Synthesis of substituted triazole–pyrazole hybrids using triazenylpyrazole precursors

• Simone Gräßle,
• Laura Holzhauer,
• Nicolai Wippert,
• Olaf Fuhr,
• Martin Nieger,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2024, 20, 1396–1404, doi:10.3762/bjoc.20.121

• immobilized building blocks. Biologically active pyrazole–triazole hybrids 1–4: inhibitory effect on cholera bacteria [13], antimicrobial properties [14], P2X7 antagonists (depression) [15] and ERK3 inhibition [12]. Synthesized triazole–pyrazole hybrids 21aa–vg. Literature-reported synthetic routes to

Synthetic applications of the Cannizzaro reaction

• Bhaskar Chatterjee,
• Dhananjoy Mondal and
• Smritilekha Bera

Beilstein J. Org. Chem. 2024, 20, 1376–1395, doi:10.3762/bjoc.20.120

• where other methods of oxidation or reduction might be challenging or impractical. The present discussion focuses on some recent synthetic advances and their application in biologically active compounds. Lewis acid-catalyzed intramolecular Cannizzaro reaction Wang et al. [73] depicted a highly

Mild and efficient synthesis and base-promoted rearrangement of novel isoxazolo[4,5-b]pyridines

• Vladislav V. Nikol’skiy,
• Mikhail E. Minyaev,
• Maxim A. Bastrakov and
• Alexey M. Starosotnikov

Beilstein J. Org. Chem. 2024, 20, 1069–1075, doi:10.3762/bjoc.20.94

• activity, such as antibacterial [8], anticancer [9] or antiproliferative [10]. In addition, isoxazolo[4,5-b]pyridines were found to inhibit cytochrome P450 CYP17 responsible for the biosynthesis of androgens and estrogen precursors [11]. Some biologically active isoxazolo[4,5-b]pyridines are shown on

• -oriented heterocyclic systems. Some examples of biologically active isoxazolo[4,5-b]pyridines with antibacterial [8], anticancer [12] and cytotoxic [10][13] acitivities. Biologically active analogs of compounds 13. X-ray crystal structures of compounds 12c (top left; the second crystallographically unique

Novel analogues of a nonnucleoside SARS-CoV-2 RdRp inhibitor as potential antivirotics

• Luca Julianna Tóth,
• Kateřina Krejčová,
• Milan Dejmek,
• Eva Žilecká,
• Blanka Klepetářová,
• Lenka Poštová Slavětínská,
• Evžen Bouřa and
• Radim Nencka

Beilstein J. Org. Chem. 2024, 20, 1029–1036, doi:10.3762/bjoc.20.91

• still scarce. Recently, many studies have been focusing on drug repurposing or screening libraries of already approved biologically active compounds [16][17]. This approach might represent a very promising strategy in the case of targeting the coronaviral RdRp due to the highly conserved structure of

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

• Naoki Miyamoto,
• Daichi Koseki,
• Kohei Sumida,
• Elghareeb E. Elboray,
• Naoko Takenaga,
• Ravi Kumar and
• Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

• series of functional groups. As a result, this process can be applied for the unique hybridization of biologically active and fluorescently-labeled carboxylic acids with diaryliodonium(III) salts. We anticipate that this study will encourage the incorporation of diaryliodonium(III) carboxylates in

Carbonylative synthesis and functionalization of indoles

• Alex De Salvo,
• Raffaella Mancuso and
• Xiao-Feng Wu

Beilstein J. Org. Chem. 2024, 20, 973–1000, doi:10.3762/bjoc.20.87

• ][4]. The indole core is particularly noteworthy for its role in various biologically active compounds and drugs, such as antihypertensives, anti-inflammatories, antimycotics, antimigrants, anticancer drugs, and many others [5][6][7]. The first synthesis of indole has been introduced by Fischer in

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• addition to the above physicochemical data, Mykhailiuk and co-workers assessed the antifungal activity of the suggested fluxapyroxad and boscalid bioisosteres (±)-75 and (±)-76 (Figure 12) [45]. The collected data shows that the isosteres, while still biologically active, are overall less active than the

