29783-26-4Relevant articles and documents
Structure-activity relationships of untenone a and its derivatives for inhibition of DNA polymerases
Saito, Fumiyo,Takeuchi, Ryo,Kamino, Tomoyuki,Kuramochi, Kouji,Sugawara, Fumio,Sakaguchi, Kengo,Kobayashi, Susumu
, p. 1975 - 1977 (2004)
We found that untenone A and mannzamenone A inhibit mammalian DNA polymerases α and β, and human terminal deoxynucleotidyl transferase (TdT). The syntheses of both compounds and the structure-activity relationships of untenone A derivatives are described.
Molecular Design of Crown Ethers. 6. Substitution Effect in 16-Crown-5
Inoue, Yoshihisa,Wada, Kazuhito,Liu, Yu,Ouchi, Mikio,Tai, Akira,Hakushi, Tadao
, p. 5268 - 5272 (1989)
A number of 14-, 15-, and/or 16-substituted 16-crown-5 derivatives were synthesized for systematic analysis of the effect of substitution in these crown ethers.The cation-binding ability of substituted 16-crown-5 rings was evaluated by the solvent extraction technique and found to be a critical function of the position, number, type, and stereochemistry of the substituent(s) introduced.Both 15- and 14/16-substituted 16-crown-5 exhibited gradually decreased extractabilities with increasing substitution, although the profiles of change in extractability were distinctly different between 15- and 14/16-substitution.The substitution-induced decrease of extractability is attributed to the limited access of counteranion and/or to the lack of conformational adjustments necessary to make a structure suitable for complex formation.The bridging substitutions at 14- and 16-positions dramatically enhanced the extractabilities for all cations without lowering the original relative cation selectivity.This may arise from the favorable entropic contribution of the conformational freezing by bridging substitution.
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Blomquist,Mayes
, p. 134,139 (1945)
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Chemoselective formation of cyclo-aliphatic and cyclo-olefinic 1,3-diolsviapressure hydrogenation of potentially biobased platform molecules using Kn?lker-type catalysts
Alsters, Paul L.,Chou, Khi Chhay,De Wildeman, Stefaan M. A.,Faber, Teresa,Hadavi, Darya,Han, Peiliang,Quaedflieg, Peter J. L. M.,Schwalb Freire, Alfonso J.,Verzijl, Gerard K. M.,van Slagmaat, Christian A. M. R.
, p. 10102 - 10112 (2021/08/03)
The hydrogenative conversions of the biobased platform molecules 4-hydroxycyclopent-2-enone and cyclopentane-1,3-dione to their corresponding 1,3-diols are established using a pre-activated Kn?lker-type iron catalyst. The catalyst exhibits a high selectivity for ketone reduction, and does not induce dehydration. Moreover, by using different substituents of the ligand, thecis-transratio of the products can be affected substantially. A decent compatibility of this catalytic system with various structurally related substrates is demonstrated.
Nickel-mediated reductive coupling of neopentyl bromides with activated alkenes at room temperature and its synthetic application
Ouyang, Yan,Peng, Yu,Li, Wei-Dong Z.
, p. 4486 - 4496 (2019/07/05)
Reductive coupling of sterically hindered neopentyl bromides with activated alkenes mediated by the in situ generated Ni(0) complexes along with some feedstock is achieved in good yield under the mild conditions. This practically useful method of C(sp3)?C(sp3) bond formation provides a complementary approach to the traditional conjugate addition of preformed organometallic reagents to electrophilic olefins, which often requires cryogenic temperature and rigorous exclusion of air and moisture. The robust application of this reductive coupling reaction was demonstrated in a formal synthesis of stereodivergent (?)-copacamphor and (?)-ylangocamphor, which are valuable intermediates for a class of tricyclo[5.3.0.03,8]decane sesquiterpenes. Moreover, this convenient protocol resulted in a facile access to the homolog of Corey aldehyde en route to prostaglandins, implying the possible involvement of radical-like species.