143169-20-4Relevant articles and documents
Molecular and Crystal Structure of Hyptolide, a Naturally Occurring α,β-Unsaturated δ-Lactone
Achmad, Sjamsul,Hoeyer, Thomas,Kjaer, Anders,Makmur, Lukman,Norrestam, Rolf
, p. 599 - 609 (2007/10/02)
Hyptolide, a six-membered, α,β-unsaturated C12 lactone, has been reisolated from Hyptis pectinata Poit.Detailed 1H and 13C NMR spectroscopic studies and a crystal structure determination on the basis of single-crystal X-ray diffraction data collected at 293 K provide evidence for the detailed structure and relative configuration of hyptolide.The crystal structure has been determined from 2261 most significant X-ray intensities and refined to an R factor of 0.065.The space group is P21 and the cell parameters are a = 7.629(2), b = 24.639(3), c = 10.468(2) Angstroem and β = 90.64(2) deg.The absolute configuration is established by synthesis of 10(S),11(R)-dihydroxydodecanoic acid, the enantiomer of an acid previously produced by exhaustive hydrogenation of hyptolide.On the basis of the combined evidence, supported by chiroptical data, hyptolide can now be formulated as 6R-(1Z,3S,5R,6S)-5,6-dihydro-6--2H-pyran-2-one.Its relation to other C12-lactones of natural origin is briefly discussed.
