The Asymmetric Total Synthesis of (+)- and (−)-Spirotryprostatin B

Regio- and diastereoselective construction of 1′,2′-(dihydrospiro[indoline-3,3′-pyrrol]-2′-yl)acrylates through phosphine-catalyzed [4 + 1] annulation of Morita–Baylis–Hillman carbonates with oxindole-derived α,β-unsaturated imines

Phosphine-catalyzed [4 + 1] annulation of Morita–Baylis–Hillman carbonates with oxindole-derived imines has been developed.

N-heterocyclic carbene-catalyzed [4 + 2] cyclization of 2-bromo-2-enal with 3-alkylenyloxindoles: efficient assembly of spirocarbocyclic oxindole

A NHC-catalyzed [4 + 2] cyclization of 2-bromo-2-enal bearing γ-H with 3-alkylenyloxindoles under mild reaction conditions gives spirocarbocyclic oxindoles containing one quaternary carbon with high diastereoselectivies.

One-pot four-component reaction for convenient synthesis of functionalized 1-benzamidospiro[indoline-3,4'-pyridines]

The one-pot four-component reaction of benzohydrazide (2-picolinohydrazide), acetylenedicarboxylate, isatins and malononitrile (ethyl cyanoacetate) with triethylamine as base catalyst afforded functionalized 1-benzamidospiro[indoline-3,4'-pyridines] in good yields. (1)H NMR spectra indicated that an equilibrium of cis/trans-conformations exist in the obtained products.

Diversity-oriented synthesis as a tool for chemical genetics

Chemical genetics is an approach for identifying small molecules with the ability to induce a biological phenotype or to interact with a particular gene product, and it is an emerging tool for lead generation in drug discovery. Accordingly, there is a need for efficient and versatile synthetic processes capable of generating complex and diverse molecular libraries, and Diversity-Oriented Synthesis (DOS) of small molecules is the concept of choice to give access to new chemotypes with high chemical diversity. In this review, the combination of chemical genetics and diversity-oriented synthesis to identify new chemotypes as hit compounds in chemical biology and drug discovery is reported, giving an overview of basic concepts and selected case studies.

Domino reactions of vinyl malononitriles with 3-phenacylideneoxindoles for efficient synthesis of functionalized spirocyclic oxindoles

The reactions of vinyl malononitriles with 3-phenacylideneoxindoles in ethanol in the presence of DBU as base resulted in the functionalized spirocyclic oxindoles through the domino Michael addition and intramolecular nucleophilic addition to cyano group. On the other hand, the similar reaction in the presence of piperidine as base afforded the simple Michael addition products in good yields. The stereochemistry of the spirooxindoles was established with (1)H NMR data and single crystal structures.

Catalytic enantioselective 1,3-dipolar cycloadditions of azomethine ylides for biology-oriented synthesis

Cycloaddition reactions are among the most powerful methods for the synthesis of complex compounds. In particular, the development and application of the 1,3-dipolar cycloaddition, an important member of this reaction class, has grown immensely due to its powerful ability to efficiently build various five-membered heterocycles. Azomethine ylides are commonly used as dipoles for the synthesis of the pyrrolidine scaffold, which is an important motif in natural products, pharmaceuticals, and biological probes. The reaction between azomethine ylides and cyclic dipolarophiles allows access to polycyclic products with considerable complexity. The extensive application of the 1,3-dipolar cycloaddition is based on the fact that the desired products can be obtained with high yield in a regio- and stereocontrolled manner. The most attractive feature of the 1,3-dipolar cycloaddition of azomethine ylides is the possibility to generate pyrrolidines with multiple stereocenters in a single step. The development of enantioselective cycloadditions became a subject of intensive and impressive studies in recent years. Among many modes of stereoinduction, the application of chiral metal-ligand complexes has emerged as the most viable option for control of enantioselectivity. In chemical biology research based on the principle of biology-oriented synthesis (BIOS), compound collections are prepared inspired by natural product scaffolds. In BIOS, biological relevance is employed as the key criterion to generate hypotheses for the design and synthesis of focused compound libraries. In particular, the underlying scaffolds of natural product classes provide inspiration for BIOS because they define the areas of chemical space explored by nature, and therefore, they can be regarded as "privileged". The scaffolds of natural products are frequently complex and rich in stereocenters, which necessitates the development of efficient enantioselective methodologies. This Account highlights examples, mostly from our work, of the application of 1,3-dipolar cycloaddition reactions of azomethine ylides for the catalytic enantioselective synthesis of complex products. We successfully applied the 1,3-dipolar cycloaddition in the synthesis of spiro-compounds such as spirooxindoles, for kinetic resolution of racemic compounds in the synthesis of an iridoid inspired compound collection and in the synthesis of a nitrogen-bridged bicyclic tropane scaffold by application of 1,3-fused azomethine ylides. Furthermore, we performed the synthesis of complex molecules with eight stereocenters using tandem cycloadditions. In a programmable sequential double cycloaddition, we demonstrated the synthesis of both enantiomers of complex products by simple changes in the order of addition of chemicals. Complex products were obtained using enantioselective higher order [6 + 3] cycloaddition of azomethine ylides with fulvenes followed by Diels-Alder reaction. The bioactivity of these compound collections is also discussed.

