perkin Trans. 1 1985, 973; (d) M. Van Beylen, B. Roland, G. S. D. King, J. Aerts. J. Chem. Res. (S) 1985, 388; (e) M. Van Beylen, B. Roland, G. S. D. King, J. Aerts. J. Chem. Res. M. 1985, 4201; (f) B. Roland, M. Van Beylen, J. Smid. J. Phys. Chem. 1994, 98, 4707; (g) C. J. Pederson, J. M. Lehn, D. J. Cram. Resonance. 2001, 6, 7. [2] L. Ruzicka, Multimembered rings, higher terpene compounds andmale sex hormones, Nobel Lecture, December 12, 1945. [3] (a) E. M. Driggers, S. P. Hale, J. Lee, N. K. Terrett. Nat. Rev. Drug Discov. 2008, 7, 608; (b) A. K. Oyelere. Curr. Top. Med. Chem. 2010, 10, 1359; (c) E. Marsault, M. L. Peterson. J. Med. Chem. 2011, 54, 1961; (d) C. J. White, A. K. Yudin. Nat. Chem. 2011, 3, 509; (e) L. F. Lindoy, K.-M. Park, S. S. Lee. Chem. Soc. Rev. 2013, 42, 1713. [4] (a) J. D. Dunitz (Ed), Perspectives in Structural Chemistry, vol. 2, Wiley, New York, 1968, pp. 1–70; (b) W. C. Still. J. Am. Chem. Soc. 1979, 101, 2493; (c) W. C. Still, I. Galynker. Tetrahedron 1981, 37, 3981; (d) W. C. Still, I. Galynker. J. Am. Chem. Soc. 1982, 104, 1774; (e) W. C. Still, S. Murata, G. Revial, K. Yoshihara. J. Am. Chem. Soc. 1983, 105, 625; (f) W. C. Still, V. J. Novack. J. Am. Chem. Soc. 1984, 106, 1148; (g) F. A. L. Anet, P. J. Degen, I. Yavari. J. Org. Chem. 1978, 43, 3021; (h) E. Vedejs, R. A. Buchanan, Y. Watanabe. J. Am. Chem. Soc. 1989, 111, 8430; (i) J. Mulzer, H. M. Kirstein, J. Buschmann, C. Lehmann, P. Luger. J. Am. Chem. Soc. 1991, 113, 910; (j) D. A. Evans, A. M. Ratz, B. E. Huff, G. S. Sheppard. J. Am. Chem. Soc. 1995, 117, 3448; (k) H. Kim, H. Lee, J. Kim, S. Kim, D. Kim. J. Am. Chem. Soc. 2006, 128, 15851; (l) J. R. Scheerer, J. F. Lawrence, G. C. Wang, D. A. Evans. J. Am. Chem. Soc. 2007, 129, 8968; (m) W. Tu, P. E. Floreancig. Angew. Chem. Int. Ed. 2009, 48, 4567. [5] A. Zinke, E. Ziegler. Ber. dtsch. Chem. Ges. 1944, 77, 264. [6] J. W. Cornforth, P. D’arcy Hart, G. A. Nicholls, R. J. W. Rees, J. A. Stock. Brit. J. Pharmacol. 1955, 10, 73. [7] H. Kämmerer, G. Happel, F. Caesar. Makromol. Chem. 1972, 162, 179. [8] (a) C. D. Gutsche, L. J. Bauer. J. Am. Chem. Soc. 1985, 107, 6052; (b) D. D. Gutsche, L. J. Bauer. J. Am. Chem. Soc. 1985, 107, 6059. [9] M. Chastrette, F. Chastrette. J. Chem. Soc., Chem. Commun. 1973, 534. [10] M. Chastrette, F. Chastrette, J. Sabadie. Org. Synth. 1988, 6, 856. [11] P. D. Williams, E. LeGoff. J. Org. Chem. 1981, 46, 4143. [12] A. J. Rest, S. A. Smith, I. D. Tyler. Inorg. Chim. Acta 1976, 16, L1. [13] (a) V. Blangy, C. Heiss, V. Khlebnikov, C. Letondor, H. Stoeckli-Evans, R. Neier. Angew. Chem. Int. Ed. 2009, 48, 1688; (b) G. Journot, C. Letondor, R. Neier, H. Stoeckli-Evans, D. Savoia, A. Gualandi. Chem. Eur. J. 2010, 16, 4224; (c) G. Journot, C. R. Jones, V. Blangy, R. Neier. Heterocycles. 2012, 85, 749. [14] W. B. Schweizer, in Structure Correlation, ed. H-B. Bürgi and J. D. Dunitz. VCH Verlagsgesellschaft mbH, Weinheim, 1994, 1, ch. 9, 369–404. [15] P. A. Gale, J. L. Sessler, V. Kral, V. Lynch. J. Am. Chem. Soc. 1996, 118, 5140. [16] M. Karplus. J. Am. Chem. Soc. 1963, 85, 2870. [17] C. A. G. Haasnoot, F. A. A. M. DeLeeuw, C. Altona. Tetrahedron 1980, 36, 2783. [18] (a) J. Sandström, Dynamic NMR Spectroscopy, Academic Press, London, New York, 1982; (b)M. Oki, in Applications of Dynamic NMR Spectroscopy to Organic Chemistry, ed. VCH Publishers Inc., Deerfield Beach, Florida, 1985; (c) D. Casarini, L. Lunazzi, A. Mazzanti. Eur. J. Org. Chem. 2010, 2035.