title: A strategy for selective N-acylation of purine and pyrimidine bases of deoxy and ribo nucleosides.
abstract: A novel cost effective N-acylation procedure for exocyclic amino function of ribonucleosides (adenosine/guanosine/cytidine) and deoxynucleosides (adenosine/guanosine/cytidine) has been developed. In the present method the acids used for acylation were activated by preparing their corresponding p-nitrophenyl esters. These esters couple with - NH(2) group in presence of dicyclohexylcarbodiimide as coupling agent and catalysts viz. DMAP, HOBT & HOSu to give the--CO-NH- bond; a well-established strategy in peptide synthesis. To minimise the contamination of DCU, different combinations of activated ester and nucleosides has been used. The use of catalysts viz. DMAP, HOBt & HOSu enhanced the yields. HOSu was found to give best results.
authors.affiliation: Nucleic Acids Research Laboratory, Department of Chemistry, University of Allahabad, University of Allahabad, Allahabad-211002, India.
authors.forename: Roli
authors.initials: R
authors.lastname: Mishra
authors.forename: Satyendra
authors.initials: S
authors.lastname: Mishra
authors.forename: Vishnu
authors.initials: V
authors.lastname: Diwedi
authors.forename: Krishna
authors.initials: K
authors.lastname: Misra
mesh_terms: D000215:Acylation; D000241:Adenosine / Q000138:chemical synthesis* / Q000737:chemistry; D003562:Cytidine / Q000138:chemical synthesis* / Q000737:chemistry; D003853:Deoxyribonucleosides / Q000138:chemical synthesis* / Q000737:chemistry; D006151:Guanosine / Q000138:chemical synthesis* / Q000737:chemistry; D011687:Purines / Q000737:chemistry; D011743:Pyrimidines / Q000737:chemistry
chemical_list: D003853:Deoxyribonucleosides; D011687:Purines; D011743:Pyrimidines; D006151:Guanosine; D003562:Cytidine; D000241:Adenosine