01443nas a2200157   4500008004100000245005600041210005200097260000800149300001600157490000700173520087000180653011001050100002301160700001701183856008501200       2013                        eng d00aSynthesis of C(27)–C(38) fragment of aflastatin A0 aSynthesis of C27–C38 fragment of aflastatin A  cJAN  a1830–18400 v693 a<p>Efforts at finding out a strategy for the synthesis of the densely hydroxylated C(27)–C(48) fragment of aflastatin A have been described. The initial studies dealing with alkyne–epoxide coupling using a linear polyol epoxide resulted in a debenzylative cycloetherification leading to a C-arabinoside derivative. This problem has been addressed by applying an epoxide pendant on a furanosyl unit. With the model alkyne, the epoxide–alkyne coupling proceeded smoothly. Subsequently, following a sequence of [Pd]-mediated alkynone cycloisomerization/stereoselective hydroboration–oxidation, the synthesis of the central C(27)–C(38) fragment has been executed. When employed, the original C(33)–C(48) alkyne, the coupling and the cycloisomerizations are facile. However, the resulting glycals are unstable, thus warranting a revision in our approach.</p>10aAflastatin; Epoxide–alkyne coupling; ω-Alkynone cycloisomerization; Palladium catalysis; Hydroboration1 aNarute, Sachin, B.1 aRamana, C.V.  uhttps://library.ncl.res.in/content/synthesis-c27%E2%80%93c38-fragment-aflastatin