- N8-Glycosylated 8-Azapurine and Methylated Purine Nucleobases: Synthesis and Study of Base Pairing Properties
-
In this report, we present the synthesis of N8-glycosylated 8-aza-2-methylhypoxanthine and 8-aza-6-thiohypoxanthine 2′-deoxynucleosides as well as methylated 2′-deoxynebularine derivatives. In vitro base pairing properties between each modified and canonical nucleobase were studied. As demonstrated by Tm, incorporation of the modified bases in DNA resulted, with few exceptions, in low stability of duplexes. Modified bases studied in this report are preferentially recognized by T (for N8-glycosylated 8-aza-2-methylhypoxanthine and methylated purines) and G (N8-glycosylated 8-aza-2-methylhypoxanthine). The base pair formed between N8-glycosylated 8-aza-6-thiohypoxanthine and N9-glycosylated 2-methyl-6-thiohypoxanthine (X2:X6) showed, to some extent, an orthogonal interaction. Based on Tm studies, the only potential self-pairing system is formed by the N8-glycosylated 8-aza-6-thiohypoxanthine nucleoside (X2) but only in the absence of canonical G and T. This study indicated that the canonical thymine base is the preferential base partner of methylated purine bases.
- Leonczak, Piotr,Srivastava, Puneet,Bande, Omprakash,Schepers, Guy,Lescrinier, Eveline,Herdewijn, Piet
-
p. 13394 - 13409
(2019/11/03)
-
- DEAMINATION, INVOLVING RING OPENING, IN REACTIONS OF 1-AMINOPURINIUM MESITYLENESULFONATES WITH METHANOLIC AMMONIA
-
On reaction of 1-aminopurinium mesitylenesulfonates with methanolic ammonia N-deamination occurs.For 1-amino-, 1-amino-8-(methylthio)-, 1-amino-8-phenyl-, 1-amino-2-methyl-, 1-amino-6-methyl- and 1-amino-8-phenyl-9-methylpurinium mesitylenesulfonate this reaction proceeds for at least 75percent via ring opening as shown by the isolation of 1-15N-labelled purines when 15N-labelled methanolic ammonia was used. 1-Amino-9-methylpurinium mesitylenesulfonate gave N-deamination without ring opening.The reaction of 1-amino-6-(methylthio)purinium mesitylenesulfonate with methanolic ammonia involves, besides deamination, partial substitution of the methylthio group; no ring opening is involved.However, ring opening followed by substitution occurs in the reaction of 1-amino-2-(methylthio)purinium mesitylenesulfonate; the reaction proceeds via an adduct at position 2.
- Kos, N. J.,Jongejan, H.,van der Plas, H. C.
-
p. 4841 - 4848
(2007/10/02)
-