Reactions of 5-bromo-6-methoxy-5,6-dihydrouridine and its 2-thioanalogue with both of some guanidines and mercapto acrylicacid derivatives

5-bromo-6-methoxy-5,6-dihydrouridine and its 2-thioanalogue were allowed to react with some substituted guanidine tautomers and alpha- mercapto-beta-phenylacrylic acid. The products are 5,6-cyclized derivatives of both of uridine and 2-thiouridine

Reactions of uridine and 4-thiouridine derivatives with some-halo esters

Uridine and 4-thiouridine were converted into the corresponding 2,3-o-isopropylidene-5-thiocyanato derivatives. Then, each resulted derivative was reacted individually with both of ethyl alpha- chloroacetoacetate, ethyl alpha-bromobenzoylacetate and ethyl bromo pyruvate. Furthermore, these 5-thiocyanato products were transformed into the corresponding 5-mercapto analogues. The produced analogues were undergo ring formation to give the corresponding 4,5-cyclized pyrimidine derivatives

Synthesis of some uridine and cytidine derivatives

Some modified nucleosides were prepared from 5,6-disubstituted uridine, 5-substituted cytidine and cytidine. Different nucleophilic substitution reactions were carried out in alkaline or neutral medium. Some of these reactions describe ring formation

Some important uridine reactions

The presented study concern some reactions on the 5-position of uridine, such as reaction of 2',3'-O-isopropylidene uridine with 5-bromofuran-2-carbaldehyde. The reactions of uridine with thioaldehydes are a cycloaddition reactions. Furthermore, reaction of uridine with thiobenzoic acid is an addition reaction on the 5, 6 double bond of the heterobase. Nucleophilic substitution of the thiobenzoyl group of the resulting product by ethyl of t-butyl glycine esters was performed

Cycloaddition reactions with both of uridine and 2-thiouridine derivatives

The present paper described work directed towards reactions of both of 2',3',5'-tri-O-acetyl uridine and its 2-thioanlogue with either of 2H- pyran-2-one, 4,6-dimethyl-2H-pyran-2-one and 2,3-bis [dibromomethyl] benzene to afford cycloaddition products

Synthesis of some aminonaphthalene and 5-substituted uracil nucleosides derivatives

Some amino naphthalene nucleosides were prepared by the reaction of both of 1-amino, 1-aminomethyl, 1,5-diamino and 2,6-bis [aminomethyl] naphthalene derivatives with 2,3,5-tri-O-acetyl ribofuranosyl chloride. On the other hand, the reactions of 2',3'-O-isopropylidene 5-amino uridine and its 5-aminomethyl analogue with gluconolactone and the reactions of 2',3'-O-isopropylidene-5-chloromethyl uridine with sodium N-methyl taurinate have been described

Synthesis of some cytidine derivatives

Synthesis of some cytidine derivatives involving 4,5 cyclisation are performed by the individual reactions of both of 5-hydroxy, 5-mercapto and 5-amino cytidines with chloroethyl formate, thionyl chloride and thiophosgene successively. On the other hand, reactions of cytidine with chloroacetone or chloropropionaldehyde give 3,4-cyclized cytidine products