87875-17-0

Upstream product

• 20264-96-4 2-(4-nitrophenyl)ethyl iodide 
• 87875-11-4 2',3'-di-O-benzoyl-5'-O-monomethoxytrityluridine 
• 100-27-6 2-(4-nitrophenyl)ethanol 
• 20264-95-3 2-(4-nitrophenyl)ethyl chloride 

Downstream Products

• 87875-24-9 C₅₇H₅₉Cl₂N₄O₁₄PSi 
• 87875-27-2 Phosphoric acid (2R,3R,4R,5R)-4-(tert-butyl-dimethyl-silanyloxy)-2-hydroxymethyl-5-{4-[2-(4-nitro-phenyl)-ethoxy]-2-oxo-2H-pyrimidin-1-yl}-tetrahydro-furan-3-yl ester 2,5-dichloro-phenyl ester 2-(4-nitro-phenyl)-ethyl ester 
• 87875-20-5 1-{(2R,3R,4R,5R)-3-(tert-Butyl-dimethyl-silanyloxy)-4-hydroxy-5-[(4-methoxy-phenyl)-diphenyl-methoxymethyl]-tetrahydro-furan-2-yl}-4-[2-(4-nitro-phenyl)-ethoxy]-1H-pyrimidin-2-one 
• 87875-28-3 1-{(2R,3R,4S,5R)-4-(tert-Butyl-dimethyl-silanyloxy)-3-hydroxy-5-[(4-methoxy-phenyl)-diphenyl-methoxymethyl]-tetrahydro-furan-2-yl}-4-[2-(4-nitro-phenyl)-ethoxy]-1H-pyrimidin-2-one 
• 87875-26-1 Phosphoric acid (2R,3R,4R,5R)-4-(tert-butyl-dimethyl-silanyloxy)-2-[(4-methoxy-phenyl)-diphenyl-methoxymethyl]-5-{4-[2-(4-nitro-phenyl)-ethoxy]-2-oxo-2H-pyrimidin-1-yl}-tetrahydro-furan-3-yl ester 2-(4-nitro-phenyl)-ethyl ester; compound with triethyl-amine 
• 87875-11-4 2',3'-di-O-benzoyl-5'-O-monomethoxytrityluridine 
• 87875-19-2 5'-O-monomethoxytrityl-O⁴-p-nitrophenylethyluridine 

Relevant academic research and scientific papers

THE p-NITROPHENYLETHYL (NPE) GROUP. A VERSATILE NEW BLOCKING GROUP FOR PHOSPHATE AND AGLYCONE PROTECTION IN NUCLEOSIDES AND NUCLEOTIDES

The syntheses of new monomeric building blocks for oligonucleotide synthesis via the phosphotriester approach containing the p-nitrophenylethyl group for phosphate and aglycone protection are described.Blocking of the amide function in guanosines at O6 can be achieved by the Mitsunobu reaction forming the corresponding O6-p-nitrophenylethyl derivatives (4,5,10).Sugar-protected thymidine (16) and uridine (17) have been alkylated at O4 in an SN1-type reaction by p-nitrophenylethyl iodide-silver carbonate in benzene to form the O4-p-nitrophenylethyl derivatives (18,19).Protection of the amino group in 2'-deoxycytidine (25) and cytidine (26) can be performed directly by 1-(p-nitrophenylethoxycarbonyl)-benzotriazole in DMF to obtain the corresponding carbamates (27,28) as a new type of N4-acylated cytidine derivative. p-Nitrophenylethoxycarbonylation of the amino group in 2'-deoxyadenosine (33) and adenosine (34) requires previous sugar protection by acyl or silyl groups and can then be achieved by p-nitrophenylethyl chloroformate or better by 1-methyl-3-p-nitrophenylethoxycarbonylimidazolium chloride to form N6-p-nitrophenylethoxycarbonyladenosines (38,39,40,42).The various p-nitrophenylethyl blocking groups are stable under mild hydrolytic conditions (e.g. ammonia and triethylamine) but can be cleaved selectively by DBU or DBN in aprotic solvents. 5'-O-Monomethoxytritylation (12,29,43) as well as phosphorylations at the 3'-OH group can be effected to give the corresponding 3'-(2,5-dichlorophenyl,p-nitrophenylethyl)-phosphotriesters (13,22,30,44) also in high yields.Oximate cleavage of the latter compounds to the phosphodiesters (14,24,32,46) and detritylation to the 5'-unblocked phosphotriesters (15,23,31,45) do not affect the aglycone protecting groups, thereby demonstrating their general versatility.The newly synthesized compounds have been characterized on the basis of their elementary analyses (C,N,H), and UV- and 1H-HMR-spectra.

SYNTHESIS OF O4-p-NITROPHENYLETHYL THYMIDINE AND URIDINE DERIVATIVES

O4-Protection in thymidine and uridine derivatives has been achieved by the p-nitro-phenylethyl group in a silver-ion catalysed alkylation reaction to form valuable building blocks for oligonucleotides syntheses.