194610-23-6Relevant academic research and scientific papers
Synthesis of (-)-hennoxazole A: Integrating batch and flow chemistry methods
Fernández, Amadeo,Levine, Zebulon G.,Baumann, Marcus,Sulzer-Mossé, Sarah,Sparr, Christof,Schl?ger, Sabrina,Metzger, Albrecht,Baxendale, Ian R.,Ley, Steven V.
, p. 514 - 518 (2013)
A new total synthesis of (-)-hennoxazole A is reported. The synthetic approach is based on the preparation of three similarly sized fragments resulting in a fast and convergent assembly of the natural product. The three key reactions of the synthesis include a highly stereoselective 1,5-anti aldol coupling, a gold-catalyzed alkoxycyclization reaction, and a stereocontrolled diene cross-metathesis. The synthesis involves integrated batch and flow chemistry methods leading to the natural product in 16 steps longest linear sequence and 2.8% overall yield. Georg Thieme Verlag Stuttgart · New York.
Quinocidin, acytotoxic antibiotic with anunusual 3,4-dihydroquinolizinium ring and michael acceptor reactivity toward thiols
Nakagawa, Yu,Sawaki, Yuki,Kimura, Takahiro,Tomura, Tomohiko,Igarashi, Yasuhiro,Ojika, Makoto
, p. 17894 - 17897 (2019/03/07)
Cytotoxicity-guided fractionation of the culture broth of Actinomadura sp. TP-A0019 led to the isolation of quinocidin (1), acytotoxic antibiotic with an unusual 3,4-dihydroquinolizinium ring. The structural assignment was made on the basis of high-field NMR experiments and chemical synthesis. Comparison ofthe spectral properties of 1 with those of its synthetic counterparts revealed that 1 is aracemic mixture of two enantiomers, which showed similar cytotoxicity against HeLa-S3 cells. Nucleophile-trap-ping experiments demonstrated that 1 captured 2-mer-captoethanol and N-acetyl-l-cysteine by means of aMi-chael addition-type reaction, but was inert toward 2-ami-noethanol and glycolic acid. Notably, the addition of 1 to thiols proceeded smoothly in neutral aqueous media at room temperature. In view of the thiol-trapping ability and the unusual structure, 1 provides aunique scaffold for designing drug leads and protein-labeling probes.
A general synthetic approach to the amnesic shellfish toxins: Total synthesis of (-)-isodomoic acid B, (-)-isodomoic acid E and (-)-isodomoic acid F
Lemiere, Gilles,Sedehizadeh, Simon,Toueg, Julie,Fleary-Roberts, Nadia,Clayden, Jonathan
, p. 3745 - 3747 (2011/05/04)
The alkynylpyrrolidine 4 was made via a dearomatising cyclisation of an aromatic amide, and was elaborated by stannylcupration and palladium-catalysed coupling to achieve the first total synthesis of three members of the isodomoic acid family; the same alkyne can be envisaged as a precursor to several more of this class of amnesic shellfish toxins. The Royal Society of Chemistry.
Total synthesis of (-)-amphidinolide E
Kim, Chan Hyuk,An, Hyo Jung,Shin, Won Kyo,Yu, Wei,Woo, Sang Kook,Jung, Soon Kyu,Lee, Eun
, p. 8019 - 8021 (2007/10/03)
The unique structural features of the cytotoxic marine macrolide (-)-amphidinolide E make it an intriguing synthetic target. Its total synthesis has now been completed by employing a radical cyclization of a β-alkoxy acrylate to form the oxolane ring, a Kocienski-Julia olefination to create the E C=C bond, and a lactonization reaction to close the macrocyclic ring. (Chemical Equation Presented).
Convergent approach to (E)-alkene and cyclopropane peptide isosteres
Wipf, Peter,Xiao, Jingbo
, p. 103 - 106 (2007/10/03)
(Chemical Equation Presented) Trisubstituted (E)-alkene isosteres (TEADIs) and novel cyclopropane amide bond isosteres (CPDIs) were synthesized by aldimine addition and three-component aldimine addition-cyclopropanation methodologies, respectively. These
A One-Pot Multicomponent Coupling Reaction for the Stereocontrolled Synthesis of (Z)-Trisubstituted Allylic Alcohols
Chen, Young K.,Walsh, Patrick J.
, p. 3702 - 3703 (2007/10/03)
In this Communication, we outline a new one-pot, multicomponent coupling reaction that allows easy access to (Z)-trisubstituted allylic alcohols. Our strategy is based on E to Z isomerization of the 1-bromo-1-dialkylvinylborane upon reaction with dialkylzinc reagents, and subsequent transmetalation to give (Z)-trisubstituted vinylzinc species. In situ trapping of the reactive vinylzinc intermediates with aldehydes furnished a series of (Z)-trisubstituted allylic alcohols. This method represents a viable alternative to the Still?Gennari modification of the HWE olefination reaction, and it has the advantage that it allows coupling of larger fragments. Copyright
Synthesis of the J ring segment of gambieric acid
Kadota, Isao,Takamura, Hiroyoshi,Yamamoto, Yoshinori
, p. 3649 - 3651 (2007/10/03)
The J ring segment 2 of gambieric acid was synthesized stereoselectively by the coupling between the cyclic ether component 3 and the alkenyl iodide 4. The tetrahydropyran 3 was stereoselectively synthesized by the 6-endo-cyclization of a hydroxyepoxide prepared from deoxy-D-ribose. The side chain moiety 4 was prepared by the stereoselective hydrostannation of an internal alkyne.
Synthetic studies of an 18-membered antitumor macrolide, tedanolide. 5. Stereoselective synthesis of the C13 - C23 part via condensation of two fragments, C13 - C17 and C18 - C21, by taking advantage of the 3,4- dimethoxybenzyl protecting group
Zheng, Bao-Zhong,Maeda, Hiroshi,Mori, Michiko,Kusaka, Shin-Ichi,Yonemitsu, Osamu,Matsushima, Tomohiro,Nakajima, Noriyuki,Uenishi, Jun-Ichi
, p. 1288 - 1296 (2007/10/03)
An efficient and stereoselective synthesis of the C13 - C23 part (8) was achieved starting from methyl (R) - and (S)-3-hydroxy-2-methylpropionates (9) via coupling of the C13 - C17 aldehyde (6), prepared by Evans asymmetric aldol reaction, with the C18 - C21 iodoalkene (5b) by taking advantage of the 3,4-dimethoxybenzyl protecting group.
