Caffeine and Purine Derivatives: A Comprehensive Review on the Chemistry, Biosynthetic Pathways, Synthesis-Related Reactions, Biomedical Prospectives and Clinical Applications.

Caffeine and purine derivatives represent interesting chemical moieties, which show various biological activities. Caffeine is an alkaloid that belongs to the family of methylxanthine alkaloids and it is present in food, beverages, and drugs. Coffee, tea, and some other beverages are a major source of caffeine in the human diet.

Synthesis and Anticancer Activity of Novel Chromene Derivatives, Chromeno[2,3-d][1,3]Oxazines, and Chromeno[2,3-d]Pyrimidines.

Background: Several chromene derivatives have a wide variety of biological and pharmacological activity. They had anticancer activity, antimicrobial activity, antituberculosis activity, anticonvulsant activity, antidiabetic activity, antichlolinesterase activity, and inhibitor of monoamine oxidase activity. The above-mentioned activities directed us to synthesize novel chromene derivatives, chromeno[2,3-d][1,3]oxazines, and chromeno[2,3-d]pyrimidines.

Novel allyl-hydrazones including 2,4-dinitrophenyl and 1,2,3-triazole moieties as optical sensor for ammonia and chromium ions in water.

It is critical to take safety action if carcinogenic heavy metals and ammonia can be detected quickly, cheaply, and selectively in an environmental sample. As a result, compound 4a [4-(1-(2-(2,4-Dinitrophenyl)hydrazineylidene)-3-(naphthalen-2-yl)allyl)-5-methyl-1-phenyl-1 H-1,2,3-triazole] and compound 4b [4-(1-(2-(2,4-Dinitrophenyl)hydrazineylidene)-3-(naphthalen-2-yl)allyl)-1-(4-fluorophenyl)-5-methyl-1 H-1,2,3-triazole] were prepared. The aldol condensation process of 4-acetyl-1,2,3-triazoles 1a,b (Ar = CH; 4-FCH) with 2-naphthaldehyde yields 1-acetyl-1,2,3-triazoles 1a,b (Ar = CH; 4-FCH) (5-methyl-1-aryl-1 H-1,2,3-triazol-4-yl) -3-(naphthalen-2-yl)prop-2-en-1-ones 3a,b with a yield of around 95%.

Interaction of small molecules with polynucleotide repeats and frameshift site RNA.

This mini-review describes the interaction between small molecules and RNA, in addition to its application either in treating RNA-associated diseases or detecting target molecules. In the case of RNA-associated disease treatment, the designed small molecules interact with RNA sites, forming adducts and providing successful therapeutic strategies over oligonucleotides. On the other hand, synthetically designed RNA moieties (aptamers) interact with target molecules like toxins, drugs, hormones; these interactions are useful in the detection, quantification or separation of these target moieties.