Methodology for awakening the potential secondary metabolic capacity in actinomycetes

• Shun Saito and
• Midori A. Arai

Beilstein J. Org. Chem. 2024, 20, 753–766, doi:10.3762/bjoc.20.69

• ribosomal S12 protein mutation results in increased expression of translation factors, which leads to enhanced protein synthesis in secondary metabolism [47]. Liu et al. reported activation of the production of bohemamines 11–13, bacterial alkaloids containing a pyrrolizidine core with two unusual methyl

Chemical and biosynthetic potential of Penicillium shentong XL-F41

• Ran Zou,
• Xin Li,
• Xiaochen Chen,
• Yue-Wei Guo and
• Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

• investigations, accompanied by fermentation media optimization, of a newly isolated fungus, Penicillium shentong XL-F41, led to the isolation of twelve compounds. Among these are two novel indole terpene alkaloids, shentonins A and B (1 and 2), and a new fatty acid 3. Shentonin A (1) is distinguished by an

• polyketides, alkaloids, sterol derivatives, terpenoids, and macrolides, with polyketides and alkaloids comprising 40% and 32% of the total, respectively. Alkaloids are a diverse group of compounds with multiple pharmacological activities, including anti-inflammatory, antibacterial, antiviral, insecticidal

• , and anticancer properties [6][7]. Historically, most alkaloids were isolated from higher plants, with a significant number found in the Apocynaceae family. Notable examples such as vinblastine, vinorelbine, vincristine, and vindesine have gained prominence as effective anticancer drugs [6][7][8][9][10

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

• antagonist 7 [33], and aldosterone synthase inhibitor 8 [34]) as well as natural products (e.g., new alkaloids deoxytryptoquivaline and deoxynortryptoquivaline from fungus Aspergillus clavatonanicus identified as natural cardiomyocyte-protective agents against cold ischemic injury [35] and possible natural

Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793

• Zhen Ying,
• Xiao-Ming Li,
• Sui-Qun Yang,
• Hong-Lei Li,
• Xin Li,
• Bin-Gui Wang and
• Ling-Hong Meng

Beilstein J. Org. Chem. 2024, 20, 470–478, doi:10.3762/bjoc.20.42

• alkaloids containing an unprecedented spiro[bicyclo[2.2.2]octane-diketopiperazine] skeleton, chevalinulins A and B, and the first cytochalasin homodimer containing a thioether bridge, verruculoid A, were identified from deep-sea cold seeps-derived fungi and were described to have potent proangiogenic and

• our attention. Several meroterpenoids, alkaloids, polyketides, and sesquiterpenoids from the species displayed various biological properties including anti-inflammatory, antimicrobial, and cytotoxic activities [7][8][9]. In the present work, two rare new examples of sulfur-containing ovalicin

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• structurally related alkaloids berberine [61][62][63][64][65] and coralyne [36][66][67] have been shown already to act as efficient photosensitizers for DNA damage. To the best of our knowledge, however, benzo[c]quinolizinium derivatives have not been investigated with respect to their DNA-photodamaging

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

• ], drugs used to treat cystic fibrosis and HIV infection, respectively. A plethora of 4-quinolones with various substitution patterns and biological activities have been isolated from natural sources. This includes plant-derived alkaloids such as graveoline [7], evocarpine [8], leiokinine [9], evollionine

• C [10], leptomerine [11], and punarivine [12]. The fruit of Evodia rutaecarpa is a particularly rich source of 4-quinolones with long-chain substituents at position 2. Various alkaloids isolated from this source have been shown to possess anti-Helicobacter pylori activity [13], inhibitory effects on

• monoamine oxidase [14], cytotoxicity against cancer cell lines [15], activity against nuclear factor of activated T cells [16], and anti-inflammatory activity [17]. Alkaloids with similar structure and anti-inflammatory activity have been isolated from another member of the Rutaceae family – Zanthoxylum

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

Sulfur-containing spiroketals from Breynia disticha and evaluations of their anti-inflammatory effect

• Ken-ichi Nakashima,
• Naohito Abe,
• Masayoshi Oyama,
• Hiroko Murata and
• Makoto Inoue

Beilstein J. Org. Chem. 2023, 19, 1604–1614, doi:10.3762/bjoc.19.117

• glycosides [1][2][3], flavan-3-ol glycosides [4], alkaloids [5], and phenolic glycosides [5][6]. Notably, sulfur-containing spiroketal glycosides, represented by breynins and epibreynins, have characteristic sesquiterpenoid-derived structures. The sesquiterpenoid phyllaemblic acid and its glycosides, which

• well as the HMBC correlations of H2-2 with C-3 and C-17, this substituent was identified as a (2-amino-2-oxoethyl)thio group. This substituent has been reported in several alkaloids isolated from plants in the Aristolochiaceae family [17][18]. Compound 3 had a β orientation for the sulfur-containing

