Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• was converted to the epoxide 7.5 by cyclisation in the presence of potassium carbonate in methanol, thus producing the interesting building block 7.5. A second option, optimized to avoid the formation of epoxide, used a hindered base and the reactive benzyltriflate as electrophile to achieve under

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

• optimized conditions in hand, diverse 2-arylated pyridines were screened resulting in the corresponding products 74 in good yields. Allene, a cumulated diene and an important building block in organic synthesis has versatile biological properties and is also an important subunit in various natural products

Facile access to 3-sulfonylquinolines via Knoevenagel condensation/aza-Wittig reaction cascade involving ortho-azidobenzaldehydes and β-ketosulfonamides and sulfones

• Ksenia Malkova,
• Andrey Bubyrev,
• Stanislav Kalinin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 800–807, doi:10.3762/bjoc.19.60

• synthesis of quinoline-3-sulfonyl chlorides which are the most common reagents for their preparation. As a possible solution, the approach to the heterocyclic core construction from a sulfonamide-containing building block may be considered. In turn, diversely substituted quinoline-3-sulfones are available

Construction of hexabenzocoronene-based chiral nanographenes

• Ranran Li,
• Di Wang,
• Shengtao Li and
• Peng An

Beilstein J. Org. Chem. 2023, 19, 736–751, doi:10.3762/bjoc.19.54

• nanomaterials, the design, and construction of chiral nanographenes is a hot topic recently. As a classic nanographene unit, hexa-peri-hexabenzocoronene generally serves as the building block for nanographene synthesis. This review summarizes the representative examples of hexa-peri-hexabenzocoronene-based

• derivatives have attracted increasing attention due to their specific optoelectronic properties [5][29]. HBC thus generally serves as a reference structure or building block to construct chiral NGs which are currently receiving a lot of interest in carbon-based materials science. This review will mainly focus

• the prefused building block in a 49% yield. Then naphthalene and phenanthrene residues were introduced into compound 33 through Suzuki coupling reaction, the corresponding precursors 34 and 36 were obtained respectively in high yields. The final cyclodehydrogenation using DDQ and TfOH proceeded

Palladium-catalyzed enantioselective three-component synthesis of α-arylglycine derivatives from glyoxylic acid, sulfonamides and aryltrifluoroborates

• Bastian Jakob,
• Nico Schneider,
• Luca Gengenbach and
• Georg Manolikakes

Beilstein J. Org. Chem. 2023, 19, 719–726, doi:10.3762/bjoc.19.52

• sterically hindered arylboronic acids. Herein, we report an improved version of this palladium-catalyzed enantioselective three-component reactions using aryltrifluoroborates as replacement of the arylboronic acid building block (Scheme 1d). The broader scope of this 2nd generation protocol is exploiting a

• slow release of the boronic acid from the aryltrifluoroborates and enables to enantioselectively synthesize of a broader variety of arylglycines, including a common building block for several biologically active compounds. Results and Discussion During our previous studies, we observed that the

• to our previous study with the corresponding boronic acids [22]). Synthesis of both enantiomers of arylglycine building block 18. Reaction optimization. Supporting Information Supporting Information File 176: Experimental section and characterization data. Funding Financial support by the research

Synthesis and reactivity of azole-based iodazinium salts

• Thomas J. Kuczmera,
• Annalena Dietz,
• Andreas Boelke and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2023, 19, 317–324, doi:10.3762/bjoc.19.27

• imidazoiodaziniums, we show highly delicate post-oxidation functionalizations retaining the hypervalent iodine center. Keywords: building block; heterocycles; hypervalent compounds; iodonium salts; one-pot synthesis; Introduction The chemistry of hypervalent iodine compounds, in particular aryl-λ3-iodanes, is

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures

• Bram Ryckaert,
• Ellen Demeyere,
• Frederick Degroote,
• Hilde Janssens and
• Johan M. Winne

Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12

• synthesis of 1,4-dithiane-type ring systems is not the primary focus of this review, the synthetic accessibility of these building blocks is of course an important consideration, and it impacts the utility of any building block-based strategy [19][20][21][22][23][24]. The commercially available 1,4-dithiane

• access to building block 2. The benzannelated series of 1,4-dithiane heterocycles 5–7 can in principle be obtained using Parham’s α-halocarbonyl condensation and rearrangement approach, starting from benzene-1,2-dithiol. More conveniently, however, ethanedithiol and cyclohexanone can be condensed, and

• quantities from a limited number of suppliers. Oxidation and dehydration of 5 to the fully unsaturated ring system 6 is quite straightforward (especially compared to the same reactions on 1,4-dithiane (1)), and yields the useful building block 6. For the availability of the disulfone series of derivatives of

Navigating and expanding the roadmap of natural product genome mining tools

• Friederike Biermann,
• Sebastian L. Wenski and
• Eric J. N. Helfrich

Beilstein J. Org. Chem. 2022, 18, 1656–1671, doi:10.3762/bjoc.18.178

• by tailoring enzymes that decorate the NP scaffold. Assembly line-like pathways are characterized by mega enzymes, which can be subdivided into modules. Each module is responsible for the incorporation (and/or processing) of one building block into the nascent product. A “textbook” extension module