Genome mining of labdane-related diterpenoids: Discovery of the two-enzyme pathway leading to (−)-sandaracopimaradiene in the fungus Arthrinium sacchari

• Fumito Sato,
• Terutaka Sonohara,
• Shunta Fujiki,
• Akihiro Sugawara,
• Yohei Morishita,
• Taro Ozaki and
• Teigo Asai

Beilstein J. Org. Chem. 2024, 20, 714–720, doi:10.3762/bjoc.20.65

• understand the evolutionary traits of TCs. Among terpenoids, labdane-related diterpenoids (LRDs) are an important class which includes biologically active molecules such as plant hormone gibberellins (Figure 1A). In their biosynthesis, class II TCs often synthesize copalyl diphosphate (CPP) or its

Entry to new spiroheterocycles via tandem Rh(II)-catalyzed O–H insertion/base-promoted cyclization involving diazoarylidene succinimides

• Alexander Yanovich,
• Anastasia Vepreva,
• Ksenia Malkova,
• Grigory Kantin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2024, 20, 561–569, doi:10.3762/bjoc.20.48

• properties are exhibited by compounds based on a THF and THP core spiro-conjugated with the pyrrolidine ring. These frameworks are present in a number of synthetic biologically active compounds (such as NaV1.7 blocker XEN907 for the treatment of pain [31], σ1 receptor ligand 6 [32], histamine-3 receptor

• )ethanol. In the latter case, the predominant process was found to be the base-promoted migration of the C=C bond of the arylidene fragment into the cycle. Examples of biologically active compounds and natural products based on THF/THP spiro-conjugates with pyrrolidine rings. DAS spirocyclizations reported

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

• Rattiya Janthanom,
• Yuta Kikuchi,
• Hiroki Kanto,
• Tomoyasu Hirose,
• Arisu Tahara,
• Takahiro Ishii,
• Arinthip Thamchaipenet and
• Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

• Actinomycetes are well-known as the main producers of bioactive compounds such as antibiotics, anticancers, and immunosuppressants. Screening of natural products from actinomycetes has been an essential part of several drug discovery programs. Finding such novel biologically active metabolites is immensely

Metal-catalyzed coupling/carbonylative cyclizations for accessing dibenzodiazepinones: an expedient route to clozapine and other drugs

• Amina Moutayakine and
• Anthony J. Burke

Beilstein J. Org. Chem. 2024, 20, 193–204, doi:10.3762/bjoc.20.19

• biologically active natural products such as BU-4664L. We are currently looking at this methodology to access some of these targets, including the agrochemical boscalid. Experimental Synthesis of o-(2-bromophenyl)aminoaniline (3a) Via Buchwald–Hartwig coupling: o-Phenylenediamine (1a, 0.05g, 1 equiv, 0.46 mmol

• ): 221.12 [M + H+]. Biologically active dibenzodiazepinones. Different synthetic routes to DBDAPs (a–c), including our novel approach (d). One-pot synthesis of 5H-dibenzo[b,e][1,4]diazepin-11-ol (5). Scope of the Chan–Lam coupling between o-phenylenediamines and 2-bromophenylboronic acids (please note

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

• Pavel S. Silaichev,
• Tetyana V. Beryozkina,
• Vsevolod V. Melekhin,
• Valeriy O. Filimonov,
• Andrey N. Maslivets,
• Vladimir G. Ilkin,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

• of hybrids of 1,2,3-triazole with other heterocycles and to identify biologically active compounds among the synthesized compounds. It is known that the cycloaddition reaction of azidopyrimidinediones with enamines [13] represents an effective method for the synthesis of pyrimidinyl amidines [14

Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors

• Yordanka Mollova-Sapundzhieva,
• Plamen Angelov,
• Danail Georgiev and
• Pavel Yanev

Beilstein J. Org. Chem. 2023, 19, 1804–1810, doi:10.3762/bjoc.19.132

• sensing; Introduction Among the vast number of biologically active quinoline derivatives [1][2], the subclass of 4-quinolones (also referred to as 4-oxo-1,4-dihydroquinolines, quinolin-4(1H)-ones, or 4-hydroxyquinolines) is of great importance with its rich variety of bioactive compounds. Perhaps the