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

• great structural variability such as polyketides, terpenoids, polyketide synthase–nonribosomal peptide synthetase (PKS–NRPS) alkaloids, and cytochalasins, which have been considered as taxonomic markers of the genus [7][8][9][10]. However, it is worthwhile to mention that the name Phomopsis should no

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• (Scheme 46) [79]. By testing several alkaloids as organocatalysts for the transformation, cinchonidine G proved to be the best catalyst for C–H sulfenylation and selenenylation of substrates in toluene at −20 or 0 °C. The reaction occurred in shorter times in the presence of N-(arylsulfanyl)succinimide

Aromatic C–H bond functionalization through organocatalyzed asymmetric intermolecular aza-Friedel–Crafts reaction: a recent update

• Anup Biswas

Beilstein J. Org. Chem. 2023, 19, 956–981, doi:10.3762/bjoc.19.72

• 2020, Pedrosa and co-workers devised a chiral heterogenous thiourea catalyst that was applied in an enantioefficient aza-Friedel–Crafts process. A series of heterogenous catalysts were prepared by condensation between alkaloids and polystyrene-derived isothiocyanates. These polymer-supported materials

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

• photocatalyst. Keywords: decarboxylative cyclization; DMAT; ergot alkaloids; photoredox catalysis; radicals; Introduction Visible-light photoredox catalysis is rapidly changing the way organic chemists approach the design and synthesis of molecules by offering new synthetic disconnection opportunities that

• : 1) it functions as the central intermediate in the biosynthetic pathways leading to numerous prenylated indole alkaloids, such as ergot alkaloids in normal biosynthesis and clavicipitic acid in derailment biosynthesis [68][69][70][71]; and 2) the mechanism of the fundamental central C-ring formation

• of all ergot alkaloids, specifically the decarboxylative cyclization of DMAT, is still a puzzle even though a radical mechanism has been proposed (Figure 1a) [72][73]. Results and Discussion Herein, we propose that visible light irradiation of the cationic iridium photocatalyst Ir[dF(CF3)ppy]2(dtbbpy

Non-peptide compounds from Kronopolites svenhedini (Verhoeff) and their antitumor and iNOS inhibitory activities

• Yuan-Nan Yuan,
• Jin-Qiang Li,
• Hong-Bin Fang,
• Shao-Jun Xing,
• Yong-Ming Yan and
• Yong-Xian Cheng

Beilstein J. Org. Chem. 2023, 19, 789–799, doi:10.3762/bjoc.19.59

• activity have revealed the presence of antimicrobial peptides [5], defensive alkaloids [6], and defensive long chain alcohol acetates [7]. Historically, in China, numerous records documented the utilization of animals like arthropods for medicinal purposes. Millipedes hereby represent a traditional Chinese

Total synthesis: an enabling science

• Bastien Nay

Beilstein J. Org. Chem. 2023, 19, 474–476, doi:10.3762/bjoc.19.36

• syntheses ever published in the Beilstein Journal of Organic Chemistry, such as those of frog indolizidine alkaloids [5][6]. However, no thematic issue specifically related to total synthesis has been published before, and we thought it would be time to fill this gap. Although innovative developments are

Identification and determination of the absolute configuration of amorph-4-en-10β-ol, a cadinol-type sesquiterpene from the scent glands of the African reed frog Hyperolius cinnamomeoventris

• Angelique Ladwig,
• Markus Kroll and
• Stefan Schulz

Beilstein J. Org. Chem. 2023, 19, 167–175, doi:10.3762/bjoc.19.16

• composition of the gular gland blend, including always 14. Diet-dependent uptake of compounds by frogs usually results in individual differences in compound composition, as has been observed, e.g., for skin alkaloids of Madagascan poison frogs [26]. Finally, experiments with mantellines showed that at least

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

• products by chemoselective redox reactions. Divergent total synthesis of Galbulimima alkaloids (Shenvi 2022) [62]: Members of the Galbulimima alkaloids extracted from rainforest canopy trees were found to possess neuroactive properties, such as antagonistic activity at muscarinic receptors [63

• reduction steps allowed the total synthesis of GB13 (8), himgaline (126), and GB22 (125) in only one third of the number of steps of prior syntheses (Scheme 10). Concise syntheses of eburnane alkaloids (Qin 2018) [68][69]: Eburnane indole alkaloids comprise a highly diverse class of natural products mainly

• distributed in Southeast Asia and China [70]. Compounds of this class are traditionally used for detoxification and as anti-inflammatory agents in Chinese medicine [71]. Qin and co-workers reported the asymmetric total syntheses of several eburnane alkaloids. Therein, they relied on one of their previous

Synthesis of (−)-halichonic acid and (−)-halichonic acid B

• Keith P. Reber and
• Emma L. Niner

Beilstein J. Org. Chem. 2022, 18, 1629–1635, doi:10.3762/bjoc.18.174

• assays have not yet been investigated. Our group was particularly interested in the structure of halichonic acid ((+)-1), which shares the same bridged bicyclic ring system found in many of the Aristotelia alkaloids [6]. Since our lab recently reported a synthesis of the natural product aristoquinoline

