Catalyzed and uncatalyzed procedures for the syntheses of isomeric covalent multi-indolyl hetero non-metallides: an account

• Ranadeep Talukdar

Beilstein J. Org. Chem. 2021, 17, 2102–2122, doi:10.3762/bjoc.17.137

• broad applications in organic electroluminescent devices [44]. Silanes Heteroaryl compounds containing silicon, an earth abundant and non-toxic element, are important in organic electronics or photonics and in the field of drug discovery and nuclear medicine [45][46][47][48][49][50]. The first property

Regioselective N-alkylation of the 1H-indazole scaffold; ring substituent and N-alkylating reagent effects on regioisomeric distribution

• Ryan M. Alam and
• John J. Keating

Beilstein J. Org. Chem. 2021, 17, 1939–1951, doi:10.3762/bjoc.17.127

• an improved and cost-effective approach to N-1 substituted indazole precursors as part of drug discovery and development campaigns. Results and Discussion Working towards the synthesis of a library of novel 1,3-disubstituted indazole derivatives necessitated us to develop a regioselective method that

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

• , introduction of fluorine into selective positions of a bioactive compound can produce remarkable changes in efficacy. Fluorine-scan/fluorine editing of a lead molecule is now a routine step in drug discovery [8]. Organofluorine compounds are very rare in nature [9] and therefore without natural compounds

Sustainable manganese catalysis for late-stage C–H functionalization of bioactive structural motifs

• Jongwoo Son

Beilstein J. Org. Chem. 2021, 17, 1733–1751, doi:10.3762/bjoc.17.122

• strategy, is regarded as a crucial tactic in the area of natural products, drug discovery, and medicinal chemistry [7][8][9][10][11][12] as it confers an invaluable synthetic opportunity for the facile diversification of biologically active complex molecules at the late stage. In recent years, much effort

• protein–ligand binding properties as well as biological activities of small molecules, potentially leading to dramatic increases in potency, and thus has been widely explored in drug discovery [54][55][56]. Late-stage C–H methylation has recently been investigated using iron and cobalt catalysts as

• -economical approach to several tryptophan-containing peptides with significant potential for drug discovery and medicinal chemistry. Positional selectivity was observed at the C2 position due to the presence of the pyrimidine directing group. Interestingly, alkynylative conjugation of tryptophan to a steroid

Methodologies for the synthesis of quaternary carbon centers via hydroalkylation of unactivated olefins: twenty years of advances

• Thiago S. Silva and
• Fernando Coelho

Beilstein J. Org. Chem. 2021, 17, 1565–1590, doi:10.3762/bjoc.17.112

• molecular complexity of drugs in drug discovery programs, aiming at molecules with better selectivity for biological targets [6][15][16]. One ideal way to achieve more complex molecular architectures is by hydroalkylation of olefins, a reaction that forms new C(sp3)–C(sp3) and C(sp3)–H bonds at the expense

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• this case from 1-Boc-azetidine-3-carboxylate 46, instead of ethyl cyclobutanecarboxylate 43 [82]. This structural motif was found to have similar physicochemical properties as 2-substituted piperazines, which are key intermediates in drug discovery. The applied protocol was found to be practical for

Synthetic accesses to biguanide compounds

• Oleksandr Grytsai,
• Cyril Ronco and
• Rachid Benhida

Beilstein J. Org. Chem. 2021, 17, 1001–1040, doi:10.3762/bjoc.17.82

• . Furthermore, it usually displays a high polarity and consequently good aqueous solubility. These features render biguanides an attractive chemical function in medicinal chemistry, where it tends to establish as a valuable pharmacophore for drug discovery. Currently, seven biguanide drugs are commercially

Synthesis of 10-O-aryl-substituted berberine derivatives by Chan–Evans–Lam coupling and investigation of their DNA-binding properties

• Peter Jonas Wickhorst,
• Mathilda Blachnik,
• Denisa Lagumdzija and
• Heiko Ihmels

Beilstein J. Org. Chem. 2021, 17, 991–1000, doi:10.3762/bjoc.17.81

• complementary class of arylated berberine derivatives was discovered, which may constitute a promising starting point for the development of lead structures in drug discovery. Experimental Equipment Absorption spectra: Varian Cary 100 Bio spectrophotometer in quartz cells (10 mm × 4 mm) with baseline correction

Prins cyclization-mediated stereoselective synthesis of tetrahydropyrans and dihydropyrans: an inspection of twenty years

• Asha Budakoti,
• Pradip Kumar Mondal,
• Prachi Verma and
• Jagadish Khamrai

Beilstein J. Org. Chem. 2021, 17, 932–963, doi:10.3762/bjoc.17.77

• Asha Budakoti Pradip Kumar Mondal Prachi Verma Jagadish Khamrai Division of Molecular Synthesis & Drug Discovery, Centre of Biomedical Research (CBMR), SGPGIMS Campus Raebareli Road, Lucknow, 226014 Uttar Pradesh, India 10.3762/bjoc.17.77 Abstract Functionalized tetrahydropyran (THP) rings are