Decarboxylative 1,3-dipolar cycloaddition of amino acids for the synthesis of heterocyclic compounds

• Xiaofeng Zhang,
• Xiaoming Ma and
• Wei Zhang

Beilstein J. Org. Chem. 2023, 19, 1677–1693, doi:10.3762/bjoc.19.123

• scaffold can be found in many biologically active compounds and natural products such as 1-epiaustraline, hyacinthacine A1, (−)-isoretronecanol, and (−)-supinidine (Figure 2) [68][69]. After the method development work, a pseudo-five-component double cycloaddition reaction of glycine with two equivalents

• pyrrolizidines shown in Scheme 6 and Scheme 7, we then conducted similar reactions in order to synthesize spirooxindole-pyrrolidines. This unique ring skeleton exists in some natural products and biologically active compounds such as (−)-horsfiline, (+)-alstonisine, pteropodine and spirotryprostatin A (Figure 3

Synthesis of 7-azabicyclo[4.3.1]decane ring systems from tricarbonyl(tropone)iron via intramolecular Heck reactions

• Aaron H. Shoemaker,
• Elizabeth A. Foker,
• Elena P. Uttaro,
• Sarah K. Beitel and
• Daniel R. Griffith

Beilstein J. Org. Chem. 2023, 19, 1615–1619, doi:10.3762/bjoc.19.118

• Aaron H. Shoemaker Elizabeth A. Foker Elena P. Uttaro Sarah K. Beitel Daniel R. Griffith Department of Chemistry, Lafayette College, 730 High St., Easton, PA 18042, USA 10.3762/bjoc.19.118 Abstract The 7-azabicyclo[4.3.1]decane ring system, common to a number of biologically active alkaloids, was

• related 2-azabicyclo[4.4.1]undecane system, albeit in lower yield. Keywords: alkaloids; azabicycles; Heck reaction; iron complex; tropone; Introduction Azapolycycles are embedded within numerous biologically active alkaloids [1] and pharmaceuticals [2]. As such, novel approaches to the synthesis of

• these scaffolds, even though they are found within a number of biologically active alkaloids. We recently demonstrated that the readily available, bench-stable tricarbonyl(tropone)iron complex [4] (1, Scheme 1) could serve as a precursor to the previously unreported 2-azatricyclo[4.3.2.04,9]undecane

Secondary metabolites of Diaporthe cameroonensis, isolated from the Cameroonian medicinal plant Trema guineensis

• Bel Youssouf G. Mountessou,
• Élodie Gisèle M. Anoumedem,
• Blondelle M. Kemkuignou,
• Yasmina Marin-Felix,
• Frank Surup,
• Marc Stadler and
• Simeon F. Kouam

Beilstein J. Org. Chem. 2023, 19, 1555–1561, doi:10.3762/bjoc.19.112

• far from being accessed [2][3], they have been considered as an untapped microbial reservoir capable of producing a wide range of structurally unique natural products with potent pharmacological effects [4]. However, the production of biologically active compounds by filamentous fungi, especially

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• interest as indole-based blue emitters in solution and in the solid state. The expansion of this practical concise synthesis of indoles and azaindoles and their exploration as biologically active apoptosis inducers [37] and as functional blue emitters is currently underway. Experimental Consecutive four

Non-noble metal-catalyzed cross-dehydrogenation coupling (CDC) involving ether α-C(sp³)–H to construct C–C bonds

• Hui Yu and
• Feng Xu

Beilstein J. Org. Chem. 2023, 19, 1259–1288, doi:10.3762/bjoc.19.94

• CDC reaction to be a new generation method for the construction of C–C bonds and it has received extensive attention and in-depth research [16][17][18][19][20][21][22][23][24]. The building blocks of ethers are widely found in biomass, chemical feedstocks, biologically active drugs, and natural

Metal catalyst-free N-allylation/alkylation of imidazole and benzimidazole with Morita–Baylis–Hillman (MBH) alcohols and acetates

