01169nas a2200217   4500008004100000022001400041245012000055210006900175260010600244300001200350490000700362520027100369653003100640653002700671653002300698653003800721653002000759100001900779700002400798856012900822       2009                        eng d  a0040-403900aFormal synthesis of (+)-didemniserinolipid B employing a Pd-mediated 6-endo selective alkynediol cycloisomerization0 aFormal synthesis of didemniserinolipid B employing a Pdmediated   aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJAN  a271-2730 v503 a<p>Herein, we describe a concise assembly of central 6,8-dioxabicyclo[3,2,1]octane core of didemniserino-lipid by employing a Pd-mediated alkynediol cycloisomerization and a formal total synthesis of didemniserinolipid (C) 2008 Elsevier Ltd. All rights reserved.</p>10aAlkynol cycloisomerization10aBridged bicyclic ketal10aDidemniserinolipid10aYamaguchi oxirane alkyne coupling10aZipper reaction1 aRamana, C., V.1 aInduvadana, Boddeti  uhttps://library.ncl.res.in/content/formal-synthesis-didemniserinolipid-b-employing-pd-mediated-6-endo-selective-alkynediol-001978nas a2200265   4500008004100000022001400041245017200055210006900227260010600296300001400402490000700416520090400423653003101327653002701358653001401385653002501399653001801424100001901442700002401461700002201485700002501507700003001532700002401562856012601586       2009                        eng d  a0040-402000aInfluence of electronic factors on pd-mediated cycloisomerization: a systematic investigation of competitive 6-exo-dig versus 7-endo-dig cyclizations of sugar alkynols0 aInfluence of electronic factors on pdmediated cycloisomerization  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcNOV  a9819-98320 v653 a<p>Pd-mediated cycloisomerization of 3-C-propargyl-ribo- and allofuranose derivatives was investigated in detail to understand the influence of electronic factors on the regioselectivity (6-exo- vs 7-endo) of alkynol cycloisomerization leading either to a six- or seven-membered ring. In general, the 6-exo-dig mode of cyclization is facile and is independent of electronic factors. With some of the alkynols, a regioselective (7-endo?) hydration of the alkyne unit was observed and this has been attributed to the participation of C(3)-OH. When the C(3)-OH was protected as its benzyl ether, cycloisomerization of these alkynols occurred exclusively in a 6-exo-dig mode resulting in the corresponding [3.2.1]-bicyclic ketals. Additional control experiments conducted were in support of the participation of C(3)-OH in regioselective alkyne hydration. (C) 2009 Elsevier Ltd. All rights reserved.</p>10aAlkynol cycloisomerization10aBridged bicyclic ketal10aPalladium10aSonogashira coupling10aSugar alkynol1 aRamana, C., V.1 aInduvadana, Boddeti1 aSrinivas, Burgula1 aYadagiri, Kommagalla1 aDeshmukh, Madhusudhan, N.1 aGonnade, Rajesh, G.  uhttps://library.ncl.res.in/content/influence-electronic-factors-pd-mediated-cycloisomerization-systematic-investigation-0