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The review summarizes the methods of synthesis of pyrrolizidine (hexahydro-1H-pyrrolizine) derivatives published in the literature over the past five years. The methods can be conditionally divided into two major groups: synthesis from pyrrolidine derivatives and cyclization of acyclic precursors. [ABSTRACT FROM AUTHOR]

We provide a generalized overview of stereoselective synthetic strategies used for the preparation of tetrahydropyrimidin-2(1H)-one derivatives, illustrated by the most relevant examples published between years 2012 and 2022. The known methods can be divided into two main groups: intramolecular and intermolecular cyclization of unsaturated acyclic amides/ureas, as well as syntheses on the basis of cyclic precursors. [ABSTRACT FROM AUTHOR]

Pyrrolidine-based phosphonates, analogues of the natural amino acid proline, possess a diverse set of biological activity. The goal of this short review is to summarize the major developments in the synthesis of phosphaproline derivatives reported since 2004 with special emphasis on the mechanisms and limitations of the methods presented. 1 Introduction 2 Phosphorylation of Pyrrolidine Derivatives 2.1 Syntheses via Pudovik Reaction 2.2 Syntheses via Arbuzov Reaction 2.3 Decarboxylative Phosphorylation of Proline 2.4 Direct C–H Bond Phosphorylation 2.5 Other Reactions 2.6 Overview of Phosphorylation Methods 3 Synthesis of 2-Phosphorylpyrrolidines from Acyclic Precursors 3.1 Cyclization of 4-Substituted Butylamine Derivatives 3.2 [3+2]-Dipolar Cycloaddition of α-Iminophosphonates 3.3 Cyclization of Aminoalkynes and 4-Aminocarbonyl Compounds 4 Conclusions [ABSTRACT FROM AUTHOR]

Herein, we report the successful application of a novel approach to 2-substituted pyrrolidines based on intramolecular cyclization/intermolecular Mannich-type cascade reaction of N-(4,4-diethoxybutyl)sulfonamides to the synthesis of pyrrolidines possessing heterocyclic and polyaromatic moieties. The proposed approach benefits from mild reaction conditions, moderate to high yields of target compounds and provides a convenient route to the previously unknown 1-sulfonyl-2-arylpyrrolidines. [ABSTRACT FROM AUTHOR]

The rare example of pyrrolidine C-N bond cleavage in 1-sulfonylpyrrolidines in acidic media in the presence of phenols is reported. The reaction proceeds under mild conditions and provides a convenient route to otherwise hardly accessible and previously unknown dibenzoxanthenes, diarylbutanes, and resorcinarenes having a sulfonylamide moiety. [ABSTRACT FROM AUTHOR]

Herein we report our studies on the acid-catalyzed cyclisation of N-(4,4-diethoxybutyl)sulfonamides at the presence of polyatomic phenols as an efficient one-pot approach to the synthesis of 1-sulfonyl-2-arylpyrrolidines from the acyclic precursors. [ABSTRACT FROM PUBLISHER]

This article provides an overview of the most typical strategies and methods applicable for the synthesis of hetaryl-substituted pyrrolidine derivatives, published between 2016 and 2018. The described methods are divided into two main groups: the introduction of heterocyclic substituent in pyrrolidine or its derivatives and the assembly of pyrrolidine ring containing hetaryl substituents from appropriately substituted acyclic precursors. [ABSTRACT FROM AUTHOR]

In this article, we report a regioselective method for the synthesis of new water-soluble 1,3,4-trisubstituted tetrahydropyrimidin-2(1 H)-one derivatives containing sodium methanesulfonate fragment in the first position of the heterocycle. The method is based on the reaction of (1-(3,3-diethoxypropyl)ureido)methanesulfonate with aromatic and heterocyclic nucleophiles. The proposed method is distinguished by the possibility of obtaining a wide range of water-soluble substituted tetrahydropyrimidinone derivatives, the absence of the need to use expensive metal complex catalysts, high product yield, and ease of purification. [Display omitted] [ABSTRACT FROM AUTHOR]

1-(4,4-Diethoxybutyl)-3-alkylureas undergo intramolecular cyclization in the presence of trifluoroacetic acid and various phenols, leading to the new N-alkyl-2-arylpyrrolidine-1-carboxamides with moderate to excellent yields. It was found that these compounds undergo spontaneous solid-phase epimerization at room temperature. Advantages of the proposed approach are mild reaction conditions and no need for expensive reagents or catalysts. [ABSTRACT FROM AUTHOR]

A series of novel 4-(het)arylimidazoldin-2-ones were obtained by the acid-catalyzed reaction of (2,2-diethoxyethyl)ureas with aromatic and heterocyclic C-nucleophiles. The proposed approach to substituted imidazolidinones benefits from excellent regioselectivity, readily available starting materials and a simple procedure. The regioselectivity of the reaction was rationalized by quantum chemistry calculations and control experiments. The anti-cancer activity of the obtained compounds was tested in vitro. [ABSTRACT FROM AUTHOR]