132487-16-2Relevant academic research and scientific papers
Open-Close Strategy toward the Organocatalytic Generation of 2-Deoxyribosyl Oxocarbenium Ions: Pyrrolidine-Salt-Catalyzed Synthesis of 2-Deoxyribofuranosides
Ghosh, Titli,Mukherji, Ananya,Kancharla, Pavan K.
, p. 7488 - 7498 (2019)
The reaction of secondary amine salts with 2-deoxy-ribofuranoses under forcible conditions leads to the putative furanosyl oxocarbenium ion that is trapped with various alcohols to provide 2-deoxy-ribofuranosides. The observed anomeric selectivities range from an equimolar mixture to complete α-selectivity in the case of bulky sugar acceptors. Owing to the mechanism and temperature of the transformation, the generated oxocarbenium ion shows little or no facial preference towards the nucleophilic attack of non-carbohydrate acceptors and leads to a mixture of anomers in the case of benzyl and acetyl protected donors. However, the conformationally less flexible tetraisopropylsilyl protected donor reacted with both sugar and non-sugar acceptors in a stereoselective fashion. Besides, the glycosylation with 2-cyanoethanol gave the product with unexpected beta-selectivity presumably due to nitrile effect. The operationally simple organocatalytic protocol provides easy access to otherwise difficult 2-deoxy-ribofuranosides/disaccharides.
Studies on the generation of unnatural C-nucleosides with 1-alkynyl-2-deoxy-D-riboses
Adamo, Mauro F. A.,Pergoli, Roberto
, p. 4443 - 4446 (2007)
(Chemical Equation Presented) 1-Alkynyl-2-deoxy-D-riboses 7 and 8 were independently synthesized and subsequently used to generate several novel C-nucleosides.
Highly Stereoselective Glycosylation Reactions of Furanoside Derivatives via Rhenium (V) Catalysis
Casali, Emanuele,Othman, Sirwan T.,Dezaye, Ahmed A.,Chiodi, Debora,Porta, Alessio,Zanoni, Giuseppe
, p. 7672 - 7686 (2021/06/21)
A novel approach for the formation of anomeric carbon-functionalized furanoside systems was accomplished through the employment of an oxo-rhenium catalyst. The transformation boasts a broad range of nucleophiles including allylsilanes, enol ethers, and aromatics in addition to sulfur, nitrogen, and hydride donors, able to react with an oxocarbenium ion intermediate derived from furanosidic structures. The excellent stereoselectivities observed followed the Woerpel model, ultimately providing 1,3-cis-1,4-trans systems. In the case of electron-rich aromatic nucleophiles, an equilibration occurs at the anomeric center with the selective formation of 1,3-trans-1,4-cis systems. This anomalous result was rationalized through density functional theory calculations. Different oxocarbenium ions such as those derived from dihydroisobenzofuran, pyrrolidine, and oxazolidine heterocycles can also be used as a substrate for the oxo-Re-mediated allylation reaction.
Highly stereoselective synthesis of aryl/heteroaryl-: C -nucleosides via the merger of photoredox and nickel catalysis
Ma, Yingying,Liu, Shihui,Xi, Yifan,Li, Hongrui,Yang, Kai,Cheng, Zhihao,Wang, Wei,Zhang, Yongqiang
supporting information, p. 14657 - 14660 (2019/12/11)
A photoredox/nickel dual-catalyzed decarboxylative cross-coupling reaction of anomeric ribosyl/deoxyribosyl acids with aryl/heteroaryl bromides has been developed. The reaction proceeds smoothly under visible-light irradiation and features the using of cost-effective and easily handled catalysts and starting materials, which allows the highly stereoselective synthesis of diverse aryl/heteroaryl-C-nucleosides in moderate to high yields.