Asymmetric organocatalysis at the service of medicinal chemistry

The application of the most representative and up-to-date examples of homogeneous asymmetric organocatalysis to the synthesis of molecules of interest in medicinal chemistry is reported. The use of different types of organocatalysts operative via noncovalent and covalent interactions is critically reviewed and the possibility of running some of these reactions on large or industrial scale is described. A comparison between the organo- and metal-catalysed methodologies is offered in several cases, thus highlighting the merits and drawbacks of these two complementary approaches to the obtainment of very popular on market drugs or of related key scaffolds.

The regioselective synthesis of spirooxindolo pyrrolidines and pyrrolizidines via three-component reactions of acrylamides and aroylacrylic acids with isatins and α-amino acids

The regioselective three-component condensation of azomethine ylides derived from isatins and α-amino acids with acrylamides or aroylacrylic acids as dipolarophiles has been realized through a one-pot 1,3-dipolar cycloaddition protocol. Decarboxylation of 2'-aroyl-2-oxo-1,1',2,2',5',6',7',7a'-octahydrospiro[indole-3,3'-pyrrolizine]-1'-carboxylic acids is accompanied by cyclative rearrangement with formation of dihydropyrrolizinyl indolones.

Manganese ferrite nanoparticle catalyzed tandem and green synthesis of spirooxindoles

PEG-400 as a nontoxic, green and reusable solvent was used for the synthesis of novel spiro-furo-pyridine-indoline-carbonitriles in the presence of a magnetically recoverable nanocatalyst.

Rhodium-catalyzed three-component reaction of 3-diazooxindoles with indoles and isatin-derived ketimines: a facile and versatile approach to functionalized 3,3′,3′′-trisindoles

A variety of functionalized 3,3′,3′′-trisindoles could be produced in high yields with moderate to excellent diastereoselectivities via Rh₂(OAc)₄-catalyzed three-component reaction of 3-diazooxindoles with indoles and isatin-derived N-Boc ketimines.

Four-component reaction of N-alkylimidazoles(N-alkylbenzimidazoles), dialkyl but-2-ynedioate, N-alkylisatins and malononitrile

Convenient synthesis of complex spirooxindolesviafour-component reactions ofN-alkylimidazoles(N-alkylbenzimidazoles), dialkyl but-2-ynedioate,N-alkylisatins and malononitrile.

Synthesis of spiro[indoline-3,1'-quinolizines] and spiro[indoline-3, 4'-pyrido[1,2-a]quinolines] via three-component reactions of azaarenes, acetylenedicarboxylate, and 3-methyleneoxindoles

Abstract

The three-component reactions of substituted pyridines, dimethyl acetylenedicarboxylates, and 3-phenacylideneoxindoles afforded spiro[indoline-3,1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^\prime $$\end{document}′-quinolizines] in high yields and with high diastereoselectivity. The Diels–Alder reactions of spiro[indoline-3,1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^\prime $$\end{document}′-quinolizines] with maleic anhydride and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N$$\end{document}N-phenyl maleimides successfully resulted in polyfunctionalized isoquinolinuclidine derivatives. The similar three-component reactions with quinoline resulted in the novel spiro[indoline-3,4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^\prime $$\end{document}′-pyrido[1,2-a]quinolines] in moderate to good yields.

Graphical Abstract

Electronic supplementary material

The online version of this article (doi:10.1007/s11030-013-9459-5) contains supplementary material, which is available to authorized users.