Concise Total Synthesis and Stereochemical Revision of all (−)-Trigonoliimines

The concise and enantioselective total syntheses of (−)-trigonoliimines A, B, and C are described. Our unified strategy to all three natural products is based on asymmetric oxidation and reorganization of a single bistryptamine, a sequence of transformations with possible biogenetic relevance. We revise the absolute stereochemistry of (−)-trigonoliimines A, B, and C

<i>N</i>-Isopropylidene-<i>N</i>‘-2-nitrobenzenesulfonyl Hydrazine, a Reagent for Reduction of Alcohols via the Corresponding Monoalkyl Diazenes

The reagent N-isopropylidene-N‘-2-nitrobenzenesulfonyl hydrazine (IPNBSH) is used in the reduction of alcohols via the loss of dinitrogen from transiently formed monoalkyl diazene intermediates accessed by sequential Mitsunobu displacement, hydrolysis, and fragmentation under mild reaction conditions

Concise Total Synthesis and Stereochemical Revision of all (−)-Trigonoliimines

The concise and enantioselective total syntheses of (−)-trigonoliimines A, B, and C are described. Our unified strategy to all three natural products is based on asymmetric oxidation and reorganization of a single bistryptamine, a sequence of transformations with possible biogenetic relevance. We revise the absolute stereochemistry of (−)-trigonoliimines A, B, and C

General Approach to Epipolythiodiketopiperazine Alkaloids: Total Synthesis of (+)-Chaetocins A and C and (+)-12,12′-Dideoxychetracin A

A highly stereoselective and systematic strategy for the introduction of polysulfides in the synthesis of epipolythiodiketopiperazines is described. We report the first total synthesis of dimeric epitri- and epitetrathiodiketopiperazines

Concise Total Synthesis and Stereochemical Revision of all (−)-Trigonoliimines

The concise and enantioselective total syntheses of (−)-trigonoliimines A, B, and C are described. Our unified strategy to all three natural products is based on asymmetric oxidation and reorganization of a single bistryptamine, a sequence of transformations with possible biogenetic relevance. We revise the absolute stereochemistry of (−)-trigonoliimines A, B, and C

Concise Total Synthesis and Stereochemical Revision of (+)-Naseseazines A and B: Regioselective Arylative Dimerization of Diketopiperazine Alkaloids

Concise and enantioselective total syntheses of (+)-naseseazines A and B are described. Our regioselective and directed dimerization of diketopiperazines provides their critical C3–Csp2 linkages, an assembly with plausible biogenetic relevance. We revise the absolute stereochemistry of (+)-naseseazines A and B

Concise Total Synthesis and Stereochemical Revision of all (−)-Trigonoliimines

The concise and enantioselective total syntheses of (−)-trigonoliimines A, B, and C are described. Our unified strategy to all three natural products is based on asymmetric oxidation and reorganization of a single bistryptamine, a sequence of transformations with possible biogenetic relevance. We revise the absolute stereochemistry of (−)-trigonoliimines A, B, and C

General Approach to Epipolythiodiketopiperazine Alkaloids: Total Synthesis of (+)-Chaetocins A and C and (+)-12,12′-Dideoxychetracin A

A highly stereoselective and systematic strategy for the introduction of polysulfides in the synthesis of epipolythiodiketopiperazines is described. We report the first total synthesis of dimeric epitri- and epitetrathiodiketopiperazines

Enantioselective Total Synthesis of Tricyclic Myrmicarin Alkaloids

An enantioselective gram-scale synthesis of a key dihydroindolizine intermediate for the preparation of myrmicarin alkaloids is described. Key transformations in this convergent approach include a stereospecific palladium-catalyzed N-vinylation of a pyrrole with a vinyl triflate, a copper-catalyzed enantioselective conjugate reduction of a β-pyrrolyl enoate, and a regioselective Friedel−Crafts reaction. The synthesis of optically active and isomerically pure samples of (4aR)-myrmicarins 215A, 215B, and 217 in addition to their respective C4a-epimers is presented

Single-Step Synthesis of Pyrimidine Derivatives

We describe a single-step conversion of various N-vinyl and N-aryl amides to the corresponding pyrimidine and quinazoline derivatives, respectively. The process involves amide activation with 2-chloropyridine and trifluoromethanesulfonic anhydride followed by nitrile addition into the reactive intermediate and cycloisomerization. In situ nitrile generation from primary amides allows for their use as nitrile surrogates. The use of this chemistry with sensitive N-vinyl amides and epimerizable substrates in addition to a wide range of functional groups is noteworthy