Secondary amine salt catalyzed controlled activation of 2-deoxy sugar lactols towards alpha-selective dehydrative glycosylation
Ghosh, Titli,Mukherji, Ananya,Srivastava, Hemant Kumar,Kancharla, Pavan K.
supporting information, p. 2870 - 2875 (2018/05/03)
A new organocatalytic glycosylation method exploiting the lactol functionality has been disclosed. The catalytic generation of glycosyl oxacarbenium ions from lactols under forcible conditions via weakly Br?nsted-acidic, readily available secondary amine salts affects the diastereoselective glycosylation of 2-deoxypyranoses and furanoses. This operationally simple iminium catalyzed activation of 2-deoxy hemi-acetals is a potential alternative to the existing cumbersome methods that need specialized handling. The mechanisms for this unique transformation and kinetic/thermodynamic effects have been discussed based on both experimental evidence and theoretical studies.
COMPOSITION COMPRISING PAEONIFLORIN OR ALBIFLORIN ANALOGUE, METHOD OF PREPARATION THEREOF
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Page/Page column 20; 21, (2018/04/20)
A composition comprises a compound of formula (I) and at least one cosmetically acceptable carrier. It can be used for preventing or decreasing skin pigmentation and /or lightening skin tone.
Zeolite-Based Organic Synthesis (ZeoBOS) of Acortatarin A: First Total Synthesis Based on Native and Metal-Doped Zeolite-Catalyzed Steps
Wimmer, Eric,Borghèse, Sophie,Blanc, Aurélien,Bénéteau, Valérie,Pale, Patrick
supporting information, p. 1484 - 1489 (2017/02/10)
Similarly to polymer-supported assisted synthesis (PSAS), organic synthesis could be envisaged being performed by using zeolites, native or metal-doped, as heterogeneous catalysts. To illustrate this unprecedented Zeolite-Based Organic Synthesis (ZeoBOS),
Efficient synthesis of fluorescent alkynyl C-nucleosides via Sonogashira coupling for the preparation of DNA-based polyfluorophores
K?lmel, Dominik K.,Barandun, Luzi J.,Kool, Eric T.
supporting information, p. 6407 - 6412 (2016/07/15)
A facile and general procedure for the preparation of alkynyl C-nucleosides with varied fluorophores is presented. Sonogashira coupling was used as a key reaction to conjugate the dyes to an easily accessible ethynyl functionalized deoxyribose derivative.
Design, synthesis, and biological evaluation of C1-phosphonamidate analogues of 2-deoxy-d-ribose-1-phosphate
Quintiliani, Maurizio,Balzarini, Jan,McGuigan, Christopher
, p. 9111 - 9119 (2013/09/24)
A novel series of phenoxy C1-phosphonamidate derivatives of 2-deoxy-d-ribose have been synthesised as stable analogues of 2-deoxy-α-d-ribose-1-phosphate. A number of synthetic routes were explored for the preparation of these targets. The successful approach involved the synthesis of a protected C1-phosphonate ester 17 via Michaelis-Arbuzov reaction, which was then hydrolysed and coupled with different amino acid esters using aldrithiol. Subsequent hydrogenolysis afforded the targets 2a-g, which were isolated as a mixture of diastereoisomers. The compounds were assayed for inhibition of thymidine phosphorylase (TP) and uridine phosphorylase (UP) and for antiviral and cytostatic activity.
A new DNA building block, 4′-selenothymidine: Synthesis and modification to 4′-seleno-AZT as a potential anti-HIV agent
Alexander, Varughese,Choi, Won Jun,Chun, Jeongha,Kim, Hea Ok,Jeon, Ji Hye,Tosh, Dilip K.,Lee, Hyuk Woo,Chandra, Girish,Choi, Jungwon,Jeong, Lak Shin
supporting information; experimental part, p. 2242 - 2245 (2010/08/05)
The first synthesis of 4′-selenothymidine (1), a novel DNA building block, and 4′-seleno-AZT (2) was accomplished from 2-deoxy-d-ribose via stereoselective formation of 2-deoxy-4-seleno-d-furanose 17 and a Pummerer-type base condensation as key steps. 4′-
