The synthesis of 5-carboxamido-4-hydroxy-3-(β-D-ribofuranosyl)-thiophene derivatives, analogues of pyrazofurin

Synthesis and antioxidant evaluation of some new sulphadimidine incorporating thiophene moiety

“…Some sulphadrugs have been used in the treatment of cancer, malaria, leprosy and tuberculosis [2,3]. Moreover, many thiophene derivatives were reported to exhibit different biological properties, such as A1 adenosine receptor, allosteric enhancers [4,5], inhibitors of Human Leukocyte Elastase [6,7], antitumor [8], virucides, virostatic agent, [9], antitumor and anti-HIV activities [4]. Different methods were reported for the syntheses of azo sulphadrugs [10][11][12][13][14][15].…”

Synthesis of new iso-C-nucleoside analogues from 2-(methyl 2-O-benzyl-4,6-O-benzylidene-3-deoxy-α-d-altropyranosid-3-yl)ethanal

“…4,6-O-Benzylidene-3-deoxy-3-(prop-2-enyl)-a-D D-altropyranoside (2) was prepared in 80% yield by treatment of methyl 2,3-anhydro-4,6-O-benzylidene-a-D D-mannopyranoside (1) with allylmagnesium bromide (Scheme 1). 20,21 Benzylation of the 2-hydroxy group in THF with benzyl bromide and sodium hydride in the presence of tetrabutylammonium iodide 22,23 gave the branchedchain sugar 3.…”

“…1 The corresponding 5-carboxamido-4-hydroxy-3-(b-D D-ribofuranosyl)thiophene-2-carbonic acid derivatives were investigated as virucides and virostatic agents. 2 Furthermore, thieno [2,3-d]pyrimidine derivatives 3 showed interesting biological properties including antihypertensive, 4 antiallergenic, 5 antitumour, 6 antiviral, 6 anti-HIV-1 6 and analgesic 7 activities. A few examples of thieno [2,3-d]pyrimidine nucleosides are known.…”

Chemistry of α-Oxoesters: A Powerful Tool for the Synthesis of Heterocycles

“…488 Also, 3-ribofuranosyl-substituted 4-hydroxythiophene 980 was synthesized by a similar reaction between dimethyl thiodiacetate and ribofuranosyl-2-oxoacetate 951 in the presence of NaOMe in MeOH at 20°C during 60 h, in 40% yield, as a mixture of triand disilylated products 980a/980b in a ratio of 24/16 (Scheme 322b). 472 The Gewald reaction on solid support was developed between an activated nitrile compound and ethyl 2-oxo-4-phenylbutanoate in the presence of S 8 and morpholine, to afford aminothiophene 981. Reaction was performed in EtOH under reflux conditions for 8 h. By acetylation of the amine group, followed by cleavage of Wang resin solid support using T F A i n D C M / w a t e r , 2 -a c e t a m i d o -5 -b e n z y l -4 -(ethoxycarbonyl)thiophene-3-carboxylic acid 982 was obtained in 34% yield, and 87% purity (Scheme 323).…”