6554-17-2Relevant articles and documents
Stereoselective synthesis of 2′-modified nucleosides by using ortho-alkynyl benzoate as a gold(i)-catalyzed removable neighboring participation group
Ding, Haixin,Li, Chuang,Zhou, Yirong,Hong, Sanguo,Zhang, Ning,Xiao, Qiang
, p. 1814 - 1817 (2017/01/21)
In the present paper, we report a novel strategy for highly efficient stereoselective synthesis of 2′-modified nucleosides by using ortho-alkynyl benzoate as neighboring participation group. Subsequently, ortho-alkynyl benzoate can be removed smoothly in the presence of 5 mol% Ph3PAuCl-AgOTf in dichloromethane with H2O (1 eq.) and ethanol (6 eq.) to afford 2′-OH nucleosides in high yields and selectivity.
A gemcitabine hydrochloride method for the preparation of
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Paragraph 0035-0038, (2017/03/25)
The invention relates to a preparation method of gemcitabine hydrochloride, and the preparation method is a new process method and comprises the following steps: firstly preparing 3',5' and N-protected cytidine by using cytidine as a raw material, oxidizing to obtain 2'-keto-cytidine intermediate, and then preparing gemcitabine through catalystic deoxidation bi-fluorination by using a novel efficient deoxidation fluorination reagent. Compared with the widely used method for preparing gemcitabine by coupling fluorinated deoxyribose and cytosine base at present, the possibility of generating an alpha isomer is completely eliminated; the possibility of generating the alpha isomer is eliminated since the reaction of cytosine base configuration is not involved, the product can be easily purified, the purification process is greatly simplified, an efficient and practical new process method is provided for preparing the gemcitabine, and high industrial application value is realized.
REGIOSELECTIVE PROTECTION OF CARBOHYDRATE DERIVATIVES. PART. 20. SIMPLE, EFFICIENT 2'-O-DEACYLATION OF FULLY ACYLATED PURINE AND PYRIMIDINE RIBONUCLEOSIDES THROUGH tert-BUTOXIDE
Nishino, Shigeyoshi,Takamura, Hatsuko,Ishido, Yoshiharu
, p. 1995 - 2004 (2007/10/02)
A simple treatment of fully aroylated purine and pyrimidine ribonucleosides with pulverized potassium tert-butoxide in tetrahydrofuran (THF) or dichloromethane under a controlled condition gave a mixture of the corresponding di-O-aroyl derivatives in which 2'-OH derivatives are preponderant over 3'-OH derivatives; 3',5'-di-O-benzoyluridine, N4,3',5'-tribenzoylcytidine, N4,3',5'-tri-O-toluoylcytidine, N2,3',5'-tribenzoylguanosine, and N2,isobutyryl-3',5'-di-O-benzoylguanosine were obtained crystalline in 80 percent, 78 percent, 72 percent, 67 percent, and 65 percent yields, respectively.
Synthesis of 2'(3')-O-Aminoacyl Triribonucleoside Diphosphates Using the Triester Method
Kumar, Gyanendra,Celewicz, Lech,Chladek, Stanislav
, p. 634 - 644 (2007/10/02)
Specific syntheses of 2'(3')-O-aminoacyl triribonucleoside diphosphates, C-C-A-Phe (16e), C-C-A-Ala (16f), and C-C-A-Gly (16g), which are the terminal sequences of corresponding aa-tRNAs and potential substrates for ribosomal peptidyltransferase, are described.The compounds 16e-g were synthesized by employing phosphotriester methods with a benzoyl group for protection of heterocyclic amino groups, a 2-chlorophenyl group for internucleotide phosphate protection, a monomethoxytrityl group for blocking of the 5'-hydroxy function, a 4-methoxytetrahydropyranyl group forprotection of 2'-hydroxy functions, and an N-benzyloxycarbonyl group for blocking of the α-amino acid.Protected dinucleotide block C-Cp (11b) was synthesized via the triester method and was condensed by using mesitylenesulfonyl tetrazolide with nucleoside components 9b and 10b, which have aminoacyl residues incorporated in the molecule, to yield protected aminoacyl trinucleotides 13a and 14 in 60-70percent yields.The fully protected aminoacyl trinucleotides 13a and 13b were also obtained from the protected C-C-A derivative 12 (with a free 3'-OH group on the 3'-terminus) by the aminoacylation reaction with corresponding N-benzyloxycarbonyl amino acids and mesitylenesulfonyl tetrazolide in 50-70percent yields.The protected derivatives 13a,b and 14 were deblocked to form C-C-A(Z-Phe) (16b), C-C-A(Z-Ala) (16c), and C-C-A(Z-Gly) (16d) in 15-40percent yields by reactions with N2H4, F-, and H+ (for 16b,c) or NH4OH and H+ (for 16d).The final products 16e-g were prepared by hydrogenolysis (Pd/BaSO4) of 16b-d in practically quantitative yields.The syntheses of all components (3a,c,4,9a,b, and 10b) for the triester approach to aminoacyl trinucleotides are also described.
Synthesis of 2',3'-Differentiated Ribonucleosides via Glycosylation. Reactions with 2-O-Me or 2-O-TBDMS Ribofuranose Derivatives. 1. Pyrimidine Series
Chavis, C.,Dumont, F.,Wightman, R. H.,Ziegler, J. C.,Imbach, J. L.
, p. 202 - 206 (2007/10/02)
The synthesis of 2',3' asymmetrically substituted pyrimidine ribonucleosides in 70-95percent yields by using modified Vorbruggen conditions with "nonparticipating" 2-O-CH3 and 2-O-TBDMS ribofuranoses is described.Such compounds are useful synthons for oligoribonucleotide synthesis, including incorporation of "rare" bases.New and practically useful conditions for placement (using 1,2,4-triazole) and removal (KF/crown ether) of the tert-butyldimethylsilyl (TBDMS) protecting group are also reported.
