M., Solid-phase synthesis of C-terminally modified peptides.

Synthesis of Enantiomerically Pure α-[4-(1-Substituted)-1,2,3-triazol-4-yl]-benzylacetamides via Microwave-Assisted Click Chemistry: Towards New Potential Antimicrobial Agents.

S., A new solvent system for efficient synthesis of 1,2,3-triazoles.

Synthesis of New Tetrazole and Triazole Substituted Pyroglutamic Acid and Proline Derivatives.
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K., New methods for the synthesis of heterocyclic compounds.

These unique materials are produced by plants throughout the world as phytoalexins, serving as a first line of chemical defense against stresses such as fungal infections. That role may derive from the fact that these molecules, including 8–20 (), can be formed readily from resveratrol (4) through its self-merger anywhere between two, and upwards of ten, times through numerous distinct C-C and C-O bond constructions. Indeed, to put that bond-forming diversity into perspective, most other similarly-produced oligomer families have just one or two specific combination modes. Although the biogenesis of this family remains an open question, a number of studies,, point to a reasonable hypothesis based on two main phases of construction, stages that could be viewed as similar to the cyclase and oxidase paradigm of terpene biosynthesis., In the first, radical and/or cation-based reaction cascades convert resveratrol (4) into multiple dimeric frameworks, including 8–15. These cores may result either through direct dimerization of 4 or rearrangement reactions of a given dimer (especially ε-viniferin, 8) into additional frameworks under appropriate conditions to create an initial base of architectural and stereochemical diversity., Whether enzymes are involved in these processes is unknown, though the participation of some chiral entity at some stage seems reasonable given that many of these materials are isolated in an optically active form.

O., Synthesis of new heterocyclic fatty compounds.

From these staging areas, further oligomerization can occur in a second synthesis stage, with one seemingly prevalent mode being the addition of new resveratrol units to generate dihydrofuran rings. As indicated by the representative structures shown for compounds 16–20- derived from the pallidol (12) and ampelopsin F (14) cores, these new ring systems are added with inconsistent regio- and stereospecificity. Though it is unknown the degree to which a given plant species can dictate the synthetic distribution of these variants (and again whether enzymes are even involved in such processes), from a global perspective the possibility of concurrently garnering such diversity is likely advantageous since it affords a broader range of architectures and potential biochemical properties. Indeed, initial screens have shown that activity is correlated with both size and stereochemistry. For example, while resveratrol (4) possesses broad spectrum activity in murine models (and is implicated in the “French paradox” in humans),, the addition of increasing numbers of resveratrol units affords compounds with greater specificity and potency.,, Similarly, while ampelopsin H (17) and nepalensinol B (20) have the same cores, their stereochemical differences lead to different mechanisms of anti-cancer activity.,

Design, Synthesis, and Preliminary Biological Evaluation of a Novel Triazole Analogue of Ceramide.
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A New Synthesis of Flavonoids via Heck Reaction

To put the developed approach for the resveratrol class in strategic context, it reflects a hybrid of retrosynthetic analysis and divergent/diversity-oriented synthesis,, a combination that could be argued as obvious in terms of the bond connections desired, but non-obvious in terms of the tools needed to execute those reactions (particularly positionally-selective transforms). Whether or not this overall strategy can be extended to the synthesis of other oligomer families remains to be established. What is certain is the evaluation of that question will offer many opportunities for reagent and reaction discovery, particularly as more complex brominative functionalizations are evaluated with natural products, compounds pertinent to materials research, and building blocks needed for pharmaceuticals.

A new synthesis of 4′-resveratrol esters and evaluation …

K., Novel nitrogen containing chelating ligands from aziridines - preparation, coordination studies, and catalytic application in the cyclopropanation of styrene.

A new synthesis of resveratrol 【Chemsrc】

Synthesis of DOTA-Conjugated Multivalent Cyclic-RGD Peptide Dendrimers via 1,3-Dipolar Cycloaddition and their Biological Evaluation: Implications for Tumor Targeting and Tumor Imaging Purposes.