Synthesis and Absolute Configuration of (2S,3S,3aS,6S,7aR)-2,3-Dihydroxy-2-((R)-1-hydroxy-3-methylbutyl)-3,6-dimethylhexahydrobenzofuran-4(2H)-one

To investigate the anti-ulcer effect of bisabolangelone reduction derivatives, the sesquiterpene was further proceeded with dihydroxylation reaction. The structure of the target compound was characterized by IR, ESI-MS, 2D NMR and elemental analysis, and its absolute configuration was confirmed with a Flack parameter of 0.08(16) by X-ray crystallography using a Cu radiation source. Compound(3), C_(15)H_(26)O_5, crystal data: monoclinic system, space group P2_1, a = 11.467(2), b = 6.0303(12), c = 11.711(2) ?, β = 99.70(3)°, V = 798.3(3) ?~3, Z = 2, F(000) = 312, D_c = 1.191 g/cm~3, μ = 0.723 mm~(-1), R = 0.0303 and wR = 0.0797 for 2590 independent reflections(Rint = 0.0164) and 2563 observed ones(I 2σ(I)).