• minimally harbors three core domains, responsible for the activation and loading, tethering, and condensation of building blocks and intermediates. The biosynthesis is directional and starts at the N-terminal module with the activation and loading of the first building block onto the assembly line (Figure

•  2A) [21]. The specificity of the activating domain determines the type of building block incorporated. The growing intermediate stays permanently bound to the assembly line until the final product is released at the C-terminal module. However, modules can also be skipped, used for the modification of

Simple synthesis of multi-halogenated alkenes from 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane)

• Yukiko Karuo,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2022, 18, 1567–1574, doi:10.3762/bjoc.18.167

• ) has been used as a fluorine-containing building block for the construction of trifluoromethyl and difluoromethylene motifs [1][2]. Such structures have been found in several multifunctional materials and biologically important molecules (Figure 1) [3][4][5][6][7]. The halothane structure contains two

Solid-phase total synthesis and structural confirmation of antimicrobial longicatenamide A

• Takumi Matsumoto,
• Takefumi Kuranaga,
• Yuto Taniguchi,
• Weicheng Wang and
• Hideaki Kakeya

Beilstein J. Org. Chem. 2022, 18, 1560–1566, doi:10.3762/bjoc.18.166

• unavailable building blocks 7 and 10 were chemically constructed from readily available starting materials. The synthesis of building block 10 commenced with the synthesis of compound 15 through Wittig reaction of Garner’s aldehyde (13) [16], which was readily obtained from tert-butyloxycarbonyl (Boc

• longicatenamides A–D (1–4). LC–MS extracted ion chromatograms (EICs) of synthesized and natural 1. Column: Imtakt Cadenza CD-C18 3 × 150 mm; eluent: MeCN/H2O/TFA 30:70:0.05, isocratic, 0.2 mL/min; 40 °C. Retrosynthesis of longicatenamycin A (1). Synthesis of building block 10. Synthesis of building block 7. Total

A study of the DIBAL-promoted selective debenzylation of α-cyclodextrin protected with two different benzyl groups

• Naser-Abdul Yousefi,
• Morten L. Zimmermann and
• Mikael Bols

Beilstein J. Org. Chem. 2022, 18, 1553–1559, doi:10.3762/bjoc.18.165

• substances such as pharmaceuticals or fragrances is exploited since it is cheap, harmless and biodegradable [4]. It is also a useful building block for sensors and/or capture devices, advanced materials, and even artificial enzymes. Most such uses require that compound 1 can be chemically modified so that

Synthesis of C6-modified mannose 1-phosphates and evaluation of derived sugar nucleotides against GDP-mannose dehydrogenase

• Sanaz Ahmadipour,
• Alice J. C. Wahart,
• Jonathan P. Dolan,
• Laura Beswick,
• Chris S. Hawes,
• Robert A. Field and
• Gavin J. Miller

Beilstein J. Org. Chem. 2022, 18, 1379–1384, doi:10.3762/bjoc.18.142

• interventions that could halt its production would be of significant value. Within the biosynthetic assembly of alginate there is a critical dependence upon the provision of one sugar nucleotide building block, GDP-mannuronic acid (GDP-ManA, 5). This material is sourced from the cytosolic metabolic pool

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

• diesters and ester amides as key intermediates (+)-Awajanomycin Diethyl mesoxalate (90a) is a valuable building block due to the high density of carbon atoms in high oxidation states. As a vic-tricarbonyl compound, its central keto group is an especially potent electrophile. The Koert group used this

Mechanochemical bottom-up synthesis of phosphorus-linked, heptazine-based carbon nitrides using sodium phosphide

• Blaine G. Fiss,
• Georgia Douglas,
• Michael Ferguson,
• Jorge Becerra,
• Jesus Valdez,
• Trong-On Do,
• Tomislav Friščić and
• Audrey Moores

Beilstein J. Org. Chem. 2022, 18, 1203–1209, doi:10.3762/bjoc.18.125

• constitutes the building block of g-CN, as opposed to in a linking position. Computational studies by Hartley and Martsinovich have investigated the influence of various linkers, including phosphorus atoms, on both the structure and optical behavior of heptazine-based graphitic carbon nitrides [3]. Yet

Reductive opening of a cyclopropane ring in the Ni(II) coordination environment: a route to functionalized dehydroalanine and cysteine derivatives

• Oleg A. Levitskiy,
• Olga I. Aglamazova,
• Yuri K. Grishin and
• Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2022, 18, 1166–1176, doi:10.3762/bjoc.18.121

• provides targeted pharmacophoric properties of the bio-active molecule [23] but also opens a route to its further functionalization, being a building block with wide variety of reactivity. A donor–acceptor cyclopropane concept suggested in the 1980s [24] became extremely popular in the recent decade [25

Synthesis of protected precursors of chitin oligosaccharides by electrochemical polyglycosylation of thioglycosides

• Md Azadur Rahman,
• Kana Kuroda,
• Hirofumi Endo,
• Norihiko Sasaki,
• Tomoaki Hamada,
• Hiraku Sakai and
• Toshiki Nokami