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• enhanced yield and efficiency with microwave assistance. The highlights of MWA-MCRs are high yields, reduced reaction time, selectivity, atom economy and simpler purification techniques, such an approach can accelerate the drug discovery process. The present review focuses on the recent advances in MWA

• majority of the atoms of the starting materials. The ability of forming multiple bonds in one-pot via a multicomponent reaction provides a novel and sustainable method in drug discovery [4]. In the recent years, these reactions have emerged as a promising strategy following green chemistry principles such

• atorvastatin, a potent HMG-CoA reductase inhibitor. Dömling and co-workers efficiently demonstrated an Ugi-based MCR approach towards the synthesis of atorvastatin in four steps ruling out the lengthy seven step protocol, and paving a rapid entry to the drug discovery market [12]. Alternatively, microwave

Synthesis of trifluoromethyl ketones by nucleophilic trifluoromethylation of esters under a fluoroform/KHMDS/triglyme system

• Yamato Fujihira,
• Yumeng Liang,
• Makoto Ono,
• Kazuki Hirano,
• Takumi Kagawa and
• Norio Shibata

Beilstein J. Org. Chem. 2021, 17, 431–438, doi:10.3762/bjoc.17.39

• disappeared completely after purification by silica gel column chromatography [73]. Given the relevance of this trifluoromethylation reaction system for drug discovery, we conducted a robustness screening experiment to gain further information on its tolerance to various pharmacophores (Table 2). A range of

Hydrazides in the reaction with hydroxypyrrolines: less nucleophilicity – more diversity

• Dmitrii A. Shabalin,
• Evgeniya E. Ivanova,
• Igor A. Ushakov,
• Elena Yu. Schmidt and
• Boris A. Trofimov

Beilstein J. Org. Chem. 2021, 17, 319–324, doi:10.3762/bjoc.17.29

• emphasis on the nature of hydrazine derivatives still remains obscure. Meeting this challenge becomes particularly important in view of the significance of the less nucleophilic hydrazides as N–N-bond containing starting materials in drug discovery [13][14][15][16]. Herein, we report how a lower

• focuses on the study of partially saturated molecules because sp3 carbon centers make the molecules potentially chiral and 3D structured, which improves the odds for drug discovery [17]. Results and Discussion On the basis of our previous works [11][12] the reaction of 3,3-dimethyl-5-hydroxy-2-phenyl-Δ1

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

A sustainable strategy for the straightforward preparation of 2H-azirines and highly functionalized NH-aziridines from vinyl azides using a single solvent flow-batch approach

• Michael Andresini,
• Leonardo Degannaro and
• Renzo Luisi

Beilstein J. Org. Chem. 2021, 17, 203–209, doi:10.3762/bjoc.17.20

• ]. Within the synthetic chemistry context, the preparation of aziridines still generates interest, mostly because of their importance as source for drug prototypes and drug discovery leads [12]. Interestingly, important advances have been recently addressed in the synthesis of NH-aziridines directly from

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

• Yukiko Karuo,
• Ayaka Kametani,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2021, 17, 89–96, doi:10.3762/bjoc.17.9

• ], which suggests the importance of the difluoromethylene unit in drug discovery (Figure 1). There have been many reports for the construction of the difluoromethylene unit, such as the deoxygenating conversion of a carbonyl group to the difluoromethylene unit using N,N-diethylaminosulfur trifluoride (DAST

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247

• detection The genetic information carrier nucleic acids are present in nearly all living organisms. Fluorescence monitoring of nucleic acids has become increasingly important in medical diagnosis, drug discovery, environmental monitoring, food safety etc. [40][41]. Schmuck et al. reported several

Vicinal difluorination as a C=C surrogate: an analog of piperine with enhanced solubility, photostability, and acetylcholinesterase inhibitory activity

• Yuvixza Lizarme-Salas,
• Alexandra Daryl Ariawan,
• Ranjala Ratnayake,
• Hendrik Luesch,
• Angela Finch and
• Luke Hunter

Beilstein J. Org. Chem. 2020, 16, 2663–2670, doi:10.3762/bjoc.16.216

• Yuvixza Lizarme-Salas Alexandra Daryl Ariawan Ranjala Ratnayake Hendrik Luesch Angela Finch Luke Hunter School of Chemistry, University of New South Wales (UNSW), Sydney NSW 2052, Australia Department of Medicinal Chemistry and Center for Natural Products, Drug Discovery and Development (CNPD3

