The 3,3'-pyrrolidinyl-spirooxindole unit is a privileged heterocyclic motif that forms the core of a large family of alkaloid natural products with strong bioactivity profiles and interesting structural properties. Significant recent advances in the synthesis of this fused heterocyclic system have led to intense interest in the development of related compounds as potential medicinal agents or biological probes.

Pyrrolidinyl-spirooxindole natural products as inspirations for the development of potential therapeutic agents.

Isatins As Privileged Molecules in Design and Synthesis of Spiro-Fused Cyclic Frameworks

Construction of Spiro[pyrrolidine‐3,3′‐oxindoles] − Recent Applications to the Synthesis of Oxindole Alkaloids

The construction of heterocyclic compounds from activated cyclopropane derivatives offers an alternative strategy for the preparation of molecules that may be of interest from a structural or biological standpoint. Several newly developed methods provide access to densely functionalized heterocycles in a manner that can be considered useful for both diversity- and target-oriented synthetic approaches. This tutorial review focuses on the latter, describing recent developments and applications of cyclopropane ring-expansion reactions in natural product synthesis.

Heterocycles from cyclopropanes: applications in natural product synthesis

The one-pot synthesis of a target molecule in the same reaction vessel is widely considered to be an efficient approach in synthetic organic chemistry. In this review, the characteristics and limitations of various one-pot syntheses of biologically active molecules are explained, primarily involving organocatalytic methods as key tactics. Besides catalysis, the pot-economy concepts presented herein are also applicable to organometallic and organic reaction methods in general.

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Pot economy and one-pot synthesis

Horsfiline, an oxindole alkaloid from Horsfieldia superba

Cinnamrutinoses A and B, glycosides of Populus tremula

Monterine 1 as well as granjine 3, 1R,1‘S configured biphenylic bisbenzylisoquinoline alkaloids, generate two highly populated conformers. The interconversion of two forms was detected by saturation tranfer in 1H NMR NOEs experiments. Tridimensional structure of the conformers was determined on the basis of 1H NMR analysis of anisotropic shielding protons, by NOEs measurements and vicinal proton coupling constants of CH1−CH2α and CH1‘−CH2α‘. The structures established from NMR data were further refined to observe the mobility of 3D conformations by molecular dynamics simulation in vacuo. The highly populated conformers, monterine 1a and 1b, as well as granjine 3a and 3b, are interconvertible by rotation about the C1‘−Cα‘, Cα‘−C9‘, and C11‘−C11 bonds and inversion of the benzyl D ring by reference to CH2α‘. The slow exchange system was investigated by dynamic NMR spectroscopy:  ΔG⧧c 77.9 KJ/mol and kc 200 s-1 for monterine 1; ΔG⧧c 77.7 KJ/mol and kc 211 s-1 for granjine 3. Natural and synthetic biphenylic ...

Two Highly Populated Conformations at Room Temperature of Monterine and Granjine, Antitumor Bisbenzylisoquinoline Alkaloids: Origin and Tridimensional Structures.

Per Jossang

Papers

Horsfiline, an oxindole alkaloid from Horsfieldia superba

Cinnamrutinoses A and B, glycosides of Populus tremula

Two Highly Populated Conformations at Room Temperature of Monterine and Granjine, Antitumor Bisbenzylisoquinoline Alkaloids: Origin and Tridimensional Structures.