Current Organic Chemistry - Volume 18, Issue 1, 2014

Quinone methides (QMs) are important intermediates in chemistry and biochemistry of phenols that are characterized by wide biological activity. Some classes of anticancer antibiotics exhibit their effect due to methabolic formation of QMs that alkylate DNA. Photochemical reactions provide mild and easy approach to QMs. Photoreactions that give QMs include cleavage of oxa-heterocycles, dehydrohalogenation, dehydration, Read More

The following review analyzes the most effective activation protocols for the generation of transient electrophilic quinone methides, merged into the recent strategies to achieve recognition and alkylation of nucleic acids. The covalent targeting has to be specific for selected oligonucleotide sequences (sequence-specificity) or for those oligonucleotides capable to fold into supramolecular structures, such as G-quadruplexes (s Read More

In this review, we discuss the advances in understanding the reactivity of quinone methide (QM) intermediates and the reversibility of DNA alkylation by QMs in the past two decades. QMs react with strong nucleophiles of DNA under kinetic control but reversibly. The effective lifetime of QMs can be extended through repeated capture and release from DNA adducts. A QM-acridine conjugate DNA cross-linking agent remai Read More

The formation of quinone methides (QMs) from either direct 2-electron oxidation of 2- or 4-alkylphenols, isomerization of oquinones, or elimination of a good leaving group could explain the cytotoxic/cytoprotective effects of several drugs, natural products, as well as endogenous compounds. For example, the antiretroviral drug nevirapine and the antidiabetic agent troglitazone both induce idiosyncratic hepatotoxicity through Read More

Quinone methides (QMs) are naturally occurring reactive intermediates which play important roles in organic syntheses as well as in a large number of chemical and biological processes. QMs are also believed to be responsible for the ultimate cytotoxicity of many antitumor drugs, antibiotics, and DNA alkylators through enzyme inhibition or DNA alkylation. Many different chemical methods have been developed to s Read More

Bioorthogonal ligations have found widespread use in biomedical research for site selective labeling of biomolecules in living systems. Discovering new reactions to expand the toolbox of bioorthogonal chemistry remains an important, yet challenging task as most reactions do not meet the stringent requirements of bioorthogonal reaction. As highly useful synthetic intermediates, ortho-quinone methides (oQMs) have been b Read More

Homochirality and related problems have been reviewed. Relative probability of different versions of homochirality arising were estimated on the example of processes, synthesis of organic compounds in space, asymmetric photolysis under circularly polarized light, synthesis of optically active compounds as a result of parity violation, magnetochiral dichroism, chiral amplification, optical active amino acids synthesis and theirs is Read More

Pyrazoles are compounds of synthetic origin, and constitute a group of nitrogen heterocyclic compounds that have shown several biological activities. Their transformations into other biologically active molecules have been exploited since the early 1960s. This review describes the work on the environment-friendly synthesis of bioactive pyrazoles. The review covers mainly the data published over the last five years (2007–2012).

Conformationally rigid phosphoric acids derived from suitably substituted axially dissymmetric 1,1’-bi-2,2’-naphthol (BINOL) find wide application in organic synthesis. These chiral Brønsted acids are able to catalyze enantioselective transformations of electrophilic imines with both carbon-centered and other hetero nucleophiles to generate enantioenriched products of academic, industrial and biological significance. Select Read More