1140971-65-8Relevant academic research and scientific papers
Stereoselective total synthesis of etnangien and etnangien methyl ester
Li, Pengfei,Li, Jun,Arikan, Fatih,Ahlbrecht, Wiebke,Dieckmann, Michael,Menche, Dirk
supporting information; experimental part, p. 2429 - 2444 (2010/07/06)
A highly stereoselective joint total synthesis of the potent polyketide macrolide antibiotics etnangien and etnangien methyl ester was accomplished by a convergent strategy and proceeds in 23 steps (longest linear sequence). Notable synthetic features include a sequence of highly stereoselective substrate-controlled aldol reactions to set the characteristic assembly of methyl- and hydroxyl-bearing stereogenic centers of the propionate portions, an efficient diastereoselective Heck macrocyclization of a deliberately conformationally biased precursor, and a late-stage introduction of the labile side chain by means of a high-yielding Stille coupling of protective-group-free precursors. Along the way, an improved, reliable protocol for a Z-selective Stork?Zhao?Wittig olefination of aldehydes was developed, and an effective protocol for a 1,3-syn reduction of sterically particularly hindered β-hydroxy ketones was devised. Within the synthetic campaign, a more detailed understanding of the intrinsic isomerization pathways of these labile natural products was elaborated. The expedient and flexible strategy of the etnangiens should be amenable to designed analogues of these RNA-polymerase inhibitors, thus enabling further exploration of the promising biological potential of these macrolide antibiotics.
Total synthesis of etnangien
Li, Pengfei,Li, Jun,Arikan, Fatih,Ahlbrecht, Wiebke,Dieckmann, Michael,Menche, Dirk
supporting information; experimental part, p. 11678 - 11679 (2009/12/08)
(Chemical Equation Presented) The first total synthesis of the potent RNA-polymerase inhibitor etnangien is described, which establishes unequivocally the relative and absolute configuration of this sensitive macrolide antibiotic. Key features of the expe
Alkyne-enol ether cross-metathesis in the presence of CuSO4: Direct formation of 3-substituted crotonaldehydes in aqueous medium
Castagnolo, Daniele,Botta, Lorenzo,Botta, Maurizio
supporting information; experimental part, p. 3172 - 3174 (2009/08/07)
An efficient synthesis of 3-substituted crotonaldehydes via alkyne-enol ether cross-metathesis in the presence of CuSO4 and in aqueous medium was developed. Crotonaldehydes were obtained in good yields from terminal aryl-alkynes as well as from
