Iodine-catalyzed electrophilic substitution of indoles: Synthesis of (un)symmetrical diindolylmethanes with a quaternary carbon center

• Thanigaimalai Pillaiyar,
• Masoud Sedaghati,
• Andhika B. Mahardhika,
• Lukas L. Wendt and
• Christa E. Müller

Beilstein J. Org. Chem. 2021, 17, 1464–1475, doi:10.3762/bjoc.17.102

• biological activities (Figure 1) [10]. Unsubstituted DIM (I), for example, exhibits antimicrobial [5], anticancer [11][12][13], and anti-inflammatory effects (Figure 1) [14]. There is preclinical evidence for activity against several types of cancer [15], and DIM has been clinically evaluated for the

• treatment of prostate cancer [16] and showed promise for the treatment of cervical dysplasia [17]. The related trisindoline (II) was reported to possess antibiotic activity [18], while DIM derivatives III and IV also showed anticancer activities (Figure 1). Owing to their exciting biological activities, DIM

Synthesis of 1-indolyl-3,5,8-substituted γ-carbolines: one-pot solvent-free protocol and biological evaluation

• Premansh Dudhe,
• Mena Asha Krishnan,
• Kratika Yadav,
• Diptendu Roy,
• Krishnan Venkatasubbaiah,
• Biswarup Pathak and
• Venkatesh Chelvam

Beilstein J. Org. Chem. 2021, 17, 1453–1463, doi:10.3762/bjoc.17.101

• cancer cells. Keywords: γ-carboline; cascade reaction; cell uptake; cytotoxicity; fluorescence; Introduction Carbolines are privileged aza-heterocycles found in the core of several natural and synthetic compounds and are known for their biological applications. Among the four different isomers, 9H

• effective against cervical cancer (HeLa cells) [8]. Moreover, γ-carbolines are known for their well-established DNA intercalating [9] and anti-Alzheimer [10] properties. The classical Graebe–Ullmann synthesis [11] of γ-carbolines, one of the very early protocols in the domain, is based on the thermal

• with a standard drug, doxorubicin, were screened for their cytotoxicity against various cancer lines (Figure 5, Table 3 and Figure S2, in Supporting Information File 1) such as MCF-7 (breast cancer), HeLa (cervical cancer), HEK293 (human embryonic kidney cells), A431 (skin cancer), A549 (lung cancer

Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp.

• Birthe Sandargo,
• Leon Kaysan,
• Rémy B. Teponno,
• Christian Richter,
• Benjarong Thongbai,
• Frank Surup and
• Marc Stadler

Beilstein J. Org. Chem. 2021, 17, 1385–1391, doi:10.3762/bjoc.17.97

• cytotoxicity was assessed in vitro against mouse fibroblast cell line L929, cervix carcinoma cell line KB3.1, ovarian cancer cell line SKOV-3, human adenocarcinoma cell lines MCF-7 and PC-3, and human epidermoid carcinoma cell line A431, using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium

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

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

• pancreatic carcinoma and triple-negative breast cancer (Scheme 23B) [55]. Konteatis et al. adopted a similar approach by using the direct fusion for the preparation of bisdifluorocyclic biguanides as IDH1/2 inhibitor intermediates (Scheme 23C) [56]. However, sodium dicyanamide has been mainly used as an

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

• , it has been found that berberine (1a) exhibits a selective cytotoxicity against cancer cells [12][13], which is mainly based on its DNA-binding properties [14]. Since the complexation with DNA leads to significant changes of the fluorescent quantum yields of the bound berberine, it can also be used

Stereoselective synthesis and transformation of pinane-based 2-amino-1,3-diols

• Ákos Bajtel,
• Mounir Raji,
• Matti Haukka,
• Ferenc Fülöp and
• Zsolt Szakonyi

Beilstein J. Org. Chem. 2021, 17, 983–990, doi:10.3762/bjoc.17.80

• very good agonist for the S1P1 receptor (Figure 1). Sphingosine 1-phosphate (S1P, 4), in turn, performed critical regulator functions in many physiological and pathological treatments, such as Alzheimer’s disease [8][9], cancer [10][11][12][13], multiple sclerosis [14], and inflammation [15]. Due to

