129029-85-2Relevant articles and documents
Syntheses of Gymnothespirolignans B and C and Non-natural Isomer 9-Epi-gymnothespirolignan B
Ali, Ghada,Cuny, Gregory D.
supporting information, p. 10517 - 10525 (2021/07/31)
Syntheses of polycyclic spiro lignans gymnothespirolignans B and C as well as the unnatural isomer 9-epi-gymnothespirolignan B were accomplished using (R)-Roche ester and an appropriately substituted fluorenone. Key features of the convergent syntheses include coupling of the fluorenone and an iodo-alkene intermediate derived from (R)-Roche ester in the presence of the Lewis acid TiCl(OiPr)3, C9-O bond formation via an SN2 reaction with retention of stereochemistry, and diastereoselective hydrogenations of a common alkene intermediate guided by accessibility or positioning by the C8-methoxy.
Total Synthesis of the Alleged Structure of Crenarchaeol Enables Structure Revision**
Cunha, Ana V.,Havenith, Remco W. A.,Holzheimer, Mira,Minnaard, Adriaan J.,Schouten, Stefan,Sinninghe Damsté, Jaap S.
supporting information, p. 17504 - 17513 (2021/07/06)
Crenarchaeol is a glycerol dialkyl glycerol tetraether lipid produced exclusively in Archaea of the phylum Thaumarchaeota. This membrane-spanning lipid is undoubtedly the structurally most sophisticated of all known archaeal lipids and an iconic molecule in organic geochemistry. The 66-membered macrocycle possesses a unique chemical structure featuring 22 mostly remote stereocenters, and a cyclohexane ring connected by a single bond to a cyclopentane ring. Herein we report the first total synthesis of the proposed structure of crenarchaeol. Comparison with natural crenarchaeol allowed us to propose a revised structure of crenarchaeol, wherein one of the 22 stereocenters is inverted.
INDOLE DERIVATIVES AS ALPHA-1 -ANTITRYPSIN MODULATORS FOR TREATING ALPHA-1 -ANTITRYPSIN DEFICIENCY (AATD)
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Paragraph 00234; 00316; 00778-00779, (2021/10/11)
Indole derivatives as alpha-l-antitrypsin modulators for treating alpha-l-antitrypsin deficiency (AATD).
Identification and Total Synthesis of an Unstable Anticancer Macrolide Presaccharothriolide Z Produced by Saccharothrix sp. A1506
Ikeda, Hiroaki,Kakeya, Hideaki,Kuranaga, Takefumi,Nakagawa, Yusuke,Tamura, Miho,Terada, Sakahiro
supporting information, p. 7106 - 7111 (2021/09/14)
Saccharothriolides A-F are 10-membered microbial macrolides proposed to be generated from their precursors presaccharothriolides X-Z. Previously, we isolated presaccharothriolide X, and its unique natural prodrug-like properties have intrigued us. However
Isobenzofurans as Synthetic Intermediates: Synthesis and Biological Activity of 8-epi-(–)-Ajudazol B
Adair, Liam,Egan, Ben A.,Pearson, Colin M.,Lopez-Gonzalez, Ricardo,Kuchar, Michal,Mendoza-Mendoza, Artemio,Prunet, Jo?lle,Marquez, Rodolfo
supporting information, p. 6661 - 6672 (2020/10/15)
Ajudazol B is a polyketide secondary metabolite, isolated from the myxobacterium Chondromyces crocatus, that exhibits potent biological activity. Herein, we report a convergent total synthesis of 8-epi-(–)-ajudazol B. The key step is a regio-selective alk
Polyoxygenated Tertiary Alcohols: A Kiyooka Approach
Lücke, Daniel,Kalesse, Markus
supporting information, p. 10080 - 10083 (2019/07/18)
A Kiyooka aldol approach for the stereoselective synthesis of tertiary alcohols is presented. This approach allows for the incorporation of different substituents at all three remaining positions at the chiral center bearing the tertiary alcohol. To demon
Preparation of (2R, 3R, 4R)-3-hydroxy-2,4,6-trimethylheptanoic acid via enzymatic desymmertization
Tokairin, Yoshinori,Konno, Hiroyuki
, p. 39 - 45 (2016/12/09)
Synthesis of a unique fatty acyl unit to build the N-terminus of callipeltin A and homophymine B is described. Our approach to access (2R, 3R, 4R)-3-hydroxy-2,4,6-trimethylheptanoic acid uses enzymatic hydrolysis for the desymmetrization of achiral acetate, followed by diastereoselective Roush crotylboration and Wittig olefination for the backbone construction.
Stereospecific Allylic Functionalization: The Reactions of Allylboronate Complexes with Electrophiles
García-Ruiz, Cristina,Chen, Jack L.-Y.,Sandford, Christopher,Feeney, Kathryn,Lorenzo, Paula,Berionni, Guillaume,Mayr, Herbert,Aggarwal, Varinder K.
supporting information, p. 15324 - 15327 (2017/11/06)
Allylboronic esters react readily with carbonyls and imines (π-electrophiles), but are unreactive toward a range of other electrophiles. By addition of an aryllithium, the corresponding allylboronate complexes display enhanced nucleophilicity, enabling addition to a range of electrophiles (tropylium, benzodithiolylium, activated pyridines, Eschenmoser's salt, Togni's reagent, Selectfluor, diisopropyl azodicarboxylate (DIAD), MeSX) in high regio- and stereocontrol. This protocol provides access to key new functionalities, including quaternary stereogenic centers bearing moieties such as fluorine and the trifluoromethyl group. The allylboronate complexes were determined to be 7 to 10 orders of magnitude more reactive than the parent boronic ester.
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
supporting information, 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.
Total synthesis of panaginsene with structural revision
Geum, Sujeong,Lee, Hee-Yoon
supporting information, p. 2466 - 2469 (2014/05/20)
A facile total synthesis of the reported structure for panaginsene through a trimethylenemethane (TMM) diyl mediated tandem cycloaddition reaction revealed that the spectroscopic data of the synthesized structure did not match with the data of the natural
