86990-89-8Relevant academic research and scientific papers
Studies towards the total synthesis of cruentaren A and B: Stereoselective synthesis of fragments C1-C11, C12-C22 and C23-C28
Ganganna, Bogonda,Srihari, Pabbaraja,Yadav, Jhillu Singh
supporting information, p. 2685 - 2689 (2017/06/23)
A convergent and stereoselective approach for the synthesis of C1-C11, C12-C22, and C23-C28 fragments of cytotoxic natural products cruentaren A and B are accomplished. Highlights of the strategy include a Sharpless epoxidation followed by a regioselective opening of epoxide to generate anti and syn-stereochemistry at C9-C10 and C15-C16, an Alder-Rickert reaction between a 1,5-dimethoxy-1,4-cyclohexadiene and dienophile to construct the aromatic ring, and a lithium-mediated aldol reaction to install the C17-C18 anti-stereochemistry. The synthesis of C1-C11 and C12-C22 fragments proceed with a longest linear sequence of 10 and 17 steps from commercially available 2-butyne-1,4-diol and cis-2-butene-1,4-diol respectively.
Studies toward the synthesis of iejimalides A-D: Preparation of the C3-11 and C12-C24 fragments
Sabitha, Gowravaram,Gurumurthy,Yadav, Jhillu Singh
, p. 110 - 118 (2014/01/06)
The convergent synthesis of the C3-C11 and C12-C24 fragments of the iejimalides A-D is described. The C3-C11 fragment is obtained by a cross-metathesis reaction, while the C12-C24 fragment is derived from a Still-Gennari modified Horner-Wadsworth-Emmons o
Formal total synthesis of (-)-5,6-dihydrocineromycine B
Reddy, G. Venkateswar,Kumar, R. Sateesh Chandra,Siva,Babu, K. Suresh,Rao, J. Madhusudana
, p. 2677 - 2681 (2013/01/15)
An efficient and highly convergent formal total synthesis of the 14-membered macrolide (-)-5,6-dihydrocineromycine B is achieved. Key reaction sequences include a Sharpless asymmetric epoxidation followed by esterification for the formation of a fully functionalized acyclic precursor, Corey-Bakshi-Shibata reduction, and ring-closing metathesis, respectively. Georg Thieme Verlag KG Stuttgart · New York.
Highly diastereofacial anti-aldol reaction: Practical synthesis of optically active anti-2-alkyl-3-hydroxycarboxylic acid ester units
Kurosu,Lorca
, p. 1205 - 1209 (2007/10/03)
A variety of esters derived from commercially available norephedrine were used in diastereoselective anti-aldol reactions. The aldol reaction of designed 2-(N-2-methylbenzyl-N-2,4,6-trimethylbenzyl)-amino-1-phenylpropanol esters 4a-d with aldehydes furnished anti-2-alkyl-3-hydroxycarboxylic acid esters in excellent diastereomeric ratios (>98:2) when LDA-Cp2ZrCl2 (0.3 equiv) was used for enolization, followed by transmetalation into the zirconium enolate for aldolization. The novel auxiliary 3 for the anti-aldol reaction does not exhibit the ordinary basicity of tertiary amines; 3 can be extracted from acidic media with organic solvents. Its use is, therefore, very advantageous not only for extraction of the aldol products from the acidic water solutions; but also for recovering the chiral auxiliary 3 after the reductive cleavage. Treatment of aldol or 3-protected aldol products with DIBAL-H or LiAIH4 affords the versatile synthons, 2-alkyl-propane-1,3-diols or those 3-protected diols in >98% ee's together with 3 in nearly quantitative recovery.
Regioselective Alkyl and Alkynyl Substitution Reactions of Epoxy Alcohols by the Use of Organoaluminum Ate Complexes: Regiochemical Reversal of Nucleophilic Substitution Reactions
Sasaki, Minoru,Tanino, Keiji,Miyashita, Masaaki
, p. 1765 - 1767 (2007/10/03)
(matrix presented) Unprecedented nucleophilic substitution reactions of 2,3-epoxy-1-alkanols with alkyl- and alkynylaluminum ate complexes have been studied and demonstrated to occur at the C2 position with extremely high stereoselectivity, i.e., with exa
Isomer Selectivity in Stereocontrolled Payne Rearrangement-epoxide Cleavage of 2,3-Epoxy Alcohols in Aprotic Solvents: Application to an Enantioselective Total Synthesis of (+)-exo-Brevicomin
Page, Philip C. Bulman,Rayner, Christopher M.,Sutherland, Ian O.
, p. 1375 - 1382 (2007/10/02)
Organo-copper and -cuprate reagents may be used to trap the more reactive epoxy alkoxide isomer in a Lewis acid-catalysed Payne rearrangement process.This methodology has been used as the key step in a five-step enantioselective total synthesis of (+)-exo
Enantioselective total synthesis of ingramycin
Tanner, David,Somfai, Peter
, p. 4395 - 4406 (2007/10/02)
An enantioselective total synthesis of the 14-membered macrolide antibiotic ingramycin, 1, is described. In a convergent approach three chiral fragments A,B and C are assembled, the allylic bromide A deriving its chirality from L-serine while the asymmetr
REGIOSELECTIVITY OF THE REACTIONS OF TRIALKYLALUMINUM REAGENTS WITH 2,3-EPOXYALCOHOLS: APPLICATION TO THE SYNTHESIS OF α-CHIRAL ALDEHYDES
Roush, William R.,Adam, Michael A.,Peseckis, Steven M.
, p. 1377 - 1380 (2007/10/02)
Treatment of optically active 2,3-epoxyalcohols with trialkylaluminum reagents followed by periodate cleavage constitutes a convenient synthesis of α-chiral aldehyde derivatives, especially when the branching alkyl group is methyl.
