Laboratoire
de Chimie des Substances Naturelles et des H└t└rocycles, Universit└ Cadi Ayyad,
Facult└ des Sciences SemLalia, B.P 2390, Marrakech. Maroc. E-mail:
[email protected]| Molbank 2004, M366 |
(3S)-Tosyl-24-methyl-elemo-lanosta-8,24(31)-diene-7,11-dione
N. Mazoir, A. Auhmani, M. Dakir, My. Y. Ait Itto and A. Benharref
Laboratoire
de Chimie des Substances Naturelles et des H└t└rocycles, Universit└ Cadi Ayyad,
Facult└ des Sciences SemLalia, B.P 2390, Marrakech. Maroc. E-mail:
[email protected]
Received: 16 October 2003 / Accepted: 17 February 2004 / Published: 24 February 2004
To a solution of 11 (1g, 1.68mmol) in 20ml of acetone, was added (0.50g, 0.85mmol) of chromic anhydride2. The mixture was maintained at 0＜C during 24h, and washed with 20ml of cold water. Extracted with ethyl acetate, the organic layer was dried over Na2SO4 , and evaporated under reduced pressure. The residue was purified on a silica gel column using hexane/EtOAc (98/2) as eluant to give 2 (0.63g, 60%).
Mp: 160-161 ＜C (Hexane).
MS (EI, 70eV) : 622 (M+.).
1H NMR (300 MHz, CDCl3) d(ppm): 4.15 (dd,J1=12, J2= 4Hz , H-3); 2.43 (s, 3H of tosyle group); 1.22 and 1.25 (2s, 3H-26 , 3H-27); 4.63 and 4.69 (2S, 2H-31).
13C NMR (75 MHz, CDCl3) d(ppm): 89.10 C-3 ; 150.00; 155.00 C8 and C9 ; 199.50; 201.50 C7 and C11; 155.50 C-24 ; 106.50 C-31 ; 121.31 ; 124.36 ; 124.43 ; 126.55, 131.45 and 141.34 (aromatic carbons) IR n(cm-1): 1700 cm-1.
References
1. Benharref, A.; Lavergne, J.-P. Bull. Soc. Chim. Fr. 1985, 965.
2. Clayton, H. ; Heathcock, C. M. ; Matthew, F. S. and Thanim. U. ; J. Org. Chem. 1984, 49, 3264-3274.
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