2161-16-2Relevant academic research and scientific papers
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.
Phosphonate modification for a highly (Z)-selective synthesis of unsaturated esters by Horner-Wadsworth-Emmons olefination
Touchard, Francois P.
, p. 1790 - 1794 (2007/10/03)
The Horner-Wadsworth-Emmons (HWE) reaction of various ethyl diarylphosphonoacetates with benzaldehyde, cyclohexane carboxaldehyde and octanal is reported. Selectivities of up to 98% at -78°C are obtained with the three substrates. Among all the phosphonates prepared, the reagent based on 2-tert-butylphenol proved to be especially efficient, with Z/E ratios close to 95:5 at 0°C. It appears thus to be the reagent of choice for the (Z)-selective HWE reaction with both aromatic and aliphatic aldehydes. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Studies on aryl H-phosphonates. 3. Mechanistic investigations related to the disproportionation of diphenyl H-phosphonate under anhydrous basic conditions
Kers, Annika,Kers, Inger,Stawinski, Jacek,Sobkowski, Michal,Kraszewski, Adam
, p. 9931 - 9944 (2007/10/03)
Diphenyl H-phosphonate undergoes under anhydrous reaction conditions a base-promoted disproportionation to triphenyl phosphite and phenyl H- phosphonate. On the basis of 31P NMR data the most likely mechanism for this transformation was proposed. In order to substantiate these findings and to get a deeper insight into the chemistry of aryl H-phosphonate esters, we carried out also some studies on activation of phenyl and diphenyl H- phosphonates with various condensing agents. We found that aryl vs alkyl esters of phosphonic acid often follow different reaction pathways during the activation, and this can most likely be traced back to higher electrophilicity of the phosphorus centre and to higher reactivity of the P- H bonds in aryl H-phosphonate derivatives.
Separation of phosphorus(III) ligands into pure σ-donors and σ-donor/π-acceptors: Comparison of basicity and σ-donicity
Rahman, Md. Matiur,Liu, Hong-Ye,Eriks, Klaas,Prock, Alfred,Giering, Warren P.
, p. 1 - 7 (2008/10/08)
The separation of phosphorus(III) ligands into two distinct groups identified as pure σ-donor ligands and σ-donor/π-acceptor ligands for the acetyl and methyl complexes, (η-Cp)FeL(CO)COMe, (η-Cp′)FeL-(CO)COMe (Cp′ = MeC5H4), and (η-Cp)FeL(CO)Me, is accomplished by correlation of the terminal carbonyl stretching frequencies with the EL°′ values. The basicity (pKa value of HPR3+) is related primarily to the σ-donicity (the ability of a ligand to donate σ-electrons to a transition metal) and to a lesser degree to the size of the ligand. We conclude that pKa values are reasonable measures of the σ-donicity for those ligands that are pure σ-donor ligands; a better measure are the χ values for those ligands that are pure σ-donors for both the iron complex and LNi(CO)3.
