177949-02-9Relevant articles and documents
Synthesis of 5-phenyl-2(1H)-pyrimidinone nucleosides
Krecmerova, Marcela,Hrebabecky, Hubert,Masojidkova, Milena,Holy, Antonin
, p. 458 - 477 (1996)
Reaction of 2-phenyltrimethinium salt 1 with thiourea and subsequent reaction with chloroacetic acid afforded 5-phenyl-2(1H)-pyrimidinone (3). Its silyl derivative 4 was condensed with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose under catalysis with tin tetrachloride or trimethylsilyl trifluoromethanesulfonate to give protected nucleoside 5 together with 5′,O 6-cyclo-5-phenyl-1,3-bis-(β-D-ribofuranosyl)-6-hydroxy-5,6- dihydro-2(1H,3H)-pyrimidinone (7). The greatest amounts of 7 were formed with the latter catalyst. Nucleosidation of the silyl derivative 4 with protected methyl 2-deoxy-D-ribofuranoside 8 or 2-deoxy-D-ribofuranosyl chloride 9 afforded 1-(2-deoxy-3,5-di-O-p-to-luoyl-β-D-ribofuranosyl)-5-phenyl-2(1H)- pyrimidinone (10) and its α-anomer 11. Reaction of 10 and 11 with methanolic ammonia gave free 2′-deoxynucleosides 12 and 13. Compound 13 was converted into 5′-O-tert-butyldiphenylsilyl-3′-O-mesyl derivative 14 which on heating with 1,8-diazabicydo[5.4.0]undec-7-ene (DBU) and subsequent cleavage with tetrabutylammonium fluoride afforded 2′,3′-dideoxy-2′,3′-didehydronucleoside 15. Reaction of the silyl derivative 4 with 1,2-di-O-acetyl-3,5-di-O-benzoylxylofuranose (18), catalyzed with tin tetrachloride, furnished 1-(2-O-acetyl-3,5-di-O-benzoyl-β-D-xylofuranosyl)-2(1H)-pyrimidinone (19) which was deprotected to give the β-D-xylofuranosyl derivative 22. As a side product, the nucleosidation afforded the β-D-xylopyranosyl derivative 23. Deacetylation of compound 19 gave 1-(3,5-di-O-benzoyl-β-D-xylofuranosyl)-5-phenyl-2(1H)-pyrimidinone (24) which on reaction with thionyl chloride afforded 2′-chloro-2′-deoxynucleoside 25 and 2′,O6-cyclonucleoside 26. Heating of compound 25 with DBU in dimethylformamide furnished the lyxo-epoxide 27 which on reaction with methanolic ammonia was converted into free 1-(2,3-anhydro-β-D-lyxofuranosyl)-5-phenyl-2(1H)-pyrimidinone (28). Reaction of 1,2-di-O-acetyl-5-O-benzoyl-3-O-methanesulfonyl-D-xylofuranose (30) with silyl derivative 4 gave the nucleoside 31 which by treatment with DBU was converted into an equilibrium mixture of 5′-benzoylated arabinofuranoside 33a and its 2′,6-anhydro derivative 33b.
