55444-14-9Relevant academic research and scientific papers
Total synthesis of (+)-blennolide C and (+)-gonytolide C via spirochromanone
Adachi, Kanna,Hasegawa, Sho,Katakawa, Kazuaki,Kumamoto, Takuya
supporting information, p. 4479 - 4482 (2017/10/30)
We report the asymmetric total synthesis of (+)-blennolide C and (+)-gonytolide C isolated from endophytic fungi. The synthesis involved construction of a spirochromanone with a chiral quaternary carbon by the aldol reaction of o-hydroxyacetophenones and
Total synthesis of (-)-morphine
Koizumi, Hifumi,Yokoshima, Satoshi,Fukuyama, Tohru
supporting information; experimental part, p. 2192 - 2198 (2011/06/19)
We have developed an efficient total synthesis of (-)-morphine in 5% overall yield with the longest linear sequence consisting of 17 steps from 2-cyclohexen-1-one. The cyclohexenol unit was prepared by means of an enzymatic resolution and a Suzuki-Miyaura coupling as key steps. Construction of the morphinan core features an intramolecular aldol reaction and an intramolecular 1,6-addition. Furthermore, mild deprotection conditions to remove the 2,4-dinitrobenzenesulfonyl (DNs) group enabled the facile construction of the morphinan skeleton. We have also established an efficient synthetic route to a cyclohexenol unit containing an N-methyl-DNsamide moiety.
New organofluorine building blocks: Inhibition of the malarial aspartic proteases plasmepsin II and IV by alicyclic α,α-difluoroketone hydrates
Faeh, Christoph,Hardegger, Leo A.,Baitsch, Lukas,Schweizer, W. Bernd,Meyer, Solange,Bur, Daniel,Diederich, Francois
experimental part, p. 3947 - 3957 (2009/12/05)
The development of new therapeutic agents against malaria has become urgent during the past few decades, due to an increased prevalence of drug-resistant strains of malaria-causing Plasmodium parasites. Possible targets are the hemoglobin-degrading aspartic proteases, the plasmepsins. While acyclic α,α-difluoroketone hydrates have been introduced into peptidomimetics to bind to the catalytic Asp dyad of aspartic proteases, alicyclic derivatives were unknown. This paper describes a versatile synthesis of hydrated alicyclic α,α-difluoro-cyclopentanones and -cyclohexanones, decorated with appropriate substituents to fill the S1/S3 and the "flap-open" pocket at the enzyme active sites. Their biological activity was tested against plasmepsin II and IV, revealing an IC50 value (concentration of an inhibitor at which 50% maximum initial velocity is observed) of 7 μM for the best ligand. Reference inhibitors with a protonated secondary ammonium centre to address the catalytic dyad showed similar binding affinities. The X-ray crystal structure of a cyclic α,α- difluoroketone hydrate revealed the ability of these novel building blocks to participate in H-bonding networks. The hydration of difluoroketones was also investigated in solution. An exemplary study showed that the equilibrium constants for the hydration of α,α-difluorinated cyclohexanones are much higher than those for the corresponding cyclopentanones.
Influence of Michael acceptor stereochemistry on intramolecular Morita-Baylis-Hillman reactions
Teng, Wen-Dong,Huang, Rui,Kwong, Cathy Kar-Wing,Shi, Min,Toy, Patrick H.
, p. 368 - 371 (2007/10/03)
A study of the effect of Michael acceptor stereochemistry on the efficiency of intramolecular Morita-Baylis-Hillman (MBH) reactions has been performed. The reactions were catalyzed by a phosphine, and the reaction substrates studied were enones containing
Chemoenzymatic synthesis of α′- And α-acetoxylated cyclic ketones
Tanyeli, Cihangir,Turkut, Engin,Akhmedov, Idris Mecidoglu
, p. 1729 - 1733 (2007/10/03)
α,β-Unsaturated and saturated cyclic ketones were selectively oxidized at the α′- and α-positions using Mn(OAc)3 and Pb(OAc)4, respectively, resulting in high chemical yields. The resultant racemic α′- and α-acetoxylated substrates were resolved into corresponding enantiomerically enriched α′- and α-hydroxylated and acetoxylated compounds with 96-98% ee via PLE hydrolysis. The absolute configurations of α′-acetoxy-α,β-unsaturated cyclic ketones were determined by transforming them into the corresponding saturated α-acetoxy cyclic ketones of known absolute configuration.
The intramolecular Baylis-Hillman reaction: Easy preparation of versatile substrates, facile reactions, and synthetic applications
Yeo, Jung Eun,Yang, Xiuling,Kim, Hee Jin,Koo, Sangho
, p. 236 - 237 (2007/10/03)
We have developed a general and highly efficient method for the preparation of diverse ω-formyl-aα,β-unsaturated carbonyl compounds and optimized the conditions for the intramolecular Baylis-Hillman reactions of these compounds to provide various biologic
Synthesis of 2,3-dihydrobenzofurans by Mn(OAc)3-based oxidative cycloaddition of 2-cyclohexenones with alkenes. Synthesis of (±)-conocarpan
Snider, Barry B.,Han, Luning,Xie, Chaoyu
, p. 6978 - 6984 (2007/10/03)
Oxidative cycloaddition of a 2-cyclohexenone or α-tetralone and an alkene with dried Mn(OAc)3 in benzene at 80-140 °C provides a general route to dihydrobenzofurans 15 and dihydronaphthofurans 17. Although the yields are modest, this one-pot reaction provides simple access to these compounds, which have previously been prepared by multistep routes. Oxidative cycloaddition of 2-cyclohexenones with β-methylstyrenes provides a new route to benzofuranoid neolignans, which was applied to the synthesis of conocarpan (22). The formation of 2-acetoxyhexanedioic acids 27 and 47 from acetoxylation of 2-cyclohexenones in HOAc, but not in benzene, opens up a new class of Mn(OAc)3 reactions and explains Watt and Demir's discovery that much higher yields of α'-acetoxy enones are obtained in benzene than in HOAc.
