An efficient synthesis of N3,4-diphenyl-5-(4-fluorophenyl)-2-isopropyl-1H-3-pyrrolecarboxamide, a key intermediate for the synthesis of an effective HMG-CoA reductase inhibitor atorvastatin, is described. The synthesis is based on the 1,3-dipolar cycloaddition reaction of mesoionic munchnone (1,3-oxazolium-5-olate) with N1,3-diphenyl-2-propynamide leading to N-benzyl pyrrole, and N-debenzylatio...

It is known that ammonium azides are both effective and convenient azidation agents, which are widely used in the syntheses of tetrazoles in media of aprotic dipolar solvents. However, until the present time, information about using these reagents for the synthesis of the 1,2,3-triazoles has been absent. In this case, alkali metal azides as well as trimethylsilyzide are the best known azidation...

Using a highly effective binuclear Cu complex as the catalyst, the 1,3-dipolar cycloaddition reactions between 16 alkynes and two azides were successfully performed and resulted in the production of 25 new triazole-containing sorafenib analogs. Several compounds were evaluated as potent antitumor agents. Among them, 4-(4-(4-(3-fluorophenyl)-1H-1,2,3-triazol-1-yl)phenoxy)-N-methylpicolinamide (8...

The first enantioselective total synthesis of the epipolythiodiketopiperazine (ETP) natural product (-)-acetylapoaranotin (3) is reported. The concise synthesis was enabled by an eight-step synthesis of a key cyclohexadienol-containing amino ester building block. The absolute stereochemistry of both amino ester building blocks used in the synthesis is set through catalytic asymmetric (1,3)-dipo...

The first N-heterocyclic carbene (NHC)-catalyzed [3+4] cycloaddition of azomethine imines and enals is disclosed. Oxidative catalytic remote activation of enals affords 1,4-dipolarophile intermediates that react with 1,3-dipolar azomethine imines to generate dinitrogen-fused seven-membered heterocyclic products with high optical purities. Our approach also provides effective kinetic resolution ...

Drug-like spirocyclic scaffolds have been prepared by fusing fully functionalized pyrrolidine with oxindoles in an approach based on 1,3-dipolar cycloaddition. Reaction between aziridine and 3-ylideneoxindole generated diverse spirooxindole-pyrrolidines in good yield (up to 95%) with high diastereoselectivity (up to >20:1). The reaction also proceeded smoothly with several other synthetically u...

A series of hitherto unreported anthracene-embedded dispirooxindoles has been synthesized via a one-pot three-component 1,3-dipolar cycloaddition reaction of an azomethine ylide, generated in situ from the reaction of isatin and sarcosine to 10-benzylideneanthracen-9(10H)-one as a dipolarophile in 1-butyl-3-methylimidazolium bromide([bmim]Br), an ionic liquid. This reaction proceeded regio- and...

Conjugated nitroalkenes and nitrodienes undergo smooth α-hydrazination with azodicarboxylates through an imidazole catalyzed carbon-heteroatom bond formation under Morita-Baylis-Hillman conditions. The resulting hydrazinonitroalkenes take part in 1,3-dipolar cycloaddition with azide under mild conditions to give hydrazinotriazoles. A [3 + 2] annulation with phenols and naphthols involving Micha...

A new series of pyrrolo[3',4':3,4]pyrrolo[1,2-a]furoquinolines/phenanthrolines and pyrrolo[1,2-a]phenanthrolines were efficiently built up from an 8-hydroxyquinoline derivative or phenanthroline via 1,3-dipolar cycloaddition reaction involving non-stabilized azomethine ylides, generated in situ from the parent furo[3,2-h]quinoliniums/phenanthroliums, in presence of a copper(II) chloride-phenant...

An efficient, general and practical synthesis of diverse 3,4-dihydropyrazines, 6,7-dihydro-[1,2,3]triazolopyrazines and 7,8-dihydro-[1,2,3]triazolodiazepines through intramolecular 1,3-dipolar cycloaddition from amino acid derived common intermediates with high yields is described. Moreover, one-pot access to optically active 3-aryl substituted 6,7-dihydro-[1,2,3]triazolo[1,5-a]pyrazines in the...