Photoredox catalysis enabling decarboxylative radical cyclization of γ,γ-dimethylallyltryptophan (DMAT) derivatives: formal synthesis of 6,7-secoagroclavine

• Alessio Regni,
• Francesca Bartoccini and
• Giovanni Piersanti

Beilstein J. Org. Chem. 2023, 19, 918–927, doi:10.3762/bjoc.19.70

• ][32][33], modification of biomacromolecules [34], and relatively complex pharmaceutical agents [35][36][37][38]. Photocatalysis tremendously enriches the synthetic compound library, providing a precious alternative to directly modify abundant natural substrates, including biomass, which usually

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• yields generating a library of isonicotinic and nicotinic acid derivatives. Another inexpensive and non-toxic iron-catalyzed C–H arylation of pyridines has been reported by DeBeof and co-workers [98]. Using the imine in 147 as directing group, afforded the arylated pyridine products 150 in good to high

Synthesis of imidazo[1,2-a]pyridine-containing peptidomimetics by tandem of Groebke–Blackburn–Bienaymé and Ugi reactions

• Oleksandr V. Kolomiiets,
• Alexander V. Tsygankov,
• Maryna N. Kornet,
• Aleksander A. Brazhko,
• Vladimir I. Musatov and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2023, 19, 727–735, doi:10.3762/bjoc.19.53

• ]pyridine and peptidomimetic moieties as pharmacophores with four diversity points introduced from readily available starting materials, including scaffold diversity. A small focused compound library of 20 Ugi products was prepared and screened for antibacterial activity. Keywords: Groebke–Blackburn

• manner. A method for the synthesis of the desired compounds was developed, and a small library of 20 Ugi products was prepared. The study also demonstrated that the use of a CH2O linker between the carboxyl group and the aryl ring in the Ugi reaction enhanced the reactivity of the acid component. The

• of new acids containing a substituted imidazo[1,2-a]pyridine fragment without CH2O linker fragment. Library of peptidomimetics 7a–t containing a substituted imidazo[1,2-a]pyridine fragment. Screening conditions for synthesis of peptidomimetic 9а and 9b. Antibacterial activity results. Supporting

Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis

• Nicoleta G. Hădărugă,
• Gabriela Popescu,
• Dina Gligor (Pane),
• Cristina L. Mitroi,
• Sorin M. Stanciu and
• Daniel Ioan Hădărugă

Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30

• FAME standard mixture. Moreover, the experimental MS spectra were compared with those from the NIST/EPA/NIH Mass Spectral Library 2.0 (2011). Acquisition and handling of the GC–MS data were performed using the Enhanced MSD ChemStation D.02.00.275 (Agilent Technologies, Santa Clara, CA, USA), while the

• MS identification was performed with the NIST Mass Spectral Search Program for the NIST/EPA/NIH Mass Spectral Library 2.0 (Gaithersburg, MD, USA). Determinations were performed in duplicate and the main findings reveal a high oleic acid relative content (as methyl ester) of 69.91(± 4.14) % at a RI of

Synthesis, α-mannosidase inhibition studies and molecular modeling of 1,4-imino-ᴅ-lyxitols and their C-5-altered N-arylalkyl derivatives

• Martin Kalník,
• Sergej Šesták,
• Juraj Kóňa,
• Maroš Bella and
• Monika Poláková

Beilstein J. Org. Chem. 2023, 19, 282–293, doi:10.3762/bjoc.19.24

• than parent DIM [15]. Also, screening of a large library of N-alkyl and N-arylalkyl DIMs revealed that they are less effective inhibitors of JBMan than DIM, indicating that N-alkylation might lead to better selectivity profiles. However, this library has not been assayed for GMII and LM, therefore the

• -imino-ᴅ-lyxitol which configurationally better resembles swainsonine or DIM. The most promising N-substituents from the previous study were selected and a small library of N-substituted 1,4-imino-ᴅ-lyxitols was prepared [22] (Figure 1). In addition, more relevant Caenorhabditis elegans α-mannosidase II

An efficient metal-free and catalyst-free C–S/C–O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides

• Shubham Sharma,
• Dharmender Singh,
• Sunit Kumar,
• Vaishali,
• Rahul Jamra,
• Naveen Banyal,
• Deepika,
• Chandi C. Malakar and
• Virender Singh

Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22

• , due to various biological activities [36][37][38][39]. Accordingly, a broad spectrum of effective and useful methods has been acknowledged in the literature for their preparation [40][41][42]. In this regard, a review article by Jagodzinski et al. based on the examination of a massive virtual library