Application of the Meerwein reaction of 1,4-benzoquinone to a metal-free synthesis of benzofuropyridine analogues

• Rashmi Singh,
• Tomas Horsten,
• Rashmi Prakash,
• Swapan Dey and
• Wim Dehaen

Beilstein J. Org. Chem. 2021, 17, 977–982, doi:10.3762/bjoc.17.79

• cancer cell lines [12][13]. Fluoroquinophenoxazines 2 have been used as telomerase inhibitors in anticancer research [14]. Furthermore, benzofuroisoindoles 3 were part of a kinase inhibitor study [15]. Photobiologically active psoralene (linear furocoumarin) dibenzofurans 1 and angular furanocoumarin

Beyond ribose and phosphate: Selected nucleic acid modifications for structure–function investigations and therapeutic applications

• Christopher Liczner,
• Kieran Duke,
• Gabrielle Juneau,
• Martin Egli and
• Christopher J. Wilds

Beilstein J. Org. Chem. 2021, 17, 908–931, doi:10.3762/bjoc.17.76

• overall steps [164]. ASOs containing these modified nucleosides have demonstrated promising antitumor activity for lymphoma and lung cancer [165]. Numerous other LNA analogues have been constructed including, but not limited to, 2'-N-guanidino,4'-C-ethylene (GENA) (Figure 7I) [166], sulfonamide-bridged

Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides

• Roslyn M. Ray,
• Anders Højgaard Hansen,
• Maria Taskova,
• Bernhard Jandl,
• Jonas Hansen,
• Citra Soemardy,
• Kevin V. Morris and
• Kira Astakhova

Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75

• –maleimide–PEG into their LNPs to target epidermal growth factor receptor (EGFR)-positive cancer cells. The authors showed an increased delivery of siRNAs and fluorescent quantum dot nanocrystals both in vitro and in EGFR-positive tumor xenografts in mice [48]. In 2020, Chandra et al. used a maleimide–PEG in

• their LNP formulation to functionalize LNPs with an aptamer specific for the human epidermal growth factor 2 (HER2) receptor. Therein, functionalized LNPs increased siRNA delivery and subsequent sensitivity of the doxorubicin-resistant HER2-positive breast cancer cell lines by ≈2-fold over LNPs with no

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

• longer reaction time (3 h) with lower yields (60%) as compared to microwave (20 min with 91% yield). The library of molecules synthesized was found to be active against SKOV-3 cancer cells with 9a emerging as a promising molecule with IC50 = 0.24 ± 0.05 μM (Scheme 3). The protocol surfaces the efficiency

• subjecting them to the potential dipolarophile but-2-ynedionates to deliver the target molecules. Both the reactions proceeded well in water aiding in greener synthesis of biologically active molecules. The synthesized molecules exhibited significant activity against human lung cancer cell line A549. A

• cancer cell lines along with good antimicrobial activity (Scheme 24). The proposed mechanism (Scheme 25) involved a Knoevenagel condensation between aldehyde 5 and malononitrile (51) to form arylidene intermediate A. Then A reacts with isocyanide 21 to produce intermediate B which coordinates with 1,10

DNA with zwitterionic and negatively charged phosphate modifications: Formation of DNA triplexes, duplexes and cell uptake studies

• Yongdong Su,
• Maitsetseg Bayarjargal,
• Tracy K. Hale and
• Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2021, 17, 749–761, doi:10.3762/bjoc.17.65

• +{FAM} ON and it was only present in the cytoplasm. These results indicate that ONs with phosphate modifications such as N+ or Ts might be suitable tools for the application of DNA and RNA vaccines [60], for the treatment of cancer [61], infectious diseases [62], and neurological disorders [63

• . Maksim V. Kvach for valuable discussions and suggestions. We also thank Mr. Raoul Solomon for assistance in the preparation of Figure 3 and Figure 4. Funding V.V.F. and Y.S. are grateful for the financial support provided by the School of Fundamental Sciences (Massey University) and Cancer Society of New

