Cofactor-mimetic aerobic oxidation has conceptually merged with catalysis of syngas reactions to form a wide range of Markovnikov-selective olefin radical hydrofunctionalizations. We cover the development of the field and review contributions to reaction invention, mechanism, and application to complex molecule synthesis. We also provide a mechanistic framework for understanding this compendium of radical reactions.

/pdf/mn-fe-and-co-catalyzed-radical-hydrofunctionalizations-of-3ukqn8iif4.pdf

Mn-, Fe-, and Co-Catalyzed Radical Hydrofunctionalizations of Olefins

New and selective ryanodine receptor activators for insect control.

The goal of this review has been to describe the current state of the pharmacology of ryanodine and related compounds relative to the vertebrate RyRs. Resolution of questions concerning the molecular properties of RyR channel function and the contributions made by the RyR isoforms to cellular signaling in a variety of tissues will require the production of new pharmacological agents directed against these proteins. Novel naturally occurring ryanodine congeners have been identified, and significant advances have been made in developing chemical approaches that permit the structure of ryanodine to be derivatized in selective ways. Moreover, several of these changes have yielded compounds that differ in their binding affinities and in their abilities to modify the properties of the RyR channels. These advances give substance to the possibility of designing the required pharmacological agents based on rational design changes of the structure ryanodine.

The Pharmacology of Ryanodine and Related Compounds

The pool of abundant chiral terpene building blocks (i.e., “chiral pool terpenes”) has long served as a starting point for the chemical synthesis of complex natural products, including many terpenes themselves. As inexpensive and versatile starting materials, such compounds continue to influence modern synthetic chemistry. This review highlights 21st century terpene total syntheses which themselves use small, terpene-derived materials as building blocks. An outlook to the future of research in this area is highlighted as well.

Navigating the Chiral Pool in the Total Synthesis of Complex Terpene Natural Products

First-row transition-metal-mediated reactions constitute an important and growing area of research due to the low cost, low toxicity, and exceptional synthetic versatility of these metals Currently, there is considerable effort to replace existing precious-metal-catalyzed reactions with first-row analogs More importantly, there are a plethora of unique transformations mediated by first-row metals, which have no classical second- or third-row counterpart Herein, the application of first-row metal-mediated methods to the total synthesis of natural products is discussed This Review is intended to highlight strategic uses of these metals to realize efficient syntheses and highlight the future potential of these reagents and catalysts in organic synthesis

Methods Utilizing First-Row Transition Metals in Natural Product Total Synthesis.

-Pyrrolecarboxylate ester the active insecticidal component in the roots and stems of Ryana speciosa; binds nearly irreversibly to sarcoplasmic reticulum vesicles; binding studies intentified calcium release channels now known as Ryanodine receptors -Originally reported in 1948 by collaborators from Merck and the Department of Entomology at Rutgers University -In 1967, Wiesner and co-workers elucidated the full structure 2 of natural ryanodine -The X-ray structure of the p-bromobenzyl ether 3 of ryanodol was reported in 1972

Total synthesis of ryanodol

Treatment of vinyl acetate with ozone yields the mixed anhydride of acetic and formic acids and formaldehyde oxide. The formaldehyde oxide can be trapped by reaction with ketones yielding the corre...

H.-Jürg Borschberg

Papers

Total synthesis of ryanodol

Thermal decomposition of ozonides. A complementary method to the Baeyer–Villiger oxidation of hindered ketones