Synthesis and characterisation of new antimalarial fluorinated triazolopyrazine compounds

• Kah Yean Lum,
• Jonathan M. White,
• Daniel J. G. Johnson,
• Vicky M. Avery and
• Rohan A. Davis

Beilstein J. Org. Chem. 2023, 19, 107–114, doi:10.3762/bjoc.19.11

• yields. This paper reports additional and more thorough Diversinate™ studies on three phenethyl ether substituted triazolopyrazine scaffolds, with a particular focus on incorporating the fluoro fragments -CF3, -CF2H and -CF2Me into the OSM Series 4 structures via LSF chemistry. The new library of

Combining the best of both worlds: radical-based divergent total synthesis

• Kyriaki Gennaiou,
• Antonios Kelesidis,
• Maria Kourgiantaki and
• Alexandros L. Zografos

Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1

• libraries. But how big should this chemical space be, so as to actually address our needs? A general consensus has emerged, supporting that “it is not actually the library size but rather the library diversity in terms of molecular structure and function which is fundamental for a successful drug discovery

Using UHPLC–MS profiling for the discovery of new sponge-derived metabolites and anthelmintic screening of the NatureBank bromotyrosine library

• Sasha Hayes,
• Aya C. Taki,
• Kah Yean Lum,
• Joseph J. Byrne,
• Merrick G. Ekins,
• Robin B. Gasser and
• Rohan A. Davis

Beilstein J. Org. Chem. 2022, 18, 1544–1552, doi:10.3762/bjoc.18.164

• , 3010, Australia Biodiversity and Geosciences, Queensland Museum, Grey Street, Brisbane, 4101, Australia 10.3762/bjoc.18.164 Abstract In order to further expand the NatureBank open access compound library, chemical investigations of the Australian marine sponge, Ianthella basta, were undertaken since

• marine natural product, ianthesine E (2). The chemical structure of the new compound was determined following detailed spectroscopic and spectrometric data analysis. These two compounds (1 and 2) along with seven previously reported marine bromotyrosine alkaloids from the NatureBank open access library

• ], antibacterial [7][8], antimalarial [9], anti-HIV [10] and antifouling activities [11]. Due to our continuing interest in the identification of new secondary metabolites from Australian marine sources, in addition to further expanding the NatureBank [12] open access compound library, we have recently embarked on

Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface

• Kendra Drayton-White,
• Siyue Liu,
• Yu-Chia Chang,
• Sakashi Uppal and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156

• -time data on binding events appear ideal for such an iterative study. However, to use a microelectrode array in this fashion requires that the molecules being synthesized be added to the surface of an array as they become available, and then the growing library analyzed in a manner that allows the

Oxa-Michael-initiated cascade reactions of levoglucosenone

• Julian Klepp,
• Thomas Bousfield,
• Hugh Cummins,
• Sarah V. A.-M. Legendre,
• Jason E. Camp and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2022, 18, 1457–1462, doi:10.3762/bjoc.18.151

• ]. These types of oxa-Michael initiated aldol condensations were also of interest to us due to the previous work conducted on aldol adducts of 1 [14][21], and the potential to generate bio-derived chiral materials with reactive functional groups. We envisaged that the development of a larger library of

Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides

• Shengli Zuo,
• Shuxiang Zheng,
• Jianjun Liu and
• Ang Zuo

Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147

• as an enantioselective catalyst for the asymmetric ring opening of terminal epoxides by phenols. A library of α-aryloxy alcohols 3 was thereafter synthesized in good yield and high ee using 2f via the phenolic KR of epichlorohydrin. Keywords: α-aryloxy alcohols; chiral Co–salen; HKR

• in both techniques and probably pressure-induced activation and shearing deformation of reactant particles are more efficient using the grinding. We next examined the chelating effect of the above salens 1 with different transition metals. A library of metal–salen complexes was synthesized as

• intimate affinity of unsymmetrical salens chelating with metals. The HKR of epichlorohydrin with water catalyzed by Co–salens 2 was studied and chiral 2f showed an outstanding catalytic ability to afford the diol product in high ee (98%). A library of α-aryloxy alcohols was thereafter synthesized through

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• considering the results of academic as well as industrial screening campaigns. Keywords: antibacterials; frequent hitters; hit to lead chemical library; medicinal chemistry; virtual docking; Introduction The current state of affairs in the academia and two problems for medicinal chemists Across the world

• experiments following the screening of a library [51][52]. However, many of these compounds, often of natural origin [53]; polyphenols and curcumin being emblematic [54], are the bread and butter of quack medicine. Indeed, these will be found active on many biochemical or cellular assays [46] and will thus

