Synthesis of sulfur karrikin bioisosteres as potential neuroprotectives

• Martin Pošta,
• Václav Zima,
• Lenka Poštová Slavětínská,
• Marika Matoušová and
• Petr Beier

Beilstein J. Org. Chem. 2022, 18, 549–554, doi:10.3762/bjoc.18.57

• novel drugs could be the smoke of burning plants that contains more than 4000 chemical species [1] and among them numerous compounds possess biological activities in humans. The psychotropic effect of smoke is well known for centuries and its inhalation has different effects depending on plant material

• methodology for the preparation of analogues of karrikins with one sulfur atom in position C2 or position 6, or two sulfur atoms in both positions was improved; however, observed biological activities towards AChE were rather low. Structures of naturally occurring karrikins. Target compounds with highlighted

Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities

• Viktor A. Zapol’skii,
• Isabell Berneburg,
• Ursula Bilitewski,
• Melissa Dillenberger,
• Katja Becker,
• Stefan Jungwirth,
• Aditya Shekhar,
• Bastian Krueger and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54

• with four different substituents: in position 1 of the pyrazol cycle a 7-chloroquinolin-4-yl unit, in position 3 various amino or thio fragments, in position 4 a nitro and in position 5 a dichloromethyl group. Some biological activities of 7-chloroquinolinyl-substituted pyrazole derivatives have

Tosylhydrazine-promoted self-conjugate reduction–Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives

• Sayan Pramanik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 469–478, doi:10.3762/bjoc.18.49

• important structural motif that is embodied in a number of bioactive natural products and medicinally relevant compounds [1][2]. Among various spirooxindole motifs, bispirooxindoles fusing two spirooxindole cores exhibit a wide range of important biological activities, for example, anticancer

Synthesis of 3,4,5-trisubstituted isoxazoles in water via a [3 + 2]-cycloaddition of nitrile oxides and 1,3-diketones, β-ketoesters, or β-ketoamides

• Md Imran Hossain,
• Md Imdadul H. Khan,
• Seong Jong Kim and
• Hoang V. Le

Beilstein J. Org. Chem. 2022, 18, 446–458, doi:10.3762/bjoc.18.47

• chlorides to form furoxans also known as 1,2,5-oxadiazole 2-oxides, a class of structures with important biological activities due to their unique electronic nature and coordination ability. Keywords: environmentally friendly; furoxans; 1,2,5-oxadiazole 2-oxides; trifluoromethyl-substituted isoxazoles

• and γ-amino alcohols [1]. Isoxazoles, appearing in 33 patents from the year 2016 to 2018 [3], are an important drug class due to their wide range of biological activities, such as anticancer [5], antibiotic [6][7], antimicrobial [8], antifungal [9], and anti-inflammatory [10]. Therefore, new methods

• donors have shown important biological activities due to their unique electronic and coordination ability [37][38], such as antitumor [39] and antiparasitic [40][41]. Previously, furoxans were synthesized via dimerization of hydroximoyl chlorides in the presence of a base, such as trimethylamine in ether

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• shown a wide range of biological activities of menadione, such as anticancer [15][16][17][18][19][20][21][22], antibacterial [23][24][25][26], antifungal [27][28], antimalarial [29][30][31][32], antichagasic [33], and anthelmintic [34] effects. In these cases, the redox cycle of menadione, followed by

• ][41]. The quinone–hydroquinone and quinone–semiquinone interconversions, with ROS generation, are responsible for the wide range of biological activities of menadione and its derivatives. An excess of ROS in the intracellular environment can cause harmful effects on structures such as nucleic acids

Unexpected chiral vicinal tetrasubstituted diamines via borylcopper-mediated homocoupling of isatin imines

• Marco Manenti,
• Leonardo Lo Presti,
• Giorgio Molteni and
• Alessandra Silvani

Beilstein J. Org. Chem. 2022, 18, 303–308, doi:10.3762/bjoc.18.34

• commonly utilized as key intermediates for the synthesis of boron-containing peptidomimetics, which have been demonstrated to be efficient covalent ligands and valuable protease inhibitors endowed with various biological activities [5][6]. Going on with our interest in the synthesis of 3,3-disubstituted

• in 2014 [16]. Herein, we describe the unexpected results achieved by our work, that is the obtainment of unprecedented, bisoxindole-based, vicinal, tetrasubstituted diamines. Bisoxindoles represent a particularly intriguing class of compounds, because of their interesting biological activities and

