01637nas a2200217   4500008004100000022001400041245004700055210004300102260010600145300001400251490000700265520091800272653002901190653001601219653002201235653002001257653002001277100002101297700002401318856007701342       2015                        eng d  a0040-402000aFormal total synthesis of (-)-kumausallene0 aFormal total synthesis of kumausallene  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcNOV  a8577-85840 v713 a<p>Deacetylkumausyne-a penultimate intermediate in Tang's total synthesis of (-)-kumausallene has been synthesized employing a chiral pool approach and thus culminating in a formal total synthesis of kumausallene. The opening of an epoxide with alkyne (use of Birch reduction for the selective construction of E-pent-3-enyl group) and C-allylation have been used to introduce the pendant alkenyl side chains. Initial attempts to execute an alternative to Tang's route comprising a prior installation of the bromoallene unit via bromoetherification and subsequent S(N)2 displacement are unsuccessful. To overcome this, an alternative approach was developed to arrive at Deacetylkumausyne (another natural product that has been synthesized and characterized by Tang's group). Thus, this overall exercise has culminated in a formal total synthesis of (-)-kumausallene. (C) 2015 Elsevier Ltd. All rights reserved.</p>10aBis-THF natural products10aChiral pool10aDeacetylkumausyne10aTotal synthesis10aWittig reaction1 aDas, Shyamsundar1 aRamana, Chepuri, V.  uhttps://library.ncl.res.in/content/formal-total-synthesis-kumausallene-0