• with a structural diversity are also prominent factors chosen for the ESCulab library made available by the European Lead Factory initiative [99]. Concerning this minimum of related compounds to include in an assay, it is likely stemming from Ulf Norinder’s probability-based illustration of the issues

Dienophilic reactivity of 2-phosphaindolizines: a conceptual DFT investigation

• Nosheen Beig,
• Aarti Peswani and
• Raj Kumar Bansal

Beilstein J. Org. Chem. 2022, 18, 1217–1224, doi:10.3762/bjoc.18.127

• , which was named as 2-phosphaindolizine perceiving it to result from a formal CH/P exchange at the 2-position of indolizine (2) (Figure 1) [1]. Subsequently a good library of these interesting compounds became accessible [1]. The methodology could be extended successfully to the synthesis of 1,3,4

Experimental and theoretical studies on the synthesis of 1,4,5-trisubstituted pyrrolidine-2,3-diones

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Nguyen Ngoc Tri,
• Luc Van Meervelt,
• Nguyen Tien Trung and
• Wim Dehaen

Beilstein J. Org. Chem. 2022, 18, 1140–1153, doi:10.3762/bjoc.18.118

• -acetyl-3-hydroxy-3-pyrroline-2-ones via multicomponent reactions of ethyl 2,4-dioxovalerate with aromatic aldehydes, and aniline in glacial acetic acid. These 2-pyrrolidinone derivatives were then reacted with aliphatic amines in ethanol to obtain a library of 1,4,5-trisubstituted pyrrolidine-2,3-dione

• (kcal·mol−1) at the B3LYP/6-311++G(2d,2p)// B3LYP/6-31+G(d,p) level of theory. Optimization of the reaction conditions for the synthesis of compound 10aa. Synthesis of a library of 1,4,5-trisubstituted pyrrolidine-2,3-diones. Supporting Information Supporting Information File 188: Experimental part

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• ) triazoloquinoxaline complexes as well as a new TIQ rhenium complex were synthesized. As a result, a small 1,2,3-triazoloquinoxaline library was obtained and the method could be expanded towards 4-substituted tetrazoloquinoxalines. The compatibility of various aliphatic and aromatic alkynes towards the reaction was

• , a small library of 1,2,3-triazole-substituted quinoxalines was synthesized applying the method of Chattopadhyay et al. [10] with minor adjustments. Altogether, a series of 21 different aliphatic and aromatic terminal alkynes were reacted with tetrazolo[1,5-a]quinoxaline and Cu(I) triflate as a

Isolation and biosynthesis of daturamycins from Streptomyces sp. KIB-H1544

• Yin Chen,
• Jinqiu Ren,
• Ruimin Yang,
• Jie Li,
• Sheng-Xiong Huang and
• Yijun Yan

Beilstein J. Org. Chem. 2022, 18, 1009–1016, doi:10.3762/bjoc.18.101

• ) values were 0.1059 (I > 2σ(I)). The final R1 values were 0.0495 (all data). The final wR(F2) values were 0.1101 (all data). The goodness of fit on F2 was 1.051. Genomic library construction and screening The genome of S. sp. KIB-H1544 was sequenced through the Illumina Genome Analyzer (Illumina, San

Morita–Baylis–Hillman reaction of 3-formyl-9H-pyrido[3,4-b]indoles and fluorescence studies of the products

• Nisha Devi and
• Virender Singh

Beilstein J. Org. Chem. 2022, 18, 926–934, doi:10.3762/bjoc.18.92

• transformation than 6e. It is noteworthy here that all the products were purified by column chromatography. A small library of C-3-substituted pyrido[3,4-b]indole derivatives was designed and synthesized which is presented in Figure 4. All the products were characterized using NMR, FTIR and mass spectrometry

• substituted frameworks. A summary of previous reports toward exploration of 3-formyl-9H-β-carbolines. Library of C-3-substituted pyrido[3,4-b]indole MBH derivatives 7, 8 and 10. Results of optimization for fluorescence studies: a) contact time; b) concentration; c) solvent. Pictorial representation of

Efficient production of clerodane and ent-kaurane diterpenes through truncated artificial pathways in Escherichia coli

• Fang-Ru Li,
• Xiaoxu Lin,
• Qian Yang,
• Ning-Hua Tan and
• Liao-Bin Dong

Beilstein J. Org. Chem. 2022, 18, 881–888, doi:10.3762/bjoc.18.89

• , as well as two possible producers (Streptomyces sp. San01 and Kitasatospora sp. CB02891) after a survey of the existing genome sequence databases, however, we discovered a strain, Kitasatosporia griseola DSM 43859, without a genome sequence disclosed, from the strain library of CGMCC. Using the

