A concise approach for the synthesis of bitungolides: total syntheses of (−)-bitungolide B & E

Abstract

The first total synthesis of (-)-bitungolide B and a second-generation total synthesis of (-)-bitungolide E are described. The cornerstone of the approach comprises a convergent and flexible route involving Brown crotylation, highly diastereoselective substrate controlled Paterson anti-aldol reaction, hydroxyl-directed 1,3-syn/anti reduction, Barton-McCombie deoxygenation and RCM reactions. Via this route, a common intermediate 13 is readily accessible for the synthesis of the family of bitungolides A-E and franklinolides A-C.

Marine natural products

“…), 631,632 strongylodiol G (Strongylophora sp. ), 633,634 bitungolide B (Theonella swinhoei), 635,636 plakortone L (Plakortis clathrata), 637,638 epiplakinic acid F (Plakinastrella sp. ), 639 and its methyl ester (Plakortis halichondrioides), 640,641 gracilioether F (Plakinastrella mamilaris), 642,643 taumycins A and B (revised 1033 and 1034, Fascaplysinopsis sp.…”

The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2014

“…H derivatives [692], gamahonolide A [693], bitungolides [694], anamarine [695], cryptomoscatones D1 and D2 [696,697], an antascomicin A fragment [698], hyptolide [699], and rugulactone derivatives [700]; (6) γ,δ-unsaturated six-membered ring lactones, including those employed in syntheses of an altrose derivative [701];…”

Nickel- and Brønsted Acid-Catalyzed Redox-Neutral Coupling of 1,3-Dienes and Aldehydes for Synthesis of Dienols

“…Dienols are important structural motifs that not only widely exist in numerous bioactive compounds (Figure 1a), [1][2][3][4] but also act as versatile synthons in Diels-Alder reactions 5,6 and other reactions. 7,8 Although numerous methods have been developed to synthesize them, for example Wittig reaction and cross-coupling reactions, [9][10][11][12][13][14][15] carbonyl addition reactions that join diene precursors with carbonyl compounds would undoubtedly be more attractive pathways because of easier availability of carbonyls.…”