Current Organic Synthesis - Volume 11, Issue 5, 2014

Alkaloids isolated from the amphibian skin have shown interesting biological profiles especially relevant to neurology. The skin of the Ecuadorian frog tricolor has provided as a source for novel quinolizidine alkaloid epiquinamide, albeit in the minute quantities (240 µg from 183 frogs) representing a new class of nicotinic agonists in CNS disorders. Significant efforts have been devoted to the stereoselective synthesis of Read More

Triazoles and their derivatives have been widely utilized as precursors in the syntheses of biologically active systems such as anticancers, antimicrobials, antifungals and other cytotoxic active agents. In this review, we tried to highlight the recent advances (2010- 2013) in the syntheses of 1,2,3-triazoles, bis-1,2,3-triazoles and fused triazoles via click reaction. Click reaction provides substances quickly and reliably by com Read More

Aryl-fused 1,4-oxazine derivatives have been recently studied with growing interest due to their pesticidal, especially antifeedant and antifungal, as well as pharmacological activities. These promising biological properties have encouraged the development of efficient synthetic strategies toward 3,4-dihydro-2H-1,4-benzoxazines and their 2-oxo, 3-oxo and 2,3-dioxo derivatives. Most of the available methods for preparing these het Read More

The pseudo-trisaccharide allosamidin 1 is a potent inhibitor of all family 18 chitinases, and it is confirmed to have biological activities against insects and fungi. The solid/liquid phase syntheses of allosamidin 1 and its analogues have been developed in recent years, and these compounds can be obtained by iterative glycosylation reactions, catalytic hydrogenation, acetylation, deacetylation, or photolysis, respectively.

Quinolines as one of the most important classes of heterocyclic compounds are widely present as key structural motifs in many natural products, particularly in alkaloids and numerous bioactive drugs. Various name reactions for the syntheses of quinolines such as Skraup, Camps, Combes, Conrad-Lympach, Knorr, Gould-Jacobs, Povarov, Doebner and Doebner-von Miller, Pfitzinger and Niementowski, and Friedländer have alr Read More

Organic chemists utilize azide synthons to generate a wide variety of functionalities, such as triazoles, tetrazoles, and diazo compounds. Though these products are often pharmacophores for biologically active molecules, the potentially hazardous nature of azides can act as a deterrent to their use in conventional reaction settings as they and diazo compounds are both explosive and toxic. Consequently, safer and greener Read More

The solvent effect of different imidazolium, phosphonium and quaternary ammonium based ionic liquids was studied for the synthesis of amidoximes, demonstrating enhanced selectivity when using IL’s as the reaction medium.

Three benzylated triazole-linked nonionic locked nucleoside dimers TL-t-TL, TL-t-ABzL and TL-t-CBzL have been synthesized by Cu(I) catalyzed Huisgen-Sharpless-Meldal [3+2] cycloaddition reaction of 3'-azido-3'-deoxy-2'-O,4'-C-methylenethymidine with 3'-Obenzyl- 5'-deoxy-5'-C-ethynyl-2'-O,4'-C-methylenethymidine, 3'-O-benzyl-5'-deoxy-5'-C-ethynyl-2'-O,4'-C-methylene-6-N-benzoyladenosine and 3'-O-benzyl-5'-deoxy-5'-C- Read More

Alkyl phenyl-H-phosphinates were synthesized by microwave(MW)-assisted direct esterification of phenyl-H-phosphinic acid. The phosphinates were then oxidized by m-chloroperbenzoic acid to the corresponding phenylphosphonic ester-acids that were esterified further under MW conditions to afford dialkyl phenylphosphonates. This is the first case that a mixed phosphonic derivative was esterified directly that is possible only un Read More

In this work we report the highly efficient solvent-free and self-catalyzed three-component approach for the synthesis of pyrazolo[ 3,4-e][1,4]thiazepin-7(4H)-ones. The reaction between 5-aminopyrazoles, benzaldehydes and mercaptoacetic acid, acting both as reagent and catalyst, at 120 °C lead to the sequential formation of three new single bonds and the release of water as unique by-product, which demonstrate Read More