Beilstein J. Org. Chem. 2022, 18, 1133–1139, doi:10.3762/bjoc.18.117

• . Contrary, thioglycoside 1c (Ar = 4-MeC6H4, Eox = 1.47 V vs SCE), which had the lowest oxidation potential, showed the lowest conversion (51%) and the lowest yield of tetrasaccharide 4c (2%) [8]. This being the case, lower conversion of the building block 1c and lower yield of oligosaccharides 2c–4c

• , building block 1a (0.20 mmol, 109 mg) per cycle as 0.2 M solution in dry CH2Cl2. Electrochemical dimerization of tetrasaccharide 4a. Supporting Information Supporting Information File 240: Additional experimental details and compound characterization data. Funding T. N. acknowledges financial support

The stereochemical course of 2-methylisoborneol biosynthesis

• Binbin Gu,
• Anwei Hou and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2022, 18, 818–824, doi:10.3762/bjoc.18.82

• from Micromonospora humi can convert DMAPP into (R)-2-Me-IPP with a methyltransferase [27], naturally providing the C6 building block for this hypothetical alternative pathway towards 1 (Scheme 1B). Today the genomes of many bacteria from the genus Streptomyces have been made available, showing that

Heteroleptic metallosupramolecular aggregates/complexation for supramolecular catalysis

• Prodip Howlader and
• Michael Schmittel

Beilstein J. Org. Chem. 2022, 18, 597–630, doi:10.3762/bjoc.18.62

• that the chiral moiety should be incorporated in the ligand unit in order to provide an enantiopure assembly with an asymmetric cavity. 1,1'-Binaphthol (BINOL) is one such chiral building block, which has been successfully utilized to carry out numerous asymmetric catalytic reactions [74]. Keeping this

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

• synthetic building block 2-nitroperchlorobutadiene (1). 3-(Alkyl)(2-hydroxyethyl)aminopyrazoles 7 are accessible from the reaction of oxazolidine derivative 6 with 7-chloro-4-hydrazinylquinoline. Oxidation of sulfane 9d led to the formation of the pharmacologically interesting sulfoxide 10d. The newly

Borylated norbornadiene derivatives: Synthesis and application in Pd-catalyzed Suzuki–Miyaura coupling reactions

• Robin Schulte and
• Heiko Ihmels

Beilstein J. Org. Chem. 2022, 18, 368–373, doi:10.3762/bjoc.18.41

• congested derivative 2b has significantly suppressed reactivity, the monosubstituted derivative 2a was shown to be a very useful and complementary building block for the synthesis of monoarylated norbornadiene derivatives that carry no further substituents. It should be noted, however, that the inverse

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

• suitable protected linear precursor A (Scheme 2, PG: protecting group), the resulting carboxylic acid obtained can directly be activated and subjected to cyclization. If the glycine allyl ester is incorporated as the last building block into the C-terminus of the peptide, this concept should provide a high

Synthesis and bioactivity of pyrrole-conjugated phosphopeptides

• Qiuxin Zhang,
• Weiyi Tan and
• Bing Xu

Beilstein J. Org. Chem. 2022, 18, 159–166, doi:10.3762/bjoc.18.17

• similar activity compared to their phosphorylated counterparts. These results indicate that these peptide assemblies are rather compatible with cells. Compounds 13 and 14, both possessing a pyrrole building block on the side chain, hardly inhibit the HeLa cells. While 15a and 15b exhibit slight

High-speed C–H chlorination of ethylene carbonate using a new photoflow setup

• Takayoshi Kasakado,
• Takahide Fukuyama,
• Tomohiro Nakagawa,
• Shinji Taguchi and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2022, 18, 152–158, doi:10.3762/bjoc.18.16

• [14][15][16][17][18][19][20]. Vinylene carbonate also serves as a useful synthetic building block for Diels–Alder reactions [21][22][23][24][25] and polymerization [26][27][28][29][30]. Results and Discussion Using a PTFE tube and PTFE connectors, we connected the photoflow setup with a chlorine gas

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

• ppm appeared, implying chemical exchange and therefore the presence of rotamers (Supporting Information File 1 in Figure S53b). The synthesis of methyl 5-(N-Boc-piperidin-4-yl)-1,2-oxazole-4-carboxylate (4h), a nonchiral amino acid-like building block, was obtained by the reaction of β-enamino

Selective sulfonylation and isonitrilation of para-quinone methides employing TosMIC as a source of sulfonyl group or isonitrile group

• Chuanhua Qu,
• Run Huang,
• Yong Li,
• Tong Liu,
• Yuan Chen and
• Guiting Song

Beilstein J. Org. Chem. 2021, 17, 2822–2831, doi:10.3762/bjoc.17.193

• standard conditions, the desired products 3b or 4b were obtained with yields of 92% and 88%, respectively. Second, the sulfonylated diarylmethane 3b obtained through the C–S bond-cleavage sulfonylation reaction is a versatile building block for preparing diarylmethane derivatives through a nucleophilic