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

• Anas J. Rasras,
• Mohamed El-Naggar,
• Nesreen A. Safwat and
• Raed A. Al-Qawasmeh

Beilstein J. Org. Chem. 2022, 18, 631–638, doi:10.3762/bjoc.18.63

• 27272, Sharjah, United Arab Emirates The Regional Center for Mycology and Biotechnology, Al-Azhar University, Nasr City, Cairo, 11371, Egypt Department of Chemistry, The University of Jordan, Amman 11942, Jordan 10.3762/bjoc.18.63 Abstract A new chemical library based on the hybridization of cholic

• ]. Having oxadiazole-2-thiol 2 at hands, the reactive thiol was subjected to the reaction with propargyl bromide and sodium carbonate as a base to afford the thiopropargylated derivative 3 in 82% yield after 24 h (Scheme 2) [33]. Compound 3 was the starting point for a Mannich reaction to generate a library

• chemical library based on the hybridization of cholic acid with the heterocyclic moiety 1,3,4-oxadizole was synthesized. All new compounds were unambiguously characterized by various spectroscopic techniques. The newly synthesized compounds were assessed in vitro for their antimicrobial activities

Regioselective synthesis of methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates as new amino acid-like building blocks

• Jolita Bruzgulienė,
• Greta Račkauskienė,
• Aurimas Bieliauskas,
• Vaida Milišiūnaitė,
• Miglė Dagilienė,
• Gita Matulevičiūtė,
• Vytas Martynaitis,
• Sonata Krikštolaitytė,
• Frank A. Sløk and
• Algirdas Šačkus

Beilstein J. Org. Chem. 2022, 18, 102–109, doi:10.3762/bjoc.18.11

• -4-carboxylic acid residue was identified directly from the 12.6-million-member DNA-encoded small molecule library using yoctoReactor technology [26]. We have developed efficient protocols that provide easy access to highly functional heterocyclic compounds as novel amino acid-like building blocks by

Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

• Hendrik Gruß,
• Rebecca C. Feiner,
• Ridhiwan Mseya,
• David C. Schröder,
• Michał Jewgiński,
• Kristian M. Müller,
• Rafał Latajka,
• Antoine Marion and
• Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

• + 7 for two helix turns, respectively, followed by Ru-catalysed cross-linking [7]. By this robust and reliable approach, a library of stapled peptides was generated influencing diverse α-helical dominated protein–protein interactions (PPI) spanning pathways involved in cancer, infectious diseases

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

• . Lineu Prestes 1524, 05508-900 São Paulo-SP, Brazil 10.3762/bjoc.17.206 Abstract Microwave-mediated N-arylation of 4-chloroquinazolines in THF/H2O rapidly and efficiently afforded a library of novel 6-halo-2-phenyl-substituted 4-anilinoquinazolines. The methodology was compatible with numerous ortho

• at C6 as substituents in quinazoline ring has been related to increased antiproliferative action of this class of compounds [28]. Therefore, we wish to report the preparation of a library of novel quinazoline-based antitumor candidates through reaction of 4-chloro-6-halo-2-phenylquinazolines with

• at optimizing the activity of compound 10b and better understanding its mechanism of action and selectivity are underway in our research group. Conclusion We have synthesized a library of novel 6-halo-2-phenyl-substituted 4-anilinoquinazolines through N-arylation of 4-chloro-substituted substrates

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

• potential targets for the versatile pyrazolo[1,2,3]triazine library presented herein. Conclusion In analogy to literature-known acid-induced conversions of triazene-benzyl acetamides to 3,4-dihydrobenzo[d][1,2,3]triazines, so far not described pyrazolo[3,4-d][1,2,3]-3H-triazines 5 were successfully

In-depth characterization of self-healing polymers based on π–π interactions

• Josefine Meurer,
• Julian Hniopek,
• Johannes Ahner,
• Michael Schmitt,
• Jürgen Popp,
• Stefan Zechel,
• Kalina Peneva and
• Martin D. Hager

Beilstein J. Org. Chem. 2021, 17, 2496–2504, doi:10.3762/bjoc.17.166

• controlled program was developed, which mainly uses the well-established data analysis library pandas as well as the SciPy and NumPy libraries for linear algebra, integration and interpolation. Polymer synthesis The polymer synthesis was adapted from literature [23] and is reported briefly in the following