A5041263327- Asymmetric Synthesis and Catalysis
- Asymmetric Hydrogenation and Catalysis
- Axial and Atropisomeric Chirality Synthesis
- Synthetic Organic Chemistry Methods
- Chemical Synthesis and Analysis
- Oxidative Organic Chemistry Reactions
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Chemical synthesis and alkaloids
- Microbial Natural Products and Biosynthesis
- Crystallography and molecular interactions
- Inorganic and Organometallic Chemistry
- Fluorine in Organic Chemistry
- Carbohydrate Chemistry and Synthesis
- Advanced Synthetic Organic Chemistry
- Alkaloids: synthesis and pharmacology
- Synthesis and Reactivity of Heterocycles
- Antibiotic Resistance in Bacteria
- Antimicrobial Resistance in Staphylococcus
- Marine Sponges and Natural Products
- Mycobacterium research and diagnosis
- Magnolia and Illicium research
- Sulfur-Based Synthesis Techniques
- Cyclopropane Reaction Mechanisms
- Chemical Synthesis and Reactions
Universidade de São Paulo
2023-2024
Universidade Estadual de Campinas (UNICAMP)
2022
Rede de Química e Tecnologia
2021
Aarhus University
2014-2017
Abstract A novel asymmetric organocatalytic 1,6‐addition/1,4‐addition sequence to 2,4‐dienals is described. Based on a 1,6‐Friedel–Crafts/1,4‐oxa‐Michael cascade, the organocatalyst directs reaction of hydroxyarenes with vinylogous iminium‐ion intermediate give only one out four possible regioisomers, thus providing optically active chromans in high yields and 94–99 % ee . Furthermore, several transformations are presented, including formation an macrocyclic lactam. Finally, mechanism for...
ConspectusAsymmetric organocatalysis has witnessed a remarkable development since its "re-birth" in the beginning of millenium. In this rapidly growing field, computational investigations have proven to be an important contribution for elucidation mechanisms and rationalizations stereochemical outcomes many reaction concepts developed. The improved understanding mechanistic details facilitated further advancement field. diarylprolinol-silyl ethers their introduction been one most applied...
Abstract The stereochemical outcome of most aminocatalytic transformations is determined by the steric‐shielding or hydrogen‐directing approach. However, in recent years several reactions have appeared which beyond these two approaches. This Concept article will highlight such and postulate that can be accounted for electrostatic interactions between catalyst‐bound substrate reagent transition state.
A novel enantioselective organocatalytic strategy is presented for the synthesis of tetrahydrofurobenzofuran and methanobenzodioxepine natural product core structures. The based on a pair divergent reaction pathways in which hydroxyarenes react with γ-keto-α,β-unsaturated aldehydes, catalyzed by chiral secondary amine. One pathway, leads to 5,5-fused acetals two stereocenters-the scaffolds-proceeds moderate yields up 96 % ee. other pathway provides 5,6-bridged scaffolds three stereocenters...
Abstract A novel asymmetric organocatalytic 1,6‐addition/1,4‐addition sequence to 2,4‐dienals is described. Based on a 1,6‐Friedel–Crafts/1,4‐oxa‐Michael cascade, the organocatalyst directs reaction of hydroxyarenes with vinylogous iminium‐ion intermediate give only one out four possible regioisomers, thus providing optically active chromans in high yields and 94–99 % ee . Furthermore, several transformations are presented, including formation an macrocyclic lactam. Finally, mechanism for...
Attractive carbocyclic structures are accessed via a highly regio- and enantioselective aminocatalytic γ-addition of cyclic enals to vinyl phosphonates followed by one-pot intramolecular Horner–Wadsworth–Emmons reaction. It is also demonstrated that nitro olefins can act as electrophiles in similar reaction concept, providing carbocycles equally high stereoselectivity.
An enantioselective organocatalytic strategy, combining Brønsted base and N-heterocyclic carbene catalysis in a unique manner, is demonstrated for concise construction of the privileged cyclopenta[<italic>b</italic>]benzofuran scaffold, present many bioactive compounds having both academic commercial interests.
Abstract The structure proposed for the putative Stemona alkaloid named as parvistemoamide ( 4 a or b ) has been questioned after revising literature data and an attempted preparation of , which led to 5 : 1 mixture (±)‐stemoamide ). Studies on intramolecular Friedel‐Crafts alkylation furan 12 containing Z double bond tethered precursor N ‐acyliminium ion are reported. As shown bromo substituted 31 cyclization occurred when 4‐carbon saturated tether was present, allowing formal syntheses...
MOLECULAR SYMMETRY AND DESYMMETRIZATION REACTIONS IN ORGANIC SYNTHESIS. Molecular Symmetry has found several applications in Organic Chemistry. The aim of this article is to showcase its relevance as a tool for synthetic planning. Natural Products and compounds with pharmaceutical were selected highlight desymmetrization reactions that make use organocatalysis, biocatalysis or by transition metals. recognition structural patterns retrosynthetic analysis discussed exhibit explicit hidden...
Abstract Review: 32 refs.
Abstract Vinyl phosphonates (II) and (VIII) as well nitro olefins (XI) (XIII) react with annulated cyclic enals (I), (IV), (VI) (X) to carbocyclic derivatives (III), (V), (VII), (IX), (XII), (XIV) in a highly regio‐ enantioselective manner using proline‐based chiral catalysts.
Abstract A wide range of optically active chromans are highly regio‐ and stereoselectively obtained utilizing a novel asymmetric 1,6‐Friedel—Crafts/1,4‐oxa‐Michael cascade reaction hydroxyarenes with 2,4‐dienals.
Abstract Review: [33 refs.
Abstract Flavonoids and cannabinoids comprise two large families of natural products that contain a chromane moiety in their structure. Their therapeutic potential has been extensively investigated as treatments to several diseases, ranging from cancer infectious neurodegenerative diseases. Despite relative structural simplicity, recent years creative synthetic methodologies were designed overcome limitations the previous strategies applied these compounds. The aim this review is provide...
Key words seneciobipyrrolidine - phenotypic screening glucose homeostasis
Key words phase-transfer catalysis - double alkylation spirocyclic oxindoles
Key words pseudo-natural products - LC3 lipidation inducers macrocyclic dimers 1,3-dipolar cycloaddition
Key words antibiotics - stereochemical assignment stereoselective mannosylation