Synthetic study toward the diterpenoid aberrarone

• Liang Shi,
• Zhiyu Gao,
• Yiqing Li,
• Yuanhao Dai,
• Yu Liu,
• Lili Shi and
• Hong-Dong Hao

Beilstein J. Org. Chem. 2022, 18, 1625–1628, doi:10.3762/bjoc.18.173

• tetracyclic carbon skeleton yet-to-be found in Pseudopterogorgia elisabethae species, although related cyclohexane-angularly-fused triquinane systems have been found in waihoensene (3), conidiogenone (4), lycopodium alkaloids magellamine (5) and lycojaponicumin C (6) (Figure 1). Its seven stereogenic centers

Formal total synthesis of macarpine via a Au(I)-catalyzed 6-endo-dig cycloisomerization strategy

• Jiayue Fu,
• Bingbing Li,
• Zefang Zhou,
• Maosheng Cheng,
• Lu Yang and
• Yongxiang Liu

Beilstein J. Org. Chem. 2022, 18, 1589–1595, doi:10.3762/bjoc.18.169

• . The convergent synthetic strategies feature the utilization of Au(I)-catalyzed cycloisomerizations of a 1,5-enyne and alkynyl ketone substrates, which were prepared by Sonogashira coupling reactions. Keywords: benzo[c]phenanthridine alkaloids; 1,5-enyne; formal total synthesis; gold catalysis

• ; macarpine; Introduction Benzo[c]phenanthridine alkaloids are an ancient and influential category of isoquinoline alkaloids, mainly found in Papaveraceae and Rutaceae (Scheme 1) [1][2]. According to their oxidation states, benzo[c]phenanthridine alkaloids can be divided into two types: partially

• hydrogenated base and fully aromatized base, in which natural fully aromatic alkaloids can be further classified into three subclasses: O4-base, O5-base, and O6-base [3]. Among these alkaloids macarpine is the most oxidized tetracyclic alkaloid with many bioactivities, including anesthesia, anticancer, anti

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

• 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

• products, warranting inclusion in current and future biodiscovery programs. Verongid sponges have been a prolific source of bioactive and novel bromotyrosine-derived alkaloids with more than 374 compounds currently reported [1]. Whilst this particular structure class includes a large number of simple

• bromotyrosine derivatives, more complex natural products containing spirocyclohexadienylisoxazolines, spirooxepinisoxazolines and oximes have been reported [3][4]. This class of marine alkaloids possess unique functional groups, 3D architecture and interesting pharmacology such as cytotoxicity [5][6

Vicinal ketoesters – key intermediates in the total synthesis of natural products

• Marc Paul Beller and
• Ulrich Koert

Beilstein J. Org. Chem. 2022, 18, 1236–1248, doi:10.3762/bjoc.18.129

• for different purposes in the syntheses of a range of oxindole alkaloids. The start of the synthesis of (rac)-corynoxine (76) was the conversion of tryptamine (70) to oxindole 71, which was used in a chemoselective Mannich reaction with aldehyde 72, introducing the α-ketoester moiety (Scheme 12) [27

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• associated biological activities and relevance to the naturally occurring alkaloids [1], 1,4-dihydro-3(2H)-isoquinolones (1,4-DHIQs) undoubtedly represent a privileged scaffold [2] for drug design considering such diversely bioactive compounds documented in the literature as ligand for serotonin 5-HT1A

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

• and substituents was also studied during investigation of fluorescence properties of these derivatives. Keywords: β-carboline; DABCO; fluorescence; MBH reaction; Michael addition; structure–fluorescence activity relationship; Introduction Among the polycyclic alkaloids based on indole, the tricyclic

• structure β-carboline represents a promising class of pyridoindole alkaloids with a variety of biological activities which make them interesting synthetic targets [1][2][3][4][5][6][7][8]. Alkaloids containing the β-carboline nucleus in their molecular architecture are present ubiquitously in nature and a

Anti-inflammatory aromadendrane- and cadinane-type sesquiterpenoids from the South China Sea sponge Acanthella cavernosa

• Shou-Mao Shen,
• Qing Yang,
• Yi Zang,
• Jia Li,
• Xueting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 916–925, doi:10.3762/bjoc.18.91

• diterpenes [7][8], alkaloids [9], and steroids [10], have been isolated and characterized. In connection with our continuing studies of Chinese marine invertebrates to search for novel and bioactive secondary metabolites, we have recently studied the sponge A. cavernosa collected from Ximao Island of Hainan

Copper-catalyzed multicomponent reactions for the efficient synthesis of diverse spirotetrahydrocarbazoles

• Shao-Cong Zhan,
• Ren-Jie Fang,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 796–808, doi:10.3762/bjoc.18.80

• Tetrahydrocarbazole is one of the most privileged heterocyclic core structures. It widely exists in various naturally occurring alkaloids and pharmacologically active compounds exhibiting important bioactivities such as antitumor activity and antiprotein kinase C activity [1][2][3]. Additionally, the corresponding