Nucleosides with self-complementary hydrogen-bonding motifs: Synthesis and base-pairing studies of two nucleosides containing the imidazo[4,5-d]pyridazine ring system

Azolo[d]pyridazinones in medicinal chemistry

Azolo[d]pyridazinone is a privileged structure and versatile pharmacophore whose derivatives are associated with diverse biological activities, in particular antidiabetic, antiasthmatic, anticancer, analgesic, anti-inflammatory, antithrombotic, antidepressant and antimicrobial activities. The importance of this scaffold against some targets like PDE, COX and DPP-4 has been reviewed in detail previously. In the present review, we have summarized comprehensive information on azolo[d]pyridazinone derivatives investigated by many researchers for their diverse pharmacological activities, structure-activity relationship and molecular modeling studies since 2000. The review may lead scientists in the research fields of organic synthesis, medicinal chemistry and pharmacology to the strategic design and development of azolo[d]pyridazinone-based drug candidates in the future.

An expedient synthesis of flexible nucleosides via a regiocontrolled enzymatic glycosylation of functionalized imidazoles

A versatile two-step synthesis of C4- and C5-arylated 2′-deoxyribosylimidazoles was elaborated by enzymaticN-transglycosylation followed by microwave-assisted Pd-catalysed arylation reactions.

Synthesis of purine modified 2'-C-methyl nucleosides as potential anti-HCV agents

Based on the anti-hepatitis C activity of 2'-C-methyl-adenosine and 2'-C-methyl-guanosine, a series of new modified purine 2'-C-methyl nucleosides was prepared as potential anti-hepatitis C virus agents. Herein, we report the synthesis of both 6-modified and 2-modified purine 2'-C-methyl-nucleosides along with their anti-HCV replication activity and cytotoxicity in different cells.

Unnatural nucleosides with unusual base pairing properties

Synthetic modified nucleosides designed to pair in unusual ways with natural nucleobases have many potential applications in biology and biotechnology. This overview lays the foundation for future protocol units on synthesis and application of unnatural bases, with particular emphasis on unnatural base analogs that mimic natural bases in size, shape, and biochemical processing. Topics covered include base pairs with alternative H-bonding schemes, dimensionally expanded base pairs, hydrophobic base pairs, metal-ligated bases, degenerate bases, universal nucleosides, and triplex constituents.