Simulating the enzymes of ganglioside biosynthesis with Glycologue

• Andrew G. McDonald and
• Gavin P. Davey

Beilstein J. Org. Chem. 2021, 17, 739–748, doi:10.3762/bjoc.17.64

• ganglioside biosynthesis, and altered ganglioside status in cancer, and the effects on network structure are predicted. The simulator is available at the Glycologue website, https://glycologue.org/. Keywords: gangliosides; Glycologue; glycosyltransferases; neuropathy; Svennerholm nomenclature; Introduction

• disorders of ganglioside biosynthesis can lead to a number of neuropathies, including motor deficits, microcephaly, sensory loss, and autistic features [10][11]. Certain gangliosides, such as GM2, have been identified as tumor markers for breast cancer stem cells [12], while members of the alpha-series

Amino- and polyaminophthalazin-1(2H)-ones: synthesis, coordination properties, and biological activity

• Zbigniew Malinowski,
• Emilia Fornal,
• Agata Sumara,
• Renata Kontek,
• Karol Bukowski,
• Beata Pasternak,
• Dariusz Sroczyński,
• Joachim Kusz,
• Magdalena Małecka and
• Monika Nowak

Beilstein J. Org. Chem. 2021, 17, 558–568, doi:10.3762/bjoc.17.50

• production [11] that plays an important role in the growth of various cancerous tissues (colon, lung, and breast cancer) and as antagonists of the human A3 adenosine receptor [12]. Aminophthalazines have been also evaluated for their inhibitory activity toward phosphodiesterases such as PDE-5 (Figure 1) [13

• cytotoxicity, proliferation and growth of HT-29 (human colon adenocarcinoma cell line), PC-3 (human prostate cancer cell line) and L-929 cells (mouse fibroblast cell line). The results obtained from the MTT assay revealed that the tested phthalazinone derivatives were cytotoxic towards the tested cell lines in

The synthesis of chiral β-naphthyl-β-sulfanyl ketones via enantioselective sulfa-Michael reaction in the presence of a bifunctional cinchona/sulfonamide organocatalyst

• Deniz Tözendemir and
• Cihangir Tanyeli

Beilstein J. Org. Chem. 2021, 17, 494–503, doi:10.3762/bjoc.17.43

• a low (1 mol %) catalyst loading, to obtain enantiomerically enriched β-naphthyl-β-sulfanyl ketones with up to 96% ee. The target adducts are the core structure of seco-raloxifene derivatives, which are potent anti-breast cancer agents [32]. In addition, the same scaffold has also shown urease

• , which have potent activity against breast cancer. The easy access to the corresponding sulfones presents a versatile route for the implementation of a new biologically active moiety, the sulfone, to the β-naphthyl-β-sulfanyl ketones. The enantioenriched products of both classes can be evaluated as

Biochemistry of fluoroprolines: the prospect of making fluorine a bioelement

• Vladimir Kubyshkin,
• Rebecca Davis and
• Nediljko Budisa

Beilstein J. Org. Chem. 2021, 17, 439–460, doi:10.3762/bjoc.17.40

• catabolic degradation of proline plays an important role in the development of cancer cells, making the inhibition of the proline dehydrogenase a promising method in cancer therapy [69][70]. There is no information on a possible intracellular degradation of fluoroprolines, although, they are included in

Synthesis of legonmycins A and B, C(7a)-hydroxylated bacterial pyrrolizidines

• Wilfred J. M. Lewis,
• David M. Shaw and
• Jeremy Robertson

Beilstein J. Org. Chem. 2021, 17, 334–342, doi:10.3762/bjoc.17.31

• cytotoxic against a variety of cancer cell lines, and both bohemamine and NP25302 inhibit HL-60 cell adhesion to Chinese hamster ovary cells expressing intercellular adhesion molecule ICAM-1 (CD-54). This interest led us to develop a total synthesis of NP25302 [25] and its 5-normethyl analog and, as