New efficient synthesis of polysubstituted 3,4-dihydroquinazolines and 4H-3,1-benzothiazines through a Passerini/Staudinger/aza-Wittig/addition/nucleophilic substitution sequence

• Long Zhao,
• Mao-Lin Yang,
• Min Liu and
• Ming-Wu Ding

Beilstein J. Org. Chem. 2022, 18, 286–292, doi:10.3762/bjoc.18.32

• biological activities, including anticancer [9], neuroprotective [10], antiproliferative and antifungal activities [11]. Due to the significant bioactive properties of the 3,4-dihydroquinazoline and 4H-3,1-benzothiazine moieties, many preparation procedures have appeared in the literature for the synthesis

Glycosylated coumarins, flavonoids, lignans and phenylpropanoids from Wikstroemia nutans and their biological activities

• Meifang Wu,
• Xiangdong Su,
• Yichuang Wu,
• Yuanjing Luo,
• Ying Guo and
• Yongbo Xue

Beilstein J. Org. Chem. 2022, 18, 200–207, doi:10.3762/bjoc.18.23

• identification of a new bis-coumarin glucoside 1, together with three known bis- and tricoumarin glucosides 2–4, two flavonoid glycosides 5 and 6, and eleven lignan glucosides 7–17 (Figure 1). Herein, we present the isolation and structural elucidation of these natural products and their in vitro biological

• activities. Results and Discussion Compound 1 was obtained as a yellowish, amorphous powder. Its molecular formula was determined as C29H28O15 based on the HRESIMS sodium adduct ion observed at m/z 639.1319 ([M + Na]+, calcd for C29H28O15Na+, 639.1320), indicating sixteen degrees of unsaturation. Its UV

Synthesis and late stage modifications of Cyl derivatives

• Phil Servatius and
• Uli Kazmaier

Beilstein J. Org. Chem. 2022, 18, 174–181, doi:10.3762/bjoc.18.19

• , such as histone deacetylases. Keywords: chelated enolate; Claisen rearrangement; HDAC inhibitor; peptide; late stage modification; Introduction Among natural products, peptidic structures have entered the limelight due to their extraordinary biological activities [1]. Often found as secondary

Efficient and regioselective synthesis of dihydroxy-substituted 2-aminocyclooctane-1-carboxylic acid and its bicyclic derivatives

• İlknur Polat,
• Selçuk Eşsiz,
• Uğur Bozkaya and
• Emine Salamci

Beilstein J. Org. Chem. 2022, 18, 77–85, doi:10.3762/bjoc.18.7

• biological activities, especially applications in the field of medicinal chemistry. β-Amino acids (i.e., amino acids containing an extra methylene group in the backbone) occur naturally in peptidic structures [1][2][3][4][5] and have been used in peptide design to obtain mixed peptides that retain their

• biological activities [6][7]. Moreover, they can be used as starting substances for different heterocycles, as precursors for the synthesis of polymers, as potential pharmacons, for the synthesis of natural products or analogues, and also as building blocks in drug research [8][9][10][11]. Furthermore, some

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• used in organic synthesis, they are excellent analytical derivatization reagents to spectrophotometrically determine drugs containing primary and secondary amino groups. This review summarizes the literature involving β-NQS. Keywords: biological activities; derivatization reagents; β-NQS; organic

• synthesis; Introduction The general class of quinones is very important because their compounds show biological activities against several pathogens related to important diseases and are used for the production of special materials [1][2][3][4]. These compounds are biosynthesized by oxidative processes of

• oxidative processes in aerobic metabolism, photosynthesis, oxidative phosphorylation, blood clotting, and other electron transport reactions [7][8]. These biochemical functions give them several biological activities, such as antibacterial, fungicidal, antimalarial, trypanocidal, and antitumor. For this

Efficient N-arylation of 4-chloroquinazolines en route to novel 4-anilinoquinazolines as potential anticancer agents

• Rodolfo H. V. Nishimura,
• Thiago dos Santos,
• Valter E. Murie,
• Luciana C. Furtado,
• Leticia V. Costa-Lotufo and
• Giuliano C. Clososki

Beilstein J. Org. Chem. 2021, 17, 2968–2975, doi:10.3762/bjoc.17.206

• ) with relevant biological activities, is recognized as a privileged scaffold in medicinal chemistry [3][4]. Among important quinazoline derivatives, 4-anilinoquinazolines have been widely investigated as antitumor agents because they can inhibit some receptor tyrosine kinases (RTKs) expressed by

Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases

• Inaiá O. Rocha,
• Yuri G. Kappenberg,
• Wilian C. Rosa,
• Clarissa P. Frizzo,
• Nilo Zanatta,
• Marcos A. P. Martins,
• Isadora Tisoco,
• Bernardo A. Iglesias and
• Helio G. Bonacorso

Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191

• imines, Schiff bases have the general organic function -C=N- [2], and are known to have a wide range of biological activities, including antioxidant [3], antitubercular [4], antibacterial [5], antimicrobial [6], and antifungal properties [7], in addition to their role as chemosensors [8] (Figure 1

Synthesis of new pyrazolo[1,2,3]triazines by cyclative cleavage of pyrazolyltriazenes

• Nicolai Wippert,
• Martin Nieger,
• Claudine Herlan,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2021, 17, 2773–2780, doi:10.3762/bjoc.17.187

• ; triazenes; triazines; Introduction The structural motif of pyrazolotriazines, particularly the pyrazolotriazinones, has drawn attention regarding a possible application as therapeutic agents due to manifold biological activities. Amongst other known constitutional isomers such as pyrazolo[4,3-e][1,2,4

Recent advances in the asymmetric phosphoric acid-catalyzed synthesis of axially chiral compounds

• Alemayehu Gashaw Woldegiorgis and
• Xufeng Lin

Beilstein J. Org. Chem. 2021, 17, 2729–2764, doi:10.3762/bjoc.17.185

• moderate yield with >90% enantioselectivity (Scheme 20c) and tolerable diastereoselectivity (4:1) [73]. The optically enriched benzimidazoles are N-heterocycles which are of great interest as drug-like molecules [75], and exhibit biological activities such as anticancer, antiviral, antifungal, and

The ethoxycarbonyl group as both activating and protective group in N-acyl-Pictet–Spengler reactions using methoxystyrenes. A short approach to racemic 1-benzyltetrahydroisoquinoline alkaloids

• Marco Keller,
• Karl Sauvageot-Witzku,
• Franz Geisslinger,
• Nicole Urban,
• Michael Schaefer,
• Karin Bartel and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2716–2725, doi:10.3762/bjoc.17.183

• alkaloids). The common biosynthetic origin of these alkaloids has been investigated thoroughly over decades, and (S)-norcoclaurine, a metabolite formally built up by condensation of dopamine and 4-hydroxyphenylacetaldehyde, was identified as the common intermediate. A broad range of biological activities

• for effects on cation channels and the VCR-R CEM tumor cell line. As expected, the ten alkaloids did not block the cation channel TPC2, and this result confirms former evidence on structure–activity relationships on this target. In line with that, testing for biological activities of the novel

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• results in the formation of the 1,3-oxathiolane species 63 (Scheme 20). Enzymatic approaches 1,3-Oxathiolanes have shown broad biological activities, including the most important intermediates in the synthesis of the pharmaceuticals lamivudine (1) and emtricitabine (2), which have been approved as drugs

Synthesis of highly substituted fluorenones via metal-free TBHP-promoted oxidative cyclization of 2-(aminomethyl)biphenyls. Application to the total synthesis of nobilone

• Ilya A. P. Jourjine,
• Lukas Zeisel,
• Jürgen Krauß and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2668–2679, doi:10.3762/bjoc.17.181

• identified (Scheme 1). However, a couple of structure assignments had to be revised, mostly based on results from total syntheses [4][5]. Numerous biological activities have been reported for natural fluorenones, e.g., antioxidative properties of dendroflorin (1c) and nobilone (1d) [6], antiischemic activity

Solvent-free synthesis of enantioenriched β-silyl nitroalkanes under organocatalytic conditions

• Akhil K. Dubey and
• Raghunath Chowdhury

Beilstein J. Org. Chem. 2021, 17, 2642–2649, doi:10.3762/bjoc.17.177

• enantioselectivity (52% ee). β-Silylenone 2n bearing a o-chloro substituent in the aromatic ring remained unreactive under the optimized reaction conditions probably due to steric hindrance. The facile synthesis of both enantiomers of the targeted compounds is of paramount importance since biological activities are

α-Ketol and α-iminol rearrangements in synthetic organic and biosynthetic reactions

• Scott Benz and
• Andrew S. Murkin

Beilstein J. Org. Chem. 2021, 17, 2570–2584, doi:10.3762/bjoc.17.172

• with diverse biological activities [17]. The key step first involved the rhodium carbenoid-mediated OH insertion/Claisen rearrangement following complexation of diazoester 56 and allylic alcohol 57 to produce intermediate 58 (Figure 13). Addition of BF3·OEt2 to the reaction mixture then catalyzed the α