• Olfa Mhasni,
• Jalloul Bouajila and
• Farhat Rezgui

Beilstein J. Org. Chem. 2023, 19, 1251–1258, doi:10.3762/bjoc.19.93

• Michael acceptor unit. They have found application as valuable synthons and useful precursors for the synthesis of various biologically active molecules [1][2][3]. Recently, MBH adducts, as electrophilic substrates, have been employed to achieve fruitful results in allylic substitution reactions with

Cyanothioacetamides as a synthetic platform for the synthesis of aminopyrazole derivatives

• Valeriy O. Filimonov,
• Alexandra I. Topchiy,
• Vladimir G. Ilkin,
• Tetyana V. Beryozkina and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2023, 19, 1191–1197, doi:10.3762/bjoc.19.87

• biologically active substances containing amide groups [14]. The presence of a pyrazole core and a thioamide group within the hybrid molecules that we are planning to obtain, allows us to expect both an increase in their activity and the emergence of other types of biological activity, and also high synthetic

New one-pot synthesis of 4-arylpyrazolo[3,4-b]pyridin-6-ones based on 5-aminopyrazoles and azlactones

• Vladislav Yu. Shuvalov,
• Ekaterina Yu. Vlasova,
• Tatyana Yu. Zheleznova and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2023, 19, 1155–1160, doi:10.3762/bjoc.19.83

• when irradiated with UV light. Keywords: 5-aminopyrazole; azlactone; elimination; fluorescence; one-pot synthesis; pyrazolo[3,4-b]pyridin-6-one; Introduction The pyrazolo[3,4-b]pyridine scaffold is present in many biologically active compounds [1][2][3][4][5][6][7][8][9][10][11][12]. Among them, 4

• -aminopyrazoles 1, 5, 6 and azlactones 2a–i, followed by heating the resulting intermediate in DMSO in the presence of t-BuOK. Photophysical properties of the obtained compounds were studied. Biologically active 4-arylpyrazolo[3,4-b]pyridin-6-ones. Normalized absorption and fluorescence spectra of solutions of

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• -Tribromopyrimidine (6a), whose core pyrimidine structure can be found in many biologically active compounds, could be sequentially substituted with 1,3,5-trimethoxybenzene and N-methylpyrrole to give 8a. The protocol also enabled the selective reductive dehalogenation at the benzylic position of 9a with green light

Synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazines via a base-induced rearrangement of functionalized imidazo[4,5-e]thiazolo[2,3-c][1,2,4]triazines

• Dmitry B. Vinogradov,
• Alexei N. Izmest’ev,
• Angelina N. Kravchenko,
• Yuri A. Strelenko and
• Galina A. Gazieva

Beilstein J. Org. Chem. 2023, 19, 1047–1054, doi:10.3762/bjoc.19.80

• rearrangement; 1,3-thiazines; thiazolidine-4-ones; Introduction Nitrogen- and sulfur-containing heterocyclic compounds are widely represented in nature and used for the synthesis of biologically active substances. Among the 1,3-thiazine derivatives, promising compounds as antimicrobial and antiviral drugs

Five new sesquiterpenoids from agarwood of Aquilaria sinensis

• Hong Zhou,
• Xu-Yang Li,
• Hong-Bin Fang,
• He-Zhong Jiang and
• Yong-Xian Cheng

Beilstein J. Org. Chem. 2023, 19, 998–1007, doi:10.3762/bjoc.19.75

• inhibition [8], anti-inflammatory [10], antiasthmatic [11], antidiabetic [12], and antioxidant [13] activities, have been reported for agarwood extracts [14][15]. Our group recently reported five structurally intriguing and biologically active sesquiterpene dimers [16], which attracted our interest to gain

Clauson–Kaas pyrrole synthesis using diverse catalysts: a transition from conventional to greener approach

• Dileep Kumar Singh and
• Rajesh Kumar

Beilstein J. Org. Chem. 2023, 19, 928–955, doi:10.3762/bjoc.19.71

• many natural products [1][2][3] and biologically active molecules [4][5][6][7]. Pyrroles are a significant class of five-membered aromatic nitrogen-containing heterocyclic skeletons that have attracted much attention due to their broad spectrum of biological activity, such as anticancer [8][9][10