¹⁹F NMR as a tool in chemical biology

• Diana Gimenez,
• Aoife Phelan,
• Cormac D. Murphy and
• Steven L. Cobb

Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28

• investigated in the presence of cell extracts. Ojima and collaborators have also employed functional ligand-observed NMR experiments to develop a range of novel 3′-difluorovinyltaxoids, such as BLT-F2 and BLT-S-F6 (Figure 5c), that are active against drug-sensitive and multidrug-resistant (MDR) human cancer

• presence of DNA, and another intrinsically disordered binding partner, breast cancer antigen 1 (BRCA1) (Figure 12). In this work the strategy employed involved the introduction of a perfluorinated [19F]3,5‐bis(trifluoromethyl)benzyl-based tag into the single cysteine residue of Myc. This modification

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

Progress in the total synthesis of inthomycins

• Bidyut Kumar Senapati

Beilstein J. Org. Chem. 2021, 17, 58–82, doi:10.3762/bjoc.17.7

• biosynthesis [1][4], in vitro antimicrobial activity [4][5], and anticancer activity against human prostate cancer cell lines [6][7]. A recent study suggested that the close analogue (+)-11 of inthomycin C was found to exhibit proteasome inhibition activity [8]. The skeletal structures of inthomycins A–C (1–3

Control over size, shape, and photonics of self-assembled organic nanocrystals

• Chen Shahar,
• Yaron Tidhar,
• Yunmin Jung,
• Haim Weissman,
• Sidney R. Cohen,
• Ronit Bitton,
• Iddo Pinkas,
• Gilad Haran and
• Boris Rybtchinski

Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5

• Current address: Center for Cancer Immunotherapy, La Jolla Institute for Immunology, La Jolla, CA, U.S.A. Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel Department of Chemical Engineering, Ben-Gurion University, Beer Sheva 84105, Israel Ilse Katz Institute

Molecular basis for protein–protein interactions

• Brandon Charles Seychell and
• Tobias Beck

Beilstein J. Org. Chem. 2021, 17, 1–10, doi:10.3762/bjoc.17.1

• fundamental in proteomics, and the identification of PPIs has the potential to confer new drug targets for diseases, such as cancer. As a result, research involving PPIs is imperative for our biological knowledge and future aspects in medicine. Different methodologies employed to study PPIs. The protein used

Chemical constituents of Chaenomeles sinensis twigs and their biological activity

• Joon Min Cha,
• Dong Hyun Kim,
• Lalita Subedi,
• Zahra Khan,
• Sang Un Choi,
• Sun Yeou Kim and
• Chung Sub Kim

Beilstein J. Org. Chem. 2020, 16, 3078–3085, doi:10.3762/bjoc.16.257

• effects including cytotoxicity against cancer cell lines, antineuroinflammatory activity, and potential neurotrophic effect were evaluated. Keywords: antineuroinflammation; Chaenomeles sinensis; cytotoxicity; megastigmane; neurotrophic effect; Introduction Chaenomeles sinensis (Thouin) Koehne (Rosaceae

• . Cytotoxicity of compounds 9–11 against four cultured human cancer cell lines in the SRB bioassay. Inhibitory effects of compounds 1–12 on the NO production in LPS-activated BV-2 cells. Effects of compounds 1–12 on the NGF secretion in C6 cells. Supporting Information Supporting Information File 398: 1D and 2D

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

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

• involved in a variety of human diseases like cancer, Alzheimer’s, and Parkinson diseases etc. [46]. Therefore, the Schmuck group in collaboration with the Ottmann group sought to develop fluorescent probes (7 and 8) for monitoring of 14-3-3 proteins (Figure 7) [47]. These probes contain two symmetric GCP

Fluorine effect in nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-β-D-hexopyranose

• Danny Lainé,
• Vincent Denavit,
• Olivier Lessard,
• Laurie Carrier,
• Charles-Émile Fecteau,
• Paul A. Johnson and
• Denis Giguère

Beilstein J. Org. Chem. 2020, 16, 2880–2887, doi:10.3762/bjoc.16.237

• ; polyfluorinated carbohydrates; polyfluoroalditol analogues; Introduction The biological significance of carbohydrates includes, but are not limited to, immune regulation, infection, and cancer metastasis. Research in the field of molecular biology allowed the discovery of glycomimetics to study various