Recent advances in the tandem annulation of 1,3-enynes to functionalized pyridine and pyrrole derivatives

• Yi Liu,
• Puying Luo,
• Yang Fu,
• Tianxin Hao,
• Xuan Liu,
• Qiuping Ding and
• Yiyuan Peng

Beilstein J. Org. Chem. 2021, 17, 2462–2476, doi:10.3762/bjoc.17.163

• % yield) and monodesulfonated nicotinate 17 (in 70% yield), respectively (Scheme 6). Selenyl- and sulfenylpyridine derivatives are gaining prominence due to the prospective biological activities. They could be used for treatment of HIV, cancer, inflammation, and microbial infection. Therefore, the

• products with potential biological activities or pharmacological activities. For instance, longanlactone, zomepirac (Zomax), ketorolac and pollenopyrroside A are pyrrole derivatives bearing a 2-carbonyl group. Therefore, the synthesis of such kinds of pyrrole derivatives is highly valuable. In 2017, Baire

• derivatives and the other is 5-exo-dig cyclization to afford the pyrrole derivatives. Considering the good biological activities and the wide applicability in synthetic organic chemistry, biopharmaceuticals, and materials, it is desirable to develop more efficient methods for the synthesis of diverse

Strategies for the synthesis of brevipolides

• Yudhi D. Kurniawan and
• A'liyatur Rosyidah

Beilstein J. Org. Chem. 2021, 17, 2399–2416, doi:10.3762/bjoc.17.157

• -dihydro-α-pyrone derivatives, bearing either a distinctive cyclopropane or furan ring and named brevipolides A–O (1–15), have been isolated from the invasive plant Hyptis brevipes Poit. Their fascinating structural features, and the potent biological activities, including cytotoxicity against an array of

• human cancer cell lines and inhibition of the chemokine receptor CCR5, make them attractive synthetic targets. This review article highlights the recent synthetic methodologies and briefly summarizes their biological activities. Keywords: brevipolides; 5,6-dihydro-α-pyrone; Furukawa-modified Simmons

• immunodeficiency virus (HIV). The newly discovered brevipolides with interesting structural features in conjunction with promising biological activities have prompted the researchers to conduct synthetic studies. To date, there are six reported works in the literature for the syntheses of brevipolides, with the

Synthesis and antimicrobial activity of 1H-1,2,3-triazole and carboxylate analogues of metronidazole

• Satya Kumar Avula,
• Syed Raza Shah,
• Khdija Al-Hosni,
• Muhammad U. Anwar,
• Rene Csuk,
• Biswanath Das and
• Ahmed Al-Harrasi

Beilstein J. Org. Chem. 2021, 17, 2377–2384, doi:10.3762/bjoc.17.154

• metronidazole scaffolds are known to have a large range of biological activities including tumorhypxia agents [8], antiprotozoal activity [9], antimicrobial [10], antitumour [11], carbonic anhydrase IX inhibitors [12], trichomonas vaginalis activity [13], antileishmanial agents [14] (Figure 2). We have recently

• synthesized several 1H-1,2,3-triazole-containing molecules with impressive biological activities [15]. In continuation of our research work on 1H-1,2,3-triazole derivatives [16], we have synthesized a series of new 1H-1,2,3-triazole and carboxylate derivatives of metronidazole (5a–i and 7a–e). The choice of

Phenolic constituents from twigs of Aleurites fordii and their biological activities

• Kyoung Jin Park,
• Won Se Suh,
• Da Hye Yoon,
• Chung Sub Kim,
• Sun Yeou Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2021, 17, 2329–2339, doi:10.3762/bjoc.17.151

Nomimicins B–D, new tetronate-class polyketides from a marine-derived actinomycete of the genus Actinomadura

• Zhiwei Zhang,
• Tao Zhou,
• Taehui Yang,
• Keisuke Fukaya,
• Enjuro Harunari,
• Shun Saito,
• Katsuhisa Yamada,
• Chiaki Imada,
• Daisuke Urabe and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2194–2202, doi:10.3762/bjoc.17.141

• actinomycete of the genus Actinomadura. We herein describe the isolation, structure determination, and biological activities of 1‒3. Results and Discussion The producing strain Actinomadura sp. AKA43 was isolated from DSW collected at a depth of −800 m in Sagami Bay, Japan. Strain AKA43 was cultured in A16