01390nas a2200169   4500008004100000022001400041245007500055210006900130260000900199300001400208490000700222520082100229100002601050700001701076700002201093856010501115       2020                        eng d  a1523-706000aTotal synthesis of beshanzuenone D and its epimers and abiespiroside A0 aTotal synthesis of beshanzuenone D and its epimers and abiespiro  cNOV   a8561-85650 v223 a<p>A unified and protecting-group-free six-step total synthesis of bisabolane-type sesquiterpenoid beshanzuenone D and its stereoisomers and abiespiroside A using S-(+)-carvone as a common chiral-pool building block is disclosed. This synthetic route features chemoselective allylic chlorination of carvone, Au(I)-catalyzed cydoisomerization induced construction of furan from homopropargylic diol, substrate-controlled selective hydroxylation using Davis-oxaziridine, and dye-sensitized photo-oxidation (through O-1(2)) of hydroxyalkyl tethered furan to access oxaspirolactone as key transformations. A comprehensive set of NMR data along with DFT calculations, ECD spectra, and optical rotation measurements of the synthesized beshanzuenone D and its epimers were obtained to confirm absolute configurations.</p>
1 aBorade, Balasaheb, R.1 aDixit, Ruchi1 aKontham, Ravindar  uhttps://library.ncl.res.in/content/total-synthesis-beshanzuenone-d-and-its-epimers-and-abiespiroside