Catalytic trifluoromethylation of iodoarenes by use of 2-trifluoromethylated benzimidazoline as trifluoromethylating reagent

• Tatsuhiro Uchikura,
• Nanami Kamiyama,
• Taisuke Ishikawa and
• Takahiko Akiyama

Beilstein J. Org. Chem. 2020, 16, 2442–2447, doi:10.3762/bjoc.16.198

• ; catalysis; copper; fluorine chemistry; trifluoromethylation; Introduction The introduction of a trifluoromethyl group is one of the most attractive reactions in drug discovery [1][2]. In the past decade, trifluoromethylation reactions of aryl halides in the presence of transition-metal complexes were

Synthesis of 1,4-benzothiazinones from acylpyruvic acids or furan-2,3-diones and o-aminothiophenol

• Ekaterina E. Stepanova,
• Maksim V. Dmitriev and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2020, 16, 2322–2331, doi:10.3762/bjoc.16.193

• Higher Education of the Russian Federation (FSNF-2020-0008). Antimicrobial screening was performed by CO-ADD (The Community for Antimicrobial Drug Discovery), funded by the Wellcome Trust (UK) and The University of Queensland (Australia).

Chan–Evans–Lam N1-(het)arylation and N1-alkеnylation of 4-fluoroalkylpyrimidin-2(1H)-ones

• Viktor M. Tkachuk,
• Oleh O. Lukianov,
• Mykhailo V. Vovk,
• Isabelle Gillaizeau and
• Volodymyr A. Sukach

Beilstein J. Org. Chem. 2020, 16, 2304–2313, doi:10.3762/bjoc.16.191

• chemistry, given the great importance of fluorinated groups in drug discovery [26][27][28][29]. On the strength of these results, herein we aim at extending the range of available compounds I by the introduction of (het)aryl and alkenyl substituents at the N1 position of the pyrimidine ring. Such

Polarity effects in 4-fluoro- and 4-(trifluoromethyl)prolines

• Vladimir Kubyshkin

Beilstein J. Org. Chem. 2020, 16, 1837–1852, doi:10.3762/bjoc.16.151

• ], organocatalysis [102], drug discovery [103] and more. A) Three types of the backbone amino acid structures that are included in protein translation: glycine, alanine, and the set of its structural derivatives, proline. B) The portfolio of the fluorinated amino acids developed to date. The set of amino acids

Pauson–Khand reaction of fluorinated compounds

• Jorge Escorihuela,
• Daniel M. Sedgwick,
• Alberto Llobat,
• Mercedes Medio-Simón,
• Pablo Barrio and
• Santos Fustero

Beilstein J. Org. Chem. 2020, 16, 1662–1682, doi:10.3762/bjoc.16.138

• the PKR of enynes containing a fluoride moiety. Keywords: alkene; alkyne; enyne; fluorine; Pauson–Khand; Introduction The prevalence of fluorine-containing molecules in drug-discovery programs is nowadays unquestionable [1][2][3]. The presence of fluorine atoms or fluorine-containing units at

Fluorohydration of alkynes via I(I)/I(III) catalysis

• Jessica Neufeld,
• Constantin G. Daniliuc and
• Ryan Gilmour

Beilstein J. Org. Chem. 2020, 16, 1627–1635, doi:10.3762/bjoc.16.135

• fluorine as a powerful physicochemical modulator in small-molecule drug discovery is a compelling argument for the importance of sustained innovation to facilitate this form of structural editing [1][2][3][4]. Routinely employed as a bioisostere of hydrogen or hydroxy [5][6], substitution may enable

• non-covalent interactions [8][9][10]. These collective attributes render fluorination a valuable strategy in drug discovery [11] and agrochemical development [12]. In the conception of enabling fluorination technologies, the α-fluorocarbonyl motif has emerged as a prominent target scaffold [13

One-pot synthesis of 1,3,5-triazine-2,4-dithione derivatives via three-component reactions

• Gui-Feng Kang and
• Gang Zhang

Beilstein J. Org. Chem. 2020, 16, 1447–1455, doi:10.3762/bjoc.16.120

• compounds, triazines and substituted triazines are of particular utility in drug discovery because of their broad potential biological activities [8][9]. Besides, triazinethiones also played important roles in the construction of an array of pharmacologically important compounds (Figure 1), comprising

• benign methodologies for the generation of structurally diverse triazinethione derivatives is still challenging in organic synthetic chemistry and medicinal chemistry. Multicomponent reactions (MCRs) gained much interest among synthetic organic chemists as well as in combinatorial chemistry and drug

• discovery as versatile tools for the construction of different biologically active compounds by combining three or more starting materials into a single product in one convergent chemical step [19][20][21][22][23]. Among multicomponent reactions, aldehydes have emerged as one of the most useful class of